Evaporative fractions and elevation effects on stable isotopes of high elevation lakes and streams in arid western Himalaya

Deuterium‐excess determination of evaporation to inflow ratios of an alpine lake: Implications for water balance and modeling

“…Shallow lakes usually have higher E/I ratios (Brooks et al, 2014;Wolfe et al, 2007). However, E/I ratios of two shallow lakes were lower than the E/I ratios of adjacent deep lakes in western Himalaya (Biggs et al, 2015), which was contrary to observations in lakes of other regions (Brooks et al, 2014), indicating the complex hydrological regime in high-elevation regions and the need for sitespecific research.…”

“…In the absence of in situ measurements, isotopes in atmospheric water vapor are usually assumed to be in isotopic equilibrium with local precipitation in models of the lake water balance (Biggs et al, 2015;Gibson et al, 2008;Isokangas et al, 2015;Skrzypek et al, 2015;Yang et al, 2016). This assumption was not always valid especially in arid and semi-arid regions (Gibson et al, 2016;Horita, Rozanski, & Cohen, 2008;Mayr et al, 2007).…”

“…In low latitude (Kebede et al, 2009) or large lake regions (Jasechko et al, 2014) where the boundary layer is perturbed significantly by moisture evaporated from lake surface, atmospheric feedback (humidity buildup) needs to be considered (Gat, 1996;Gibson et al, 2016). In regions with low humidity, an alternative ε K -h relation may help to solve the problem of atmospheric feedback (Biggs et al, 2015;Zuber, 1983). A detailed review was presented recently by Gibson et al (2016).…”

“…The ratio of evaporation to inflow ( E / I ) is a key parameter to indicate the water balance for open water bodies and has been applied widely to study lake evaporation in different geographical and climatic scenarios (Biggs et al, ; Gibson, Birks, & Yi, ; Kebede, Travi, & Rozanski, ; Mayr et al, ). In low‐altitude regions, E / I ratio can vary due to the influence of groundwater (Isokangas, Rozanski, Rossi, Ronkanen, & Kløve, ), seasonal flood (Brock, Yi, Clogg‐Wright, Edwards, & Wolfe, ), wetland (Gibson, Prepas, & McEachern, ), or chains of lakes (Gibson & Reid, ).…”

When to conduct an isotopic survey for lake water balance evaluation in highly seasonal climates

“…For hydrogen, we used the ε K -h relationship presented in Zuber (1983) to calculate ε K , which produced a better match between E/I from δ 18 O and δD than the ε K -h relationship in Gonfiantini (1986) in regions with low humidity. The ε K -h relationship of Zuber (1983) has been successfully used in previous studies (Biggs et al, 2015;Cui et al, 2017). Temperature, h, and δ A were weighted by monthly evaporation flux according to Gibson, Birks, and Edwards (2008).…”