Start
January 30, 2019 - 3:00 pm
End
January 30, 2019 - 4:00 pm
Address
120 David L Boren Blvd, Norman, OK 73072 View mapCategories
Weather and Climate SystemsWeather and Climate Seminar
Characterization of the Structure of Tropopause Polar Vortices using Remote Sensing
Ryan Pajela
Wednesday, January 30th
3:00pm/NWC 5930
Tropopause polar vortices (TPVs) are atmospheric coherent vortex-like structures originating poleward of the jet stream and exhibit a closed circulation of the wind along the 2-PVU dynamic tropopause. Cyclonic TPVs interact with the jet stream and synoptic mid-latitude systems and play an important role in the genesis and strengthening of surface cyclones as well as the variability of sea ice. This has been the motivation for previous and current studies in TPV behavior, evolution, climatology, and structure through the utilization of reanalysis and modeling components. However, observationally-based studies of TPVs are still relatively new, yet offer appreciable insight to TPV model-based research. As part of this endeavor, this project uses remote sensing techniques to observe the spatial variability within cyclonic TPVs and to verify these results with previous model studies on TPV spatial variability.
This study utilizes data from polar-orbiting satellite infrared and microwave retrievals, satellite-derived atmospheric motion vectors, and reanalysis datasets. Geographic information system (GIS) technology and a TPV tracking algorithm was used to collect cases of TPV events detected by satellite passes during 2012. Results from case studies support the TPV structure found in previous model studies, including a lowering of the tropopause, an upper-level cyclonic wind structure, relatively cooler (warmer) temperatures below (above) the tropopause than the surrounding environment, and higher (lower) relative humidity below (above) the tropopause. Individual cases also demonstrated highly variable moisture fields below the tropopause. As part of a larger effort in TPV research, this project will complement numerical modeling and field components in the future.