High-resolution stable water isotope composition of firn core OH-12 from Plateau Laclavere, northern Antarctic Peninsula

The firn core OH-12 was retrieved from Plateau Laclavere, a small ice cap on the northernmost end of the Antarctic Peninsula at about 1090 m above sea level in January 2016. The core was drilled down to 19.93 m depth. Subsamples for stable water isotope analysis were obtained from the core at 5 cm resolution. Stable water isotope measurements were performed in autumn 2016 using cavity ring-down spectrometers L2130-i and L2140-i (Picarro Inc.) coupled to an auto-sampler (L2130-i: PAL HTC-xt, CTC Analytics AG; L2140-i: Picarro Autosampler, Picarro Inc.). The core was dated using annual layer counting of hydrogen peroxide measurements. We additionally accounted for precipitation intermittency at the drill site by using precipitation data from the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 Reanalysis extracted from the grid point closest to the firn-core drill site. The core covers the period from July 2011 to January 2016. The data has been used for investigating recent climate and environmental changes in the northern Antarctic Peninsula region providing the basis for the retrieval and analysis of a deeper ice core from the same site.