Marine climatic framework
In association with geological sampling, it is also important to collect physical and chemical oceanographic information with a view to surveying the marine climate conditions under which present sedimentation occurs. This will form the basis for establishing a relationship between present conditions and the information, contained in sediment cores, about climatic conditions of previous ages.
The marine climate in West Greenland is today dominated by atmospheric changes and the inflow of Arctic water via the East Greenland Current and Atlantic water via the Irminger Current. Thus currents, salinity and temperature in West Greenland depend to a large extent on the ocean circulation in the North Atlantic and its variability. As the North Atlantic Oscillation (NAO) has a large influence on both the atmospheric conditions in Greenland and the ocean circulation in the North Atlantic, and thus on the intensity of the inflow of Polar and Irminger water to West Greenland waters, there is a close correlation between NAO and West Greenland’s marine climate. The observed counter-phase in air temperature between West Greenland and Northern Europe is well known today and a large part of it is believed to be related to NAO. In the course of the warming that has occurred over large parts of the northern hemisphere in the last decades, however, a smaller cooling in South Greenland and Northeast Canada has been observed; this is too pronounced to be explained by a positive NAO phase alone. Through studies of sediment cores, NAO’s phase/counter-phase through time will be examined.
Establishing a relationship between information from sediment cores and the marine climate will therefore contribute to a survey of the change in the West Greenland marine climate over time and indirectly show NAO’s variability in previous periods. This will contribute to an increased understanding of Greenland’s climate and its effects on marine ecology.
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