Wednesday, 12 February 2003: 4:00 PM
A case study of the Intertropical Convergence Zone at the ocean surface with high resolution satellite data
An in-depth study of the Intertropical Convergence Zone (ITCZ) over the eastern Pacific and Atlantic is performed for the summer of 2002. While the ITCZ is a well-known narrow zone of convergence, precipitation, and relatively warm waters, the positioning and interaction of these components is an area of active research. Climatological studies of the ITCZ have relied on monthly observations from ships and satellites at coarse (~2°latidude/longitude) resolution. Field experiments have added important details to these climatologies, but are necessarily limited in time and space. 2002 marks the first year of a high resolution Tropical Rainfall Measuring Mission (TRMM) global precipitation product (3B42RT). All available microwave- and infrared-based precipitation estimates are combined at 0.25° resolution every 3-hours in near-real-time. 3B42RT adds to an already consistent set of air-sea observations from space (SST from TRMM and winds from Quickscat). The satellite estimates will be combined to answer key questions related to the intraseasonal variability of the ITCZ. For example: what are the feedbacks between convection, circulation, and placement of the ITCZ? What is the nature of the Intertropical Divergence Zone? What are the air-sea mechanisms that bring about the mid-summer drought over Central America? This study is further intended as a test case for a "field campaign from space" to take place during the North American Monsoon Experiment in 2004.