Cumulative time statistics of surface-point rainfall rates

Abstract

Statistics on rainfall rates near and above the earth's surface are needed in order to estimate the percentage of time of absorption, or scattering of radio waves that affect radio system design and electrospace management. The most useful averaging time for computing such rates is on the order of 1 min or less. This paper extrapolates excessive short-duration precipitation data to provide such statistics from data routinely reported by the National Weather Service. For the 8766 h in an average year, and for a median or random location in any part of the world, the model described here estimates the fraction of time during which t-minute average rainfall rates exceed any given value.