[A-AS01] Large-scale moisture and organized cloud systems

[AAS01-09] Intraseasonal and Interannual Variability of Cumulonimbus Cloud over the Maritime Continent

*Suaydhi Suaydhi¹, Gammamerdianti -¹ (1.Indonesian National Institute of Aeronautics and Space)

Keywords:Cb cloud, Indonesia, ENSO, MJO

The distribution of cumulonimbus clouds over the Maritime Continent is analysed over different atmospheric conditions to investigate the influence of El Niño, La Niña, and MJO. The data used here are infrared brightness from the Himawari family satellites from 2000 to 2016, rainfall data from GSMaP, and ERA Interim reanalysis data. In this paper, the cloud types are identified using the 2-D threshold-based cloud type classification method with a threshold of cloud-top minimum value of 180 K. The results show that Cumulonimbus (Cb) and Mature Cumulonimbus (MCb) are more affected by El Niño, La Niña, and MJO phenomena, than other cloud types. When the MJO is active, Cb and MCb clouds are mostly concentrated in the vicinity of Sumatra, especially during El Niño. Clear sky is observed over the middle part of Indonesia during El Niño combined with active MJO. Cb and MCb clouds are more evenly distributed around Indonesia when there is MJO during normal or La Niña conditions. The distribution of the cloud changes during MJO event because it modifies and/or strengthens the low-level convergence in the atmosphere.