Arctic polar vortex dynamics according to the delineation method using geopotential
V.V. Zuev, E.S. Savelieva, E.A. Sidorovski
Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: stratospheric polar vortice, delineation method, geopotential
Abstract
We compare the main characteristics of the Arctic polar vortex obtained from the NASA GSFC data (zonal mean wind at 60° N, mean temperature in the region 60-90° N) and by the vortex delineation method using geopotential (mean wind speed along the vortex edge, mean temperature inside the vortex) on the example of three largest Arctic ozone depletion events and on average over 1979-2021. The mean wind speed along the vortex edge according to the delineation method is on average two times higher than the zonal mean wind at 60° N and is 37.3 ± 5.6 and 58.9 ± 13.1 m/s in January at the 50 and 10 hPa levels, respectively. The mean temperature inside the vortex according to the delineation method is on average 5 °C lower than the mean temperature in the region 60-90° N in the lower stratosphere. The quantitative characteristics obtained expand the understanding of the Arctic polar vortex dynamics in the lower stratosphere.
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