كاربرد نمايه هاي مبتني بر بارش در مطالعه خشكسالي ها و ترسالي ها

The application of rainfall based criteria in studying of drought and wet years (Case study :East Azarbaijan province)

In this research the data relating to the annual precipitation have been studied for Eastern Azerbaijan province in a time period of 43 years and with the purpose of analysis and modeling of precipitation and calculation of droughts and wet years.With quantitative patterns, and also the differentiation of wet, normal and dry years the different rainfall based indices has been applied. Also the Standardised Precipitation Index is recognised as a better quality model compared to the other models applied in this research, i.e., Nitzehe model, and Dependable Rainfall (DR.). The results of this study prove the occurrence of drought phenomenon in all stations generally showing a degree of weakness or effectiveness. In terms of the classification of the annual wet and dry seasons, usually normal precipitation in various dry years and wet years can be seen and the normal years have more stability and continuity compared to wet years and droughts.