Seasonal variation in the vertical profile of the raindrop size distribution for stratiform rain as inferred from micro rain radar observations at Kototabang

The seasonal variation in the vertical structure of the Raindrop Size Distribution (RSD) from 0.45 km to 4.65 km above ground level during stratiform rain at Kototabang West Sumatra (0.20o S; 100.32o E; 865 m above sea level) has been investigated using Micro Rain Radar (MRR) observations during January 2012 – August 2016. Modified gamma distribution was using to parameterized the RSD and the parameter was calculated by a moment method. The data were classified into four seasons, i.e, Northeast/NE (December-March), Pre-southwest/pre-SW (April - May), SW (June - September), and pre-NE (October - November). The variation is strongly observed in very light to moderate intensity of stratiform rain. In these intensities Dm on ground for pre-monsoon has larger number than NE and SW seasons and have lower number of NT. It indicates that evaporation is most dominant on monsoon season and collision-coalescence is most dominant for pre-monsoon season.