Drought is one of the natural disasters, which drastically influences agroecosystem services. In this study, the spatio-temporal pattern of agricultural drought intensity and frequency (during 2001 to 2023) was evaluated in the agricultural land, Khorasan Razavi Province, Iran, using time-series-based satellite imagery. For this, three satellite-derived indices including the Temperature Condition Index (TCI), Vegetation Condition Index (VCI), and Vegetation Health Index (VHI) were used. Moreover, the Standardized Agricultural Drought Frequency Index (SADFI) was introduced as a novel standardized index to map the frequency of agricultural drought over time and space. SADFI is a weighted drought severity frequency index that represents the average frequency of drought classes over a given period to map the frequency of agricultural drought over time and space. Results indicated that 2008 was the driest, while 2019 and 2020 were the wettest years during the 23 years studied. The combined SADFI map also revealed that a large portion of the mid-latitude agricultural lands in the province experienced no significant drought during the study period. Spatial analysis using Global Moran’s I (0.371) and Local Indicators of Spatial Association (LISA) indicated meaningful spatial patterns in vegetation health. The LISA cluster maps recognized healthy (high-high) and stressed (low-low) zones, while high-low and low-high outliers showed localized anomalies, possibly stemming from anthropogenic or microclimatic factors. These findings emphasize the importance of spatial management strategies to improve vegetation resilience in vulnerable regions.

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