The dataset includes diatom oxygen isotope data for 39 samples from short core EN18232-1, Lake Khamra, and corresponding key geochemical characteristics of the purified lake sediment samples based on Energy-Dispersive X-ray Spectroscopy (EDS) measurements. For each sample (Sample ID) the corresponding core depth (Depth sed top/bottom) and the calculated mean age (Age) are given. EDS measurements were carried out by a JEOL M-IT500HR analytical scanning electron microscope (SEM) with an integrated EDS-system supplied with a Peltier element cooled SD detector (SDD) at AWI Potsdam. The standardless procedure was used according to Chapligin et al. (2012), including 6 repetitions, acceleration voltage of 20.0 kV, magnification of 300 and a measuring time of 30 seconds. All detectable elements are normalized to 100% weight. Elements are given as oxides with weight percentages (in %) and summed up to the total sum (total %) of each sample. The diatom oxygen isotope data was generated in the ISOLAB Facility at AWI Potsdam with a semi-automated laserfluorination line (Chapligin et al., 2010) in combination with a SERCON HS2022 mass spectrometer (https://hdl.handle.net/10013/sensor.4880f572-3c55-4e3e-a2e7-485d9bfa06b2). All δ18Odiatom values are given in per mill (‰) vs. Vienna Standard Mean Ocean Water (VSMOW). The dataset includes the mean of measured δ18Odiatom values (Diatom δ18O mean), the standard deviation (Diatom δ18O std dev) and number of replicates (Repl), as well as the calculated contamination (Contamination in %) and the δ18Odiatom corrected for contamination (Diatom δ18O corrected). Details of the contamination correction and isotope analytics are given in Stieg et al. (2024).

To compute the age-depth model a Bayesian accumulation model within the R package 'rbacon' v2.5.8 (Blaauw and Christen (2011); R version 4.1.1) was used based on the 210Pb chronology.