The role of the QBO in the inter-hemispheric coupling of summer mesospheric temperatures
Artikel i vetenskaplig tidskrift, 2011

Inter-hemispheric coupling between the polar summer mesosphere and planetary-wave activity in the extra-tropical winter stratosphere has recently been inferred using Polar Mesospheric Cloud (PMC) properties as a proxy for mesospheric temperature (Karlsson et al., 2007). Here we confirm these results using a ten-year time series of July mesospheric temperatures near 60 degrees N derived from the hydroxyl (OH) nightglow. In addition, we show that the time-lagged correlation between these summer mesospheric temperatures and the ECMWF winter stratospheric temperatures displays a strong Quasi-Biennial Oscillation (QBO). The sign and phase of the correlation is consistent with the QBO modulation of the extra-tropical stratospheric dynamics in the Southern Hemisphere via the Holton-Tan mechanism (Holton and Tan, 1980). This lends strength to the identification of synoptic and planetary waves as the driver of the inter-hemispheric coupling, and results in a strong QBO modulation of the polar summer mesospheric temperatures.

quasi-biennial oscillation

thermal

hydroxyl airglow

solar-activity

semidiurnal tide

mesopause circulation

structure

general-circulation

middle atmosphere

lower thermosphere

large-scale

Författare

P. J. Espy

Norges teknisk-naturvitenskapelige universitet

S. O. Fernandez

Norges teknisk-naturvitenskapelige universitet

Universidad de Cantabria

Peter Forkman

Chalmers, Rymd- och geovetenskap, Global miljömätteknik och modellering

Donal Murtagh

Chalmers, Rymd- och geovetenskap, Global miljömätteknik och modellering

J. Stegman

Stockholms universitet

Atmospheric Chemistry and Physics

1680-7316 (ISSN) 1680-7324 (eISSN)

Vol. 11 495-502

Ämneskategorier

Meteorologi och atmosfärforskning

DOI

10.5194/acp-11-495-2011