A major new study led by Swansea University has shown that upstream river management rather than local rainfall is the primary driver of one of the world's most important wetlands.
The future of Iraq's Mesopotamian Marshes depends far more on the water flowing from the Tigris and Euphrates rivers than on local rainfall, according to new research published in Nature Scientific Reports, analysing more than two decades of satellite observations.
The Mesopotamian Marshes, located in southern Iraq, are one of the most important wetland regions in the world, designated a UNESCO world heritage site, and home to unique civilisation and biodiversity.
Despite extensive restoration efforts following the 2003 reflooding of the marshes, the ecosystem remains under increasing pressure from climate change, upstream dam construction, and regional water management.
In the new study, researchers examined changes in vegetation and surface water across the marshes from 2000 to 2023 using multiple satellite datasets alongside rainfall and river flow records. The analysis combined data from NASA MODIS, EU Copernicus Sentinel-2, JRC Global Surface Water, as well as streamflow and precipitation observations to identify the factors controlling the marshes' long-term health.
The researchers found that:
The findings underscore the importance of international cooperation among countries sharing the Tigris-Euphrates river system to ensure sufficient water reaches the marshes during periods of drought.
Lead author Akram Alqaraghuli, who is completing a PhD at the Global Environmental Modelling and Earth Observation (GEMEO) group within Swansea University’s Department of Geography, said: “Our results show that maintaining river flows is essential for preserving the Mesopotamian Marshes, and also the key role of the wetlands in maintaining temperature in the region.”
Professor Peter North , co-author and supervisor of the research said: “Long-term satellite records are increasingly allowing us to separate human intervention from climate impact on the environment. This study can contribute to management of one of the world’s key resources and highlights the need for international cooperation.”
The project has support from the Iraq Government, Google, UK NERC National Centre of Earth Observation , and the UK Wildlife and Wetlands Trust (WWT).
Scientific Reports
Observational study
Not applicable
The impact of climate factors and surface water management on the Mesopotamian Marshes for the period 2000–2023
15-Jul-2026
The authors declare no competing interests.