Evaluation of perennial reference evapotranspiration (ET o ) over a typical dryland using satellite images: A case study from Uzbekistan

Evapotranspiration (ET) is one of the most significant compartments in the energy and water balance between the atmosphere and the Earth's surface. Global climate change has an impact on the water cycle and can result in an increase in ET from the land surface; nevertheless, an increase in ET can destabilize the macro- and micro-climate at the local and continental levels. In line with this, the purpose of this article is to learn more about the factors that contribute to the high and current reference ET (ET o ) rate of Karakalpakstan (Uzbekistan). MODIS Terra images was used to analyze long-term land cover change. The Google Earth Engine code editor, Erdas Imagine 2020, and ArcMap 10.8 were used to map land cover change and the leaf area index (LAI). Though the Normalized Difference Vegetation Index and the Soil-Adjusted Vegetation Index were used because of their past performance as affirmative measurement techniques for vegetation monitoring. The HargreavesSamani equation was utilized to ET o in this study. Increased crop density in agriculture and the conversion of barren soil to grasslands to rehabilitate the seashore ecosystem of the Aral Sea influenced LAI significantly, according to multifactorial analyses of perennial air temperature, land cover change, solar irradiance, and ET o in a typical dryland of Uzbekistan. However, the extension of LAI in the agricultural area of Karakalpakstan substantially accelerated the ET o rate, which was a key contributor of an increase in crop water demand. We can see that measured solar radiation and ET o were consistent across time by looking at the nearly same quantities for both. As a result, we assume that global climatic changes have no effect in the uncertainty of solar radiation and ET rate.& COPY; 2023 European Regional Centre for Ecohydrology of the Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.