Field Measurements and Preliminary Simulation of Atmospheric Boundary Layer Evolution in EPIC2001

University Of Washington, Seattle WA

Investigators

Abstract

EPIC (Eastern Pacific Investigation of Climate processes in the coupled ocean-atmosphere system) is an activity of the US CLIVAR Program. EPIC 2001 consists of four components focussing on (i) intertropical convergence zone/warm pool phenomena; (ii) cross-equatorial inflow into the intertropical convergence zone; (iii) upper ocean structure and mixing and (iv) an exploratory study of boundary layer cloud properties in the southeasterly tradewind regime. The field phase of EPIC 2001 is scheduled for a 6-week period during the interval Sept 1 to Oct 15, 2001. In addition to the eight awards made by ATM, this collaborative research has awards made by NSF/OCE and NOAA/OGP. During the field phase, the PI will add special sensors to an existing buoy array to collect atmospheric pressure data at a temporal resolution of 10 minutes. He also will conduct preliminary large-eddy simulations of the quasi-lagrangian evolution of the planetary boundary layer as it is advected across the equatorial cold tongue and into the ITCZ. A combination of in-situ soundings from past studies and September climatology from the NCEP reanalysis will be used to initialize and force these simulations. The work is important because it will improve understanding and modeling of climate variability over the eastern tropical Pacific.