How realistic are water‐balance closure assumptions? A demonstration from the southern sierra critical zone observatory and kings river experimental watersheds

• DOI: 10.1002/hyp.14199
• Publication Date: 2021-04-30T03:55:41Z
• Authors: Mohammad Safeeq; Ryan R. Bart; Norman F. Pelak; Chandan K. Singh; David N. Dralle; Peter Hartsough; Joseph W. Wagenbr...
• Keywords: Water balance; Water storage; Discharge; Catchment hydrology; Closure (psychology)

Abstract The water balance is an essential tool for hydrologic studies and quantifying water‐balance components the focus of many research catchments. A fundamental question remains regarding appropriateness closure assumptions when not all are available. In this study, we leverage in‐situ measurements fluxes storage from Southern Sierra Critical Zone Observatory (SSCZO) Kings River Experimental Watersheds (KREW) to investigate annual errors across large (1016–5389 km 2 ) river basins small (0.5–5 headwater‐catchment scales in southern Nevada. results showed that while long‐term can be closed within 10% precipitation, smaller headwater catchments as much a quarter precipitation remained unaccounted for. detailed diagnosis error using distributed soil moisture top 1 m suggests deeper net groundwater export This imbalance was also found very sensitive timescales over which closures were attempted. While some simple attributed measurement uncertainties, argue broader consideration exchange evaluating hydrological processes at scales, assumption negligible may lead overestimation derived method.