Soundings, C-band Radar, Data Synthesis and Model Intercomparison for the EPIC2001 Stratocumulus Study

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 PIs will collect data from GPS soundings and from scanning C-band radar permanently mounted aboard R/V Ron Brown. The boundary layer and cloud structure documented by these and other observations taken on the cruise will be compared with that from reanalyses and selected general circulation models. A goal of the integrative data analysis is to assess whether precipitation processes are significantly influencing cloud thickness and albedo over large spatial scales, and if so, under what environmental conditions. The work is important because it will improve understanding and modeling of climate variability over the eastern tropical Pacific.