Global analysis of scintillation variance: Indication of gravity wave breaking in the polar winter upper stratosphere

• Published in: Geophysical Research Letters
• Main Authors: Sofieva, Viktoria F., Kyrölä, Erkki, Hassinen, Seppo, Backman, Leif, Tamminen, Johanna, Seppälä, Annika, Thölix, Laura, Gurvich, Alexandre S., Kan, Valery, Dalaudier, Francis, Hauchecorne, Alain, Bertaux, Jean-Loup, Fussen, Didier, Vanhellemont, Filip, Fanton d' Andon, Odile, Barrot, Gilbert, Mangin, Antoine, Guirlet, Marielle, Fehr, Thorsten, Snoeij, Paul, Saavedra, Lidia, Koopman, Rob, Fraisse, Renaud
• Other Authors: Finnish Meteorological Institute (FMI), A.M.Obukhov Institute of Atmospheric Physics (IAP), Russian Academy of Sciences Moscow (RAS), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Analytic and Computational Research, Inc. - Earth Sciences (ACRI-ST), European Space Research Institute (ESRIN), Agence Spatiale Européenne = European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Astrium Toulouse, EADS - European Aeronautic Defense and Space
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; polar night
• Online Access: https://hal.science/hal-00162013; https://hal.science/hal-00162013/document; https://hal.science/hal-00162013/file/Sofieva.pdf; https://doi.org/10.1029/2006GL028132

Stellar scintillations observed through the Earth atmosphere are caused by air density irregularities generated mainly by internal gravity waves and turbulence. We present global analysis of scintillation variance in two seasons of year 2003 based on GOMOS/Envisat fast photometer measurements. Scintillation variance can serve as a qualitative indicator of intensity of small-scale processes in the stratosphere. Strong increase of scintillation variance at high latitudes in winter is observed. The maximum of scintillation variance can be associated with the polar night jet. The simplified spectral analysis has shown the transition of scintillation spectra toward small scales with altitude, which is probably related with turbulence appearing as a result of wave breaking. The breaking of gravity waves in the polar night jet seems to start in the upper stratosphere, a predicted, but not confirmed by observations before, feature. Weaker enhancements in tropics are also observed; they might be related to tropical convection.