Executive summary
A prolonged five-year drought affecting Iran and the Euphrates–Tigris river basin reached severe levels in 2025, placing acute pressure on water resources, agriculture and energy systems. World Weather Attribution finds that human-induced climate change increased the severity of drought conditions, while long-standing socio-economic water stressors substantially amplified impacts. The analysis shows how climate change and water governance failures interact, turning meteorological drought into systemic risk.
What happened
From around 2020 to 2025, large parts of Iran and the Euphrates–Tigris basin experienced persistent below-average rainfall combined with high temperatures. River flows declined, reservoirs fell to critically low levels and groundwater extraction intensified. By 2025, water shortages were affecting agriculture, electricity generation and domestic supply, contributing to food insecurity and social stress across the region.
Drought conditions were not confined to a single season but accumulated over multiple years, reducing the capacity of natural and managed systems to recover. This prolonged duration was a key factor in the severity of impacts observed.
What the attribution analysis found
The attribution study concludes that human-caused climate change increased the severity of the drought by raising temperatures and enhancing evaporative demand, drying soils and surface waters more rapidly than would have occurred in a cooler climate.
While rainfall deficits played an important role, higher temperatures significantly worsened drought impacts by increasing water loss from soils, crops and reservoirs. The analysis shows that similar rainfall shortfalls in a pre-industrial climate would have resulted in less severe drought conditions.
The study also highlights that uncertainty remains in quantifying precise probability changes for multi-year droughts, but the direction of influence from climate change is clear: warming is intensifying drought impacts across already water-stressed regions.
The role of socio-economic water stress
A central finding of the analysis is that climate change acted alongside, and interacted with, existing socio-economic stressors. Long-term over-extraction of groundwater, upstream dam construction, inefficient irrigation practices and rapid population growth reduced resilience to prolonged dry conditions.
In many areas, water demand already exceeded sustainable supply before the drought began. Climate change therefore acted as a risk multiplier, pushing fragile water systems beyond critical thresholds.
How climate attribution fits into drought risk reporting
Climate attribution helps distinguish between meteorological drought drivers and the factors that convert drought into crisis. In this case, attribution clarifies that climate change increased drought severity, but governance, infrastructure and demand management determined how damaging the drought became.
This distinction is crucial for risk assessment: reducing vulnerability can significantly lower impacts, even as climate hazards intensify.
Why this matters for organisations
For governments, utilities, agribusinesses and investors operating in the region, the findings underline that water scarcity is no longer an episodic risk but a chronic, climate-amplified threat. Reliance on historical hydrological conditions risks underestimating future water shortages, supply disruptions and social instability.
How to use this in your own risk work
Organisations should incorporate climate-adjusted drought scenarios into water stress testing, assess dependence on vulnerable river basins and groundwater sources, and evaluate exposure to cascading risks across food, energy and social systems. Reducing demand, diversifying water sources and planning for prolonged drought should be treated as core resilience priorities.
Source
World Weather Attribution (2025). Human-induced climate change compounded by socio-economic water stressors increased severity of 5-year drought in Iran and the Euphrates and Tigris basin.
https://www.worldweatherattribution.org/human-induced-climate-change-compounded-by-socio-economic-water-stressors-increased-severity-of-5-year-drought-in-iran-and-euphrates-and-tigris-basin/