Analysis of Moderate and Intense Rainfall Rates Continuously Recorded Over Half a Century and Influence on Microwave Communications Planning and Rain-Rate Data Acquisition
IEEE Transactions on Communications
This paper is concerned with the statistical investigation of a massive data bank of 49 years of rainfall rate R continuously recorded in Barcelona using a rain-rate gauge with ten seconds response time. With radio communications in mind, the paper addresses and reviews in detail: 1) reliable statistical model for R, 2) number of years required to obtain a database from which to derive a reliable R-distribution, and 3) the CCIR worst-month concept. The research has shown that the generalized
... the generalized Pareto a exp ( -pR)/Rb gives nearly perfect fit for all ranges of R followed closely by the gamma distribution, and the simpler square root (R"*) normal distribution gives excellent fit too. The log-normal distribution was unsatisfactory for R 5 60 mm/h. The spread of the yearly distribution of P ( R ) is cube root normally 'distributed ( [ f ( R ) ] " 3 ) and between 7 and 10 years are required before a reliable average distribution P(R) can he obtained. The study of the P(R) return time in years is also presented. High resolution of P ( R ) is presented looking at the evolution of the annual P ( R ) in terms of the hourly and monthly contributing parts revealing statistical features such as the location in time of rain rates above 50 mm/h. Finally, the study shows that the calendar month contribution to P(R) remains at all times well below the synthetic CCIR worst month and recommendations are then given about its use.