مهندسی منابع آب (Aug 2019)
Tempo-spatial Analysis of Precipitation Waiting Time Duration Changes in Kurdistan Province
Abstract
One of the consequences of global warming and climate change is shifts in tempospatial of important atmospheric parameter precipiation. The aim of this study is detection changes in precipitation waiting time duration in Kurdistan province during recent decades. To doing this research daily precipitation data from 162 synoptic, climatic and rain gauge stations in and out of province during 1/1/1340 to 11/10/1391 extracted from Kurdistan Regional Water Company and meteorology organizations. By geostatistic Kriging method daily precipitation interpolated on 6 6 kilometer and one digital map has been created for each days. Then data over province on the 811 pixels that covers whole of province extracted. One data base in 18914*811 dimensions has been created that locate days on the rows and on the columns pixels. The average waiting time duration calculated for each pixels during different months. The Mann Kendal nonparametric statistics test fitted on the average waiting time duration time series at 90% confidence level. The chages rate estimated by linear least square method. The results showed that waiting time duration has been longer in cold seasons while shorter in warm seasons. The decrease rate of waiting time duration is twice waiting time duration increse. The distribution of significant trend over Kuridstan province show that waiting time duration is longer in semiwestern parts. In contrast in semieastern parts precipitation waiting time duration is shorter.