Statistical properties of 49 years of rainfall rate events |
| |
| Authors: | E Vilar A Burgueño |
| |
| Institution: | (1) Department of Electrical and Electronic Engineering, University of Portsmouth, Portsmouth, England;(2) Department of Astronomy and Meteorology Facultat de Fisica, Universitat de Barcelona, Barcelona, Spain |
| |
| Abstract: | Summary The paper presents a detailed investigation of magnitudes and properties pertaining to the large population of rainfall events recorded during 49 years at the Fabra Observatory in Barcelona. The study includes a statistical analysis of event durationT and rainfall quantityQ together with the statistical rainfall rate parameters:
,
2(R) and maximum Rm within an event. The decorrelation time is also analysed. It is found thatQ, T, and can be well modelled by a lognormal distribution, but
,
2 and Rm are only so for a limited range of precipitation ratesR. The regression analysis between pairs of logarithms of the magnitudes investigated is generally good and a regression coefficient is often better than 0.9. Comparison with published work is also carried out. An attempt is made to discriminate between heavy and non-heavy rainfall rates, and the 50 mm/h threshold is used for the study. The twelve-monthly running average indicates that the rainfall amount has a small increasing trend over the fifty year period. However, this trend is reversed when considering heavy rains. Finally, the return period in years to exceeding a thresholdR within an event is also investigated and the distribution of the population of annual extremes is found to be Gumbel II.With 6 Figures |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
