Abstract
The middle Holocene was a time of definite environmental transition in the Eastern Canadian Arctic. Based on several proxy indicators (pollen, diatoms, foraminifera, molluscs and nearshore sedimentation rates), it appears that a thermal maximum occurred around middle Holocene (6-4 ka), several thousand years after the insolation maximum — a lag caused by the thermal inertia of the earlier massive ice sheet. Terrestrial records indicate that a warming began around 6 ka, both in the subarctic (Labrador - Ungava) and on Baffin Island. Marine records, on the other hand, suggested major water structure changes around 6 ka both in the Northeastern Canadian Arctic and also along the East Greenland coast with evidence of a marine surface water temperature maximum at 8 ka. We hypothesize that the marine circulation changes, both along the Baffin Island and along the East Greenland coasts, were primarily driven by glacio-isostatic uplift of the Arctic Channels. With the cessation of water flow of Atlantic (warmer) origin, and decrease in water volume from the deeper parts of the Arctic Ocean through the Arctic Channels, the export through the Fram and Denmark straits increased and the water column changed. Changes in the concentration and duration of sea ice along the eastern Canadian coast would have had important repercussions on the biota of the coastal marine and terrestrial ecosystems.
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.