LONG-TERM VARIABILITY OF MONTHLY TOTAL PRECIPITATION

A methodology was developed to quantify long-term temporal variability of monthly total precipitation. Ninety-three years of data from four weather stations on the Florida peninsula were used. This peninsula, c overed by a single 8 degrees x 10 degrees grid of the NASA/GISS atmosp heric GCM, is a transitional climatological region, influenced on a se asonal basis by mid-latitude continental fronts, convective thundersto rms and tropical disturbances. Traditional statistical descriptors sug gested that the distribution of monthly total precipitation was highly non-Gaussian. A gamma probability density function was successfully f it to the historical data and used to investigate the possible presenc e of long-term trends. These findings suggested that the distribution of monthly total precipitation rather than the mean and standard devia tion, should be used in weather and climate model development and vali dation. This methodology also may be applicable to sub-grid scale spat ial variability of monthly precipitation.