In the Eurasian Arctic, the archipelago of Severnaya Zemlya is the easternmost one which is covered by considerable ice caps. A 724 m long ice core was drilled from 1999 to 2001 on Akademii Nauk, the northernmost ice cap of Severnaya Zemlya. This project was carried out in co-operation between the Alfred Wegener Institute (AWI), Germany, the Arctic and Antarctic Research Institute (AARI) St. Petersburg and the Mining Institute St. Petersburg, Russia.The investigated ice cap is characterized by infiltration processes.This paper presents a preliminary dating of the ice core mostly based on studies of isotopic composition and electric conductivity. Pollution of anthropogenic origin (accident of Chernobyl nuclear power plant in 1986, nuclear bomb tests in the atmosphere at the beginning of the 1960s), are other well defined time markers which were used for dating.Using a combination of Oxygen-18 and Deuterium excess data with high resolution and horizons of high electric conductivity measured by dielectric profiling (DEP) we could determine a time scale for the top 350 m reaching back to 1100 AD. A multiproxy approach indicates a basal age of the ice cap of approximately 2500 years.Our results suggest that this ice cap is not in equilibrium but has grown until modern times. We re-constructed a relative temperature trend for the last 2500 years. A detailed interpretation of climate changes is given.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > POL6-Earth climate variability since the Pliocene