Effects of climate change on the thermal regime of a reservoir

Thermal stratification is strongly associated with hydrodynamics, and plays an important role in the dynamics of water quality and the ecosystem of stratified water bodies. Changes in the climate or hydrological conditions can alter thermal regimes. This study aims to investigate the effects of climate change on the thermal structure of a reservoir. To quantify these effects, a hydrodynamic and water quality model was applied to the Latian dam reservoir in Iran. The outputs of the Canadian global climate model version 3 for B 1 , A 1 B and A 2 scenarios were used to obtain future (year 2100) air temperature trends. Results from these scenarios were compared with those of base conditions to investigate the effects of climate change. The maximum surface water temperature increase was about 2°C for the S2 scenario, which was the scenario with the highest air temperature increase (5·7°C). The increase in water temperature indicated some important effects on thermal stratification; for example, thermal gradient across the metalimnion was increased. It was also inferred that the Latian dam was severely sensitive to inflow variations as well as temperature changes.