Impact of ENSO on seasonal variations of Kelvin Waves and mixed Rossby-Gravity Waves

3rd International Symposium on LAPAN-IPB Satellite For Food Security and Environmental Monitoring 2016

地球科学;轻工业;生态环境科学

Rakhman, Saeful^1 ; Lubis, Sandro W.^2 ; Setiawan, Sonni^1

Department of Geophysics and Meteorology, Bogor Agricultural University (IPB), Indonesia^1

Physics of the Atmoshpere, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany^2

关键词: Atmospheric convection;    Local variations;    Rossby-gravity wave;    Sea surface temperature (SST);    Seasonal variation;    Southern oscillation;    Tropical convective activity;    Tropical Pacific ocean;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/54/1/012035/pdf
DOI  :  10.1088/1755-1315/54/1/012035

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Characteristics of atmospheric equatorial Kelvin waves and mixed Rossby-Gravity (MRG) waves as well as their relationship with tropical convective activity associated with El Niño-Southern Oscillation (ENSO) were analyzed. Kelvin waves and MRG waves were identified by using a Space-Time Spectral Analysis (STSA) technique, where the differences in the strength of both waves were quantified by taking the wave spectrum differences for each ENSO phase. Our result showed that Kelvin wave activity is stronger during an El Nino years, whereas the MRG wave activity is stronger during the La Nina years. Seasonal variations of Kelvin wave activity occurs predominantly in MAM over the central to the east Pacific in the El Nino years, while the strongest seasonal variation of MRG wave activity occus in MAM and SON over the northern and southern Pacific during La Nina years. The local variation of Kelvin wave and MRG wave activities are found to be controlled by variation in lower level atmospheric convection induced by sea surface temperature in the tropical Pacific Ocean.