Global distribution of C T 2 at altitudes 30–50 km from space-borne observations of stellar scintillation

• Published in: Geophysical Research Letters
• Main Authors: S. Gurvich, Alexandre, Sofieva, Viktoria F., Dalaudier, Francis
• Other Authors: A.M.Obukhov Institute of Atmospheric Physics (IAP), Russian Academy of Sciences Moscow (RAS), Finnish Meteorological Institute (FMI), 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)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: turbulence; stellar scintillation; GOMOS/Envisat; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; polar night
• Online Access: https://hal.science/hal-00201348; https://hal.science/hal-00201348/document; https://hal.science/hal-00201348/file/Gurvich_et_al-2007-Geophysical_Research_Letters.pdf; https://doi.org/10.1029/2007GL031134

Locally isotropic turbulence in the stratosphere consists of isolated sporadic patches with random values of temperature structure characteristic C T 2 . Stellar scintillations measured aboard GOMOS/ENVISAT through the Earth atmosphere provided the first global distribution of the effective characteristic C 2 averaged along sounding ray. For zonal mean, the largest values are achieved in winter polar regions. This observed intense turbulence is probably related to the polar night jet. Relatively weak turbulence is observed at low latitudes. Turbulence intensity map is shown for altitude 42 km in the latitude band ±35°, where the maxima follow the sub-solar latitude, with enhancements located mainly over continents. Turbulence enhancements are not related with orography. Despite a noticeable correlation with typical regions of deep convection, the overall distribution of C T,eft 2 displays a more complicated structure. Analyzed data suggest that the main turbulence sources, at altitudes 〜40 km, are instabilities of stratospheric circulation and gravity wave breaking.