The scaling law relating world point-precipitation records to duration

In order to understand the remarkable six-orders of magnitude scaling law underlying worldwide point-precipitation records, we analyse precipitation data from a wide range of stations worldwide. The analysis shows that single-exponent scaling laws exist only for single stations experiencing extremely high precipitation. This analysis, and a consideration of the sequence of earlier published precipitation records, leads us to conclude that record precipitation exists because of an optimization of all factors leading to precipitation. This idea is incorporated into a scheme for simulating the record-duration curve for precipitation, which utilizes only the probability distribution function for precipitation amounts, the temporal autocorrelation of precipitation and a starting record-duration point. The simulation suggests record precipitation is asymptotically independent of most underlying physical processes. Copyright (C) 2004 Royal Meteorological Society.