Dre Estelle Allan - Meltwater, primary productivity and sea surface conditions in Baffin Bay and Labrador Sea during the Holocene

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Dre Estelle Allan, Geotop-McGill

Vendredi 5 février 2021 à 11h00 - Friday, February 5, 2021 at 11am
Lien Zoom/Zoom link: https://mcgill.zoom.us/j/86337986906?pwd=R2tnYnVyRmpxWlMxT1pYdEd6RWdnZz09
Résumé / abstract:

Climatic changes have strong consequences for surface air temperature and oceanic conditions, in particular in Arctic and subarctic regions. Carbon dioxide (CO2) released into the atmosphere by anthropogenic activities has led to a warming of atmospheric and ocean temperatures, leading to an increase in precipitation associated with a decrease in sea ice cover and rapid melting of the ice caps, the latter contributing significantly to global sea-level rise. Nonetheless, the ocean has absorbed about 30% of the emitted anthropogenic carbon since pre-industrial times (see IPCC 2019). This carbon sink is largely due to global ocean primary productivity. In Arctic and subarctic environments, oceanic primary productivity is related to hydrological conditions and ice dynamics, which contribute to nutrient inputs to the surface, thus triggering spring, summer and fall plankton blooms. Recent studies have shown that in polar and sub-polar environments, primary productivity is closely linked to freshwater inputs from runoff, melting ice caps and sea ice. Along the West Greenland coast, marine-terminating glaciers induce high primary productivity by meltwater discharge at the base of tidal glaciers contributing to vertical mixing in the water column and nutrient resuspension towards the surface. A core (SA13-ST3) from the South West Greenland shelf illustrate the amplitude of sea-surface conditions and productivity changes off South West Greenland, northern Labrador Sea, in response to the high deglacial meltwater rates occurring during the Holocene. For example, during the Middle Holocene, the retreating of the Greenland Ice Sheet led to elevated meltwater discharge along the shelf, and it is also possible that a relatively high sea level, during this time period, contributed to an enhanced primary productivity, as higher sea levels would have increase the presence of marine-terminating glaciers despite the retreating of the glaciers inland, which would have favored a deeper upwelling.

Passcode: 010917

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Meltwater, primary productivity and sea surface conditions in Baffin Bay and Labrador Sea during the Holocene

Ajouter au calendrier 2021-02-05 11:00:00 2021-05-07 15:55:43 Dre Estelle Allan - Meltwater, primary productivity and sea surface conditions in Baffin Bay and Labrador Sea during the Holocene Climatic changes have strong consequences for surface air temperature and oceanic conditions, in particular in Arctic and subarctic regions. Carbon dioxide (CO2) released into the atmosphere by anthropogenic activities has led to a warming of atmospheric and ocean temperatures, leading to an increase in precipitation associated with a decrease in sea ice cover and rapid melting of the ice caps, the latter contributing significantly to global sea-level rise. Nonetheless, the ocean has absorbed about 30% of the emitted anthropogenic carbon since pre-industrial times (see IPCC 2019). This carbon sink is largely due to global ocean primary productivity. In Arctic and subarctic environments, oceanic primary productivity is related to hydrological conditions and ice dynamics, which contribute to nutrient inputs to the surface, thus triggering spring, summer and fall plankton blooms. Recent studies have shown that in polar and sub-polar environments, primary productivity is closely linked to freshwater inputs from runoff, melting ice caps and sea ice. Along the West Greenland coast, marine-terminating glaciers induce high primary productivity by meltwater discharge at the base of tidal glaciers contributing to vertical mixing in the water column and nutrient resuspension towards the surface. A core (SA13-ST3) from the South West Greenland shelf illustrate the amplitude of sea-surface conditions and productivity changes off South West Greenland, northern Labrador Sea, in response to the high deglacial meltwater rates occurring during the Holocene. For example, during the Middle Holocene, the retreating of the Greenland Ice Sheet led to elevated meltwater discharge along the shelf, and it is also possible that a relatively high sea level, during this time period, contributed to an enhanced primary productivity, as higher sea levels would have increase the presence of marine-terminating glaciers despite the retreating of the glaciers inland, which would have favored a deeper upwelling. Passcode: 010917 Geotop admin@example.com America/New_York public