Determination of an urban evapotranspiration index based on new Penman-Monteith framework. A Case Study for Belgrade Area

Abstract

The water cycle is dependent on the ability of urban surface water to evaporate. Understanding how the at-mosphere interacts with this process is very important. It is also difficult to determine how much water is evapotran-spiration coming from urban areas due to their varying surface characteristics. A cloud cover's effect on solar radia-tion can determine how much reaches the surface of the Earth. In addition to shielding surface water, clouds can also help reduce the surface temperature gradient of the water. The paper noted that the enhanced multi-source model can be used to calculate the urban evapotranspiration of Belgrade urban area. The urban model incorporated Monteith's framework to evaluate the data from a metrological station regarding the cloud cover's data for a specific period. It then considered the various factors that affected the evaporation process, including the wind speed, air temperature, and moisture content of soil. The vegetation cover and leaf area index are also considered to calculate the overall effect of evaporation. The urban model developed by the new Penman-Monteith framework performed better than its predecessor in calculating urban evapotranspiration. The study demonstrates how urban water usage contributes to the urban heat island issue, as well as how cloud cover can also affect this phenomenon.