Speaker: Dr. Thomas Laepple from  Alfred Wegener Institute

Title: "Understanding and interpreting the variability of water isotopes in Antarctic snow and ice-core records"

Abstract: Understanding the magnitude and causes of recent climatic trends and variability in Antarctica is hampered by the short and sparse instrumental record. Stable water isotopes in firn and ice-cores allow us to infer about past climate changes. However, the existing reconstruction efforts on the East Antarctic Plateau are too uncertain to draw quantitative conclusions about climate variability and potential anthropogenic trends. The limited skill of the existing temperature reconstructions as well as the improved understanding of the isotopic signal suggest that single firn cores or even small stacks of cores are not enough to allow a quantitative climate reconstruction.

Instead, extensive arrays of firn cores, combined with a statistical separation of signal and noise, potentially supplemented by independent temperature proxies are required. This seminar will present our ongoing work on the relationship between climate variability and isotope variability across different time-scales from field studies, forward proxy modelling and theoretical considerations and their implications for the interpretation of water isotope records.