The 19th Workshop on Antarctic Meteorology and Climate(WAMC)and the 8th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)meeting were held in June 2024 at the Byrd Polar and Climate Research Center,The Ohio...The 19th Workshop on Antarctic Meteorology and Climate(WAMC)and the 8th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)meeting were held in June 2024 at the Byrd Polar and Climate Research Center,The Ohio State University,Columbus,Ohio.These hybrid events convened 79 participants from 15 nations to foster international collaboration on Antarctic meteorology,climate research,and forecasting.The WAMC featured presentations on automatic weather stations,numerical weather prediction,Antarctic sea ice dynamics,and extreme weather events.The YOPP-SH meeting emphasized the positive impacts of enhanced observations during the 2022 Winter Special Observing Period(SOP)on forecast accuracy and addressed the transition toward the Polar Coupled Analysis and Prediction for Services(PCAPS)initiative.The outcomes reflect significant advancements in polar meteorological research and underscore the importance of sustained collaborative efforts,including improved observational networks and advanced modeling systems,to address the unique challenges of Antarctic meteorology.Future workshops will continue to support and expand upon these critical themes.展开更多
The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of W...The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of Wisconsin-Madison in Madison,WI,USA.Global members of the Antarctic meteorological community gathered to present and discuss topics from scientific research to operational support within Antarctic meteorology and climate.Students and early career professionals chaired various presentations and discussions while all attendees engaged to share results,build collaborative plans,and discuss further developments.The main workshop topics included updates on the current Automatic Weather Station(AWS)networks,challenges,and planning concerning Antarctic forecasting and operational services,Antarctic numerical modeling systems,observational applications and research,and Antarctic community and data sources.Across six sessions,over 25 different presenters elaborated on their work in areas such as field season updates,atmospheric rivers,remote sensing,the Antarctic Mesoscale Prediction System(AMPS),and forecasting challenges due to data scarcity.Workshop discussions resulted in several key outcomes and action items regarding fieldwork impacts,exploration of field techniques,observation coverage,and communication between operations and research scientists.Future workshops will provide opportunities for continued discussion on the evolution of the AWS network and operational needs while providing a venue to promote collaboration and cooperation for Antarctic meteorology and climate activities.展开更多
Presented is a review of the radiative properties of ice clouds from three perspectives： light scattering simulations, remote sensing applications, and broadband radiation parameterizations appropriate for numerical ...Presented is a review of the radiative properties of ice clouds from three perspectives： light scattering simulations, remote sensing applications, and broadband radiation parameterizations appropriate for numerical models. On the subject of light scattering simulations, several classical computational approaches are reviewed, including the conventional geometric-optics method and its improved forms, the finite-difference time domain technique, the pseudo-spectral time domain technique, the discrete dipole approximation method, and the T-matrix method, with specific applications to the computation of the singlescattering properties of individual ice crystals. The strengths and weaknesses associated with each approach are discussed.With reference to remote sensing, operational retrieval algorithms are reviewed for retrieving cloud optical depth and effective particle size based on solar or thermal infrared（IR） bands. To illustrate the performance of the current solar- and IR-based retrievals, two case studies are presented based on spaceborne observations. The need for a more realistic ice cloud optical model to obtain spectrally consistent retrievals is demonstrated. Furthermore, to complement ice cloud property studies based on passive radiometric measurements, the advantage of incorporating lidar and/or polarimetric measurements is discussed.The performance of ice cloud models based on the use of different ice habits to represent ice particles is illustrated by comparing model results with satellite observations. A summary is provided of a number of parameterization schemes for ice cloud radiative properties that were developed for application to broadband radiative transfer submodels within general circulation models（GCMs）. The availability of the single-scattering properties of complex ice habits has led to more accurate radiation parameterizations. In conclusion, the importance of using nonspherical ice particle models in GCM simulations for climate studies is proven.展开更多
Linearization of Radiative Transfer Equation (RTE) is the key step in physical retrieval of atmospheric temperature and moisture profiles from InfRared (IR) sounder observations. In this paper, the successive forms of...Linearization of Radiative Transfer Equation (RTE) is the key step in physical retrieval of atmospheric temperature and moisture profiles from InfRared (IR) sounder observations. In this paper, the successive forms of temperature and water vapor mixing ratio component weighting functions are derived by applying one term variation method to RTE with surface emissivity and solar reflectivity contained. Retrivals of temperature and water vapor mixing ratio profiles from simulated Atmospheric Infrared Sounder (AIRS) observations with surface emissivity and solar reflectivity are presented.展开更多
1.Overview The 12th Workshop on Antarctic Meteorology and Climate（WAMC）,formerly known as the Antarctic Meteorological Observation,Modeling,and Forecasting（AMOMF）Workshop（AMOMFW）,was held at the National Center ...1.Overview The 12th Workshop on Antarctic Meteorology and Climate（WAMC）,formerly known as the Antarctic Meteorological Observation,Modeling,and Forecasting（AMOMF）Workshop（AMOMFW）,was held at the National Center for Atmospheric Research（NCAR）in Boulder,Colorado,USA on 26–28 June 2017.The annual workshop dates from 2006,and recent meetings have been the 10th AMOMF Workshop held in 2015 in Cambridge,展开更多
1. Overview The 10th Antarctic Meteorological Observation, Modeling, and Forecasting Workshop （hereinafter AMOMFW） took place June 17-19, 2015 in the historic city of Cambridge, United Kingdom. The meeting followed...1. Overview The 10th Antarctic Meteorological Observation, Modeling, and Forecasting Workshop （hereinafter AMOMFW） took place June 17-19, 2015 in the historic city of Cambridge, United Kingdom. The meeting followed its purpose of connecting Antarctic atmospheric science to weatherrelated operational issues and advances in observing, modeling, forecasting, and understanding the Antarctic environment.展开更多
1.Overview August 2022 marked the 17th Workshop on Antarctic Meteorology and Climate(WAMC)which was held in a hybrid format at the Pyle Center at the University of Wisconsin-Madison(UW-Madison)in Madison,WI,USA.The wo...1.Overview August 2022 marked the 17th Workshop on Antarctic Meteorology and Climate(WAMC)which was held in a hybrid format at the Pyle Center at the University of Wisconsin-Madison(UW-Madison)in Madison,WI,USA.The workshop is the first partial in-person gathering since the 14th WAMC(Lazzara et al.,2018)as the 15th WAMC was canceled due to the COVID-19 pandemic,and the 16th WAMC(Bromwich et al.,2022)was purely online.Global members of the Antarctic meteorological community gathered at this meeting to present and discuss weather-related topics encompassing scientific research and support operations within Antarctic meteorology and climate.These conversations aimed to share and discuss results,future developments,and build collaborative plans.展开更多
1.Overview In July 2018,the Antarctic community came together to meet at the 13th Workshop on Antarctic Meteorology and Climate(WAMC)in Madison,Wisconsin,USA(Fig.1);and in the following year in June 2019,the 14th WAMC...1.Overview In July 2018,the Antarctic community came together to meet at the 13th Workshop on Antarctic Meteorology and Climate(WAMC)in Madison,Wisconsin,USA(Fig.1);and in the following year in June 2019,the 14th WAMC was held in Charleston,South Carolina,USA(Fig.2).With a growing history,the WAMC addresses the topics of Antarctic meteorology and climate(Kameda et al.,2008;Colwell et al.,2016;Lazzara et al.,2018)as well as weather-related issues of scientific and operational support.The workshops bring together researchers,operational forecasters,numerical modelers,observational specialists,and students.The themes of both workshops included Antarctic meteorological observations,Antarctic atmospheric numerical modeling,Antarctic meteorological and climate research,and Antarctic weather forecasting and operational services.The 2018 and 2019 WAMC were both followed by a one-day focus on the Year of Polar Prediction-Southern Hemisphere(YOPP-SH),when preparations and follow-up discussions were made with regard to the YOPP Special Observing Period from 16 November 2018 to 15 February 2019.展开更多
Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Ai...Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely impacted.Specifically,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the aircraft.The cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low temperatures.Four separate cold phases were identified,each a few days in duration and occurring from mid-July to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold temperatures.The monthly 500-hPa geopotential height anomalies show strong negative anomalies in August.Examination of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric conditions.Understanding the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology.展开更多
1.Overview In June 2021,the 16th Workshop on Antarctic Meteorology and Climate(WAMC)and the 6th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)Meeting(http://polarmet.osu.edu/WAMC;021/)were held online an...1.Overview In June 2021,the 16th Workshop on Antarctic Meteorology and Climate(WAMC)and the 6th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)Meeting(http://polarmet.osu.edu/WAMC;021/)were held online and hosted by the Polar Meteorology Group at Byrd Polar and Climate Research Center,The Ohio State University,Columbus,Ohio(Fig.1).展开更多
To estimate sea surface temperature(SST)with high accuracy from radiometrie measure- ments,it is no longer acceptable to assume that sea surface emissivity is unity or any other con- stant.This note presents an invest...To estimate sea surface temperature(SST)with high accuracy from radiometrie measure- ments,it is no longer acceptable to assume that sea surface emissivity is unity or any other con- stant.This note presents an investigation of the desirable emissivity accuracy in relation to re- trieval.It was found that 1% error in surface emissivity can cause up to 0.7 K error in the re- trieved SST,although this sensitivity is often reduced to about 0.5 K on average because of the downward atmospheric radiation at surface partially compensates for the emissivity error.Since the downward atmospheric radiation ratio is controlled to a large extent by the integrated water vapor in the atmosphere and,secondarily,by view angle,the sensitivity of SST retrieval to surface emis- sivity has been computed as a function of these two parameters.展开更多
Despite decades of theoretical research and observational studies, a good understanding of tropical cyclone genesis(TCG) remains elusive. One school of theories proposes that TCG within an African Easterly Wave result...Despite decades of theoretical research and observational studies, a good understanding of tropical cyclone genesis(TCG) remains elusive. One school of theories proposes that TCG within an African Easterly Wave results from “bottom-up” development of cyclonic vorticity that is contingent upon favorable conditions in the lower-troposphere and boundary layer. Our observational study suggests that while lower-tropospheric forcing is a necessary condition for this type of TCG, it may not be sufficient in some cases, and that environmental conditions in the upper levels can have an influence. Specifically, we find evidence to suggest that pre-TCG upper-tropospheric flow patterns characterized by core-connecting outflow vents to the environment can in certain situations provide a modulating effect on Atlantic tropical disturbances trying to develop. Patterns of nearenvironment upper-level inertial stability, divergence, outflow setup, and mass evacuation are identified and related to surface development. The study employs high-resolution satellite-derived wind data, aircraft GPS dropwindsondes, composite fields, multivariate objective analyses, and case studies to help identify conditions in the upper-level environment that can play a role in Atlantic TCG events.展开更多
基金support from the Office of Polar Programs of the National Science Foundation(Grant Nos.2205398,2233182,1951720,1951603,2301362).
文摘The 19th Workshop on Antarctic Meteorology and Climate(WAMC)and the 8th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)meeting were held in June 2024 at the Byrd Polar and Climate Research Center,The Ohio State University,Columbus,Ohio.These hybrid events convened 79 participants from 15 nations to foster international collaboration on Antarctic meteorology,climate research,and forecasting.The WAMC featured presentations on automatic weather stations,numerical weather prediction,Antarctic sea ice dynamics,and extreme weather events.The YOPP-SH meeting emphasized the positive impacts of enhanced observations during the 2022 Winter Special Observing Period(SOP)on forecast accuracy and addressed the transition toward the Polar Coupled Analysis and Prediction for Services(PCAPS)initiative.The outcomes reflect significant advancements in polar meteorological research and underscore the importance of sustained collaborative efforts,including improved observational networks and advanced modeling systems,to address the unique challenges of Antarctic meteorology.Future workshops will continue to support and expand upon these critical themes.
基金the support from the Office of Polar Programs,National Science Foundation(Grant Nos.1924730,1951720,1951603,and 2205398),which is greatly appreciated.
文摘The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of Wisconsin-Madison in Madison,WI,USA.Global members of the Antarctic meteorological community gathered to present and discuss topics from scientific research to operational support within Antarctic meteorology and climate.Students and early career professionals chaired various presentations and discussions while all attendees engaged to share results,build collaborative plans,and discuss further developments.The main workshop topics included updates on the current Automatic Weather Station(AWS)networks,challenges,and planning concerning Antarctic forecasting and operational services,Antarctic numerical modeling systems,observational applications and research,and Antarctic community and data sources.Across six sessions,over 25 different presenters elaborated on their work in areas such as field season updates,atmospheric rivers,remote sensing,the Antarctic Mesoscale Prediction System(AMPS),and forecasting challenges due to data scarcity.Workshop discussions resulted in several key outcomes and action items regarding fieldwork impacts,exploration of field techniques,observation coverage,and communication between operations and research scientists.Future workshops will provide opportunities for continued discussion on the evolution of the AWS network and operational needs while providing a venue to promote collaboration and cooperation for Antarctic meteorology and climate activities.
基金supported by the NSF (Grants AGS-1338440 and AGS-0946315)the endowment funds related to the David Bullock Harris Chair in Geosciences at the College of Geosciences, Texas A&M University
文摘Presented is a review of the radiative properties of ice clouds from three perspectives： light scattering simulations, remote sensing applications, and broadband radiation parameterizations appropriate for numerical models. On the subject of light scattering simulations, several classical computational approaches are reviewed, including the conventional geometric-optics method and its improved forms, the finite-difference time domain technique, the pseudo-spectral time domain technique, the discrete dipole approximation method, and the T-matrix method, with specific applications to the computation of the singlescattering properties of individual ice crystals. The strengths and weaknesses associated with each approach are discussed.With reference to remote sensing, operational retrieval algorithms are reviewed for retrieving cloud optical depth and effective particle size based on solar or thermal infrared（IR） bands. To illustrate the performance of the current solar- and IR-based retrievals, two case studies are presented based on spaceborne observations. The need for a more realistic ice cloud optical model to obtain spectrally consistent retrievals is demonstrated. Furthermore, to complement ice cloud property studies based on passive radiometric measurements, the advantage of incorporating lidar and/or polarimetric measurements is discussed.The performance of ice cloud models based on the use of different ice habits to represent ice particles is illustrated by comparing model results with satellite observations. A summary is provided of a number of parameterization schemes for ice cloud radiative properties that were developed for application to broadband radiative transfer submodels within general circulation models（GCMs）. The availability of the single-scattering properties of complex ice habits has led to more accurate radiation parameterizations. In conclusion, the importance of using nonspherical ice particle models in GCM simulations for climate studies is proven.
文摘Linearization of Radiative Transfer Equation (RTE) is the key step in physical retrieval of atmospheric temperature and moisture profiles from InfRared (IR) sounder observations. In this paper, the successive forms of temperature and water vapor mixing ratio component weighting functions are derived by applying one term variation method to RTE with surface emissivity and solar reflectivity contained. Retrivals of temperature and water vapor mixing ratio profiles from simulated Atmospheric Infrared Sounder (AIRS) observations with surface emissivity and solar reflectivity are presented.
基金Support from the Office of Polar Programs, Geoscience Directorate, National Science Foundation via grants #PLR-1625904, #PLR-1543305, and #PLR-1535632the National Center for Atmospheric Researchits Mesoscale and Microscale Meteorology Laboratory for hosting the workshop and providing support for it
文摘1.Overview The 12th Workshop on Antarctic Meteorology and Climate（WAMC）,formerly known as the Antarctic Meteorological Observation,Modeling,and Forecasting（AMOMF）Workshop（AMOMFW）,was held at the National Center for Atmospheric Research（NCAR）in Boulder,Colorado,USA on 26–28 June 2017.The annual workshop dates from 2006,and recent meetings have been the 10th AMOMF Workshop held in 2015 in Cambridge,
基金supported by the Division of Polar Programs,Geoscience Directorate,National Science Foundation grant number ANT-1245663
文摘1. Overview The 10th Antarctic Meteorological Observation, Modeling, and Forecasting Workshop （hereinafter AMOMFW） took place June 17-19, 2015 in the historic city of Cambridge, United Kingdom. The meeting followed its purpose of connecting Antarctic atmospheric science to weatherrelated operational issues and advances in observing, modeling, forecasting, and understanding the Antarctic environment.
基金Financial Support from the Office of Polar Programs, National Science Foundation (Grant Nos. NSF 1924730, 1951720, and 1951603)
文摘1.Overview August 2022 marked the 17th Workshop on Antarctic Meteorology and Climate(WAMC)which was held in a hybrid format at the Pyle Center at the University of Wisconsin-Madison(UW-Madison)in Madison,WI,USA.The workshop is the first partial in-person gathering since the 14th WAMC(Lazzara et al.,2018)as the 15th WAMC was canceled due to the COVID-19 pandemic,and the 16th WAMC(Bromwich et al.,2022)was purely online.Global members of the Antarctic meteorological community gathered at this meeting to present and discuss weather-related topics encompassing scientific research and support operations within Antarctic meteorology and climate.These conversations aimed to share and discuss results,future developments,and build collaborative plans.
基金the University of Wisconsin-Madison for their comments and help.Support from the Office of Polar Programs,National Science Foundation(Grant Nos.PLR-1543305,PLR-1535632,and PLR-1625904),is greatly appreciated.
文摘1.Overview In July 2018,the Antarctic community came together to meet at the 13th Workshop on Antarctic Meteorology and Climate(WAMC)in Madison,Wisconsin,USA(Fig.1);and in the following year in June 2019,the 14th WAMC was held in Charleston,South Carolina,USA(Fig.2).With a growing history,the WAMC addresses the topics of Antarctic meteorology and climate(Kameda et al.,2008;Colwell et al.,2016;Lazzara et al.,2018)as well as weather-related issues of scientific and operational support.The workshops bring together researchers,operational forecasters,numerical modelers,observational specialists,and students.The themes of both workshops included Antarctic meteorological observations,Antarctic atmospheric numerical modeling,Antarctic meteorological and climate research,and Antarctic weather forecasting and operational services.The 2018 and 2019 WAMC were both followed by a one-day focus on the Year of Polar Prediction-Southern Hemisphere(YOPP-SH),when preparations and follow-up discussions were made with regard to the YOPP Special Observing Period from 16 November 2018 to 15 February 2019.
基金support from the US National Science Foundation(Grant Nos.1924730,2301362,and 2205398).
文摘Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely impacted.Specifically,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the aircraft.The cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low temperatures.Four separate cold phases were identified,each a few days in duration and occurring from mid-July to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold temperatures.The monthly 500-hPa geopotential height anomalies show strong negative anomalies in August.Examination of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric conditions.Understanding the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology.
基金the International Association of Meteorology and Atmospheric Science(IAMAS)/International Commission on Polar Meteorology(ICPM)Scientific Committee on Antarctic Research(SCAR)+2 种基金the World Meteorological Organization(WMO)for supporting these workshopsFinancial Support from the Office of Polar ProgramsNational Science Foundation(Grant No.NSF 1823135,1924730,192473,and 1951603)。
文摘1.Overview In June 2021,the 16th Workshop on Antarctic Meteorology and Climate(WAMC)and the 6th Year of Polar Prediction in the Southern Hemisphere(YOPP-SH)Meeting(http://polarmet.osu.edu/WAMC;021/)were held online and hosted by the Polar Meteorology Group at Byrd Polar and Climate Research Center,The Ohio State University,Columbus,Ohio(Fig.1).
文摘To estimate sea surface temperature(SST)with high accuracy from radiometrie measure- ments,it is no longer acceptable to assume that sea surface emissivity is unity or any other con- stant.This note presents an investigation of the desirable emissivity accuracy in relation to re- trieval.It was found that 1% error in surface emissivity can cause up to 0.7 K error in the re- trieved SST,although this sensitivity is often reduced to about 0.5 K on average because of the downward atmospheric radiation at surface partially compensates for the emissivity error.Since the downward atmospheric radiation ratio is controlled to a large extent by the integrated water vapor in the atmosphere and,secondarily,by view angle,the sensitivity of SST retrieval to surface emis- sivity has been computed as a function of these two parameters.
文摘Despite decades of theoretical research and observational studies, a good understanding of tropical cyclone genesis(TCG) remains elusive. One school of theories proposes that TCG within an African Easterly Wave results from “bottom-up” development of cyclonic vorticity that is contingent upon favorable conditions in the lower-troposphere and boundary layer. Our observational study suggests that while lower-tropospheric forcing is a necessary condition for this type of TCG, it may not be sufficient in some cases, and that environmental conditions in the upper levels can have an influence. Specifically, we find evidence to suggest that pre-TCG upper-tropospheric flow patterns characterized by core-connecting outflow vents to the environment can in certain situations provide a modulating effect on Atlantic tropical disturbances trying to develop. Patterns of nearenvironment upper-level inertial stability, divergence, outflow setup, and mass evacuation are identified and related to surface development. The study employs high-resolution satellite-derived wind data, aircraft GPS dropwindsondes, composite fields, multivariate objective analyses, and case studies to help identify conditions in the upper-level environment that can play a role in Atlantic TCG events.
