Water isotope values in time series samples (March - October 2020) collected at buoys deployed in northeastern German lake systems

Water isotopes (δ2H and δ18O) were analyzed in samples collected in lakes associated to major riverine systems in northeastern Germany throughout 2020. This sub-dataset is derived from water samples taken at buoys temporarily installed in deep parts of the lake. Samples were taken monthly to bimonthly from March to October 2020. A Limnos water sampler was used to obtain samples from 1 m below water surface. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Water temperatures were measured in similar depths with an Aqua TROLL 600 multiparameter sonde (In-Situ, Fort Collins, CO, USA). The data give information about the seasonal isotope amplitude in the sampled lakes and about spatial isotope variability in different branches of the associated riverine systems.