Simulation of Convective Cloud Rainfall in Jakarta-Indonesia

Simulation of Convective Cloud Rainfall in Jakarta Using Regional Weather Model





Rahmat Gernowo
Faculty of Mathematics and Natural Sciences, Diponegoro University, Semarang Indonesia#1
Prof. Sudarto Street, Tembalang Semarang.Indonesia
Email: gernowo1@yahoo.com

Bayong Tj. H.K
Atmosphere Science Research Group, Bandung Institute of Technology
Ganesha No. 10 Street, Bandung 40132,Indonesia

The Houw Liong
Physics of Complex System Research Grooup, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology
Ganesha No. 10 Street, Bandung 40132, Indonesia

Tri Wahyu Hadi
Atmosphere Science Research Group, Bandung Institute of Technology
Ganesha No. 10 Street, Bandung 40132,Indonesia


ABSTRACT
The dynamics of rain cloud especially in area of Jakarta represent an important matter in seeking solution, and to prevent floods especially in Jakarta. The research of convection pattern above area of DKI-Jakarta based on meteorological data from high resolution satellite image which is expected to increase the understanding of growth of convection cloud that caused torrential rains and floods in DKI-Jakarta on 2002 and 2007. The special analysis of characteristics of the convective rainfall that initiated the Jakarta Flood event of January/February2002 and 2007 have been done using WRF (weather research and forecasting), a regional numerical weather model developed by Pennsylvania State University/ National Center for Atmospheric Research (PSU/NCAR), with a horizontal grid resolution of 5 km. The global troposphere analysis data from National Center for Environmental Prediction (NCEP) was used as input for the initial and boundary condition. Cloud-top temperature data derived from satellite imageries were utilized to identify the convective clouds. It is found that the temporal and spatial distribution of the simulated convective rainfall during 28 - 31 January 2002 and 31 January - 2 February 2007 are in qualitative agreement with satellite observations of cloud-top temperature variations.
This study contributes to understand extreme rainfalls in DKI-Jakarta. The cloud dynamics in DKI-Jakarta caused by local atmospheric circulation factor and analysis of the model output also revealed that the convective clouds were generated by combined effect of cold-pool advection, mixing layer development, and topography.