A composite analysis of the Mesoscale Convective Complexes (MCCs) development over the Central Kalimantan and its relation with the propagation of the rainfall systems

Abstract

The composite analysis for 45-cases of the MCC which identified by using infrared satellite imagery over the Central Kalimantan (110° - 116°E, 4°S - 1°N) has been observed. The data used is a combination of satellite data and reanalysis data. This study reported that the MCCs develops triggered by the orographic convective that helped by the convergent surface wind flow through interaction with the sea breeze in the afternoon until midnight and dissipated in the morning. The new convective systems are generated by the divergent outflow of the cold pool, in conjunction with the morning land breeze during MCCs mature. After dissipated, the new convective systems induce the land convection over the Java Island that became heavy rainfall. The initial and mature region are characterized by weak low-level convergence and upper-level divergence, but the low-level divergence begin appear during mature. The MCC develops largely driven by MCC-scale moisture convergence in the lower troposphere and cold core structure in the lower level. The weak surface divergence and upper-level divergence, warm advection in the lower atmosphere are dissipation characteristics. MCCs develop due to low-level cold advection and temperature and separated when dissipated that indicate the existence of the new convective systems propagation.