An Investigation of Intensity, Structural, and Timing Extremes for Extratropical Transition
Mentor 1
Clark Evans
Location
Union Wisconsin Room
Start Date
5-4-2019 1:30 PM
End Date
5-4-2019 3:30 PM
Description
Giorgio Sarro Clark Evans
An Investigation of Intensity, Structural, and Timing Extremes for Extratropical Transition
Extratropical transition (ET) is a poorly studied subject with large impacts on several developed countries. As defined in previous research, ET is the process by which a tropical cyclone transforms into a non-tropical, or extratropical, cyclone after it encounters frontal systems and reduced sea-surface temperature at higher latitudes. A notable example of the direct impacts of ET is Hurricane Sandy. Sandy underwent ET just before hitting the eastern United States with a major storm surge and expansive wind field.
In this study, we focus on improving understanding of the atmospheric conditions associated with different ET outcomes. Previous studies examined only a limited number of storms, yet the results are cited extensively. The primary goal of this research is to increase the number of analyzed storms. In doing so, it will confirm or deny the conclusions of previous studies and will develop new understanding.
In this research, we focus on the Atlantic basin and analyze all the storms that undergo ET since 1995. Storms are divided into three categories: storms that became stronger, weaker, or did not change intensity after ET, based on the maximum surface wind speed. Because land significantly impacts storm strength, we remove cases that made landfall in the three days prior to ET completing. Next, all cyclone tracks, as well as atmospheric fields from the ERA5 Reanalysis, are obtained, and a phase-based diagram is used to more precisely document ET timing.
Future work will consist of deeper analysis to note atmospheric patterns associated with distinctions during and after ET: post-ET intensity, ET duration, and does the storm have a purely non-tropical or a hybrid tropical/non-tropical structure post-ET.
An Investigation of Intensity, Structural, and Timing Extremes for Extratropical Transition
Union Wisconsin Room
Giorgio Sarro Clark Evans
An Investigation of Intensity, Structural, and Timing Extremes for Extratropical Transition
Extratropical transition (ET) is a poorly studied subject with large impacts on several developed countries. As defined in previous research, ET is the process by which a tropical cyclone transforms into a non-tropical, or extratropical, cyclone after it encounters frontal systems and reduced sea-surface temperature at higher latitudes. A notable example of the direct impacts of ET is Hurricane Sandy. Sandy underwent ET just before hitting the eastern United States with a major storm surge and expansive wind field.
In this study, we focus on improving understanding of the atmospheric conditions associated with different ET outcomes. Previous studies examined only a limited number of storms, yet the results are cited extensively. The primary goal of this research is to increase the number of analyzed storms. In doing so, it will confirm or deny the conclusions of previous studies and will develop new understanding.
In this research, we focus on the Atlantic basin and analyze all the storms that undergo ET since 1995. Storms are divided into three categories: storms that became stronger, weaker, or did not change intensity after ET, based on the maximum surface wind speed. Because land significantly impacts storm strength, we remove cases that made landfall in the three days prior to ET completing. Next, all cyclone tracks, as well as atmospheric fields from the ERA5 Reanalysis, are obtained, and a phase-based diagram is used to more precisely document ET timing.
Future work will consist of deeper analysis to note atmospheric patterns associated with distinctions during and after ET: post-ET intensity, ET duration, and does the storm have a purely non-tropical or a hybrid tropical/non-tropical structure post-ET.
