The evolution of the stratopause during the 2006 major warming: Satellite data and assimilated meteorological analyses

	Become an AGU Member Subscribe to AGU Journals



Read Full Article (file size: 17914892 bytes) Cited by JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, D11115, doi:10.1029/2007JD009097, 2008 The evolution of the stratopause during the 2006 major warming: Satellite data and assimilated meteorological analyses Gloria L. Manney Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA Department of Physics, New Mexico Institute of Mining and Technology, Socorro, New Mexico, USA Kirstin Krüger Leibniz-Institute for Marine Sciences, Kiel University (IFM-GEOMAR), Kiel, Germany Steven Pawson Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA Ken Minschwaner Department of Physics, New Mexico Institute of Mining and Technology, Socorro, New Mexico, USA Michael J. Schwartz Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA William H. Daffer Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA Nathaniel J. Livesey Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA Martin G. Mlynczak Science Directorate, NASA Langley Research Center, Hampton, Virginia, USA Ellis E. Remsberg Science Directorate, NASA Langley Research Center, Hampton, Virginia, USA James M. Russell III Department of Physics, Hampton University, Hampton, Virginia, USA Joe W. Waters Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA Abstract Microwave Limb Sounder and Sounding of the Atmosphere with Broadband Emission Radiometry data provide the first opportunity to characterize the four-dimensional stratopause evolution throughout the life-cycle of a major stratospheric sudden warming (SSW). The polar stratopause, usually higher than that at midlatitudes, dropped by ∼30 km and warmed during development of a major “wave 1” SSW in January 2006, with accompanying mesospheric cooling. When the polar vortex broke down, the stratopause cooled and became ill-defined, with a nearly isothermal stratosphere. After the polar vortex started to recover in the upper stratosphere/lower mesosphere (USLM), a cool stratopause reformed above 75 km, then dropped and warmed; both the mesosphere above and the stratosphere below cooled at this time. The polar stratopause remained separated from that at midlatitudes across the core of the polar night jet. In the early stages of the SSW, the strongly tilted (westward with increasing altitude) polar vortex extended into the mesosphere, and enclosed a secondary temperature maximum extending westward and slightly equatorward from the highest altitude part of the polar stratopause over the cool stratopause near the vortex edge. The temperature evolution in the USLM resulted in strongly enhanced radiative cooling in the mesosphere during the recovery from the SSW, but significantly reduced radiative cooling in the upper stratosphere. Assimilated meteorological analyses from the European Centre for Medium-Range weather Forecasts (ECMWF) and Goddard Earth Observing System Version 5.0.1 (GEOS-5), which are not constrained by data at polar stratopause altitudes and have model tops near 80 km, could not capture the secondary temperature maximum or the high stratopause after the SSW; they also misrepresent polar temperature structure during and after the stratopause breakdown, leading to large biases in their radiative heating rates. ECMWF analyses represent the stratospheric temperature structure more accurately, suggesting a better representation of vertical motion; GEOS-5 analyses more faithfully describe stratopause level wind and wave amplitudes. The high-quality satellite temperature data used here provide the first daily, global, multiannual data sets suitable for assessing and, eventually, improving representation of the USLM in models and assimilation systems. Received 25 June 2007; accepted 15 February 2008; published 12 June 2008. Index Terms: 3334 Atmospheric Processes: Middle atmosphere dynamics (0341, 0342); 0341 Atmospheric Composition and Structure: Middle atmosphere: constituent transport and chemistry (3334); 3315 Atmospheric Processes: Data assimilation; 1616 Global Change: Climate variability (1635, 3305, 3309, 4215, 4513). Read Full Article (file size: 17914892 bytes) Cited by Citation: Manney, G. L., et al. (2008), The evolution of the stratopause during the 2006 major warming: Satellite data and assimilated meteorological analyses, J. Geophys. Res., 113, D11115, doi:10.1029/2007JD009097. Copyright 2008 by the American Geophysical Union.

Abstract