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Abstract
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Drought is a creepy phenomenon, reversible climate and an unavoidable reality in different climates that is caused by a lack of rainfall over a period of time. Drought is one of the most important natural disasters that has affected many countries, causing many problems including economic, social, political and cultural. And the damaging effects of this phenomenon on the agricultural sector, which is the major consumer of water, can cause a lot of damage. Therefore, with all these interpretations, the first step in managing this phenomenon is to identify and monitor it with valid indicators.
In this study, drought monitoring in Bushehr province based on SPI and VCI indices using MODIS sensors with emphasis on Persian Gulf blue zone was investigated. In this regard, the VCI vegetation status index, a normalized index for drought assessment, was calculated using 55 NDVI time series images of Modis satellite crop growth seasons (January, February and March). Then, drought classes including (severe drought - moderate drought - no drought) were determined for each image. The percentages of each floor area are also given in the charts and tables. Following is the SPI Standard Precipitation Index for 5 stations (Borazjan, Bushehr, Deylam, Dayyer and Jam) to calculate the satellite index and calculated according to SPI Classification Table each year with regard to the amount of rainfall to the most severe drought, severe drought, Moderate drought, roughly normal, moderate humidity, very humid and very wet were classified and then the correlation coefficients of these two indices were evaluated. After identifying the years of drought occurrence, the number of days of rainfall occurrence in these years was extracted and then the parameters were converted into GRAPS software in the form of special scripts. Finally, the produced maps were analyzed in order to study the role of the Persian Gulf moisture and the convections on it. The results of the drought monitoring showed that
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