| Title | The behaviour of retreating glaciers controls sediment density flow activity in high-latitude fjords |
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| Author | Normandeau, A ;
Dietrich, P; Hughes Clarke, J; Van Wychen, W; Burgess, D;
Lajeunesse, P; Ghienne, J -F |
| Source | ISC2018 - 20th International Sedimentological Congress, abstract volume; 2018 p. 1 |
| Image |  |
| Year | 2018 |
| Alt Series | Natural Resources Canada, Contribution Series 20180227 |
| Publisher | IAS |
| Meeting | ISC2018 - 20th International Sedimentological Congress; Québec, QC; CA; August 13-17, 2018 |
| Document | Web site |
| Lang. | English |
| Media | paper |
| File format | pdf |
| Province | Nunavut; Northern offshore region |
| NTS | 16; 25H; 25I; 25J; 25N; 25O; 25P; 26; 27; 37E; 37G; 37H; 38A; 38B |
| Area | Baffin Island |
| Lat/Long WENS | -80.0000 -60.0000 73.0000 61.0000 |
| Subjects | hydrogeology; surficial geology/geomorphology; marine geology; sedimentology; environmental geology; Nature and Environment; fiords; glaciers; ice retreat; sediment transport; coastal environment;
sedimentary environment; nearshore environment; hydrodynamics; climate; oceanography; marine environments; deltas; sedimentary structures; drainage systems; hydrologic environment; glacial lakes; ecosystems; Climate change |
| Program | Public Safety
Geoscience Marine Geohazards |
| Released | 2018 08 01 |
| Abstract | Ice mass loss is driving important coastal morphodynamic changes in Arctic regions, from rapid coastal erosion to substantial prograding coastlines. Sediment supply delivered by rivers due to enhanced
glacial erosion/ice mass loss has dramatic consequences on nearshore sedimentary environments and associated ecosystems. However, limited data exists in Arctic coasts on the influence of ice mass loss due to climate change in modifying the nearshore
hydrodynamic of fjords. Here, we show how the behaviour of retreating glaciers and ice-mass loss influences the generation of density flows in eastern Baffin Island fjords, which has important consequences for bottom water renewal and nutrient and
carbon fluxes to the marine environment. Through a detailed analysis of sediment waves formed by sediment density flows on 31 delta fronts mapped from 2003 to 2014 and by extracting their correlative glacio-hydrological drainage basin
characteristics, we observed that the presence of glaciers controls the occurrence of density flows. However, lakes formed during glacial retreat, small or large, significantly alter the course of sediment routing to the deltas, leading to the
interruption of density flow processes in fjords. Applying these results to 700 glacio-hydrological drainage basins of eastern Baffin Island allows us to predict the location of density flows presently occurring in fjords. These findings inform local
communities and stakeholders on the locations where bottom-water renewal and organic carbon and nutrient transfer is more likely to occur, which has significant impacts on ecosystems. Our results greatly improve our understanding of modern density
flows and fjord hydrodynamic in high-latitude coasts in response to retreating glacier behaviour in a warming climate. |
| Summary | (Plain Language Summary, not published)
The examination of fjord-delta bathymetry allowed us to identify the factors that control the presence of turbidity currents in fjords. Using these
results, we predict where these turbidity currents are active for all of eastern Baffin Island, contributing to seafloor instabilities. |
| GEOSCAN ID | 311309 |
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