CO2 exchange between Nuuk fjord and the atmosphere Published 22.09.2011

Recently it has become clear that the CO2 content of the atmosphere plays an important role in the climate changes we are observing. Therefore knowledge about its cycle in nature has become of crucial importance in our effort to predict the extent of future climate changes. An important part of this natural cycle occurs in the barrier between sea ice and the atmosphere, where CO2 is exchanged in both directions depending on many factors. Until recently scientists believed that sea ice acted as a lid on the atmosphere, thus preventing this exchange, but a growing number of studies indicate that under certain conditions the exchange continues, and that the formation of sea ice in the winter, and its subsequent melting in the spring, depletes the CO2 levels in the surface waters, causing a significant CO2 exchange into the ocean.

A PhD project, which is a collaboration between the University of Aarhus and the Greenland Institute for Natural Resources, is expected to improve our knowledge on these CO2 exchanges. As part of initial tests, atmospherical instruments has been mounted on Qeqertat (Parallel Islands) in Nuuk fjord, where they will monitor CO2 exchanges throughout the winter. Subsequently the instruments will be moved to Zackenberg in Northeastern Greenland where scientists will measure the CO2 exchange between the atmosphere and the sea ice as it breaks up in the spring.

Photo: Jakob Sievers