abstract precipitation is an important variable which is used in definition of drought. based on precipitation amounts, some indices are devised for drought monitoring including, the standardized precipitation index (spi) and the standard index of annual precipitation (siap). each of these drought indices are classified into some classes so that each class descripts a given severity of drought....

Arid and semi arid areas of Balochistan are characterized by low and erratic rainfall and are prone to drought conditions which normally occur every three to four years. Th e prevailing drought is one of the most severe in its magnitude as annual rain (60-150 mm) has been well below average for a continuous period of four to fi ve years in most parts of highland Balochistan. Results from a long...

the effects of climate change, especially due to the increase of greenhouse gasses, have caused lots of problems that have affected different sections of society. one of the most important effects is the increase of natural disasters such as flood, drought, tropical cyclones, raising sea level, dust storm, etc. drought and flood are the most prevalent of these disasters in iran. because of the ...

drought as a climatic phenomenon affected many different environmental issues and generally is associated with the decreasing in average precipitation. evaluation and monitoring of the drought is a fundamental step in proper programming of water resources management. regarding the recent conditions water scarcity in the urmia lake basin, assessment of the drought index in this region is inevita...

iran is located in dry belt of the earth and always involved with drought in different sections. drought has already caused many losses to natural plant cover, agriculture and human society. for drought monitoring, we can use some drought indecies. in this research, the standard index of annual precipitation)siap),sandardized precipitation index (spi) and palmer drought severity index (pdsi) we...