Short-Term Forecasting of drought by use of Standardized Precipitation Index & Probability Markov Chain (Case study: the synoptic station of Qazvin)

Being aware of drought situation is an appropriate tool to manage agricultural activities, water resources and other issues affected by drought. Objective of the present research is to measure drought in the synoptic station of Qazvin based on Standard Precipitation Index (SPI) and short-time forecasting by use of Markov Chain. Probability of occurrence of various situations of short-term droughts was calculated based on monthly precipitation data of Qazvin Synoptic Station through 1996-2013. Results of drought forecasting analysis by use of Markov Chain demonstrated that considering the probability of 45.5 percent in normal situation and first six-month of the precipitation year, 2013-14 may be a transition year from normal condition into wet one with probability of 47.6 percent of the most possibility in the investigated data.