VERIFYING THE REPRESENTATION OF TROPICAL EASTERLY WAVES IN COMMUNITY CLIMATE MODEL VERSION 4

A descriptive evaluation of the Community Climate Model version 4 (CCSM4) was performed to assess its ability to realistically simulate African easterly wave (AEW) activity. Of particular interest, does a hindcast run of CCSM4 produce AEW at approximately the same frequency as documented in the Climate Forecasting System Reanalysis (CFSR) data set during the period 1979–2005? To address this, the meridional wind anomaly at 700 hPa was evaluated using an algorithm that employed a pattern of overlapping meridional means in an area bounded by 7°N to 15°N and 20°W to 25°W. This algorithm was designed to detect a meridional wind shift of 5 knots northerly to 5 knots southerly over a period of two days. The results indicate that CCSM4 simulates AEW at realistic frequencies as compared to CFSR. This method could be applied to the other variations of Climate Model Intercomparison Project 5 (CMIP5) to detect and evaluate AEW activity.http://archive.org/details/verifyingtherepr1094564132Lieutenant, United States NavyApproved for public release; distribution is unlimited