From eoas-seminar at lists.fsu.edu Thu Oct 1 14:52:44 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 1 Oct 2020 14:52:44 -0400 Subject: [Eoas-seminar] With sadness Message-ID: We are saddened and shocked by the sudden passing of Katherine Payne Gooding. Katherine was a senior majoring in meteorology in the department of Earth, Ocean and Atmospheric Science. Although she transferred to Florida State from the US Naval Academy in the Spring of 2020, she was on track to graduate in the Spring of 2021. We offer our condolences and deepest sympathy to her family, her friends and the FSU/EOAS community. She will be remembered by her professors and classmates for her kindness and bright smile. We are mourning her loss and will miss her. Vincent Salters Chair ----------------------------------- Dr. Vincent J.M. Salters Professor and Chair Department of Earth, Ocean and Atmospheric Sciences Labs at: Geochemistry Program of the National High Magnetic Field Laboratory Florida State University Tallahassee, Florida Phone: 850-644-1934, Skype: vsalters -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 5 16:14:16 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 5 Oct 2020 20:14:16 +0000 Subject: [Eoas-seminar] EOAS Colloquium at 3:30 PM, Friday, Oct. 9 Message-ID: Our next speaker in the EOAS Colloquium this Friday, Oct. 9 at 3:30 pm will be Dr. Shineng Hu of the Columbia University / Duke University Global climate impacts of Indian Ocean warming The tropical Indian Ocean (TIO) has warmed by 1?C since the 1950s, at a faster rate than the other tropical oceans. In this talk, I will discuss how this warming can affect the Atlantic Ocean via atmospheric and oceanic teleconnections. Specifically, by reorganizing the atmospheric Walker circulation in the equatorial band, this warming can reduce precipitation in the tropical Atlantic, resulting in pronounced surface salinity anomalies. On multidecadal timescales, these anomalies are advected to northern high latitudes and strengthen the Atlantic meridional overturning circulation (AMOC). The resultant AMOC changes lead to a stronger hemispheric asymmetry and a northward shifted intertropical convergence zone (ITCZ). On shorter timescales, Indian Ocean warming generates a train of atmospheric planetary waves, which reach the subpolar North Atlantic, strengthen surface westerly winds there, and cool the underlying ocean within a few months to years. This mechanism could potentially explain the suppressed warming in the subpolar North Atlantic (known as the "warming hole") seen in the observational record. Further, I will discuss the implications for past and future climate changes and ocean interbasin teleconnections. Via Zoom: https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 The informal virtual chat will start at 3:00 PM through the same zoom link. Please contact Dr Zhaohua Wu if you would like to meet privately with the speaker in that day. The more detailed zoom meeting information is appended ========================== Zhaohua Wu is inviting you to a scheduled Zoom meeting. Topic: EOAS Colloquium, Oct. 9 Time: Oct 9, 2020 03:00 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 Meeting ID: 925 5686 6443 Passcode: 451688 One tap mobile +13017158592,,92556866443# US (Germantown) +16465588656,,92556866443# US (New York) Dial by your location +1 301 715 8592 US (Germantown) +1 646 558 8656 US (New York) +1 312 626 6799 US (Chicago) +1 669 900 9128 US (San Jose) +1 253 215 8782 US (Tacoma) +1 346 248 7799 US (Houston) Meeting ID: 925 5686 6443 Find your local number: https://fsu.zoom.us/u/al1Y5u3NL Join by SIP 92556866443 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 925 5686 6443 Passcode: 451688 -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 8 09:25:24 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 8 Oct 2020 09:25:24 -0400 Subject: [Eoas-seminar] Please join us for a seminar by Prof. Dewar on Wednesday October 21 at 10am Message-ID: with the catchy title of "Thoughts about things I have been thinking of late". The detailed abstract is " There might or might not be something interesting here. Please help me decide" Attend at you own risk :-) Hope to see you there - will email the zoom link a day before the seminar. Best, Eric -- Eric Chassignet Professor and Director Center for Ocean-Atmospheric Prediction Studies (COAPS) Florida State University 2000 Levy Avenue, Building A, Suite 292 P.O. Box 3062741 Tallahassee, FL 32306-2741 Office : (1) 850-645-7288 COAPS : (1) 850-644-3846 Cell : (1) 850-524-0033 (urgent matters only) FAX : (1) 850-644-4841 E-mail : echassignet at fsu.edu http://www.coaps.fsu.edu From eoas-seminar at lists.fsu.edu Fri Oct 9 09:58:30 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 9 Oct 2020 09:58:30 -0400 Subject: [Eoas-seminar] REMINDER TODAY: Fwd: EOAS Colloquium at 3:30 PM, Friday, Oct. 9 In-Reply-To: References: Message-ID: Our next speaker in theEOASColloquiumTODAY at 3:30 pm will be Dr. Shineng Hu of the Columbia University / Duke University Global climate impacts of Indian Ocean warming The tropical Indian Ocean (TIO) has warmed by 1?C since the 1950s, at a faster rate than the other tropical oceans. In this talk, I will discuss how this warming can affect the Atlantic Ocean via atmospheric and oceanic teleconnections. Specifically, by reorganizing the atmospheric Walker circulation in the equatorial band, this warming can reduce precipitation in the tropical Atlantic, resulting in pronounced surface salinity anomalies. On multidecadal timescales, these anomalies are advected to northern high latitudes and strengthen the Atlantic meridional overturning circulation (AMOC). The resultant AMOC changes lead to a stronger hemispheric asymmetry and a northward shifted intertropical convergence zone (ITCZ). On shorter timescales, Indian Ocean warming generates a train of atmospheric planetary waves, which reach the subpolar North Atlantic, strengthen surface westerly winds there, and cool the underlying ocean within a few months to years. This mechanism could potentially explain the suppressed warming in the subpolar North Atlantic (known as the "warming hole") seen in the observational record. Further, I will discuss the implications for past and future climate changes and ocean interbasin teleconnections. Via Zoom: https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 The informal virtual chat will start at 3:00 PM through the same zoom link. Please contact Dr Zhaohua Wu if you would like to meet privately with the speaker in that day. The more detailed zoom meeting information is appended ========================== Zhaohua Wu is inviting you to a scheduled Zoom meeting. Topic: EOAS Colloquium, Oct. 9 Time: Oct 9, 2020 03:00 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 *Meeting ID: 925 5686 6443* *Passcode: 451688* One tap mobile +13017158592,,92556866443# US (Germantown) +16465588656,,92556866443# US (New York) Dial by your location ? ? ? ? +1 301 715 8592 US (Germantown) ? ? ? ? +1 646 558 8656 US (New York) ? ? ? ? +1 312 626 6799 US (Chicago) ? ? ? ? +1 669 900 9128 US (San Jose) ? ? ? ? +1 253 215 8782 US (Tacoma) ? ? ? ? +1 346 248 7799 US (Houston) Meeting ID: 925 5686 6443 Find your local number: https://fsu.zoom.us/u/al1Y5u3NL Join by SIP 92556866443 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 925 5686 6443 Passcode: 451688 -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar From eoas-seminar at lists.fsu.edu Fri Oct 9 10:06:50 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 9 Oct 2020 14:06:50 +0000 Subject: [Eoas-seminar] EOAS Colloquium at 3:30 PM, Friday, Oct. 9 In-Reply-To: References: Message-ID: Hi all, Just a reminder that there is an EOAS colloquium today. The speaker, title and abstract of the talk are Dr. Shineng Hu of the Columbia University / Duke University Global climate impacts of Indian Ocean warming The tropical Indian Ocean (TIO) has warmed by 1?C since the 1950s, at a faster rate than the other tropical oceans. In this talk, I will discuss how this warming can affect the Atlantic Ocean via atmospheric and oceanic teleconnections. Specifically, by reorganizing the atmospheric Walker circulation in the equatorial band, this warming can reduce precipitation in the tropical Atlantic, resulting in pronounced surface salinity anomalies. On multidecadal timescales, these anomalies are advected to northern high latitudes and strengthen the Atlantic meridional overturning circulation (AMOC). The resultant AMOC changes lead to a stronger hemispheric asymmetry and a northward shifted intertropical convergence zone (ITCZ). On shorter timescales, Indian Ocean warming generates a train of atmospheric planetary waves, which reach the subpolar North Atlantic, strengthen surface westerly winds there, and cool the underlying ocean within a few months to years. This mechanism could potentially explain the suppressed warming in the subpolar North Atlantic (known as the "warming hole") seen in the observational record. Further, I will discuss the implications for past and future climate changes and ocean interbasin teleconnections. The Zoom Link is https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 You may meet the speaker at 3:00 PM through the same zoom link. See you then. Cheers, Zhaohua ========================== Zhaohua Wu is inviting you to a scheduled Zoom meeting. Topic: EOAS Colloquium, Oct. 9 Time: Oct 9, 2020 03:00 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/92556866443?pwd=bTFlc1Rnc0QrUG84UFlvN1MxdzdlUT09 Meeting ID: 925 5686 6443 Passcode: 451688 One tap mobile +13017158592,,92556866443# US (Germantown) +16465588656,,92556866443# US (New York) Dial by your location +1 301 715 8592 US (Germantown) +1 646 558 8656 US (New York) +1 312 626 6799 US (Chicago) +1 669 900 9128 US (San Jose) +1 253 215 8782 US (Tacoma) +1 346 248 7799 US (Houston) Meeting ID: 925 5686 6443 Find your local number: https://fsu.zoom.us/u/al1Y5u3NL Join by SIP 92556866443 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 925 5686 6443 Passcode: 451688 -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar From eoas-seminar at lists.fsu.edu Mon Oct 12 09:48:53 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 12 Oct 2020 09:48:53 -0400 Subject: [Eoas-seminar] No Colloquium Friday Oct 16th Message-ID: There will be no seminar this Friday Oct 16th as the speaker had to cancel due to a family emergency.? Our next colloquium will be Friday Oct 23. From eoas-seminar at lists.fsu.edu Mon Oct 12 11:42:19 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 12 Oct 2020 15:42:19 +0000 Subject: [Eoas-seminar] MET Seminar Series, Thursday, Oct. 15, 2020 at 3:30 PM Message-ID: Dear colleagues, I am here, on behalf of Drs. Wing and Sura and with great pleasure, to announce that we will have a MET seminar series this semester. The first speaker will be Dr. Wanying Kang of MIT and she will give a talk on Thursday, Oct. 15, 2020 at 3:30 PM. Wanying earned her Ph.D later last year at Harvard University and is currently a MIT distinguished university postdoctoral fellow (https://wanyingkang.com/cv/). She has published extensively in different areas in climate dynamics, including Madden-Julian Oscillation (a well-known tropical phenomena) and its interactions with high latitude and high altitude phenomena, climate dynamics of other planets or moons in and out the solar system. The detailed information of her seminar is here (also see the attached flyer): Title: What shapes Ice Shell of Enceladus? Abstract: Beneath the icy shell encasing Enceladus, a small icy moon of Saturn, a global ocean of liquid water ejects geyser-like sprays into space through fissures concentrated near the south pole, making it one of the places with the highest potential of finding extraterrestrial life. The existence of an ocean has been attributed to the heat generated in dissipative processes associated with the deformation of Enceladus by tidal forcing. However, it remains unclear whether heat is mostly generated in its ice shell or silicate core, and what gives rise to the dramatic asymmetry between the northern and southern hemispheres. Answering these questions is crucial if we are to understand the dynamics behind the active south pole and to unravel patterns of ocean circulation, tracer transport and biosignatures important for the habitability and detectability of potential life. In this presentation, we discuss how we might infer the partition of heat generation between ice shell and core, and demonstrate how the hemispheric asymmetry of ice shell topography could form out of initial random perturbations through mode growth. Time: Thursday, Oct. 15, 2020 at 3:30 PM Zoom Link: https://fsu.zoom.us/j/93591419276?pwd=Q3NrS3hNM2hzNnFVWkFzbWZBeTc1QT09 Please contact me if you want to meet her. Also, the pre-seminar social will start at 3:00 PM that day through the same Zoom Link. Best, Zhaohua -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: MET_Seminar_Flyer_Kang.pdf Type: application/pdf Size: 954560 bytes Desc: MET_Seminar_Flyer_Kang.pdf URL: From eoas-seminar at lists.fsu.edu Mon Oct 12 16:29:22 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 12 Oct 2020 20:29:22 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Thomas Gard, Monday, October 26, 2020, 9:00 AM, on Zoom 93507804077 Message-ID: Meteorology Seminar Thomas Gard M.S. Meteorology Candidate Title: Examining the utility of ProbSevere For Predicting Pulse Severe Thunderstorms Major Professor: Dr. Henry Fuelberg Date: Monday, October 26th, 2020 Time: 9:00 AM Location: Zoom Meeting URL: https://fsu.zoom.us/j/93507804077 ABSTRACT Disorganized, weakly forced convection is a routine summertime occurrence in the Southeast United States. Pulse severe storms are single cell thunderstorms that produce severe wind and/or severe hail for a brief period of time. These thunderstorms pose a major warm season forecasting problem, since forecasters presently do not have sufficient guidance to know which, if any, of the many single cells will become severe. The empirical Probability of Severe (ProbSevere) model, developed by the Cooperative Institute for Meteorological Satellite Studies (CIMSS), fuses real-time data to produce short-term, statistically derived probabilistic forecasts of thunderstorm intensity. Objects corresponding to storms are created from satellite and radar data, tracked in two-minute timesteps, and trained on a composite of all modes of severe thunderstorms. ProbSevere has been found to increase forecaster confidence and forecast lead time. However, it is unclear how well ProbSevere performs specifically for pulse severe storms. This study evaluates the ability of ProbSevere to represent and predict pulse severe storms. Pulse severe environments are often classified as being unstable (CAPE * 2000 J kg-1) and weakly sheared (0-6 km AGL shear < 10 m s-1). ProbSevere objects fitting the accepted definition of a pulse severe environment were matched with severe events from Storm Data to create a dataset of ProbSevere objects that corresponded to pulse severe thunderstorms. A null dataset comprised of objects that corresponded to pulse severe environments but did not match with a severe event was also created. Pulse severe objects were evaluated at two times - the time at object initialization and the time of the severe event. This way, the evolution of objects could be analyzed as would be done by a forecaster in real time. Objects were examined in four ways - 1) their temporal evolution, 2) their spatial evolution, 3) how well the severe hail and cellular wind models perform for pulse severe objects, and 4) how well individual predictors discriminate between severe and nonsevere objects. Results reveal that ProbSevere's ability to represent pulse severe thunderstorms is limited, both temporally and spatially. There is little difference between severe hail-producing objects and severe wind-producing objects. At object initialization, ProbSevere exhibits insignificant probabilities of severe weather. At the time of severe events, probabilities are greater but still small. No predictor, with the exception of lightning flash rate, shows a strong correlation with the increasing probability of pulse severe events. Furthermore, no discernable difference in the distribution of probabilities as a function of predictor value is found between severe and nonsevere objects. This study demonstrates that ProbSevere's ability to represent pulse severe thunderstorms is limited, and that ProbSevere is not optimized to give forecasters sufficient guidance for pulse severe storm events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Tue Oct 13 11:00:27 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Tue, 13 Oct 2020 15:00:27 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Fucheng Yang, Tuesday, October 27, 2020, 3:30PM, on Zoom 93626378066 Message-ID: Meteorology Seminar Fucheng Yang M.S. Meteorology Candidate Title: The Origins of Asymmetry in Mid-latitude Annual Cycle Major Professor: Dr. Zhaohua Wu Date: Tuesday, October 27th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/93626378066) ABSTRACT For almost all climate variables, the annual cycle of a climate variable is often the most dominant component of that variable. Although such annual cycle is suggested to tie with the annual changes of the solar irradiance arriving at the top of atmosphere, the detailed physical mechanisms causing the annual cycle remain to be worked out. In this study, we make effort to understand the physical mechanisms behind the observed temporally asymmetric annual cycle of surface air temperature (SAT) over various regions of the Earth. Since the dominant component of the Fourier decomposition of SAT that causes the temporal asymmetry of SAT is its semiannual component, we seek to understand the origins of the semiannual component. We found that, in midlatitudes where the semiannual component of the solar irradiance approaches to zero, the semiannual component of SAT is not directly solar irradiance forced; but rather, it is caused by the annual changes of the heat capacity of the effective surface layer in response to the annual cycle of solar irradiance. We also assess the relative roles of direct forcing and indirect response in generating temporal asymmetry of annual cycle over different regions of the globe. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Wed Oct 14 11:32:26 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Wed, 14 Oct 2020 15:32:26 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Shangyong Shi, Wednesday, October 28, 2020, 3:30PM, on Zoom 92593716884 Message-ID: Meteorology Seminar Shangyong Shi PhD Meteorology Candidate Title: UNDERSTANDING THE PHASES OF PRECIPITATION: CLIMATOLOGY, TRENDS AND PHYSICS OF THE PHASE TRANSITION Major Professor: Guosheng Liu Date: October 28th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/92593716884?pwd=SWdJVUJWVlo4MGgyM09FMDFlQm5Jdz09) ABSTRACT Different phases of precipitation would bring different hydrological impacts. For example, rainfall would become streamflow and increase surface runoffs, while snow would accumulate and increase surface albedo, acting as a crucial driver in the climate system. Therefore, understanding whether precipitation would fall in solid or liquid phase is fundamental to hydrological modeling and forecasting. The precipitation phase is also a critical factor for the surface precipitation retrieval by satellite-based radars, since solid and liquid particles feature different scattering properties and correspond to different relationships between the radar reflectivity and the precipitation rate. With surface temperature warming over the past century, the precipitation phase is expected to shift from solid to liquid, but a global view of the trends has not been established. Moreover, in order to obtain an improved phase classification scheme for satellite snowfall retrieval, it is crucial to investigate the factors that impact the phase transition process and understand the underlying physics. In this thesis, we first investigated the global means and trends of annual precipitation frequency and the ratio of snow events to precipitation events (SE/PE ratio) using land station and shipboard synoptic present weather reports from 1973 to 2019. Results show that when averaged over all qualified land stations, the annual rain frequency and annual snow frequency both have an increasing trend. When averaged over the shipboard reports, the annual rain frequency increases while the annual snow frequency decreases over the 47 years. Over both land and ocean, the averaged SE/PE ratio has a significant decreasing trend. Moreover, the trend of SE/PE ratio shows a strong latitudinal dependence. At the mid and low latitudes in the Northern Hemisphere, the snow frequency increases slower than the rain frequency, and the SE/PE ratio has a decreasing trend. In contrast, at high latitudes, the snow frequency increases faster than the rain frequency, and the SE/PE ratio has an increasing trend. Then, we focused on the physics of the phase transition process. Since the Global Precipitation Measurement (GPM) uses ECMWF Reanalysis Version 5 (ERA5) for their snowfall retrieval, we combined ERA5 with surface observations to investigate the performance of reanalysis dataset in determining precipitation phase. Results based on the station and ship observations were also presented for understanding the physics. The impact of temperature and wet-bulb temperature on the precipitation phase was first examined. On average, the temperature threshold, defined as the conditional probability of snow at 50%, is 1.36?C for land and 1.61?C for ocean based on the ERA5 reanalysis, both around 0.3?C colder than the thresholds derived from observations. The wet-bulb temperature thresholds for land and ocean are 0.72?C and 0.14?C based on the reanalysis, and 0.73?C and 0.83?C for the observations. Using wet-bulb temperature, which incorporates moisture in the calculation, reduces uncertainties in the phase classification. The spatial pattern of the wet-bulb temperature thresholds is also established. Over most of the regions, the wet-bulb temperature threshold falls between 0?C and 1?C. However, this threshold has considerable variations over the globe; derivations from global mean value are particularly large over mountainous areas, coastal regions, and warm ocean currents. Over land, colder wet-bulb temperature thresholds are observed in most high-elevated regions except for the Midwestern U.S., where the thresholds are generally warmer than 2?C. Over ocean, the wet-bulb temperature threshold is colder where there is a warm current, and is warmer at very high latitudes. The influence of different geophysical variables on the precipitation phase was examined. Lapse rate is found to impact the snow conditional probability significantly. At a given wet-bulb temperature, a larger lapse rate leads to a larger conditional probability of snow. In the Midwestern U.S., a smaller pressure would lead to larger snow conditional probability since hydrometeors fall faster in thin air, but this pressure dependence is not evident outside the U.S. For the skin temperature and the difference between the near-surface temperature and skin temperature, there are discrepancies between results based on reanalysis and that based on observations. Further investigation into this issue is expected in the future, in order to develop an improved phase classification scheme based on the reanalysis data. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 15 09:40:06 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 15 Oct 2020 13:40:06 +0000 Subject: [Eoas-seminar] Fw: MET Seminar Series, Thursday, Oct. 15, 2020 at 3:30 PM In-Reply-To: References: Message-ID: Hi all, This is a reminder that Dr. Wanying Kang of MIT will give a MET seminar today at 3:30 PM. The zoom link is https://fsu.zoom.us/j/93591419276?pwd=Q3NrS3hNM2hzNnFVWkFzbWZBeTc1QT09 The detailed information about her seminar can be found in the forwarded email. The pre-seminar social ("meet the speaker") will start at 3:00 PM in the same zoom meeting room. Look forward to seeing you then. Best, Zhaohua ________________________________ From: Eoas-seminar on behalf of eoas-seminar--- via Eoas-seminar Sent: Monday, October 12, 2020 11:42 AM To: EOAS seminar ; seminar at coaps.fsu.edu Cc: Wanying Kang Subject: [Eoas-seminar] MET Seminar Series, Thursday, Oct. 15, 2020 at 3:30 PM Dear colleagues, I am here, on behalf of Drs. Wing and Sura and with great pleasure, to announce that we will have a MET seminar series this semester. The first speaker will be Dr. Wanying Kang of MIT and she will give a talk on Thursday, Oct. 15, 2020 at 3:30 PM. Wanying earned her Ph.D later last year at Harvard University and is currently a MIT distinguished university postdoctoral fellow (https://wanyingkang.com/cv/). She has published extensively in different areas in climate dynamics, including Madden-Julian Oscillation (a well-known tropical phenomena) and its interactions with high latitude and high altitude phenomena, climate dynamics of other planets or moons in and out the solar system. The detailed information of her seminar is here (also see the attached flyer): Title: What shapes Ice Shell of Enceladus? Abstract: Beneath the icy shell encasing Enceladus, a small icy moon of Saturn, a global ocean of liquid water ejects geyser-like sprays into space through fissures concentrated near the south pole, making it one of the places with the highest potential of finding extraterrestrial life. The existence of an ocean has been attributed to the heat generated in dissipative processes associated with the deformation of Enceladus by tidal forcing. However, it remains unclear whether heat is mostly generated in its ice shell or silicate core, and what gives rise to the dramatic asymmetry between the northern and southern hemispheres. Answering these questions is crucial if we are to understand the dynamics behind the active south pole and to unravel patterns of ocean circulation, tracer transport and biosignatures important for the habitability and detectability of potential life. In this presentation, we discuss how we might infer the partition of heat generation between ice shell and core, and demonstrate how the hemispheric asymmetry of ice shell topography could form out of initial random perturbations through mode growth. Time: Thursday, Oct. 15, 2020 at 3:30 PM Zoom Link: https://fsu.zoom.us/j/93591419276?pwd=Q3NrS3hNM2hzNnFVWkFzbWZBeTc1QT09 Please contact me if you want to meet her. Also, the pre-seminar social will start at 3:00 PM that day through the same Zoom Link. Best, Zhaohua -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: MET_Seminar_Flyer_Kang.pdf Type: application/pdf Size: 954560 bytes Desc: MET_Seminar_Flyer_Kang.pdf URL: -------------- next part -------------- _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar From eoas-seminar at lists.fsu.edu Thu Oct 15 17:23:36 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 15 Oct 2020 21:23:36 +0000 Subject: [Eoas-seminar] MET Seminar Series, Thursday, Oct. 15, 2020 at 3:30 PM In-Reply-To: References: Message-ID: I found this commentary ("Solving the puzzle of Enceladus?s active south pole?) published in PNAS about part of the work presented by Wanying Kang today (see attached PDF file). I don?t think I have seen such positive and forward-looking public commentary from a senior scientist (member of National Academy of Sciences) on a research work from a junior scientist. Ming From: Zhaohua Wu Sent: Monday, October 12, 2020 11:42 AM To: EOAS seminar >; seminar at coaps.fsu.edu > Cc: Wanying Kang > Subject: MET Seminar Series, Thursday, Oct. 15, 2020 at 3:30 PM Dear colleagues, I am here, on behalf of Drs. Wing and Sura and with great pleasure, to announce that we will have a MET seminar series this semester. The first speaker will be Dr. Wanying Kang of MIT and she will give a talk on Thursday, Oct. 15, 2020 at 3:30 PM. Wanying earned her Ph.D later last year at Harvard University and is currently a MIT distinguished university postdoctoral fellow (https://wanyingkang.com/cv/). She has published extensively in different areas in climate dynamics, including Madden-Julian Oscillation (a well-known tropical phenomena) and its interactions with high latitude and high altitude phenomena, climate dynamics of other planets or moons in and out the solar system. The detailed information of her seminar is here (also see the attached flyer): Title: What shapes Ice Shell of Enceladus? Abstract: Beneath the icy shell encasing Enceladus, a small icy moon of Saturn, a global ocean of liquid water ejects geyser-like sprays into space through fissures concentrated near the south pole, making it one of the places with the highest potential of finding extraterrestrial life. The existence of an ocean has been attributed to the heat generated in dissipative processes associated with the deformation of Enceladus by tidal forcing. However, it remains unclear whether heat is mostly generated in its ice shell or silicate core, and what gives rise to the dramatic asymmetry between the northern and southern hemispheres. Answering these questions is crucial if we are to understand the dynamics behind the active south pole and to unravel patterns of ocean circulation, tracer transport and biosignatures important for the habitability and detectability of potential life. In this presentation, we discuss how we might infer the partition of heat generation between ice shell and core, and demonstrate how the hemispheric asymmetry of ice shell topography could form out of initial random perturbations through mode growth. Time: Thursday, Oct. 15, 2020 at 3:30 PM Zoom Link: https://fsu.zoom.us/j/93591419276?pwd=Q3NrS3hNM2hzNnFVWkFzbWZBeTc1QT09 Please contact me if you want to meet her. Also, the pre-seminar social will start at 3:00 PM that day through the same Zoom Link. Best, Zhaohua -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: commentary_WY_Kang_icy_moon.pdf Type: application/pdf Size: 579408 bytes Desc: commentary_WY_Kang_icy_moon.pdf URL: From eoas-seminar at lists.fsu.edu Fri Oct 16 16:08:56 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 16 Oct 2020 16:08:56 -0400 Subject: [Eoas-seminar] EOAS Colloquium Friday 10/23 at 3:30 Message-ID: Please join us for our next EOAS Colloquium speaker on Friday Oct 23rd at 3:30 pm via zoom.? Our speaker is Dr. Jonathan Martin of the University of Florida Please see the attached flyer for the title and abstract. The zoom link is: Ming Ye is inviting you to a scheduled Zoom meeting. Topic: EOAS Colloquium by Jonathan Martin from UF Time: Oct 23, 2020 03:30 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/92967597117 Meeting ID: 929 6759 7117 One tap mobile +13017158592,,92967597117# US (Germantown) +13126266799,,92967597117# US (Chicago) If you would like to meet with the speaker please contact Dr Ming Ye to arrange a time. -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 2020Flyer_High Latitude Hydrology.pptx Type: application/vnd.openxmlformats-officedocument.presentationml.presentation Size: 468871 bytes Desc: not available URL: From eoas-seminar at lists.fsu.edu Fri Oct 16 16:22:34 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 16 Oct 2020 16:22:34 -0400 Subject: [Eoas-seminar] Spring Speaker requests Message-ID: Hi Everyone, We are in the window to start planning the spring colloquium.? I am assuming it will be online again.? Please send your speaker suggestions to myself, Zhaohua Wu or Jeremy Owens.? We would also like to include seminars by at least a couple of our own faculty. Please let us know if you would like to volunteer :) This is a good chance to get international speakers we would otherwise not be able to afford to fly here on our speaker budget.? It is also a great opportunity to invite speakers who might be mobility or travel limited. Thanks Amy -- Amy Baco-Taylor, PhD Associate Professor Earth, Ocean, and Atmospheric Sciences Florida State University (850) 645-1547 abacotaylor at fsu.edu NOTE new mailing address: EOAS Building 1011 Academic Way Tallahassee, FL 32306 From eoas-seminar at lists.fsu.edu Sun Oct 18 13:48:49 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Sun, 18 Oct 2020 13:48:49 -0400 Subject: [Eoas-seminar] Upcoming MET Seminars Message-ID: Dear all, Mark your calendars for our upcoming Meteorology seminars! We have an exciting lineup of speakers for the rest of the semester. We have lots of student defenses scheduled between October 26 and November 13, as well as outside speakers scheduled as follows: October 22: Dr. Jane Baldwin (Lamont-Doherty Earth Observatory): "Understanding Tropical Cyclone Risk: from Mountain Drivers to Economic Impacts? November 12: Dr. Catherine Pomposi (USAID): "Understanding recent precipitation variability: from a scientific to a policy and development lens? November 19: Prof. Eric Winsberg (University of South Florida): "Why study solar radiation management? A case study in the cost of acquiring new evidence? December 3: Dr. Ryan Truchelut (WeatherTiger): "From the "Weather Guy" to WeatherTiger: Explorations in Scientific Entrepreneurship? [Check out a sneak preview of WeatherTiger at the 15th TechGrant Elevator Pitch Night on October 21) Each of the above seminars is on a Thursday starting at 3:30 PM, but we will open up the Zoom session at 3:00 PM for informal discussion before the seminar. The seminars are open to the whole department and we hope to see many of you there! Zoom links to follow. Cheers, Allison On behalf of the Meteorology Seminar Committee (Zhaohua Wu, Philip Sura, and myself) ?????????????????? Allison Wing, Ph.D. Assistant Professor Earth, Ocean and Atmospheric Science Florida State University awing at fsu.edu -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 10:10:24 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 14:10:24 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Thomas Gard, Monday, October 26, 2020, 9:00 AM, on Zoom 93507804077 Message-ID: Meteorology Seminar Thomas Gard M.S. Meteorology Candidate Title: Examining the utility of ProbSevere For Predicting Pulse Severe Thunderstorms Major Professor: Dr. Henry Fuelberg Date: Monday, October 26th, 2020 Time: 9:00 AM Location: Zoom Meeting URL: https://fsu.zoom.us/j/93507804077 ABSTRACT Disorganized, weakly forced convection is a routine summertime occurrence in the Southeast United States. Pulse severe storms are single cell thunderstorms that produce severe wind and/or severe hail for a brief period of time. These thunderstorms pose a major warm season forecasting problem, since forecasters presently do not have sufficient guidance to know which, if any, of the many single cells will become severe. The empirical Probability of Severe (ProbSevere) model, developed by the Cooperative Institute for Meteorological Satellite Studies (CIMSS), fuses real-time data to produce short-term, statistically derived probabilistic forecasts of thunderstorm intensity. Objects corresponding to storms are created from satellite and radar data, tracked in two-minute timesteps, and trained on a composite of all modes of severe thunderstorms. ProbSevere has been found to increase forecaster confidence and forecast lead time. However, it is unclear how well ProbSevere performs specifically for pulse severe storms. This study evaluates the ability of ProbSevere to represent and predict pulse severe storms. Pulse severe environments are often classified as being unstable (CAPE * 2000 J kg-1) and weakly sheared (0-6 km AGL shear < 10 m s-1). ProbSevere objects fitting the accepted definition of a pulse severe environment were matched with severe events from Storm Data to create a dataset of ProbSevere objects that corresponded to pulse severe thunderstorms. A null dataset comprised of objects that corresponded to pulse severe environments but did not match with a severe event was also created. Pulse severe objects were evaluated at two times - the time at object initialization and the time of the severe event. This way, the evolution of objects could be analyzed as would be done by a forecaster in real time. Objects were examined in four ways - 1) their temporal evolution, 2) their spatial evolution, 3) how well the severe hail and cellular wind models perform for pulse severe objects, and 4) how well individual predictors discriminate between severe and nonsevere objects. Results reveal that ProbSevere's ability to represent pulse severe thunderstorms is limited, both temporally and spatially. There is little difference between severe hail-producing objects and severe wind-producing objects. At object initialization, ProbSevere exhibits insignificant probabilities of severe weather. At the time of severe events, probabilities are greater but still small. No predictor, with the exception of lightning flash rate, shows a strong correlation with the increasing probability of pulse severe events. Furthermore, no discernable difference in the distribution of probabilities as a function of predictor value is found between severe and nonsevere objects. This study demonstrates that ProbSevere's ability to represent pulse severe thunderstorms is limited, and that ProbSevere is not optimized to give forecasters sufficient guidance for pulse severe storm events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 10:11:33 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 14:11:33 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Fucheng Yang, Tuesday, October 27, 2020, 3:30PM, on Zoom 93626378066 Message-ID: Meteorology Seminar Fucheng Yang M.S. Meteorology Candidate Title: The Origins of Asymmetry in Mid-latitude Annual Cycle Major Professor: Dr. Zhaohua Wu Date: Tuesday, October 27th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/93626378066) ABSTRACT For almost all climate variables, the annual cycle of a climate variable is often the most dominant component of that variable. Although such annual cycle is suggested to tie with the annual changes of the solar irradiance arriving at the top of atmosphere, the detailed physical mechanisms causing the annual cycle remain to be worked out. In this study, we make effort to understand the physical mechanisms behind the observed temporally asymmetric annual cycle of surface air temperature (SAT) over various regions of the Earth. Since the dominant component of the Fourier decomposition of SAT that causes the temporal asymmetry of SAT is its semiannual component, we seek to understand the origins of the semiannual component. We found that, in midlatitudes where the semiannual component of the solar irradiance approaches to zero, the semiannual component of SAT is not directly solar irradiance forced; but rather, it is caused by the annual changes of the heat capacity of the effective surface layer in response to the annual cycle of solar irradiance. We also assess the relative roles of direct forcing and indirect response in generating temporal asymmetry of annual cycle over different regions of the globe. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 10:15:30 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 14:15:30 +0000 Subject: [Eoas-seminar] Oceanography Thesis Defense - Zhou Liang - Nov 2, 1:00pm - Zoom Message-ID: Zhou Liang M.S. Chemical Oceanography Candidate TITLE: THE ENVIRONMENTAL FACTORS INFLUENCING THE ACCUMULATION AND LOSS OF THE DISSOLVED ORGANIC PHOSPHORUS (DOP) IN THE GLOBAL SURFACE OCEAN Major Professor: Dr. Angela Knapp Date: Monday, November 2, 2020 Time: 1:00 PM Location: Zoom Meeting (URL: https://urldefense.com/v3/__https://fsu.zoom.us/j/96954590850?pwd=SVQvSVhQOFp1TmJJQld5blpWWVkydz09__;!!Epnw_ITfSMW4!4KWdO6ij-BSszU6KVbHehNfSoBrJ3nxy-0NcrryyWSmt8kYtPrOvEfolkyMF9w2YFQ$) Meeting ID: 969 5459 0850 Passcode: 676702 ABSTRACT Dissolved organic phosphorus (DOP) in the surface ocean has a dual role as both the product of primary production and as a phosphorus substrate for phytoplankton when inorganic forms of phosphorus (P) are scarce. DOP has increasingly been recognized as an important source of P, especially in oligotrophic gyres, where recent modeling work suggests it may support 8% of net primary production and 33% of biological nitrogen (N2) fixation. However, there are few DOP concentration measurements in the global ocean, especially compared to measurements of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). In particular, there are few DOP concentration measurements from the Indian Ocean and South Pacific Ocean. Consequently, a robust understanding of the role of DOP in supporting primary production and N2 fixation remains data-limited. Here, we present 378 DOP concentration measurements from the 2016 GO-SHIP I08S and I09N cruise in the Eastern Indian Ocean, 204 DOP concentration measurements from the 2017 P06 GO-SHIP cruise in the South Pacific Ocean, and 213 DOP concentration measurements from the 2016 P18 GO-SHIP cruise in the Eastern Pacific Ocean. Additional DOP concentration measurements were made in the Gulf of Alaska (n = 37), South Atlantic (n = 29) and Eastern Tropical South Pacific Ocean (n=119). Together with nitrate+nitrite (NO3), phosphate (PO4), and dissolved organic carbon and nitrogen concentration measurements made in the same samples, we evaluate trends in surface ocean DOP concentration to identify regions of net DOP accumulation and loss. We find that surface ocean DOP stocks are positively correlated with surface ocean chlorophyll a concentration and negatively correlated with iron stress in the Eastern Pacific Ocean, indicating a region of net DOP accumulation. In contrast, surface ocean DOP stocks are negatively correlated with surface ocean chlorophyll a concentration and positively correlated with surface ocean iron stress in the Indian, South Pacific, and Atlantic Oceans, indicating net DOP loss in these regions when iron stress is alleviated. Additionally, surface DOP stocks are significantly negatively correlated with subsurface NO3:PO4 concentration ratios, indicating that PO4 availability plays a key role in regulating surface ocean DOP stocks. Together, these findings significantly expand the global ocean DOP dataset and we provide a mechanism to explain surface ocean DOP distributions, with primary roles for DOP accumulation and loss in the context of phosphate and iron stress in the global scale. -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 11:21:51 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 15:21:51 +0000 Subject: [Eoas-seminar] MET Seminar Series, Thursday, Oct. 22 at 3:30 PM Message-ID: Hi colleagues, This week, MET seminar series will have Dr. Jane Baldwin of Columbia University to give a talk on tropical cyclone risk. The title, abstract, and Zoom Link are given as the following and in the attached flyer: Title: Understanding Tropical Cyclone Risk: from Mountain Drivers to Economic Impacts Abstract: Over the past decade, multiple methods to model tropical cyclones have neared maturity. State-of-the-art global climate models (GCMs) now reach resolutions of 25-50 km in the atmosphere, permitting the simulation of realistic tropical cyclone intensities and tracks. Additionally, statistical-dynamical tropical cyclone models now allow the computationally cheap simulation of many physically plausible tropical cyclones. I will describe recent and ongoing research using these methods to both better understand the drivers of tropical cyclones in different ocean basins, and determine the risks to human society from these extreme events. I will first discuss work using the GCM GFDL CM2.5-FLOR to understand the influence of two different orographic features on the regional climatology of tropical cyclones: 1) the Tibetan Plateau (and related mountains) on the western north Pacific, and 2) the topography of Central America on the eastern tropical Pacific. I will demonstrate the importance of rigorously considering atmosphere-ocean coupling in such analyses, and argue that a relatively small orographic feature can have an outsize climatic influence contingent on its placement relative to the larger-scale circulation. Next I will introduce ongoing work in collaboration with World Bank economists to improve disaster risk assessment using Columbia?s statistical-dynamical tropical cyclone model. I will highlight both challenges and significant opportunities in such hazard to impact modeling. Zoom Link: https://fsu.zoom.us/s/94856469533 There will be a "meet the speaker" at 3:00 PM and a speaker-student session immediately following the seminar. Please join us to enjoy Jane's seminar. Best, Zhaohua More Zoom Link Information: Phone one-tap Phone one-tap: US: +13126266799,,94856469533# or +16465588656,,94856469533# Join by Telephone For higher quality, dial a number based on your current location. Dial: US : +1 312 626 6799 or +1 646 558 8656 or +1 301 715 8592 or +1 346 248 7799 or +1 669 900 9128 or +1 253 215 8782 Meeting ID: 948 5646 9533 International numbers Join from an H.323/SIP room system H.323: 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 948 5646 9533 Passcode: 357490 SIP: 94856469533 at zoomcrc.com Passcode: 357490 -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: MET_Seminar_Flyer_Baldwin.pdf Type: application/pdf Size: 1010570 bytes Desc: MET_Seminar_Flyer_Baldwin.pdf URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 12:05:56 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 16:05:56 +0000 Subject: [Eoas-seminar] Corrected Link: MET Seminar Series, Thursday, Oct. 22 at 3:30 PM - Dr. Jane Baldwin (LDEO) In-Reply-To: References: Message-ID: Dear all, Please use the corrected link below which has the embedded password for Thursday?s MET Seminar at 3:30 PM by Dr. Jane Baldwin (Lamont-Doherty Earth Observatory). Title: Understanding Tropical Cyclone Risk: from Mountain Drivers to Economic Impacts Abstract: Over the past decade, multiple methods to model tropical cyclones have neared maturity. State-of-the-art global climate models (GCMs) now reach resolutions of 25-50 km in the atmosphere, permitting the simulation of realistic tropical cyclone intensities and tracks. Additionally, statistical-dynamical tropical cyclone models now allow the computationally cheap simulation of many physically plausible tropical cyclones. I will describe recent and ongoing research using these methods to both better understand the drivers of tropical cyclones in different ocean basins, and determine the risks to human society from these extreme events. I will first discuss work using the GCM GFDL CM2.5-FLOR to understand the influence of two different orographic features on the regional climatology of tropical cyclones: 1) the Tibetan Plateau (and related mountains) on the western north Pacific, and 2) the topography of Central America on the eastern tropical Pacific. I will demonstrate the importance of rigorously considering atmosphere-ocean coupling in such analyses, and argue that a relatively small orographic feature can have an outsize climatic influence contingent on its placement relative to the larger-scale circulation. Next I will introduce ongoing work in collaboration with World Bank economists to improve disaster risk assessment using Columbia?s statistical-dynamical tropical cyclone model. I will highlight both challenges and significant opportunities in such hazard to impact modeling. *Corrected* Zoom Link: https://fsu.zoom.us/j/94856469533?pwd=aWJBalVhNEUwQ0hCdklGcVRnWGJpUT09 As Zhaohua mentioned, please join us starting from 3 PM to ?meet the speaker? and have informal discussion. GRADUATE STUDENTS: There will be a student Q&A with the speaker to be held immediately following the seminar - so students, please join and stay after the seminar for your chance to talk with Dr. Baldwin about work/life/career topics. Graduate student Jake Carstens will moderate the student Q&A. The seminar will be recorded if you are unable to attend live, but we hope to see many of you there! If anyone would like to meet with Dr. Baldwin earlier in the day or any time after the seminar, you are welcome to get in touch with her (jbaldwin at ldeo.columbia.edu). Cheers, Allison, Zhaohua, & Philip Future MET Seminars: November 12: Dr. Catherine Pomposi (USAID): "Understanding recent precipitation variability: from a scientific to a policy and development lens? November 19: Prof. Eric Winsberg (University of South Florida): "Why study solar radiation management? A case study in the cost of acquiring new evidence? December 3: Dr. Ryan Truchelut (WeatherTiger): "From the "Weather Guy" to WeatherTiger: Explorations in Scientific Entrepreneurship? ?????????????????? Allison Wing, Ph.D. Assistant Professor Earth, Ocean and Atmospheric Science Florida State University awing at fsu.edu _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: MET_Seminar_Flyer_Baldwin.pdf Type: application/pdf Size: 10948643 bytes Desc: MET_Seminar_Flyer_Baldwin.pdf URL: From eoas-seminar at lists.fsu.edu Mon Oct 19 14:17:47 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 19 Oct 2020 18:17:47 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Chesnea Skeen, Monday, November 2, 2020, 9:00 AM, on Zoom 8187403932 Message-ID: Meteorology Seminar Chesnea Skeen M.S. Meteorology Candidate Title: AREA- AND POINT-BASED VERIFICATION OF NEW MULTI-HAZARD SEVERE WEATHER INDEX Major Professor: Dr. Henry Fuelberg Date: November 2nd, 2020 Time: 9:00 AM Location: Zoom meeting URL: https://fsu.zoom.us/j/8187403932 ABSTRACT Severe weather indices are empirical tools developed by meteorologists to assist in predicting severe weather. The Storm Prediction Center's (SPC) Mesoanalysis website lists 23 composite indices. They all are similar in that they calculate differences or combine parameters multiplicatively to determine the severe environment. Most of these indices prioritize a specific weather hazard type or storm convective mode. There is no severe weather index that covers multiple hazards at all severity levels. Lead forecaster Don Van Dyke at the National Weather Service (NWS) Weather Forecast Office (WFO) in Tallahassee aimed to remedy the lack of a holistic index and developed a severe weather index that would encompass three hazards (wind, hail and tornadoes) of any severity. Van Dyke's index (DVDI) also is unique in that it adds its component parameters in the calculations, rather than multiplying them. However, no statistically robust analysis has been conducted on DVDI to show how it performs as a forecasting tool. This research evaluates the skill of DVDI as a forecasting tool, identifies strengths and weaknesses, and suggests improvements. This research conducts a verification of DVDI using combined dichotomous and spatial methods using a point-based and area-based approach. Results show DVDI is able to predict multi-hazard severe weather with an overall POD of 0.78, which suggests DVDI to be a useful forecast tool. DVDI has proven success in predicting all three of the included hazards with a POD of 0.73-0.76. DVDI can differentiate between days with severe weather and days without severe weather with 99% confidence. Additionally, DVDI can distinguish between weak and violent tornadoes with 99% confidence. Weaknesses of DVDI include a high FAR, virtually no skill differentiating hail magnitude, and poor performance with mountainous terrain and winter season wind events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Tue Oct 20 13:10:25 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Tue, 20 Oct 2020 13:10:25 -0400 Subject: [Eoas-seminar] Reminder: Please join us for a seminar by Prof. Dewar on Wednesday October 21 at 10am In-Reply-To: <09f70765-23a8-6483-5019-5e0537a80327@fsu.edu> References: <09f70765-23a8-6483-5019-5e0537a80327@fsu.edu> Message-ID: Eric Chassignet is inviting you to a scheduled Zoom meeting. Topic: Dewar Seminar Time: Oct 21, 2020 10:00 AM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/98539788200 Meeting ID: 985 3978 8200 One tap mobile +13126266799,,98539788200# US (Chicago) +16465588656,,98539788200# US (New York) Dial by your location ??????? +1 312 626 6799 US (Chicago) ??????? +1 646 558 8656 US (New York) ??????? +1 301 715 8592 US (Germantown) ??????? +1 346 248 7799 US (Houston) ??????? +1 669 900 9128 US (San Jose) ??????? +1 253 215 8782 US (Tacoma) Meeting ID: 985 3978 8200 Find your local number: https://fsu.zoom.us/u/accWCcglfU Join by SIP 98539788200 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 985 3978 8200 On 10/8/2020 9:25 AM, Eric Chassignet wrote: > with the catchy title of "Thoughts about things I have been thinking > of late". > The detailed abstract is " There might or might not be something > interesting here. Please help me decide" > Attend at you own risk :-) > > Hope to see you there - will email the zoom link a day before the > seminar. > Best, > Eric > -- Eric Chassignet Professor and Director Center for Ocean-Atmospheric Prediction Studies (COAPS) Florida State University 2000 Levy Avenue, Building A, Suite 292 P.O. Box 3062741 Tallahassee, FL 32306-2741 Office : (1) 850-645-7288 COAPS : (1) 850-644-3846 Cell : (1) 850-524-0033 (urgent matters only) FAX : (1) 850-644-4841 E-mail : echassignet at fsu.edu http://www.coaps.fsu.edu From eoas-seminar at lists.fsu.edu Tue Oct 20 14:15:14 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Tue, 20 Oct 2020 18:15:14 +0000 Subject: [Eoas-seminar] Oceanography Dissertation Defense - Thomas Kelly - Oct 30, noon - Zoom Message-ID: Oceanography Dissertation Defense - Thomas Kelly - Oct 30, noon - Zoom Title: NOT JUST SINKING PARTICLES: EXPORT AND THE BIOLOGICAL CARBON PUMP IN A THREE-DIMENSIONAL OCEAN DRIVEN BY CIRCULATION AND VERTICAL MIGRATION Major Professor: Mike Stukel Join Zoom Meeting https://fsu.zoom.us/j/99842847586 Meeting ID: 998 4284 7586 One tap mobile +16465588656,,99842847586# US (New York) 13017158592,,99842847586# US +(Germantown) Dial by your location ??????? +1 646 558 8656 US (New York) ??????? +1 301 715 8592 US (Germantown) ??????? +1 312 626 6799 US (Chicago) ??????? +1 669 900 9128 US (San Jose) ??????? +1 253 215 8782 US (Tacoma) ??????? +1 346 248 7799 US (Houston) Meeting ID: 998 4284 7586 Find your local number: https://fsu.zoom.us/u/aTPbwnxZg Join by SIP 99842847586 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 998 4284 7586 From eoas-seminar at lists.fsu.edu Wed Oct 21 11:03:08 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Wed, 21 Oct 2020 15:03:08 +0000 Subject: [Eoas-seminar] Geology dissertation defense - Chelsie Bowman - Nov 4, 10am - Zoom Message-ID: Geology dissertation defense - Chelsie Bowman - Nov 4, 10am Title: The coupled evolution of the biosphere and global marine redox conditions in the late Silurian Major Professor: Seth Young Join Zoom Meeting https://fsu.zoom.us/j/92286328718 Meeting ID: 922 8632 8718 Abstract The Silurian was a dynamic time of climatic transition punctuated by multiple biotic crises and global carbon cycle perturbations. The most severe of these biotic crises was the late Silurian (Ludfordian) Lau/Kozlowskii extinction event (LKE; 425 Ma), with a loss of ~23% of marine genera and a resurgence of abiotic and microbially-mediated carbonate facies. The LKE has been recognized as asynchronous for more than a decade, with benthic and nektonic fauna experiencing earlier extinctions than planktic fauna. The LKE preceded and partially coincided with an associated positive carbon isotope excursion, the Lau CIE, which is the highest-magnitude CIE in the Phanerozoic with average peak excursion values between +5 and +8?. It has been suggested, but not directly tested, that both the Lau CIE and the LKE were the result of an expansion of reducing conditions in the Ludfordian global oceans. The mechanisms behind the temporal offset between the extinction and the CIE and the asynchronous nature of the extinction have also not been previously constrained. New records of the extinction and local and global marine paleo-redox change are presented herein from Ludfordian carbonate- and siliciclastic-dominated successions of multiple paleocontinents. For the first time biotic records of well-studied taxonomic groups affected by the LKE are compiled, highlighting the stepwise nature of the extinction. Global paleo-redox dynamics are first examined using a novel approach combining analyses of the stable isotopes of carbon, sulfur, and thallium. A positive excursion in thallium isotopes in the deep-water shales of the Baltic Basin (modern Scandinavia) records the earliest onset of global marine deoxygenation in the Ludfordian, which was coincident with the earliest extinction stages of the LKE and prior to the enhancement of organic carbon burial that fueled the Lau CIE. A large positive excursion in sulfur isotopes in the shallow water carbonates of the Baltic Basin was recorded parallel to the CIE as pyrite burial increased globally. This suggests an expansion of euxinia (anoxic and sulfidic water column) in the global oceans following the initial deoxygenation and concurrent with the later extinction stages of the LKE. Support for the expansion of reducing conditions in the late Silurian global oceans comes from the study of carbonate successions along the southern and western margins of the paleocontinent Laurentia (modern North America) where paired positive excursions in carbon and sulfur isotopes lend further evidence for the global enhancement of organic carbon and pyrite burial. Variability in local and regional paleo-redox dynamics in the Ludfordian have been explored along the southern Laurentian margin and in the Baltic and Prague basins. Low I/Ca ratios from the carbonates of southern Laurentia and the shallow shelf of the Baltic Basin indicate proximity to local/regional oxygen minimum zones (OMZ) concurrent with the global expansion of reducing conditions. High pyrite content in the carbonate strata of southern Laurentia and the Prague Basin (peri-Gondwanan terrane; modern Czech Republic) suggest that sulfidic sediment porewaters were common. Comparison of iron geochemistry and trace metal enrichments in the deep shelf of the Baltic Basin to that of modern OMZs imply that the basin may have been dominated by a nitrogenous OMZ throughout most of the Ludfordian. There is also a possible overprint of a global trace metal drawdown in the stratigraphic trends of trace metal enrichments from this locality that would have been coeval with the enhancement of pyrite burial and the expansion of euxinic conditions in the global oceans. Dynamics of the LKE event have been further explored through microfacies analyses and accounts of previously unreported microbially-mediated facies in Ludfordian carbonate successions. The LKE event is recorded in southern Laurentia as notable biotic reorganizations during the interval of the mid-Ludfordian when reducing conditions would have been the most prevalent in the global ocean. Flat-pebble conglomerate facies and possible microbial mats are reported from the carbonate strata of western Laurentia and the Prague Basin, ooids and micro-oncoids from southern Laurentia. The variety and pervasiveness of microbially-mediated carbonate facies associated with the LKE hint at the severity of the extinction and the restructuring of faunal communities that took place within carbonate platforms during the Ludfordian. Altogether, the geochemical, biotic, and lithologic data presented here represent the first proxy evidence linking the LKE event to the Lau CIE through the progressive expansion of anoxia, and later euxinia, across portions of the late Silurian oceans. This multi-proxy, multi-lithology approach provides a previously unmatched, holistic view of the dramatic changes in the late Silurian marine biosphere and global marine redox conditions. -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Wed Oct 21 11:29:46 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Wed, 21 Oct 2020 15:29:46 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Shangyong Shi, Wednesday, October 28, 2020, 3:30PM, on Zoom 92593716884 Message-ID: Meteorology Seminar Shangyong Shi PhD Meteorology Candidate Title: UNDERSTANDING THE PHASES OF PRECIPITATION: CLIMATOLOGY, TRENDS AND PHYSICS OF THE PHASE TRANSITION Major Professor: Guosheng Liu Date: October 28th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/92593716884?pwd=SWdJVUJWVlo4MGgyM09FMDFlQm5Jdz09) ABSTRACT Different phases of precipitation would bring different hydrological impacts. For example, rainfall would become streamflow and increase surface runoffs, while snow would accumulate and increase surface albedo, acting as a crucial driver in the climate system. Therefore, understanding whether precipitation would fall in solid or liquid phase is fundamental to hydrological modeling and forecasting. The precipitation phase is also a critical factor for the surface precipitation retrieval by satellite-based radars, since solid and liquid particles feature different scattering properties and correspond to different relationships between the radar reflectivity and the precipitation rate. With surface temperature warming over the past century, the precipitation phase is expected to shift from solid to liquid, but a global view of the trends has not been established. Moreover, in order to obtain an improved phase classification scheme for satellite snowfall retrieval, it is crucial to investigate the factors that impact the phase transition process and understand the underlying physics. In this thesis, we first investigated the global means and trends of annual precipitation frequency and the ratio of snow events to precipitation events (SE/PE ratio) using land station and shipboard synoptic present weather reports from 1973 to 2019. Results show that when averaged over all qualified land stations, the annual rain frequency and annual snow frequency both have an increasing trend. When averaged over the shipboard reports, the annual rain frequency increases while the annual snow frequency decreases over the 47 years. Over both land and ocean, the averaged SE/PE ratio has a significant decreasing trend. Moreover, the trend of SE/PE ratio shows a strong latitudinal dependence. At the mid and low latitudes in the Northern Hemisphere, the snow frequency increases slower than the rain frequency, and the SE/PE ratio has a decreasing trend. In contrast, at high latitudes, the snow frequency increases faster than the rain frequency, and the SE/PE ratio has an increasing trend. Then, we focused on the physics of the phase transition process. Since the Global Precipitation Measurement (GPM) uses ECMWF Reanalysis Version 5 (ERA5) for their snowfall retrieval, we combined ERA5 with surface observations to investigate the performance of reanalysis dataset in determining precipitation phase. Results based on the station and ship observations were also presented for understanding the physics. The impact of temperature and wet-bulb temperature on the precipitation phase was first examined. On average, the temperature threshold, defined as the conditional probability of snow at 50%, is 1.36?C for land and 1.61?C for ocean based on the ERA5 reanalysis, both around 0.3?C colder than the thresholds derived from observations. The wet-bulb temperature thresholds for land and ocean are 0.72?C and 0.14?C based on the reanalysis, and 0.73?C and 0.83?C for the observations. Using wet-bulb temperature, which incorporates moisture in the calculation, reduces uncertainties in the phase classification. The spatial pattern of the wet-bulb temperature thresholds is also established. Over most of the regions, the wet-bulb temperature threshold falls between 0?C and 1?C. However, this threshold has considerable variations over the globe; derivations from global mean value are particularly large over mountainous areas, coastal regions, and warm ocean currents. Over land, colder wet-bulb temperature thresholds are observed in most high-elevated regions except for the Midwestern U.S., where the thresholds are generally warmer than 2?C. Over ocean, the wet-bulb temperature threshold is colder where there is a warm current, and is warmer at very high latitudes. The influence of different geophysical variables on the precipitation phase was examined. Lapse rate is found to impact the snow conditional probability significantly. At a given wet-bulb temperature, a larger lapse rate leads to a larger conditional probability of snow. In the Midwestern U.S., a smaller pressure would lead to larger snow conditional probability since hydrometeors fall faster in thin air, but this pressure dependence is not evident outside the U.S. For the skin temperature and the difference between the near-surface temperature and skin temperature, there are discrepancies between results based on reanalysis and that based on observations. Further investigation into this issue is expected in the future, in order to develop an improved phase classification scheme based on the reanalysis data. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 22 09:19:58 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 22 Oct 2020 13:19:58 +0000 Subject: [Eoas-seminar] Reminder: MET seminar today at 3:30 PM by Dr. Jane Baldwin (Lamont-Doherty Earth Observatory) Message-ID: Dear all, Please use the corrected link below which has the embedded password for Thursday?s MET Seminar at 3:30 PM by Dr. Jane Baldwin (Lamont-Doherty Earth Observatory). Title: Understanding Tropical Cyclone Risk: from Mountain Drivers to Economic Impacts Abstract: Over the past decade, multiple methods to model tropical cyclones have neared maturity. State-of-the-art global climate models (GCMs) now reach resolutions of 25-50 km in the atmosphere, permitting the simulation of realistic tropical cyclone intensities and tracks. Additionally, statistical-dynamical tropical cyclone models now allow the computationally cheap simulation of many physically plausible tropical cyclones. I will describe recent and ongoing research using these methods to both better understand the drivers of tropical cyclones in different ocean basins, and determine the risks to human society from these extreme events. I will first discuss work using the GCM GFDL CM2.5-FLOR to understand the influence of two different orographic features on the regional climatology of tropical cyclones: 1) the Tibetan Plateau (and related mountains) on the western north Pacific, and 2) the topography of Central America on the eastern tropical Pacific. I will demonstrate the importance of rigorously considering atmosphere-ocean coupling in such analyses, and argue that a relatively small orographic feature can have an outsize climatic influence contingent on its placement relative to the larger-scale circulation. Next I will introduce ongoing work in collaboration with World Bank economists to improve disaster risk assessment using Columbia?s statistical-dynamical tropical cyclone model. I will highlight both challenges and significant opportunities in such hazard to impact modeling. *Corrected* Zoom Link: https://fsu.zoom.us/j/94856469533?pwd=aWJBalVhNEUwQ0hCdklGcVRnWGJpUT09 As Zhaohua mentioned, please join us starting from 3 PM to ?meet the speaker? and have informal discussion. GRADUATE STUDENTS: There will be a student Q&A with the speaker to be held immediately following the seminar - so students, please join and stay after the seminar for your chance to talk with Dr. Baldwin about work/life/career topics. Graduate student Jake Carstens will moderate the student Q&A. The seminar will be recorded if you are unable to attend live, but we hope to see many of you there! If anyone would like to meet with Dr. Baldwin earlier in the day or any time after the seminar, you are welcome to get in touch with her (jbaldwin at ldeo.columbia.edu). Cheers, Allison, Zhaohua, & Philip Future MET Seminars: November 12: Dr. Catherine Pomposi (USAID): "Understanding recent precipitation variability: from a scientific to a policy and development lens? November 19: Prof. Eric Winsberg (University of South Florida): "Why study solar radiation management? A case study in the cost of acquiring new evidence? December 3: Dr. Ryan Truchelut (WeatherTiger): "From the "Weather Guy" to WeatherTiger: Explorations in Scientific Entrepreneurship? -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 22 10:13:08 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 22 Oct 2020 14:13:08 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Catherine Buczek, Monday, November 5th, 2020, 3:30 PM, on Zoom Message-ID: Meteorology Seminar Catherine R, Buczek M.S. Meteorology Candidate Title: USING MULTI-DIMENSIONAL ENSEMBLE EMPIRICAL MODEL DECOMPOSITION (MEEMD) TO DIAGNOSE CHANGES IN THE NORTHERN HEMISPHERE ANNUAL CYCLE Major Professor: Dr. Zhaohua Wu Date: November 5th, 2020 Time: 3:30 PM Location: Zoom ABSTRACT The annual cycle is a relatively large-scale climate process which influences smaller scale climate and meteorological processes. The goal of this research is to diagnose changes to the Northern Hemisphere annual cycle from 1949 to 2017 using multi-dimensional ensemble empirical mode decomposition (MEEMD). MEEMD is a newer decomposition method that is built on empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD; Wu et al. 2009). Compared to EMD and EEMD, MEEMD can be used to decompose spatiotemporal data sets making climate research easier, which often relies heavily on gridded data sets (Wu et al. 2016). In this study, MEEMD is applied to 2-meter pentad temperature data from the National Centers for Environmental Prediction (NCEP)/National Centers for Atmospheric Research (NCAR) Reanalysis 1 (Kalnay et al., 1996) to obtain the amplitude trend of the annual cycle. The amplitude trend of the annual cycle for all points are normalized to compare the trends between polar and tropical latitudes, as the polar latitudes are changing at a more rapid rate than the tropical latitudes, likely due to anthropogenic forcing (IPCC 2019). Results show that the annual cycle is decreasing in polar latitudes and increasing in tropical latitudes. In mid-latitudes, the annual cycle appears to change depending on topography where, in general, the annual cycle is decreasing in highland regions and increasing in lowland regions. Changes in climate modes may also play a role in mid-latitude results but this remains to be studied in depth. Identifying changes to the annual cycle will prove useful for understanding the spatially differing effects of climate change on weather and climate in the Northern Hemisphere. The results of this research serve as a diagnosis and open the opportunity for future research to explain the results of this paper. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 22 11:11:53 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 22 Oct 2020 15:11:53 +0000 Subject: [Eoas-seminar] CORRECTION: Meteorology MS Defense for Catherine Buczek, Thursday, November 5th, 2020, 3:30 PM, on Zoom Message-ID: Meteorology Seminar Catherine R. Buczek M.S. Meteorology Candidate Title: USING MULTI-DIMENSIONAL ENSEMBLE EMPIRICAL MODEL DECOMPOSITION (MEEMD) TO DIAGNOSE CHANGES IN THE NORTHERN HEMISPHERE ANNUAL CYCLE Major Professor: Dr. Zhaohua Wu Date: November 5th, 2020 Time: 3:30 PM Location: Zoom ABSTRACT The annual cycle is a relatively large-scale climate process which influences smaller scale climate and meteorological processes. The goal of this research is to diagnose changes to the Northern Hemisphere annual cycle from 1949 to 2017 using multi-dimensional ensemble empirical mode decomposition (MEEMD). MEEMD is a newer decomposition method that is built on empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD; Wu et al. 2009). Compared to EMD and EEMD, MEEMD can be used to decompose spatiotemporal data sets making climate research easier, which often relies heavily on gridded data sets (Wu et al. 2016). In this study, MEEMD is applied to 2-meter pentad temperature data from the National Centers for Environmental Prediction (NCEP)/National Centers for Atmospheric Research (NCAR) Reanalysis 1 (Kalnay et al., 1996) to obtain the amplitude trend of the annual cycle. The amplitude trend of the annual cycle for all points are normalized to compare the trends between polar and tropical latitudes, as the polar latitudes are changing at a more rapid rate than the tropical latitudes, likely due to anthropogenic forcing (IPCC 2019). Results show that the annual cycle is decreasing in polar latitudes and increasing in tropical latitudes. In mid-latitudes, the annual cycle appears to change depending on topography where, in general, the annual cycle is decreasing in highland regions and increasing in lowland regions. Changes in climate modes may also play a role in mid-latitude results but this remains to be studied in depth. Identifying changes to the annual cycle will prove useful for understanding the spatially differing effects of climate change on weather and climate in the Northern Hemisphere. The results of this research serve as a diagnosis and open the opportunity for future research to explain the results of this paper. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 22 19:26:56 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 22 Oct 2020 23:26:56 +0000 Subject: [Eoas-seminar] Reminder: MET seminar today at 3:30 PM by Dr. Jane Baldwin (Lamont-Doherty Earth Observatory) In-Reply-To: References: Message-ID: Thanks to those who attended todays MET seminar. If you were unable to attend and would like to view the recording, please contact me (awing at fsu.edu). ????????????????? Allison Wing, Ph.D. Assistant Professor Earth, Ocean and Atmospheric Science Florida State University awing at fsu.edu On Oct 22, 2020, at 9:19 AM, eoas-seminar--- via Eoas-seminar > wrote: Dear all, Please use the corrected link below which has the embedded password for Thursday?s MET Seminar at 3:30 PM by Dr. Jane Baldwin (Lamont-Doherty Earth Observatory). Title: Understanding Tropical Cyclone Risk: from Mountain Drivers to Economic Impacts Abstract: Over the past decade, multiple methods to model tropical cyclones have neared maturity. State-of-the-art global climate models (GCMs) now reach resolutions of 25-50 km in the atmosphere, permitting the simulation of realistic tropical cyclone intensities and tracks. Additionally, statistical-dynamical tropical cyclone models now allow the computationally cheap simulation of many physically plausible tropical cyclones. I will describe recent and ongoing research using these methods to both better understand the drivers of tropical cyclones in different ocean basins, and determine the risks to human society from these extreme events. I will first discuss work using the GCM GFDL CM2.5-FLOR to understand the influence of two different orographic features on the regional climatology of tropical cyclones: 1) the Tibetan Plateau (and related mountains) on the western north Pacific, and 2) the topography of Central America on the eastern tropical Pacific. I will demonstrate the importance of rigorously considering atmosphere-ocean coupling in such analyses, and argue that a relatively small orographic feature can have an outsize climatic influence contingent on its placement relative to the larger-scale circulation. Next I will introduce ongoing work in collaboration with World Bank economists to improve disaster risk assessment using Columbia?s statistical-dynamical tropical cyclone model. I will highlight both challenges and significant opportunities in such hazard to impact modeling. *Corrected* Zoom Link: https://fsu.zoom.us/j/94856469533?pwd=aWJBalVhNEUwQ0hCdklGcVRnWGJpUT09 As Zhaohua mentioned, please join us starting from 3 PM to ?meet the speaker? and have informal discussion. GRADUATE STUDENTS: There will be a student Q&A with the speaker to be held immediately following the seminar - so students, please join and stay after the seminar for your chance to talk with Dr. Baldwin about work/life/career topics. Graduate student Jake Carstens will moderate the student Q&A. The seminar will be recorded if you are unable to attend live, but we hope to see many of you there! If anyone would like to meet with Dr. Baldwin earlier in the day or any time after the seminar, you are welcome to get in touch with her (jbaldwin at ldeo.columbia.edu). Cheers, Allison, Zhaohua, & Philip Future MET Seminars: November 12: Dr. Catherine Pomposi (USAID): "Understanding recent precipitation variability: from a scientific to a policy and development lens? November 19: Prof. Eric Winsberg (University of South Florida): "Why study solar radiation management? A case study in the cost of acquiring new evidence? December 3: Dr. Ryan Truchelut (WeatherTiger): "From the "Weather Guy" to WeatherTiger: Explorations in Scientific Entrepreneurship? _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Fri Oct 23 08:37:13 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 23 Oct 2020 08:37:13 -0400 Subject: [Eoas-seminar] REMINDER TODAY - Fwd: EOAS Colloquium Friday 10/23 at 3:30 In-Reply-To: References: Message-ID: Please join us for our next EOAS Colloquium speaker on TODAY at 3:30 pm via zoom.? Our speaker is Dr. Jonathan Martin of the University of Florida Please see the attached flyer for the title and abstract. The zoom link is: Ming Ye is inviting you to a scheduled Zoom meeting. Topic: EOAS Colloquium by Jonathan Martin from UF Time: Oct 23, 2020 03:30 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/92967597117 Meeting ID: 929 6759 7117 One tap mobile +13017158592,,92967597117# US (Germantown) +13126266799,,92967597117# US (Chicago) If you would like to meet with the speaker please contact Dr Ming Ye to arrange a time. -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 2020Flyer_High Latitude Hydrology.pptx Type: application/vnd.openxmlformats-officedocument.presentationml.presentation Size: 468871 bytes Desc: not available URL: -------------- next part -------------- _______________________________________________ Eoas-seminar mailing list Eoas-seminar at lists.fsu.edu https://lists.fsu.edu/mailman/listinfo/eoas-seminar From eoas-seminar at lists.fsu.edu Fri Oct 23 09:53:58 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 23 Oct 2020 13:53:58 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Michael Secor, Friday, November 6, 2020, 11:00 AM, on Zoom Message-ID: Meteorology Seminar Michael Secor M.S. Meteorology Candidate Title: how global warming and topography have impacted the amplitude of synoptic Temperature variability Major Professor: Dr. Zhaohua Wu Date: November 6th, 2020 Time: 11:00 AM Location: Zoom Meeting ABSTRACT Synoptic scale drivers, mainly extra-tropical cyclones, account for a majority of the day to day temperature variability in the mid-latitudes. This variability is at its greatest in the Northern Hemisphere in Boreal winter when the surface meridional temperature gradient is strong. Global warming has led to a reduction of the surface meridional temperature gradient due to the phenomenon of Arctic Amplification, where the Arctic has been warming at a faster rate than the mid-latitudes or tropics. Changes to the surface meridional temperature gradient will likely alter the baroclinicity of the mid-latitudes and thus extra-tropical cyclones. Understanding how extra-tropical cyclones and their associated temperature variability change in the presence of warming is vital to mitigating the potential outcomes such as an increased chance of heatwaves in regions with reduced variability or an increased chance of cold snaps that could negatively impact farmers in regions of increased variability. Using complementary ensemble empirical mode decomposition (CEEMD) to isolate the synoptic component of daily mean surface temperature, the evolution of the trend of synoptic temperature variability is analyzed. There has been a spatial in-homogeneity of synoptic temperature variability change ranging from -36.5% to 39.2% from 1948-2018 over the continental United States, Northern Mexico, and surrounding oceans. This variability is also temporally non-uniform. The first three decades experienced relatively large decadal rates of change, followed by a two-decade lull, where large regions experienced a reversal in the direction of synoptic temperature variability change. The last two decades have maintained the spatial structure observed in 1998 with the regions expanding in size and changing more quickly with time. Higher altitudes and surrounding regions generally see an increase in variability while elsewhere over land a reduction is observed. This creates a three-band structure over the continental United States. Averaged over the entire domain, an increase in variability in excess of 6% is observed below 30N while a reduction of 4.25% is observed above 30N. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: image001.png Type: image/png Size: 210 bytes Desc: image001.png URL: From eoas-seminar at lists.fsu.edu Fri Oct 23 13:03:17 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 23 Oct 2020 17:03:17 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Thomas Gard, Monday, October 26, 2020, 9:00 AM, on Zoom https://fsu.zoom.us/j/93507804077?pwd=UmVweThlUHJVQjBwaTR0ZmR2Q1g5QT09 Message-ID: NOTE: The zoom link has been updated. Please use this link on Monday. Meteorology Seminar Thomas Gard M.S. Meteorology Candidate Title: Examining the utility of ProbSevere For Predicting Pulse Severe Thunderstorms Major Professor: Dr. Henry Fuelberg Date: Monday, October 26th, 2020 Time: 9:00 AM Location: Zoom Meeting URL: https://fsu.zoom.us/j/93507804077?pwd=UmVweThlUHJVQjBwaTR0ZmR2Q1g5QT09 ABSTRACT Disorganized, weakly forced convection is a routine summertime occurrence in the Southeast United States. Pulse severe storms are single cell thunderstorms that produce severe wind and/or severe hail for a brief period of time. These thunderstorms pose a major warm season forecasting problem, since forecasters presently do not have sufficient guidance to know which, if any, of the many single cells will become severe. The empirical Probability of Severe (ProbSevere) model, developed by the Cooperative Institute for Meteorological Satellite Studies (CIMSS), fuses real-time data to produce short-term, statistically derived probabilistic forecasts of thunderstorm intensity. Objects corresponding to storms are created from satellite and radar data, tracked in two-minute timesteps, and trained on a composite of all modes of severe thunderstorms. ProbSevere has been found to increase forecaster confidence and forecast lead time. However, it is unclear how well ProbSevere performs specifically for pulse severe storms. This study evaluates the ability of ProbSevere to represent and predict pulse severe storms. Pulse severe environments are often classified as being unstable (CAPE * 2000 J kg-1) and weakly sheared (0-6 km AGL shear < 10 m s-1). ProbSevere objects fitting the accepted definition of a pulse severe environment were matched with severe events from Storm Data to create a dataset of ProbSevere objects that corresponded to pulse severe thunderstorms. A null dataset comprised of objects that corresponded to pulse severe environments but did not match with a severe event was also created. Pulse severe objects were evaluated at two times - the time at object initialization and the time of the severe event. This way, the evolution of objects could be analyzed as would be done by a forecaster in real time. Objects were examined in four ways - 1) their temporal evolution, 2) their spatial evolution, 3) how well the severe hail and cellular wind models perform for pulse severe objects, and 4) how well individual predictors discriminate between severe and nonsevere objects. Results reveal that ProbSevere's ability to represent pulse severe thunderstorms is limited, both temporally and spatially. There is little difference between severe hail-producing objects and severe wind-producing objects. At object initialization, ProbSevere exhibits insignificant probabilities of severe weather. At the time of severe events, probabilities are greater but still small. No predictor, with the exception of lightning flash rate, shows a strong correlation with the increasing probability of pulse severe events. Furthermore, no discernable difference in the distribution of probabilities as a function of predictor value is found between severe and nonsevere objects. This study demonstrates that ProbSevere's ability to represent pulse severe thunderstorms is limited, and that ProbSevere is not optimized to give forecasters sufficient guidance for pulse severe storm events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 26 08:06:48 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 26 Oct 2020 12:06:48 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Thomas Gard, Monday, October 26, 2020, 9:00 AM, on Zoom https://fsu.zoom.us/j/93507804077?pwd=UmVweThlUHJVQjBwaTR0ZmR2Q1g5QT09 Message-ID: NOTE: The zoom link has been updated. Please use this link on Monday. Meteorology Seminar Thomas Gard M.S. Meteorology Candidate Title: Examining the utility of ProbSevere For Predicting Pulse Severe Thunderstorms Major Professor: Dr. Henry Fuelberg Date: Monday, October 26th, 2020 Time: 9:00 AM Location: Zoom Meeting URL: https://fsu.zoom.us/j/93507804077?pwd=UmVweThlUHJVQjBwaTR0ZmR2Q1g5QT09 ABSTRACT Disorganized, weakly forced convection is a routine summertime occurrence in the Southeast United States. Pulse severe storms are single cell thunderstorms that produce severe wind and/or severe hail for a brief period of time. These thunderstorms pose a major warm season forecasting problem, since forecasters presently do not have sufficient guidance to know which, if any, of the many single cells will become severe. The empirical Probability of Severe (ProbSevere) model, developed by the Cooperative Institute for Meteorological Satellite Studies (CIMSS), fuses real-time data to produce short-term, statistically derived probabilistic forecasts of thunderstorm intensity. Objects corresponding to storms are created from satellite and radar data, tracked in two-minute timesteps, and trained on a composite of all modes of severe thunderstorms. ProbSevere has been found to increase forecaster confidence and forecast lead time. However, it is unclear how well ProbSevere performs specifically for pulse severe storms. This study evaluates the ability of ProbSevere to represent and predict pulse severe storms. Pulse severe environments are often classified as being unstable (CAPE * 2000 J kg-1) and weakly sheared (0-6 km AGL shear < 10 m s-1). ProbSevere objects fitting the accepted definition of a pulse severe environment were matched with severe events from Storm Data to create a dataset of ProbSevere objects that corresponded to pulse severe thunderstorms. A null dataset comprised of objects that corresponded to pulse severe environments but did not match with a severe event was also created. Pulse severe objects were evaluated at two times - the time at object initialization and the time of the severe event. This way, the evolution of objects could be analyzed as would be done by a forecaster in real time. Objects were examined in four ways - 1) their temporal evolution, 2) their spatial evolution, 3) how well the severe hail and cellular wind models perform for pulse severe objects, and 4) how well individual predictors discriminate between severe and nonsevere objects. Results reveal that ProbSevere's ability to represent pulse severe thunderstorms is limited, both temporally and spatially. There is little difference between severe hail-producing objects and severe wind-producing objects. At object initialization, ProbSevere exhibits insignificant probabilities of severe weather. At the time of severe events, probabilities are greater but still small. No predictor, with the exception of lightning flash rate, shows a strong correlation with the increasing probability of pulse severe events. Furthermore, no discernable difference in the distribution of probabilities as a function of predictor value is found between severe and nonsevere objects. This study demonstrates that ProbSevere's ability to represent pulse severe thunderstorms is limited, and that ProbSevere is not optimized to give forecasters sufficient guidance for pulse severe storm events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 26 08:32:26 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 26 Oct 2020 12:32:26 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Fucheng Yang, Tuesday, October 27, 2020, 3:30PM, on Zoom 93626378066 Message-ID: Meteorology Seminar Fucheng Yang M.S. Meteorology Candidate Title: The Origins of Asymmetry in Mid-latitude Annual Cycle Major Professor: Dr. Zhaohua Wu Date: Tuesday, October 27th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/93626378066) ABSTRACT For almost all climate variables, the annual cycle of a climate variable is often the most dominant component of that variable. Although such annual cycle is suggested to tie with the annual changes of the solar irradiance arriving at the top of atmosphere, the detailed physical mechanisms causing the annual cycle remain to be worked out. In this study, we make effort to understand the physical mechanisms behind the observed temporally asymmetric annual cycle of surface air temperature (SAT) over various regions of the Earth. Since the dominant component of the Fourier decomposition of SAT that causes the temporal asymmetry of SAT is its semiannual component, we seek to understand the origins of the semiannual component. We found that, in midlatitudes where the semiannual component of the solar irradiance approaches to zero, the semiannual component of SAT is not directly solar irradiance forced; but rather, it is caused by the annual changes of the heat capacity of the effective surface layer in response to the annual cycle of solar irradiance. We also assess the relative roles of direct forcing and indirect response in generating temporal asymmetry of annual cycle over different regions of the globe. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 26 08:33:43 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 26 Oct 2020 12:33:43 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Chesnea Skeen, Monday, November 2, 2020, 9:00 AM, on Zoom 8187403932 Message-ID: Meteorology Seminar Chesnea Skeen M.S. Meteorology Candidate Title: AREA- AND POINT-BASED VERIFICATION OF NEW MULTI-HAZARD SEVERE WEATHER INDEX Major Professor: Dr. Henry Fuelberg Date: November 2nd, 2020 Time: 9:00 AM Location: Zoom meeting URL: https://fsu.zoom.us/j/8187403932 ABSTRACT Severe weather indices are empirical tools developed by meteorologists to assist in predicting severe weather. The Storm Prediction Center's (SPC) Mesoanalysis website lists 23 composite indices. They all are similar in that they calculate differences or combine parameters multiplicatively to determine the severe environment. Most of these indices prioritize a specific weather hazard type or storm convective mode. There is no severe weather index that covers multiple hazards at all severity levels. Lead forecaster Don Van Dyke at the National Weather Service (NWS) Weather Forecast Office (WFO) in Tallahassee aimed to remedy the lack of a holistic index and developed a severe weather index that would encompass three hazards (wind, hail and tornadoes) of any severity. Van Dyke's index (DVDI) also is unique in that it adds its component parameters in the calculations, rather than multiplying them. However, no statistically robust analysis has been conducted on DVDI to show how it performs as a forecasting tool. This research evaluates the skill of DVDI as a forecasting tool, identifies strengths and weaknesses, and suggests improvements. This research conducts a verification of DVDI using combined dichotomous and spatial methods using a point-based and area-based approach. Results show DVDI is able to predict multi-hazard severe weather with an overall POD of 0.78, which suggests DVDI to be a useful forecast tool. DVDI has proven success in predicting all three of the included hazards with a POD of 0.73-0.76. DVDI can differentiate between days with severe weather and days without severe weather with 99% confidence. Additionally, DVDI can distinguish between weak and violent tornadoes with 99% confidence. Weaknesses of DVDI include a high FAR, virtually no skill differentiating hail magnitude, and poor performance with mountainous terrain and winter season wind events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Mon Oct 26 10:09:08 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Mon, 26 Oct 2020 10:09:08 -0400 Subject: [Eoas-seminar] EOAS Colloquium Speaker Friday Oct 30 at 3:30 In-Reply-To: References: Message-ID: Please join us on zoom for this week's colloquium speaker on Friday Oct 30th at 3:30 pm: Dr. Rhys Parfitt, of EOAS, FSU *Does the extra-tropical ocean significantly impact mid-latitude weather and climate?* The answer to this question remains somewhat controversial within the atmospheric and oceanic communities. In the first half of the talk, I provide a review of the general arguments made for and against the oceanic role and summarize why there has been a strong resurgence in research interest in recent years. In the second half, I propose a new framework that I believe resolves many open questions from the past decade and shows that the extra-tropical ocean is indeed critical in shaping both mid-latitude weather and climate. ----------------------- Topic: EOAS Seminar 30th October Time: Oct 30, 2020 03:30 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/99882607273 Meeting ID: 998 8260 7273 -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Tue Oct 27 10:58:43 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Tue, 27 Oct 2020 14:58:43 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Fucheng Yang, Tuesday, October 27, 2020, 3:30PM, on Zoom 93626378066 Message-ID: Meteorology Seminar Fucheng Yang M.S. Meteorology Candidate Title: The Origins of Asymmetry in Mid-latitude Annual Cycle Major Professor: Dr. Zhaohua Wu Date: Tuesday, October 27th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/93626378066) ABSTRACT For almost all climate variables, the annual cycle of a climate variable is often the most dominant component of that variable. Although such annual cycle is suggested to tie with the annual changes of the solar irradiance arriving at the top of atmosphere, the detailed physical mechanisms causing the annual cycle remain to be worked out. In this study, we make effort to understand the physical mechanisms behind the observed temporally asymmetric annual cycle of surface air temperature (SAT) over various regions of the Earth. Since the dominant component of the Fourier decomposition of SAT that causes the temporal asymmetry of SAT is its semiannual component, we seek to understand the origins of the semiannual component. We found that, in midlatitudes where the semiannual component of the solar irradiance approaches to zero, the semiannual component of SAT is not directly solar irradiance forced; but rather, it is caused by the annual changes of the heat capacity of the effective surface layer in response to the annual cycle of solar irradiance. We also assess the relative roles of direct forcing and indirect response in generating temporal asymmetry of annual cycle over different regions of the globe. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Wed Oct 28 09:10:12 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Wed, 28 Oct 2020 13:10:12 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Shangyong Shi, Wednesday, October 28, 2020, 3:30PM, on Zoom 92593716884 Message-ID: Meteorology Seminar Shangyong Shi PhD Meteorology Candidate Title: UNDERSTANDING THE PHASES OF PRECIPITATION: CLIMATOLOGY, TRENDS AND PHYSICS OF THE PHASE TRANSITION Major Professor: Guosheng Liu Date: October 28th, 2020 Time: 3:30 PM Location: Zoom Meeting (URL: https://fsu.zoom.us/j/92593716884?pwd=SWdJVUJWVlo4MGgyM09FMDFlQm5Jdz09) ABSTRACT Different phases of precipitation would bring different hydrological impacts. For example, rainfall would become streamflow and increase surface runoffs, while snow would accumulate and increase surface albedo, acting as a crucial driver in the climate system. Therefore, understanding whether precipitation would fall in solid or liquid phase is fundamental to hydrological modeling and forecasting. The precipitation phase is also a critical factor for the surface precipitation retrieval by satellite-based radars, since solid and liquid particles feature different scattering properties and correspond to different relationships between the radar reflectivity and the precipitation rate. With surface temperature warming over the past century, the precipitation phase is expected to shift from solid to liquid, but a global view of the trends has not been established. Moreover, in order to obtain an improved phase classification scheme for satellite snowfall retrieval, it is crucial to investigate the factors that impact the phase transition process and understand the underlying physics. In this thesis, we first investigated the global means and trends of annual precipitation frequency and the ratio of snow events to precipitation events (SE/PE ratio) using land station and shipboard synoptic present weather reports from 1973 to 2019. Results show that when averaged over all qualified land stations, the annual rain frequency and annual snow frequency both have an increasing trend. When averaged over the shipboard reports, the annual rain frequency increases while the annual snow frequency decreases over the 47 years. Over both land and ocean, the averaged SE/PE ratio has a significant decreasing trend. Moreover, the trend of SE/PE ratio shows a strong latitudinal dependence. At the mid and low latitudes in the Northern Hemisphere, the snow frequency increases slower than the rain frequency, and the SE/PE ratio has a decreasing trend. In contrast, at high latitudes, the snow frequency increases faster than the rain frequency, and the SE/PE ratio has an increasing trend. Then, we focused on the physics of the phase transition process. Since the Global Precipitation Measurement (GPM) uses ECMWF Reanalysis Version 5 (ERA5) for their snowfall retrieval, we combined ERA5 with surface observations to investigate the performance of reanalysis dataset in determining precipitation phase. Results based on the station and ship observations were also presented for understanding the physics. The impact of temperature and wet-bulb temperature on the precipitation phase was first examined. On average, the temperature threshold, defined as the conditional probability of snow at 50%, is 1.36?C for land and 1.61?C for ocean based on the ERA5 reanalysis, both around 0.3?C colder than the thresholds derived from observations. The wet-bulb temperature thresholds for land and ocean are 0.72?C and 0.14?C based on the reanalysis, and 0.73?C and 0.83?C for the observations. Using wet-bulb temperature, which incorporates moisture in the calculation, reduces uncertainties in the phase classification. The spatial pattern of the wet-bulb temperature thresholds is also established. Over most of the regions, the wet-bulb temperature threshold falls between 0?C and 1?C. However, this threshold has considerable variations over the globe; derivations from global mean value are particularly large over mountainous areas, coastal regions, and warm ocean currents. Over land, colder wet-bulb temperature thresholds are observed in most high-elevated regions except for the Midwestern U.S., where the thresholds are generally warmer than 2?C. Over ocean, the wet-bulb temperature threshold is colder where there is a warm current, and is warmer at very high latitudes. The influence of different geophysical variables on the precipitation phase was examined. Lapse rate is found to impact the snow conditional probability significantly. At a given wet-bulb temperature, a larger lapse rate leads to a larger conditional probability of snow. In the Midwestern U.S., a smaller pressure would lead to larger snow conditional probability since hydrometeors fall faster in thin air, but this pressure dependence is not evident outside the U.S. For the skin temperature and the difference between the near-surface temperature and skin temperature, there are discrepancies between results based on reanalysis and that based on observations. Further investigation into this issue is expected in the future, in order to develop an improved phase classification scheme based on the reanalysis data. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Wed Oct 28 10:00:32 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Wed, 28 Oct 2020 14:00:32 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Darin Mister, Monday, November 9, 2020, 3:30 PM on Zoom Message-ID: Meteorology Seminar Darin Mister M.S. Meteorology Candidate TITLE: THE IMPACT OF SURFACE OCEAN CURRENTS ON TURBULENT HEAT FLUXES GENERATED BY ATLANTIC EXTRATROPICAL CYCLONES Major Professor: Dr. Mark Bourassa Date: November 9th, 2020 Time: 3:30 PM Location: Zoom meeting ABSTRACT Extratropical cyclones are responsible for the generation of large amounts of latent and sensible heat fluxes over the ocean. These fluxes are the main mechanism by which the ocean influences the atmosphere. Extratropical cyclones that form in the Atlantic interact with the relatively warm western boundary current known as the Gulf Stream. Surface currents in the Gulf Stream are much faster than the surrounding ocean. Previous studies have shown that including ocean currents in the calculation of fluxes can cause latent and sensible heat flux to change. Ocean and atmospheric reanalysis of extratropical cyclones from 1994-2015 are used to study the impacts that surface ocean currents can have on the latent and sensible heat fluxes generated by extratropical cyclones. Fluxes are calculated using a method developed by Kara et al. (2000) and the effect of the current is represented by replacing the 10m windspeed used in the calculation with the magnitude of the vector difference between the windspeed and the current speed: i.e., using surface relative winds rather than Earth relative winds. Changes are widely variable but typical changes are 10-30 Wm-1 for both sensible and latent heat flux. The largest changes in flux occurred in areas of highest current, but that change is dependent on other factors such as windspeed, air-sea temperature difference, and air-sea humidity difference. Currents can impact flux gradients depending on the locations of greatest changes. It was found that the impact of currents will result in decreased flux values in the cold sector of extratropical cyclones (the area where the greatest magnitudes of flux are produced). This study shows the importance of accurately representing the ocean in models of weather and climate. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 29 09:18:03 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 29 Oct 2020 13:18:03 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Catherine Buczek, Thursday, November 5th, 2020, 3:30 PM, on Zoom Message-ID: Meteorology Seminar Catherine R. Buczek M.S. Meteorology Candidate Title: USING MULTI-DIMENSIONAL ENSEMBLE EMPIRICAL MODEL DECOMPOSITION (MEEMD) TO DIAGNOSE CHANGES IN THE NORTHERN HEMISPHERE ANNUAL CYCLE Major Professor: Dr. Zhaohua Wu Date: November 5th, 2020 Time: 3:30 PM Location: Zoom ABSTRACT The annual cycle is a relatively large-scale climate process which influences smaller scale climate and meteorological processes. The goal of this research is to diagnose changes to the Northern Hemisphere annual cycle from 1949 to 2017 using multi-dimensional ensemble empirical mode decomposition (MEEMD). MEEMD is a newer decomposition method that is built on empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD; Wu et al. 2009). Compared to EMD and EEMD, MEEMD can be used to decompose spatiotemporal data sets making climate research easier, which often relies heavily on gridded data sets (Wu et al. 2016). In this study, MEEMD is applied to 2-meter pentad temperature data from the National Centers for Environmental Prediction (NCEP)/National Centers for Atmospheric Research (NCAR) Reanalysis 1 (Kalnay et al., 1996) to obtain the amplitude trend of the annual cycle. The amplitude trend of the annual cycle for all points are normalized to compare the trends between polar and tropical latitudes, as the polar latitudes are changing at a more rapid rate than the tropical latitudes, likely due to anthropogenic forcing (IPCC 2019). Results show that the annual cycle is decreasing in polar latitudes and increasing in tropical latitudes. In mid-latitudes, the annual cycle appears to change depending on topography where, in general, the annual cycle is decreasing in highland regions and increasing in lowland regions. Changes in climate modes may also play a role in mid-latitude results but this remains to be studied in depth. Identifying changes to the annual cycle will prove useful for understanding the spatially differing effects of climate change on weather and climate in the Northern Hemisphere. The results of this research serve as a diagnosis and open the opportunity for future research to explain the results of this paper. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Thu Oct 29 13:31:13 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Thu, 29 Oct 2020 17:31:13 +0000 Subject: [Eoas-seminar] Reminder: Oceanography Dissertation Defense - Thomas Kelly - Oct 30, noon - Zoom Message-ID: Oceanography Dissertation Defense - Thomas Kelly - Oct 30, noon - Zoom Title: NOT JUST SINKING PARTICLES: EXPORT AND THE BIOLOGICAL CARBON PUMP IN A THREE-DIMENSIONAL OCEAN DRIVEN BY CIRCULATION AND VERTICAL MIGRATION Major Professor: Mike Stukel Join Zoom Meeting https://fsu.zoom.us/j/99842847586 Meeting ID: 998 4284 7586 One tap mobile +16465588656,,99842847586# US (New York) 13017158592,,99842847586# US +(Germantown) Dial by your location ??????? +1 646 558 8656 US (New York) ??????? +1 301 715 8592 US (Germantown) ??????? +1 312 626 6799 US (Chicago) ??????? +1 669 900 9128 US (San Jose) ??????? +1 253 215 8782 US (Tacoma) ??????? +1 346 248 7799 US (Houston) Meeting ID: 998 4284 7586 Find your local number: https://fsu.zoom.us/u/aTPbwnxZg Join by SIP 99842847586 at zoomcrc.com Join by H.323 162.255.37.11 (US West) 162.255.36.11 (US East) 115.114.131.7 (India Mumbai) 115.114.115.7 (India Hyderabad) 213.19.144.110 (Amsterdam Netherlands) 213.244.140.110 (Germany) 103.122.166.55 (Australia) 149.137.40.110 (Singapore) 64.211.144.160 (Brazil) 69.174.57.160 (Canada) 207.226.132.110 (Japan) Meeting ID: 998 4284 7586 From eoas-seminar at lists.fsu.edu Fri Oct 30 09:58:14 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 30 Oct 2020 09:58:14 -0400 Subject: [Eoas-seminar] REMINDER TODAY - Fwd: EOAS Colloquium Speaker Friday Oct 30 at 3:30 In-Reply-To: References: Message-ID: Please join us on zoom for this week's colloquium speaker TODAY at 3:30 pm: Dr. Rhys Parfitt, of EOAS, FSU *Does the extra-tropical ocean significantly impact mid-latitude weather and climate?* The answer to this question remains somewhat controversial within the atmospheric and oceanic communities. In the first half of the talk, I provide a review of the general arguments made for and against the oceanic role and summarize why there has been a strong resurgence in research interest in recent years. In the second half, I propose a new framework that I believe resolves many open questions from the past decade and shows that the extra-tropical ocean is indeed critical in shaping both mid-latitude weather and climate. ----------------------- Topic: EOAS Seminar 30th October Time: Oct 30, 2020 03:30 PM Eastern Time (US and Canada) Join Zoom Meeting https://fsu.zoom.us/j/99882607273 Meeting ID: 998 8260 7273 -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Fri Oct 30 10:01:15 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 30 Oct 2020 14:01:15 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Michael Secor, Friday, November 6, 2020, 11:00 AM, on Zoom Message-ID: Meteorology Seminar Michael Secor M.S. Meteorology Candidate TITLE: HOW GLOBAL WARMING AND TOPOGRAPHY HAVE IMPACTED THE AMPLITUDE OF SYNOPTIC TEMPERATURE VARIABILITY Major Professor: Dr. Zhaohua Wu Date: November 6th, 2020 Time: 11:00 AM Location: Zoom Meeting ABSTRACT Synoptic scale drivers, mainly extra-tropical cyclones, account for a majority of the day to day temperature variability in the mid-latitudes. This variability is at its greatest in the Northern Hemisphere in Boreal winter when the surface meridional temperature gradient is strong. Global warming has led to a reduction of the surface meridional temperature gradient due to the phenomenon of Arctic Amplification, where the Arctic has been warming at a faster rate than the mid-latitudes or tropics. Changes to the surface meridional temperature gradient will likely alter the baroclinicity of the mid-latitudes and thus extra-tropical cyclones. Understanding how extra-tropical cyclones and their associated temperature variability change in the presence of warming is vital to mitigating the potential outcomes such as an increased chance of heatwaves in regions with reduced variability or an increased chance of cold snaps that could negatively impact farmers in regions of increased variability. Using complementary ensemble empirical mode decomposition (CEEMD) to isolate the synoptic component of daily mean surface temperature, the evolution of the trend of synoptic temperature variability is analyzed. There has been a spatial in-homogeneity of synoptic temperature variability change ranging from -36.5% to 39.2% from 1948-2018 over the continental United States, Northern Mexico, and surrounding oceans. This variability is also temporally non-uniform. The first three decades experienced relatively large decadal rates of change, followed by a two-decade lull, where large regions experienced a reversal in the direction of synoptic temperature variability change. The last two decades have maintained the spatial structure observed in 1998 with the regions expanding in size and changing more quickly with time. Higher altitudes and surrounding regions generally see an increase in variability while elsewhere over land a reduction is observed. This creates a three-band structure over the continental United States. Averaged over the entire domain, an increase in variability in excess of 6% is observed below 30[cid:2fb6ee43-0d3c-4e89-b81b-422fc4a00e0e]N while a reduction of 4.25% is observed above 30[cid:da459aba-0027-457f-ba84-16c63190ff09]N. -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: pastedImagebase640.png Type: image/png Size: 136 bytes Desc: pastedImagebase640.png URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: pastedImagebase641.png Type: image/png Size: 136 bytes Desc: pastedImagebase641.png URL: From eoas-seminar at lists.fsu.edu Fri Oct 30 12:57:45 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 30 Oct 2020 16:57:45 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Chesnea Skeen, Monday, November 2, 2020, 9:00 AM, on Zoom 8187403932 Message-ID: Meteorology Seminar Chesnea Skeen M.S. Meteorology Candidate Title: AREA- AND POINT-BASED VERIFICATION OF NEW MULTI-HAZARD SEVERE WEATHER INDEX Major Professor: Dr. Henry Fuelberg Date: November 2nd, 2020 Time: 9:00 AM Location: Zoom meeting URL: https://fsu.zoom.us/j/8187403932 ABSTRACT Severe weather indices are empirical tools developed by meteorologists to assist in predicting severe weather. The Storm Prediction Center's (SPC) Mesoanalysis website lists 23 composite indices. They all are similar in that they calculate differences or combine parameters multiplicatively to determine the severe environment. Most of these indices prioritize a specific weather hazard type or storm convective mode. There is no severe weather index that covers multiple hazards at all severity levels. Lead forecaster Don Van Dyke at the National Weather Service (NWS) Weather Forecast Office (WFO) in Tallahassee aimed to remedy the lack of a holistic index and developed a severe weather index that would encompass three hazards (wind, hail and tornadoes) of any severity. Van Dyke's index (DVDI) also is unique in that it adds its component parameters in the calculations, rather than multiplying them. However, no statistically robust analysis has been conducted on DVDI to show how it performs as a forecasting tool. This research evaluates the skill of DVDI as a forecasting tool, identifies strengths and weaknesses, and suggests improvements. This research conducts a verification of DVDI using combined dichotomous and spatial methods using a point-based and area-based approach. Results show DVDI is able to predict multi-hazard severe weather with an overall POD of 0.78, which suggests DVDI to be a useful forecast tool. DVDI has proven success in predicting all three of the included hazards with a POD of 0.73-0.76. DVDI can differentiate between days with severe weather and days without severe weather with 99% confidence. Additionally, DVDI can distinguish between weak and violent tornadoes with 99% confidence. Weaknesses of DVDI include a high FAR, virtually no skill differentiating hail magnitude, and poor performance with mountainous terrain and winter season wind events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Fri Oct 30 15:33:58 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 30 Oct 2020 19:33:58 +0000 Subject: [Eoas-seminar] Reminder: Oceanography Thesis Defense - Zhou Liang - Nov 2, 1:00pm - Zoom Message-ID: Zhou Liang M.S. Chemical Oceanography Candidate TITLE: THE ENVIRONMENTAL FACTORS INFLUENCING THE ACCUMULATION AND LOSS OF THE DISSOLVED ORGANIC PHOSPHORUS (DOP) IN THE GLOBAL SURFACE OCEAN Major Professor: Dr. Angela Knapp Date: Monday, November 2, 2020 Time: 1:00 PM Location: Zoom Meeting (URL: https://urldefense.com/v3/__https://fsu.zoom.us/j/96954590850?pwd=SVQvSVhQOFp1TmJJQld5blpWWVkydz09__;!!Epnw_ITfSMW4!4KWdO6ij-BSszU6KVbHehNfSoBrJ3nxy-0NcrryyWSmt8kYtPrOvEfolkyMF9w2YFQ$) Meeting ID: 969 5459 0850 Passcode: 676702 ABSTRACT Dissolved organic phosphorus (DOP) in the surface ocean has a dual role as both the product of primary production and as a phosphorus substrate for phytoplankton when inorganic forms of phosphorus (P) are scarce. DOP has increasingly been recognized as an important source of P, especially in oligotrophic gyres, where recent modeling work suggests it may support 8% of net primary production and 33% of biological nitrogen (N2) fixation. However, there are few DOP concentration measurements in the global ocean, especially compared to measurements of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). In particular, there are few DOP concentration measurements from the Indian Ocean and South Pacific Ocean. Consequently, a robust understanding of the role of DOP in supporting primary production and N2 fixation remains data-limited. Here, we present 378 DOP concentration measurements from the 2016 GO-SHIP I08S and I09N cruise in the Eastern Indian Ocean, 204 DOP concentration measurements from the 2017 P06 GO-SHIP cruise in the South Pacific Ocean, and 213 DOP concentration measurements from the 2016 P18 GO-SHIP cruise in the Eastern Pacific Ocean. Additional DOP concentration measurements were made in the Gulf of Alaska (n = 37), South Atlantic (n = 29) and Eastern Tropical South Pacific Ocean (n=119). Together with nitrate+nitrite (NO3), phosphate (PO4), and dissolved organic carbon and nitrogen concentration measurements made in the same samples, we evaluate trends in surface ocean DOP concentration to identify regions of net DOP accumulation and loss. We find that surface ocean DOP stocks are positively correlated with surface ocean chlorophyll a concentration and negatively correlated with iron stress in the Eastern Pacific Ocean, indicating a region of net DOP accumulation. In contrast, surface ocean DOP stocks are negatively correlated with surface ocean chlorophyll a concentration and positively correlated with surface ocean iron stress in the Indian, South Pacific, and Atlantic Oceans, indicating net DOP loss in these regions when iron stress is alleviated. Additionally, surface DOP stocks are significantly negatively correlated with subsurface NO3:PO4 concentration ratios, indicating that PO4 availability plays a key role in regulating surface ocean DOP stocks. Together, these findings significantly expand the global ocean DOP dataset and we provide a mechanism to explain surface ocean DOP distributions, with primary roles for DOP accumulation and loss in the context of phosphate and iron stress in the global scale. -------------- next part -------------- An HTML attachment was scrubbed... URL: From eoas-seminar at lists.fsu.edu Fri Oct 30 15:45:16 2020 From: eoas-seminar at lists.fsu.edu (eoas-seminar at lists.fsu.edu) Date: Fri, 30 Oct 2020 19:45:16 +0000 Subject: [Eoas-seminar] Meteorology MS Defense for Chesnea Skeen, Monday, November 2, 2020, 9:00 AM, on Zoom 8187403932 Message-ID: Meteorology Seminar Chesnea Skeen M.S. Meteorology Candidate Title: AREA- AND POINT-BASED VERIFICATION OF NEW MULTI-HAZARD SEVERE WEATHER INDEX Major Professor: Dr. Henry Fuelberg Date: November 2nd, 2020 Time: 9:00 AM Location: Zoom meeting URL: https://fsu.zoom.us/j/8187403932 ABSTRACT Severe weather indices are empirical tools developed by meteorologists to assist in predicting severe weather. The Storm Prediction Center's (SPC) Mesoanalysis website lists 23 composite indices. They all are similar in that they calculate differences or combine parameters multiplicatively to determine the severe environment. Most of these indices prioritize a specific weather hazard type or storm convective mode. There is no severe weather index that covers multiple hazards at all severity levels. Lead forecaster Don Van Dyke at the National Weather Service (NWS) Weather Forecast Office (WFO) in Tallahassee aimed to remedy the lack of a holistic index and developed a severe weather index that would encompass three hazards (wind, hail and tornadoes) of any severity. Van Dyke's index (DVDI) also is unique in that it adds its component parameters in the calculations, rather than multiplying them. However, no statistically robust analysis has been conducted on DVDI to show how it performs as a forecasting tool. This research evaluates the skill of DVDI as a forecasting tool, identifies strengths and weaknesses, and suggests improvements. This research conducts a verification of DVDI using combined dichotomous and spatial methods using a point-based and area-based approach. Results show DVDI is able to predict multi-hazard severe weather with an overall POD of 0.78, which suggests DVDI to be a useful forecast tool. DVDI has proven success in predicting all three of the included hazards with a POD of 0.73-0.76. DVDI can differentiate between days with severe weather and days without severe weather with 99% confidence. Additionally, DVDI can distinguish between weak and violent tornadoes with 99% confidence. Weaknesses of DVDI include a high FAR, virtually no skill differentiating hail magnitude, and poor performance with mountainous terrain and winter season wind events. Shel McGuire Florida State University Academic Program Specialist Department of Earth, Ocean, & Atmospheric Science 1011 Academic Way, 2019 EOA Building Tallahassee, FL 32306 850-644-8582 To make an appointment please login to my.fsu.edu and choose the Campus Connect (CC) icon -------------- next part -------------- An HTML attachment was scrubbed... URL: