Dead Sea Warming and the Origin of Salt Giants

Emmanuel Guillerm , Tim K Lowenstein, Véronique Gardien, Fabian Bärenbold, Damien Bouffard, Achim Brauer, Frédéric, Caupin

Episodically in Earth’s history, marine basins became hydrologically restricted, forming “salt giants,” yet the mechanisms driving their formation remain debated. The modern Dead Sea, undergoing restriction from anthropogenic inflow diversion, shows rapid lake-level decline and salt precipitation. We present a physical model coupling energy and mass fluxes in hypersaline waterbodies. The model reproduces the observed ~3 °C Dead Sea water-column warming since 1979. By 2600, the Dead Sea will drop ~180 m, and warm by ~10 °C to ~20 °C depending on global CO2 emissions. A fully restricted eastern Mediterranean under modern climate conditions would undergo 20 °C warming and kilometer-scale drawdown within a few millennia. Once isolated, large basins enter a positive feedback loop between warming and water loss that drives precipitation of halite and potash salts without requiring hot, arid climates. Because paleobrine warming tracks brine shrinkage, vertical paleotemperature trends in evaporites may record drawdown rather than paleoclimate.