Activity of convective coupled equatorial wave in tropical Tropopause layer in reanalysis and high-top CMIP5 models

[摘要] The activity of convectively coupled equatorial waves (CCEWs), including Kelvin waves, Mixed Rossby-Gravity (MRG), and Equatorial Rossby (ER), in the tropical tropopause layer (TTL) is investigated in the Reanalysis and nine high-top CMIP5 models using the zonal wave number-frequency spectral analysis with equatorially symmetric-antisymmetric decomposition. We found that the TTL activities in the high-top CMIP5 models show significant difference among the high-top CMIP5 models with respect to the observation. The MIROC and HadGEM2-CC models work best in simulating Kelvin wave in the TTL, while the HadGEM2-CC and MPI-ESM-LR models work best in simulating MRG waves. The ER waves in TTL are best simulated in the MRI-CGCM model. None of the models are good in simulating all waves at once. It is concluded that the broad range of wave activity found in the different CMIP5 models depend on the convective parameterization used by each model and the representation of the tropical stratosphere variability, including the QBO.

[发布机构] Department of Geophysics and Meteorology, Bogor Agricultural University (IPB), Indonesia^1;Department of the Geophysical Sciences, University of Chicago, Chicago, United States^2

[效力级别] 生态环境科学

[关键词] Anti-symmetric;Convective parameterization;Equatorial waves;Kelvin waves;Tropical stratosphere;Tropical tropopause layers;Wave activity;Wave numbers