Spatial variability in the European winter precipitation δ18O‐NAO relationship: Implications for reconstructing NAO‐mode climate variability in the Holocene

Abstract

This paper investigates the links between precipitation δ18O and the North Atlantic Oscillation (NAO) on decadal timescales to identify the optimum locations within Europe at which to compile δ18O‐based proxy records of past NAO variability. δ18O is a commonly used paleoclimate (rainfall and temperature) proxy preserved in natural archives including stalagmites, ice cores, tree rings, and lake sediments. Precipitation δ18O data (δ18Op), compiled from Global Network of Isotopes in Precipitation (GNIP) stations in the North Atlantic sector reveal the direction and strength of the δ18Op‐NAO relationship in mid‐latitude, high‐latitude, and Mediterranean Europe. The highly significant, positive δ18Op‐NAO relationship in central Europe is attributed to the strong control of air temperature on δ18Op in this region. The δ18Op‐NAO relationship is strongly negative at high‐latitude GNIP sites and weak at Mediterranean sites. Decadal‐scale solar irradiance variations correlate with winter δ18Op at eight mid‐latitude sites.