How does sea ice influence δ18O of Arctic precipitation?

This study investigates how variations in Arctic sea ice cover influence δ¹⁸O of present day Arctic precipitation. This is done using the model isoCAM3, an isotope-equipped version of the National Center for Atmospheric Research Community Atmosphere Model version. Four sensitivity experiments and one control simulation are performed with prescribed SST and sea ice. Each of the four experiments simulates the atmospheric and isotopic response to Arctic oceanic conditions for selected years after the beginning of the satellite era in 1979. Results show that δ¹⁸O of precipitation is sensitive to local changes of sea ice concentration. Reduced sea ice extent yields more enriched isotope values while increased sea ice extent yields more depleted isotope values. The distribution of the sea ice cover is essential for the spatial distribution of the simulated changes in δ¹⁸O. The experiments of this study show no changes of δ¹⁸O for central Greenland. However, this does not exclude that simulations based on other sea ice distributions might yield changes in Greenland δ¹⁸O. [ABSTRACT FROM AUTHOR]