Premium
Gravity Wave Weakening During the 2019 Antarctic Stratospheric Sudden Warming
Author(s) -
Kogure Masaru,
Yue Jia,
Liu Huixin
Publication year - 2021
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2021gl092537
Subject(s) - climatology , geology , atmospheric sciences , sudden stratospheric warming , polar , polar vortex , stratosphere , gravity wave , environmental science , gravitational wave , physics , astronomy , astrophysics
A rare Antarctic stratospheric sudden warming (SSW) occurred on August 30, 2019, and was a minor warming event. We investigated variations in gravity wave (GW) activity before and after this Antarctic SSW event using two satellite measurements (AIRS and CIPS) and reanalysis data (GEOS‐5 FP). GW activity over the Andes decreased after August 30, although the westerly wind was 40–60 ms −1 and cannot filter out GWs with small zonal phase speed. This decline over the Andes was probably caused by wave saturation. Zonal mean GW activity over Antarctica and the Southern Ocean likewise decreased, with a weakening of zonal wind. The zonal mean GW activity further decreased around September 8 which coincided with a reversal of the zonal mean zonal wind at 40 km. The decline in the zonal mean GW activity after August 30 was probably caused by wind filtering and polar night jet breaking.