A SYNOPTIC CLIMATOLOGY FOR FOREST-FIRES IN THE NE US AND FUTURE IMPLICATIONS FROM GCM SIMULATIONS

We studied surface-pressure patterns corresponding to reduced precipit ation, high evaporation potential, and enhanced forest-fire danger for West Virginia, which experienced extensive forest-fire damage in Nove mber 1987. From five years of daily weather maps we identified eight w eather patterns that describe distinctive flow situations throughout t he year. Map patterns labeled extended-high, back-of-high, and pre-hig h were the most frequently occurring patterns that accompany forest fi res in West Virginia and the nearby four-stare region. Of these, back- of-high accounted for a disproportionately large amount of fire-relate d damage. Examination of evaporation acid precipitation data showed th at these three patterns and high-to-the-south patterns ail led to dryi ng conditions and all other patterns led to moistening conditions. Sur face-pressure fields generated by the Canadian Climate Centre global c irculation model for simulations of the present (1xCO(2)) climate and 2xCO(2) climate were studied to determine whether forest-fire potentia l would change under increased atmospheric CO2. The analysis showed a tendency for increased frequency of drying in the NE US, but the resul ts were not statistically significant.