Arctic Environmental Change Recorded In Lake Sediments from Baffin Island, Canada: The Past Century Compared With the Past 200,000 Years
Abstract
Long lacustrine records are rare in glaciated parts of the Arctic, which limits our long-term perspective on current Arctic environmental change. We have recovered an unusual sedimentary record from Lake CF8 on Baffin Island, where repeated overriding advances of the Laurentide Ice Sheet accomplished very little erosion, and lake sediments from successive interglaciations are thus preserved. Here we describe environmental reconstructions based upon diatoms, chironomids, and sediment geochemistry that cover warm periods of the past ~200,000 years, i.e., the Holocene, the last interglacial (MIS 5e, ~130-120,000 years ago), and part of the penultimate interglaciation (MIS 7, which ended ~190,000 years ago). All three interglaciations were characterized by environmental changes that tracked orbital forcing. Proxy reconstructions from Lake CF8 extend to AD 2005, and record rapid warming and environmental changes over the past century which can be directly compared with changes that occurred during earlier millennia in response to natural forcing. The sedimentary record from Lake CF8 reveals that ecological changes experienced at this remote Arctic site during the past century are unprecedented over the past 200,000 years.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFMPP13F..09A
- Keywords:
-
- 1699 GLOBAL CHANGE / General or miscellaneous;
- 4902 PALEOCEANOGRAPHY / Anthropogenic effects;
- 4914 PALEOCEANOGRAPHY / Continental climate records;
- 9315 GEOGRAPHIC LOCATION / Arctic region