Four years of daily stable water isotope data in stream water and precipitation from three Swiss catchments

Jana Von Freyberg,Andrea Rücker,Massimiliano Zappa,Alessandro Schlumpf,James W Kirchner,Bjørn Studer

doi:10.1038/s41597-022-01148-1

Abstract

Time series of the natural isotopic composition (2H, 18O) of precipitation and streamwater can provide important insights into ecohydrological phenomena at the catchment scale. However, multi-year, high-frequency isotope datasets are generally scarce, limiting our ability to study highly dynamic short-term ecohydrological processes. Here we present four years of daily isotope measurements in streamwater and precipitation at the Alp catchment (area 47 km2) in Central Switzerland and two of its tributaries (0.7 km2 and 1.6 km2). This data set reveals short-term responses of streamflow isotopes to precipitation events, which otherwise remain obscured when isotopes are sampled weekly or monthly. The observations span the period June 2015 through May 2019, during which several hydrometeorologic extreme events occurred, including a very dry summer in 2018 and below-average snow accumulation in winter 2016/2017. In addition, we provide daily time series of key hydrometeorological variables that, in combination with the isotope data, can be useful for assessing the robustness of ecohydrological models.

Highlights

Background & SummaryStable isotopes of water ( 2H and 18O) are widely used as natural tracers to study hydrological and ecological processes[1,2]
Temporal variations of isotope values in streamflow and precipitation can be compared to estimate the relative contributions of recent precipitation to streamwater or evapotranspiration[3,4]
Other processes that could substantially alter these isotope values, such as evaporative isotopic fractionation, are usually negligible once incoming precipitation has infiltrated into the subsurface[9]

Summary

Introduction

Background & SummaryStable isotopes of water ( 2H and 18O) are widely used as natural tracers to study hydrological and ecological processes[1,2]. Streamwater isotopes were measured in the Alp main stream and in two of its tributaries (Erlenbach and Vogelbach); precipitation isotopes were measured at two grassland locations in the Alptal catchment, in the headwaters at 1228 m a.s.l. and near the outlet at 910 m a.s.l. The dataset includes daily time series of key hydrologic and meteorologic variables, such as daily streamwater and precipitation fluxes, air temperature, relative humidity and snow depth.

Results

Conclusion