Interpretation of temperature signals from ice cores : insights into the spatial and temporal variability of water isotopes in Antarctica Earths climate varies continuously across space and time but humankind has witnessed only a small snapshot of its entire history and instrumentally documented it for a mere 200 years. Our knowledge of past climate changes is therefore almost exclusively based on indirect proxy data i.e. on indicators which are sensitive to changes in climatic variables and stored in environmental archives. Extracting the data from these archives allows retrieval of the information from earlier times. Obtaining accurate proxy information is a key means to test model predictions of the past climate and only after such validation can the models be used to reliably forecast future changes in our warming world. The polar ice sheets of Greenland and Antarctica are one major climate archive which record information about local air temperatures by means of the isotopic composition of the water molecules embedded in the ice. However this temperature proxy is as any indirect climate data not a perfect recorder of past climatic variations. Apart from…