scholarly journals Holocene sea-ice dynamics in Petermann Fjord in relation to ice tongue stability and Nares Strait ice arch formation

2021 ◽  
Vol 15 (9) ◽  
pp. 4357-4380
Author(s):  
Henrieka Detlef ◽  
Brendan Reilly ◽  
Anne Jennings ◽  
Mads Mørk Jensen ◽  
Matt O'Regan ◽  
...  
Keyword(s):  
Sea Ice ◽  
Carbon Isotopic Composition ◽  
Transitional Period ◽  
Rapid Expansion ◽  
Ice Dynamics ◽  
The Holocene ◽  
Nares Strait ◽  
Sea Ice Dynamics ◽  
Short Period ◽  
Landfast Ice

Abstract. The Petermann 2015 expedition to Petermann Fjord and adjacent Hall Basin recovered a transect of cores, extending from Nares Strait to underneath the 48 km long ice tongue of Petermann glacier, offering a unique opportunity to study ice–ocean–sea ice interactions at the interface of these realms. First results suggest that no ice tongue existed in Petermann Fjord for large parts of the Holocene, raising the question of the role of the ocean and the marine cryosphere in the collapse and re-establishment of the ice tongue. Here we use a multi-proxy approach (sea-ice-related biomarkers, total organic carbon and its carbon isotopic composition, and benthic and planktonic foraminiferal abundances) to explore Holocene sea ice dynamics at OD1507-03TC-41GC-03PC in outer Petermann Fjord. Our results are in line with a tight coupling of the marine and terrestrial cryosphere in this region and, in connection with other regional sea ice reconstructions, give insights into the Holocene evolution of ice arches and associated landfast ice in Nares Strait. The late stages of the regional Holocene Thermal Maximum (6900–5500 cal yr BP) were marked by reduced seasonal sea ice concentrations in Nares Strait and the lack of ice arch formation. This was followed by a transitional period towards Neoglacial cooling from 5500–3500 cal yr BP, where a southern ice arch might have formed, but an early seasonal breakup and late formation likely caused a prolonged open water season and enhanced pelagic productivity in Nares Strait. Between 3500 and 1400 cal yr BP, regional records suggest the formation of a stable northern ice arch only, with a short period from 2500–2100 cal yr BP where a southern ice arch might have formed intermittently in response to atmospheric cooling spikes. A stable southern ice arch, or even double arching, is also inferred for the period after 1400 cal yr BP. Thus, both the inception of a small Petermann ice tongue at ∼ 2200 cal yr BP and its rapid expansion at ∼ 600 cal yr BP are preceded by a transition towards a southern ice arch regime with landfast ice formation in Nares Strait, suggesting a stabilizing effect of landfast sea ice on Petermann Glacier.

scholarly journals Holocene sea-ice dynamics in Petermann Fjord

2021 ◽  
Author(s):  
Henrieka Detlef ◽  
Brendan Reilly ◽  
Anne Jennings ◽  
Mads Mørk Jensen ◽  
Matt O'Regan ◽  
...  
Keyword(s):  
Sea Ice ◽  
Carbon Isotopic Composition ◽  
Transitional Period ◽  
Rapid Expansion ◽  
Ice Dynamics ◽  
The Holocene ◽  
Nares Strait ◽  
Sea Ice Dynamics ◽  
Short Period ◽  
Landfast Ice

Abstract. The Petermann 2015 Expedition to Petermann Fjord and adjacent Hall Basin recovered a transect of cores from Nares Strait to under the 48 km long ice tongue of Petermann glacier, offering a unique opportunity to study ice-ocean-sea ice interactions at the interface of these realms. First results suggest that no ice tongue existed in Petermann Fjord for large parts of the Holocene, raising the question of the role of the ocean and the marine cryosphere in the collapse and re-establishment of the ice tongue. Here we use a multi-proxy approach (sea-ice related biomarkers, total organic carbon and its carbon isotopic composition, and benthic and planktonic foraminiferal abundances) to explore Holocene sea-ice dynamics at OD1507-03TC-41GC-03PC in outer Petermann Fjord. Our results are in line with a tight coupling of the marine and terrestrial cryosphere in this region and, in connection with other regional sea-ice reconstructions, give insights into the Holocene evolution of ice arches and associated landfast ice in Nares Strait. The late stages of the regional Holocene Thermal Maximum (5,500–6,900 cal yrs BP) were marked by reduced seasonal sea-ice concentrations in Nares Strait and the lack of ice arch formation. This was followed by a transitional period towards neoglacial cooling from 3,500–5,500 cal yrs BP, where a southern ice arch might have formed, but an early seasonal break-up and late formation likely caused a prolonged open water season and enhanced pelagic productivity in Nares Strait. Between 1,400 cal yrs BP and 3,500 cal yrs BP, regional records suggest the formation of a stable northern ice arch only, with a short period from 2,100–2,500 cal yrs BP where a southern ice arch might have persisted in response to atmospheric cooling spikes. A stable southern ice arch, or even double arching, is also inferred for the period after 1,400 cal yrs BP. Thus, both the inception of a small Petermann ice tongue at ~2,200 cal yrs BP and its rapid expansion at ~600 cal yrs BP are preceded by a transition towards a southern ice arch regime with landfast ice formation in Nares Strait, suggesting a stabilizing effect of landfast sea ice on Petermann Glacier.

Holocene sea-ice dynamics in Petermann Fjord 

2021 ◽  
Author(s):  
Henrieka Detlef ◽  
Brendan Reilly ◽  
Anne Jennings ◽  
Mads Mørk jensen ◽  
Matt O'Regan ◽  
...  
Keyword(s):  
Sea Ice ◽  
Carbon Isotopic Composition ◽  
Greenland Ice Sheet ◽  
Ekman Transport ◽  
Tight Coupling ◽  
Ice Dynamics ◽  
The Holocene ◽  
Nares Strait ◽  
Sea Ice Dynamics ◽  
Landfast Ice

<p>Today Nares Strait is covered by sea ice for 11 months per year. The seasonal sea-ice regime and formation of landfast ice depend on the development of ice arches. Historically a northern and southern ice arch have been observed in Robeson Channel and Smith Sound, respectively, with only the southern arch leading to a complete freeze up of the strait. In recent decades, the northern arch has become more prominent, indicating a regime shift in Nares Strait sea-ice dynamics with important consequences for the export of ice from the Lincoln Sea, the regional oceanography, and the ecosystem related to the annual opening of the North Water Polynya lee of the southern ice arch. Modelling studies suggest a link between mobile sea ice and enhanced Ekman transport of modified Atlantic Water to Greenland fjord systems bordering Nares Strait. Further, a reduction in the fjords’ fast ice season, in response to Nares Strait sea-ice dynamics, might decrease its buttressing effect on the marine-terminating outlet glaciers in northern Greenland. One such glacier is Petermann Glacier, draining 4% of the Greenland Ice Sheet and terminating in a 48 km long ice tongue in Petermann Fjord.</p><p>The Petermann 2015 Expedition to Petermann Fjord and adjacent Hall Basin recovered a transect of cores from Nares Strait to under the 48 km long ice tongue of Petermann glacier. First results suggest that no ice tongue existed in Petermann Fjord for large parts of the Holocene, raising the question of the role of the ocean and the marine cryosphere in the collapse and re-establishment of the ice tongue. We present a multi-proxy study (sea-ice related biomarkers, total organic carbon and its carbon isotopic composition, and benthic and planktonic foraminiferal abundances) exploring the Holocene sea-ice dynamics at site OD1507-03TC-41GC-03PC in outer Petermann Fjord. Our results are in line with a tight coupling of the marine and terrestrial cryosphere in this region and, in connection with other regional sea-ice reconstructions, give insights into the Holocene evolution of ice arches and associated landfast ice in Nares Strait.</p>

scholarly journals Local and regional controls on Holocene sea ice dynamics and oceanography in Nares Strait, Northwest Greenland

2020 ◽  
Vol 422 ◽  
pp. 106115 ◽  
Author(s):  
Eleanor Georgiadis ◽  
Jacques Giraudeau ◽  
Anne Jennings ◽  
Audrey Limoges ◽  
Rebecca Jackson ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Dynamics ◽  
Nares Strait ◽  
Sea Ice Dynamics

scholarly journals What historical landfast ice observations tell us about projected ice conditions in Arctic Archipelagoes and marginal seas under anthropogenic forcing

2018 ◽  
Author(s):  
Frédéric Laliberté ◽  
Stephen E. L. Howell ◽  
Jean-François Lemieux ◽  
Frédéric Dupont ◽  
Ji Lei
Keyword(s):  
Sea Ice ◽  
Climate Models ◽  
Coupled Models ◽  
Ice Dynamics ◽  
Sea Ice Thickness ◽  
Anthropogenic Forcing ◽  
Marginal Seas ◽  
Sea Ice Dynamics ◽  
Landfast Ice ◽  
Ice Conditions

Abstract. Arctic landfast ice extent and duration from observations, ice assimilations, ocean re-analyses and coupled models are examined. From observations and assimilations, it is shown that in areas where landfast ice conditions last more than 5 months the first-year ice grows typically to more than 2 m and is rarely less than 1 m. The observed spatial distribution of landfast ice closely matches assimilation products but less so for ocean re-analyses and coupled models. Although models generally struggle to represent the landfast ice necessary to emulate the observed sea ice dynamics in regions favourable to landfast ice conditions, some do exhibit both a realistic climatology and a realistic decline of landfast ice extent under an anthropogenic forcing scenario. In these more realistic simulations, projections show that an extensive landfast ice cover should remain for at least 5 months of the year well until the end of the 21st century. This is in stark contrast with the simulations that have an unrealistic emulation of landfast ice conditions. In these simulations, slow and packed ice conditions shrink markedly over the same period. In all simulations and in areas with landast ice that last more than 5 months, the end-of-winter sea ice thickness remains between 1 m and 2 m well beyond the second half of the century. It is concluded that in the current generation of climate models, projections of winter sea ice conditions in the Canadian Arctic Archipelago and the Laptev Sea are overly sensitive to the representation of landfast ice conditions and that ongoing development in landfast ice parametrization will likely better constrain these projections.

scholarly journals Results from the implementation of the elastic viscous plastic sea ice rheology in HadCM3

2006 ◽  
Vol 3 (4) ◽  
pp. 777-803
Author(s):  
W. Connolley ◽  
A. Keen ◽  
A. McLaren
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Climate Model ◽  
Ice Dynamics ◽  
Sea Ice Dynamics ◽  
Future Improvement ◽  
Physically Based ◽  
Solid Foundation ◽  
Hadley Centre ◽  
Better Than

Abstract. We present results of an implementation of the Elastic Viscous Plastic (EVP) sea ice dynamics scheme into the Hadley Centre coupled ocean-atmosphere climate model HadCM3. Although the large-scale simulation of sea ice in HadCM3 is quite good with this model, the lack of a full dynamical model leads to errors in the detailed representation of sea ice and limits our confidence in its future predictions. We find that introducing the EVP scheme results in a worse initial simulation of the sea ice. This paper documents various improvements made to improve the simulation, resulting in a sea ice simulation that is better than the original HadCM3 scheme overall. Importantly, it is more physically based and provides a more solid foundation for future improvement. We then consider the interannual variability of the sea ice in the new model and demonstrate improvements over the HadCM3 simulation.

Sign in / Sign up

Export Citation Format

Share Document