Background and Objective: this study investigates vegetation drought in East Azerbaijan Province using infrared imagery from the S-NPP JPSS sensor, as vegetation conditions are highly sensitive to rainfall fluctuations and drought is a recurring global phenomenon.

Materials and Methods: visible and infrared images from April 1st to the end of July (weeks 13-26 AD) between 2013 and 2021 were analyzed to assess vegetation status and varying drought levels. Weekly averages of vegetation indices were used to detect changes and fluctuations. The monthly average Standard Precipitation Index (SPI) for East Azerbaijan Province was calculated from monthly precipitation data collected at six synoptic meteorological stations: Ahar, Kalibar, Maragheh, Mianeh, Sarab, and Tabriz. Correlations between average NDVI, VCI, TCI, VHI, and SPI were estimated to determine the relationship between precipitation and vegetation indices.

Results: the correlation between the Standardized Precipitation Index (SPI) and NDVI, VCI, TCI, and VHI was 0.0037, 0.0048, 0.174, and 0.150, respectively. TCI exhibited the strongest correlation with SPI, making it a suitable method for combining remote sensing and meteorological data to assess vegetation conditions in East Azerbaijan province. The most intense vegetation droughts occurred in the western and central regions in 2013 and 2015, and province-wide in 2021. SPI calculations indicated below-normal precipitation during July, August, and September. Overall, the VHI was determined to be the most effective satellite-based index for monitoring vegetation drought in the study area.