Frequency of Drought Investigation on Karkhe Basin in Lorestan Province

Drought is called to a long period of time that an insufficient amount of rainfall to be revealed and dry weather lasts for a long time. Drought is abnormally low and long term moisture that has adverse effects on plants¡ animals and human. In this study¡ the accepted definition of climate drought is periods of precipitation that is lower than average. Actually¡ this is” the comparison between lack of rainfall and its long-term average”. Because of the importance of drought in water projects¡ in this study¡ we investigate the frequency of drought for period of last thirty-years ago on Karkhe basin in Lorestan province. After checking the data¡ or data quality of statistical errors was to evaluate quantitative data. To reconstruct the missing data¡ Aystgah Ha with full statistics¡ position and altitude of the stations with incomplete statistics were used. Drought frequency is the most important feature for studying in a region that considered which can be different in scales of time (yearly¡ monthly¡ quarterly). In this study¡ we investigate rainfall data from eight meteorological stations for thirty years in KARKHE basin in different months to evaluate drought frequency. These data about the amount of thirty years of the rainfall have been prepared from meteorological of LORESTAN province. Although¡ the operation of review and restore data is in processing. Buffering method and Excel software was used for the project.