Although the Urmia Lake has undergone remarkable drought conditions within the past decades mainly due to climate change, drought studies covering the entire Urmia Lake Basin and all drought aspects are lacking. The present study investigated the spatial and temporal drought conditions in the Urmia Lake Basin for the past (1988–2017) and future (2021–2050 and 2051–2080) periods using five general circulation models (GCMs) under the IPCC (Intergovernmental Panel on Climate Change) scenarios RCP 2.6, RCP 4.5, and RCP 8.5. The standardized precipitation index (SPI) and standardized precipitation and evapotranspiration index (SPEI) were compared. The SPEI predicted more drought events than the SPI, and it seemed to be a more suitable drought index than the SPI for the basin. In general, the future periods would encounter less drought conditions in terms of significant drought trends and duration than the observed period under all scenarios, but the frequency of quarterly severe drought events in the future periods would be higher than in the observed period. Furthermore, the stations Urmia (western bank) and Tabriz and Maragheh (eastern banks) would face the highest frequency of different types of quarterly drought events in the future periods compared with the observed period. The predicted high frequencies of drought events for the future periods can intensify the current low water level situation of the Urmia Lake, which seriously threatens all types of ecosystems in the basin. Therefore, serious actions need to be taken into account for efficient ecosystem and water resources management in the basin.

It is very important to determine the irrigation water requirement (IR) of crops for optimal irrigation scheduling under the changing climate. This study aimed to investigate the impact of climate change on the future IR and yield of three strategic crops (winter wheat, barley, fodder maize) in the semi-arid Qazvin Plateau, Iran, for the periods 2016–2040, 2041–2065, and 2066–2090. The Canadian Earth System Model (CanESM2), applying IPCC scenarios rcp2.6, rcp4.5, and rcp8.5, was used to project the monthly maximum and minimum temperatures and monthly precipitation of the region. The results indicated that the maximum and minimum temperatures will increase by 1.7 °C and 1.2 °C, respectively, under scenario rcp8.5 in the period 2066–2090. The precipitation will decrease (1%–13%) under all scenarios in all months of the future periods, except in August, September, and October. The IR of winter wheat and barley will increase by 38%–79% under scenarios rcp2.6 and rcp8.5 in the future periods. The increase in the IR of fodder maize will be very slight (0.7%–4.1%). The yield of winter wheat and barley will decrease by ~50%–100% under scenarios rcp2.6 and rcp8.5 in the future periods. The reduction in the yield of maize will be ~4%. Serious attention has to be paid to the water resources management of the region. The use of drought-tolerant cultivars in the region can be a good strategy to deal with the predicted future climatic conditions.

The southern Mediterranean region is among the most vulnerable areas to climate change globally. However, in this region, there is a need to further understand the complex interactions between climate, vegetation, and crops to fully assess the combined impacts of extreme climate events on the agricultural sector. Using daily Normalised Difference Vegetation Index (NDVI) data, we evaluated trends across 15 vegetation phenology indicators between 1982 and 2019 and analysed their links to land‐use land‐cover changes. We found significant increases in the maximum value of NDVI (MaxV), length of growing seasons (LengthGS), and duration from crop emergence to anthesis (BMaxT), particularly within croplands. These changes positively correlated with regional crop production, especially in coastal and interior plains where croplands and forests are expanding. Conversely, southern areas bordering the Sahara showed declining MaxV and an expansion of sparsely vegetated areas. We then conducted a comprehensive seasonal trend analysis of climatic stresses and discussed how they align with recent trends in key phenological indicators. Coastal and interior plains experienced wetter conditions throughout the year, ensuring sufficient water during the growing season. Meanwhile, areas bordering the Sahara had wetter autumns and winters but drier springs and summers. Additionally, the region experienced warmer conditions from spring to autumn, with fewer cold wave events. Analysing the frequency and duration of compound extreme events, we observed a trend toward more light to moderate dry/hot days in spring and autumn and light to extreme wet/hot days from summer to autumn. These conditions are significantly correlated with increased MaxV, improved crop productivity, and extended LengthGS and BMaxT. These findings may serve as early indicators of how future climate changes could impact crop production, highlighting regional risks and opportunities to guide informed decision‐making and development of adaptive strategies in the southern Mediterranean region.

The agriculture sector is sensitive to changes in weather and climate, notably extreme events. Extreme variations in weather conditions throughout a growing season led to changes in phenological features of vegetation and crops and cause variations in harvest, and, generally, the impact could be large in terms of production amounts and then food security in the region. The last version of the Intergovernmental Panel on Climate Change report (IPCC) highlighted the southern Mediterranean region as a hot spot and one of the most vulnerable regions in the world. While numerous studies have addressed changes in climate extremes throughout the world, very little research has been conducted in the southern Mediterranean region concerning the seasonal concurrence of climate extremes, and their evolutions in recent decades. Moreover, understanding the impacts of these changes on vegetation phenology is crucial in the region, but this is yet to be studied.This study evaluates the impact of climate extremes on vegetation phenology in the southern Mediterranean region over the last 40 years. Firstly, the trends of 15 phenological vegetation indicators (e.g., length of the growing season, maximum Normalized Difference Vegetation Index [NDVI] value/time, onset/offset times, green upslope, brown downslope, etc.) are examined using National Oceanic and Atmospheric Administration [NOAA] satellite images and the modified Mann-Kendall trend test. Secondly, we examine how recent trends in vegetation phenology compare with those observed in various heat-related indices (heat wave characteristics), water-related indices (Standard Precipitation Index [SPI], Standard Precipitation Evapotranspiration Index [SPEI], Extreme Precipitation, Wet/Dry spells), and compound indices (Dry-Cold, Dry-Hot, Wet-Cold, Wet-Hot events) calculated using the ERA5-land dataset. Finally, we examine the relative importance of each climate indicator in explaining multi-year changes in vegetation phenology. As such, this study not only identifies the areas with higher risk and vulnerability for vegetation and crops in the last years but also identifies potential predictors for seamless seasonal-to-decadal forecasts of agrometeorological risks across the region.