Polar bear's range dynamics in the Holocene

Add to your list(s) Download to your calendar using vCal

• Prof. Heikki Seppa (University of Helsinki)
• Wednesday 04 December 2024, 17:30-19:00
• Latimer Room, Clare College.

If you have a question about this talk, please contact sr632.

Polar bear (Ursus maritimus) is the apex predator of the Arctic, largely dependent on sea-ice. The predicted disappearance of the ice cover of the Arctic seas by the mid 21th century is likely to cause a dramatic decrease in the global range and population size of the polar bear To place this scenario against the backdrop of past distribution changes and their causes, we use a fossil dataset to investigate the polar bear’s past distribution dynamics during the Late-Pleistocene and the Holocene. During the last deglaciation, polar bears were present at the south-western margin of the Scandinavian Ice Sheet, surviving until the earliest Holocene. There are no Arctic polar bear findings from 8,000-6,000 years ago (8-6 ka), the Holocene’s warmest period. However, findings from 8-9 ka and 5-6 ka show that the species was able to survive this period likely in cold refugia in the East Siberian Sea, the northernmost part of Greenland and the Canadian Archipelago. A marked range expansion is observed over the last 4,000 years in tandem with cooling climate and expanding Arctic sea ice. Our results highlight a remarkable dynamism of polar bear’s distribution in response to Late Pleistocene and Holocene Arctic temperature and sea ice trends.

This talk is part of the Quaternary Discussion Group (QDG) series.

This talk is included in these lists:

• AUB_Cambridge Seminars
• Climate Science Seminars within Cambridge
• Department of Earth Sciences seminars
• Department of Geography
• Latimer Room, Clare College
• Quaternary Discussion Group (QDG)
• Type the title of a new list here
• ld636
• seminars

Note that ex-directory lists are not shown.