Document Type : Original Article
phd of climatology at Sistan and Baluchestan university
phd student of climatology at Mohaghegh Ardabili university
Awareness of vegetation and its health represents the climate of each place. Access to field data is usually difficult and limited to study and monitor vegetation on a global and regional scale. Also, estimating vegetation in the usual way, which includes an overall estimate of vegetation, is both time-consuming and does not provide very accurate information. Therefore, remote sensing is a very useful method by providing a wide view of the area, which is superior to other methods. In this study, the 16-day data of the Normal Vegetation Differential Index (NDVI) of MODIS Aqua Iran were downloaded from the NASA website between 3/20/2003 to 3/20/2019. Then, based on nearly 15 billion pixels, the long-term and annual average of NDVI Iran was calculated. Considering that NDVI values more than 0.2 indicate vegetation, the average annual vegetation of Iran was calculated. Finally, the relationship between vegetation and rainfall in Iran was investigated. The results showed that in 1387, due to water shortage and meteorological drought conditions, Iran's vegetation reached its lowest value, while in 1397, due to heavy rainfall and wet conditions, Iran's vegetation reached the highest amount in the period The study has arrived. The results also showed that in the last two decades, due to increased rainfall, the range of vegetation in Iran has increased.