Analisis kondisi dinamika atmosfer berdasarkan citra satelit, model reanalisis dan data observasi (studi kasus hujan es di Depok pada 10 Januari 2023)

Abstrak

Hail is an extreme weather phenomenon from convective systems such as cumulonimbus (Cb) clouds that rarely occurs but has a significant impact on infrastructure, agriculture, and safety. This study analyzes the atmospheric dynamics affecting hail in Depok on January 10, 2023, at 08:40 UTC using Himawari-9 satellite data, the ERA-5 model, and upper-air soundings. Himawari-9 data were analyzed using the SATAID software through IR channel interpretation and the RGB Day Convective Storms and 24-hour Microphysics methods. ERA-5 data produces timeseries graphs of atmospheric variables, while sounding data is visualized with Skew-T log-P diagrams and atmospheric instability indices. Analysis shows the life cycle of cumulonimbus clouds with peak temperatures below -60°C. Divergence parameters indicate significant convergence in the lower layer, divergence in the upper layer, and high humidity in the middle and upper layers, which support the formation of ice crystals. Atmospheric instability indices such as TT, KI, SWEAT, CAPE, LI, and Showalter Index indicate atmospheric instability and convective energy.