Research project IGV| The Late Quaternary Chronology of Arctic Ocean Sediments
Icebreaker led expeditions into the central Arctic Ocean have retrieved vast numbers of marine sediment cores that record environmental changes on millennial and orbital timescales. A major obstacle to interpreting these records is to establish accurate age models, a unique challenge in the Arctic where many traditional dating methods do not appear to work.
This proposal is designed to tackle this long-standing problem in Arctic paleoceanography by using a novel combination of chronostratigraphic methods on sediment cores recovered from key regions of the Arctic Ocean.
Project description
This study will advance our ability to determine the age of Arctic Ocean sediments, an effort needed to integrate Arctic paleoceanography with other global paleoclimate data. The Arctic is a critical and sensitive component of the global climate system.
Many climate models predict that the Arctic may be ice free in summers by the end of this century. At the other extreme, geological evidence suggests that immense land-anchored ice shelves covered the Arctic at the peak of some past glacial periods. These observations highlight an immense scale of variability in the Arctic system, yet the regularity of these swings on geological time scales is highly uncertain. This is because we struggle to date Arctic marine sediments needed to create time series from increasingly sophisticated environmental proxies. Using an extensive collection of Arctic marine sediment cores stored at Stockholm University, the project will target sediments deposited during the last 250,000 years. It will apply absolute (Radiocarbon and Optically Stimulated Luminescence) and relative (Amino Acid Racemization) dating methods, and integrate these with more traditional studies on bio-, litho- and magneto-stratigraphy. The results will improve our ability to reconstruct changes in the Arctic marine cryosphere during the recent geologic past. Ultimately this can help determine our position in the natural cycle of Earth’s climatic swings and evaluate the consequences and causes of modern changes.
Project members
Project managers
Matthew O'Regan
Professor of Marine geology
Members
Helena Alexanderson
Professor
Darrell Kaufman
Regents' Professor
Matthew O'Regan
Professor of Marine geology