Spatial-Temporal Analysis of Dam Construction on Climate Change (Temperature and Relative Humidity)

The artificial lakes that form behind the dams create a considerable level of evaporation that can have significant effects on the microclimate (the area around the dam). If other environmental factors for precipitation are provided, this increase in the volume of atmospheric moisture can affect the temporal and spatial distribution of rainfall. In this research, the effects of the regional climate in the downstream area of Taleghan are studied by examining different climatic parameters in the period before and after the construction of the dam. In general, the construction of Taleghan Dam has many advantages such as lowering the average annual temperature, increasing relative humidity, supplying river water in the rainy season, and even signs of increasing light rainfall in the downstream region. Negative effects can also be seen in the downstream areas, such as imbalance and changes in the amplitude of fluctuations in the values of various parameters, or the warming of hot seasons and the cooling of cold seasons. In general, changes along the river downstream can be intensified or adjusted, but these effects are reduced by moving away from the river bank. In this study, meteorological, hydrometric, vegetation, and soil moisture parameters are analyzed separately. Then the changes in the extremes of these parameters are investigated. Finally, the changes resulting from the construction of Taleghan Dam in spatial and temporal dimensions are revealed by defining a composite index.