First Detection of a Brief Mesoscale Elevated Stratopause in Very Early Winter

Abstract Elevated stratopauses are typically associated with prolonged disturbed conditions in the Northern Hemisphere polar winter. The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and the Microwave Limb Sounder (MLS) observed a short‐lived and highly zonally asymmetric stratop...

Full description

Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Maya García‐Comas, Bernd Funke, Manuel López‐Puertas, Francisco González‐Galindo, Michael Kiefer, Michael Höpfner
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2020
Subjects:
Online Access:https://doi.org/10.1029/2019GL086751
https://doaj.org/article/908ac74df9aa43dd9b9652302be4186c
Description
Summary:Abstract Elevated stratopauses are typically associated with prolonged disturbed conditions in the Northern Hemisphere polar winter. The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and the Microwave Limb Sounder (MLS) observed a short‐lived and highly zonally asymmetric stratopause at mesospheric altitudes in November 2009, the earliest in the season reported so far. The Arctic climatological winter stratopause vanished, and MIPAS and MLS measured temperatures of 260 K at 82 km and 250 K at 75 km, respectively, in a region smaller than in typical midwinter elevated stratopause events. Planetary wave activity was initially high. Zonal mean zonal winds and the poleward temperature gradient northward of 70°N stayed reversed during 7 days, but the mesosphere did not cool. Wave activity dropped until the eastward stratospheric winds resumed and a strong vortex restored in the mesosphere. The stratopause emerged at high altitudes, staying there for 2–5 days. It was accompanied by enhanced downward transport. It took the stratopause 9 days to move down to its typical winter altitudes.