Structural characteristics of annual precipitation data in Jordan

Thirteen meteorological stations distributed across Jordan are selected in order to analyze the structure of annual precipitation data for the country. The length of data, for all stations, is 50 years, covering the common period 1953-2002. The analysis is based on a series of tests designed to determine if the annual total precipitation data taken from each station are consistent, random, and trend free. Consistency is defined simply using the classical doublemass curve, and a non-parametric test is used to determine randomness. The Fisher test is also employed to test for randomness of the series. In order to determine if the data are trend free, a simple linear trend model, as well as the Spearman Rank Order Correlation test, is used. Jump analysis is also performed following application of the segmentation procedure, and finally, the probability distribution fitted to the data set is determined using the Probability Plot Correlation Coefficient test. The study concludes with a description of the structural characteristics and temporal and spatial variation of annual precipitation data in Jordan, together with possible projections for the future.