The S = 3 Eastward-Propagating Diurnal Tide in the Mesosphere and Thermosphere due to Heating Rates from the NCEP/NCAR Reanalysis Project
Abstract
The NCEP/NCAR Reanalysis Project offers the opportunity to examine the mesospheric and thermospheric consequences of tropospheric heating rates derived from a comprehensive model utilizing assimilated data. In this paper the Global Scale Wave Model (GSWM), a climatological model of zonal mean winds, and the NCEP/NCAR heating rates are used to better understand the origins and behavior of the eastward- propagating diurnal tide with zonal wavenumber s = 3 (DE3). This oscillation is a prominent feature of the modeled wind and temperature fields above 80 km at equatorial and tropical latitudes. We illustrate how the seasonal cycles of eastward and northward wind components of DE3 reflect the combined influences of zonal mean zonal winds, tropospheric forcing and dissipation. In addition, the relative importance of forcing by shortwave radiation absorption and convective and condensation heating are illustrated. The global effects of DE3 and consistency with observational data, possibly including those from the TIMED Mission, are also discussed.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2002
- Bibcode:
- 2002AGUSMSA21A..08T
- Keywords:
-
- 0340 Middle atmosphere: composition and chemistry;
- 0350 Pressure;
- density;
- and temperature;
- 0355 Thermosphere: composition and chemistry : : : : : : : : : : : : : : :;
- 3332 Mesospheric dynamics;
- 3367 Theoretical modeling;
- 3369 Thermospheric dynamics (0358);
- 3384 Waves and tides