Surging temperatures across Türkiye are replacing precipitation deficits as the primary driver of snow droughts, driving early snowmelts and threatening summer water supplies in 25 critical basins, a study has revealed.
Led by Harun Aslan alongside Istanbul Technical University Eurasia Institute of Earth Sciences Director Tolga Görüm, Abdullah Akbaş and Ankara University’s Seçkin Fidan, researchers analyzed 1990-2024 European Centre for Medium-Range Weather Forecasts data. Published in the Hydrological Sciences Journal, the study evaluated basins including the southeastern Euphrates-Tigris and southern Ceyhan.
A post-2007 transition to heat-dominated droughts created dry, warm and warm-dry categories. Warm-dry conditions are the most severe, hitting 15 basins, covering 13 percent of the area, slashing flow anomalies by 36 percent. Warm droughts affect 8 percent, reaching 14 percent in Ceyhan, 12 percent in central Kızılırmak and 11 percent in Seyhan. Dry droughts affect 3 percent.
Losses peak below 2,000 meters, where 70 percent of Türkiye’s snow naturally stores. Warm-dry periods destroy 79 percent of snow water equivalent, reaching 76 percent depletion between 500 and 2,000 meters. Snowmelt constitutes 44.7 percent of total flows.
“It is no longer just about how much water we have, but when this water is available,” Akbaş said. Drought involves how long snow stores water, Aslan said.
Türkiye relies on eastern mountainous snowfall to feed agricultural irrigation and hydroelectric dams during dry summers. Climate shifts force authorities to strengthen basin-based management.
