Quantifying the contribution of evaporation from Lake Taihu to precipitation with an isotope-based method. Issue 3 (4th May 2022)

• Record Type: Journal Article
• Authors: Hu, Yongbo; Xiao, Wei; Wang, Jingyuan; Welp, Lisa R.; Xie, Chengyu; Chu, Haoran; Lee, Xuhui
• Is Part Of: Isotopes in environmental and health studies. Volume 58:Issue 3(2022)
• Page Start: 258
• Page End: 276
• Publication Date: 2022-05-04
• Subjects: China -- evaporation -- hydrogen-2 -- lake -- modelling -- moisture -- monsoon -- oxygen-18 -- recycling -- water; Isotopes -- Periodicals; Radioisotopes -- Periodicals; Environment -- Periodicals; Isotopes -- Periodicals; Medicine -- Periodicals; Radioisotopes -- Periodicals; 541.388
• DOI: 10.1080/10256016.2022.2056599
• Languages: English
• ISSNs: 1025-6016

Abstract

ABSTRACT: Moisture recycling plays a crucial role in regional hydrological budgets. The isotopic composition of precipitation has long been considered as a good tracer to investigate moisture recycling. This study quantifies the moisture recycling fractions ( f r ) in the Lake Taihu region using spatial variations of deuterium excess in precipitation ( d P ) and surface water vapour flux ( d E ). Results show that d P at a site downwind of the lake was higher than that at an upwind site, indicating the influence of lake moisture recycling. Spatial variations in d P after sub-cloud evaporation corrections were 2.3, 1.4 and 3.2 ‰, and d E values were 27.4, 32.3 and 31.4 ‰ for the first winter monsoon, the summer monsoon and the second winter monsoon, respectively. Moisture recycling fractions were 0.48 ± 0.13, 0.07 ± 0.03 and 0.38 ± 0.05 for the three monsoon periods, respectively. Both using the lake parameterization kinetic fractionation factors or neglecting sub-cloud evaporation would decrease f r, and the former has a larger influence on the f r calculation. The larger f r in the winter monsoon periods was mainly caused by lower specific humidity of airmasses but comparable moisture uptake along their trajectories compared to the summer monsoon period.