The impacts of drying of Lake Urmia on changes of degree day index of the surrounding cities by meteorological modelling

The Lake Urmia, the largest lake in Iran and the second largest saline lake in the world, is currently faced with the threat of drying up. In the last two years, it experienced an increase in its water level, leading researchers to compare different situations. In this study, using The Air Pollution Modelling software, two scenarios, one of the lake being full of water and another of the dry lake, were projected in order to simulate changes in energy demand for four cities located in the neighbourhood of the lake. The main results, based on a dry lake scenario, showed a decrease in weather temperature during the cold season and an increase during the hot season, particularly in the day time, in respect of a full level of water in the lake. Because of this, there was an increase in energy demand for cooling degree day (CDD) for daily hours of the hot months and for heating degree day (HDD) demand in the night hours of the cold months. In particular, the overall average annual increase for HDD and CDD in the entire studied area will increase to 140.56° and 105.90° by day, respectively. At the same time, a significant variation of relative humidity in contraposition to temperature will occur; therefore, the thermal comfort conditions of the studied cities are expected to be worse. Finally, future research works must be done to predict the expected energy consumption in the next decades in accordance with the procedure developed.