Isotopes are, simply put, atoms with a specific composition. The isotopic composition of water molecules varies, for instance due to temperature, and in this way the isotopes contain an "image" of the climate at a given point in time.

The use of ice core records as climate archives thus mainly relies on the assumption that the state of the climate determines the isotopic composition of precipitation, which is "stored" in ice, and can later be analyzed in ice cores.

The ERC Starting Grant project SNOWISO (Signals from the Surface Snow: Post-Depositional Processes Controlling the Ice Core Isotopic Fingerprint) questions this view, with the hypothesis that the isotope record from an ice core is determined by a combination of the precipitation isotope signal and the atmospheric water vapor isotope signal above the snow surface.

Placed at the Geophysical Institute, Faculty of Mathematics and Natural Sciences, the project lasts from 2018-2022.