A Modern 3-Years Climatology of North Atlantic and Western North Pacific Extratropical Cyclones

• Main Author: Kaminski, Anna
• Format: Text
• Language: unknown
• Published: UWM Digital Commons 2021
• Subjects: Pacific; North Atlantic
• Online Access: https://dc.uwm.edu/uwsurca/2021/sera/5

Extratropical transition (ET) is a frequently studied process that occurs when a tropical cyclone starts to transition into an extratropical cyclone. During this process, the cyclone starts to interact with a baroclinic zone and cooler sea-surface temperatures at higher latitudes which ultimately leads to the transition into the extratropical cyclone. Previous climatologies have shown that there are numerous ways to analyze this transformation. For example, the Cyclone Phase Space (CPS) has been one objective way to examine ET, however, there have been some drawbacks. The CPS focuses on symmetry of the cyclone as well as if the core of the cyclone is warm or cold. While this method seems to be quite direct, specific cases of ET have shown that some cases are not fully reliable through this method. In addition to the CPS, satellite images have been used to also help determine ET, specifically looking at the symmetry and cloud patterns of the cyclone, however, this method is considered more subjective and varies based on who is analyzing the data. The overarching goal of this study is to create an algorithm to objectively identify ET by analyzing large numbers of satellite images and characterize the different transformations cyclones go through. However, to do so requires large input databases of both tropical and extratropical cyclone satellite images, which themselves necessitate generating tropical and extratropical cyclone climatologies. This presentation will describe the generation of the extratropical cyclone climatology, focusing on the North Atlantic and western North Pacific basins from 2017-19 (i.e., the GOES-16 and Himawari-8 next-generation geostationary satellite imager era).Through this process, we are expecting to create an additional resource for individuals studying ET and develop a potentially more objective method to evaluate ET.