Affiliations 

  • 1 Department of Civil and Environmental Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
  • 2 Discipline of Civil Engineering, School of Engineering, Monash University (Malaysia Campus), Malaysia
  • 3 Department of Fire and Disaster Prevention, Konkuk University, 268 Chungwon-daero, Chungju 27478, Republic of Korea. Electronic address: sangyeob@kku.ac.kr
  • 4 Department of Ecology, Jinan University, Guangzhou 510632, China
Sci Total Environ, 2024 May 15;925:171839.
PMID: 38513843 DOI: 10.1016/j.scitotenv.2024.171839

Abstract

Water availability needs to be accurately assessed to understand and effectively manage hydrologic environments. However, the estimation of evapotranspiration (ET) is prone to errors due to the complex interactions that occur between the atmosphere, the Earth's surface, and vegetation cover. This paper proposes a novel approach for analyzing the sources of inaccuracy in estimating the annual ET using the Budyko framework (BF), particularly temporal variability in precipitation (P), potential evapotranspiration (EP), runoff (R), and the change in soil storage (ΔS). Error decomposition is employed to determine the individual contributions of P, R, EP, and ΔS to the ET error variance at 12 locations in the state of Illinois using a dataset covering a 22-year period. To the best of our knowledge, this study represents the first BF-based investigation that considers R in the error decomposition of the predicted ET variance. The ET error variance increases with the variance in the P and R in Illinois and decreases with the covariance between these two variables. In addition, when accounting for ΔS in the BF, the scenario in which ΔS affects the total available water (i.e., P) is reliable, with a low prediction error and a 13.87 % lower root mean square error compared with the scenario in which the effect of ΔS is negligible. We thus recommend the inclusion of ΔS and R as key variables in the BF to improve water budget estimations.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.