Detection of Sudden Stratospheric Warming Events

Sudden stratospheric warming (SSW) events are events that split or displace the stratospheric polar vortex.  There are two types of SSW events: major events, which consist of a latitudinal mean temperature increase (greater than 25 K in less than a week) poleward from 60° N and an associated circulation reversal, and minor events, which only consist of a latitudinal mean temperature increase.  The work presented here includes an analysis of a major SSW event that occurred in January 2013.  Differences in the detection and observed evolution of this event from the Cross-track Infrared Sensor (CrIS), which is located on the Suomi National Polar-orbiting Partnership (S-NPP) satellite, and multiple reanalysis datasets (Merra-2, ERA-Interim, and JRA-55) that have different temporal and spatial resolutions are compared.  Findings will show how instrumentation on current satellites can serve as real time detectors of SSW events in order to learn more about these events.  This new information can help improve tropospheric forecasts as SSW events can often precede extreme weather regimes in the troposphere.