Variability and predictability of the intertropical Convergence Zone Over Indonesia

The Intertropical Convergence Zone (ITCZ) is a zone of low-pressure near the equator where two easterly winds originating from the Northern and Southern hemispheres converge Characterized by enhanced convection, cloudiness, and rainfall this zone constitutes the rising branch of the meridional Hadley circulation. The non-uniform distribution of the lands and seas introduces zonal asymmetries in heating which drive an east-west overturning, known as the Walker circulation, wherein air rises at longitudes of heating and sinks at the other longitudes. The three-quasi permanent centers of the rising branch of the Walker circulation are located over Indonesia, central Africa, and the Amazon basin. The structure, position, and migration of the ITCZ are important in defining and analyzing not only the tropical climate, but also the global climate. In this study, we firstly examine the variability of the ITCZ over the tropics. Secondly, we evaluate model performances of long-term and short-term ITCZ predictions over Indonesia based on statistical approaches and numerical simulations, respectively.