Simulation of Evaporation Capacity and its Sensitivity to Climate Change

摘要

Coupling between GCMs (general circulation models) and watershed hydrological model is a main approach to studying impacts of climate change on hydrology and water resources, which needs a large quantity of meteorological data including temperature, precipitation, and potential evaporation. As a key component of hydrological cycle, potential evaporation plays an important role in hydrological simulation. Taking Zhengzhou station as a case, relationship between potential evaporation and temperature, precipitation was analyzed, and in further, sensitivity of potential evaporation to climate change was studied by adopting hypothetic climate scenario. And result shows that potential evaporation is closely related to the temperature and precipitation. The established potential evaporation estimation formula considering factors of rainfall and temperature receives better simulation accuracy than Gao' s equation and only temperature-based exponential formula. Thereby, it' s qualified to be input of hydrological model for future hydrological assessment. The sensitivity of evaporation capacity to temperature change is higher than that to precipitation change. With the decrease of precipitation, temperature has a significant effect on evaporation capacity.