Oxygen and hydrogen isotopes in streams and precipitation and young water fractions across the Andes mountains and Amazon floodplain

This dataset includes oxygen (d18O) and hydrogen (d2H) isotope ratios in streams and precipitation across the Andes mountains and Amazon foreland floodplain in southern Perú. Samples were collected approximately twice monthly from 2015–2020. Data presented here can be used to calculate the fraction of streamflow comprised of recent precipitation (e.g., the young water fraction sensu Kirchner, 2016). These data are used in Burt et al., 2023 to understand how precipitation moves through watersheds across the geomorphic gradient of the Andes mountains and Amazon floodplain. We also provide a Matlab script that will calculate flow-weighted young water fractions and carry out a bootstrap resampling routine to generate uncertainty intervals (e.g., Figure 8 from Burt et al., 2023)