5D.4
Hurricane Forecasting using Adaptive Unstructured Grids
David P. Bacon, SAIC, McLean, VA; and N. N. Ahmad, Z. Boybeyi, S. G. Gopalakrishnan, M. S. Hall, P. C. S. Lee, and R. A. Sarma
The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric simulation designed around an adaptive unstructured grid. Originally designed for high resolution, high fidelity atmospheric dispersion, the adaptive grid of OMEGA permits the true multiscale simulation or forecast of hurricanes. In the fall of 1999, OMEGA was used for the first time to examine the structure and evolution of a hurricane (Floyd, 1999). Since that time, over 20 forecasts have been performed in either research or operational mode. The OMEGA mean track error for all of these forecasts of 104, 142, and 312 km at 24, 48, and 72 hours, respectively. Three of the 20 forecasts went out to 96 hours, two for Hurricane Georges (1998) and one for Floyd. The 96-hour track error was less than 400 km in one case and less than 100 km for the other two. This accuracy was to a great extent the result of the adaptive grid of the OMEGA model. The figure shows a simulation of Floyd with dynamic adaptation, where the grid automatically tracks the pressure minimum. The inset of this figure shows the location of the high-resolution region 48 hours into the simulation. (The yellow dots show the observed storm track and provide a reference for the quality of the track forecast.)
This paper will present a quick overview of the OMEGA system as applied to operational hurricane track forecasting including the automatic dynamic adaptation of the grid.
Supplementary URL: http://vortex.atgteam.com
Session 5D, Tropical Cyclone Prediction III (Parallel with Sessions 5A, 5B, & 5C)
Tuesday, 30 April 2002, 11:00 AM-12:30 PM
Previous paper Next paper
Extended Abstract (1.1M)