EVALUATION OF MODEL BACK TRAJECTORIES OF THE KUWAIT OIL FIRES SMOKE PLUME USING DIGITAL SATELLITE DATA

This study evaluates the accuracy of the National Weather Service Medi um Range Forecast (MRF) global model outputs in simulating the transpo rt and dispersion of the Kuwait oil fire smoke plume. A technique was developed to analyze NOAA polar orbiting satellite imagery to obtain h orizontal smoke plume positions. The plume heights were obtained by co mbining the satellite analysis with back trajectory results. Backward trajectories were computed using both coarse and fine resolution MRF w ind fields. The average of the absolute value of relative trajectory e rror (\R.T.E.\) for the late summer period (24 July-15 September 1991) was about 10% of the travel distance when using the fine grid traject ories with the optimum plume centroid height and 14% when using the co arse grid model output. The absolute R.T.E. for the optimum plume heig ht runs was half of the R.T.E. for the constant starting height run (\ R.T.E.\ = 0.21). This difference indicates the importance of proper sp ecification of plume centroid height when using high resolution meteor ological data for transport studies. Use of the standard coarse grid M RF wind fields to drive the transport model was shown to lead to large errors near the source due to the poor horizontal and vertical resolu tion.