Investigating the past and recent δ18O-accumulation relationship seen in Greenland ice cores

Decadal means of delta O-18 and accumulation rates from 52 ice core locations in Greenland are presented. The accumulation rates are derived from annual layers determined in the delta O-18 curve. Investigation of the delta O-18-accumulation relationship across the ice divide reveals a significant Foehn effect with anticorrelation of delta O-18 and accumulation rate on the lee side of the divide in Southern Greenland, while no effect is seen in Central Greenland. Furthermore, the sensitivity of accumulation rate to changes in temperature is found to be smaller in Northern Greenland than in the central and southern parts. Four records in the data set contain sufficient recent data that the period of observed temperature rise from the 1990s and onwards can be investigated. All four records are from locations close to the ice divide in Northern Greenland and while three of them show increased temperatures, no conclusive statement can be made about the accumulation rate from these data.