Climatology of the diurnal tides from eCMAM30 (1979 to 2010) and its comparison with SABER

摘要: The extended Canadian Middle Atmosphere Model (eCMAM) was recently run in a nudged mode using reanalysis data from the ground to 1 hPa for period of January 1979 June 2010 (hence name eCMAM30). In this paper, eCMAM30 temperature is used examine background mean temperature, spectrum diurnal tides, and climatology migrating tide Dw1 three nonmigrating tides De3, Dw2, Ds0 stratosphere, mesosphere, lower thermosphere. model results are then compared tidal derived Sounding Broadband Emission Radiometry (SABER) observations between 40 110 km 50° S N 2002 December 2013. reproduces latitudinal gradients well except that cold mesopause 10 20 K colder than SABER. spectra their relative strengths compare very altitude-latitude structures four components (Dw1, Ds0) two datasets also good agreement even stratosphere with weaker amplitude. largest discrepancy SABER associated seasonal variation De3. addition Northern Hemisphere (NH) summer maximum, secondary maximum occurs during NH winter (December-February) but absent variations other agreement. Interannual time series De3 both reveal variability 25 26 months, which indicates modulation by stratospheric quasi-biennial oscillation (QBO).