عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Drought is a natural disaster that affects the human life due to its significant effects on agricultural and economic sectors. Using the remote sensing technique, drought can be studied through its effects on plants, and it is possible to gain a more accurate and effective modeling of drought. In this study, the efficiency of vegetation condition index in analyzing the agricultural drought was evaluated using the remote sensing facilities for East Azarbaijan province. The data included the MODIS sensor images from Terra satellite between 2000-2011 and the rainfalls from synoptic and climatic stations of the province. To gain the vegetation condition index (VCI) values, the normalized vegetation index (NDVI) values were used. The NDVI derived from the information of the bands 13 &16. According to the VCI values the drought covered more areas in the years 2001, 2008, 2000 & 2009 while it covered less areas in the years 2010 & 2003. To assess the efficiency of the study, the Standardized Precipitation Index (SPI) were calculated from the data of the years 2001, 2008, 2010, 2003, in 9 weather stations and compared with the data collected from VCI maps. According to the SPI index, the years of 2008 & 2001 encountered the highest drought and also the years of 2010 & 2003 had the lowest drought. The results indicate that using the VCI index is an excellent method for evaluating the agricultural droughts through the Remote Sensing. Furthermore, in areas with or without sporadic weather stations this index can be used for estimating drought since the number of sampling points on satellite images exceeds the number of the weather stations.