scholarly journals Influence of North Pacific decadal variability on the western Canadian Arctic over the past 700 years

2017 ◽  
Vol 13 (4) ◽  
pp. 411-420 ◽  
Author(s):  
François Lapointe ◽  
Pierre Francus ◽  
Scott F. Lamoureux ◽  
Mathias Vuille ◽  
Jean-Philippe Jenny ◽  
...  
Keyword(s):  
Climate Variability ◽  
Sea Ice ◽  
North Pacific ◽  
Decadal Variability ◽  
Global Climate ◽  
Canadian Arctic ◽  
Summer Precipitation ◽  
The Arctic ◽  
Past Century ◽  
The Past

Abstract. Understanding how internal climate variability influences arctic regions is required to better forecast future global climate variations. This paper investigates an annually-laminated (varved) record from the western Canadian Arctic and finds that the varves are negatively correlated with both the instrumental Pacific Decadal Oscillation (PDO) during the past century and also with reconstructed PDO over the past 700 years, suggesting drier Arctic conditions during high-PDO phases, and vice versa. These results are in agreement with known regional teleconnections, whereby the PDO is negatively and positively correlated with summer precipitation and mean sea level pressure respectively. This pattern is also evident during the positive phase of the North Pacific Index (NPI) in autumn. Reduced sea-ice cover during summer–autumn is observed in the region during PDO− (NPI+) and is associated with low-level southerly winds that originate from the northernmost Pacific across the Bering Strait and can reach as far as the western Canadian Arctic. These climate anomalies are associated with the PDO− (NPI+) phase and are key factors in enhancing evaporation and subsequent precipitation in this region of the Arctic. Collectively, the sedimentary evidence suggests that North Pacific climate variability has been a persistent regulator of the regional climate in the western Canadian Arctic. Since projected sea-ice loss will contribute to enhanced future warming in the Arctic, future negative phases of the PDO (or NPI+) will likely act to amplify this positive feedback.

scholarly journals Influence of North Pacific Decadal Variability on the Western Canadian Arctic over the past 700 years

2016 ◽  
Author(s):  
François Lapointe ◽  
Pierre Francus ◽  
Scott F. Lamoureux ◽  
Mathias Vuille ◽  
Jean-Philippe Jenny ◽  
...  
Keyword(s):  
Sea Ice ◽  
Positive Feedback ◽  
North Pacific ◽  
Decadal Variability ◽  
Global Climate ◽  
Regional Climate ◽  
Canadian Arctic ◽  
Summer Precipitation ◽  
The Arctic ◽  
The North

Abstract. It is well established that the Arctic strongly influences global climate through positive feedback processes (Cohen et al., 2014), one of the most effective being the sea-ice – albedo feedback (Screen et al., 2010). Understanding the region’s sensitivity to both internal and external forcings is a prerequisite to better forecast future global climate variations. Here, sedimentological evidence from an annually laminated (varved) record highlights that North Pacific climate variability has been a persistent regulator of the regional climate in the western Canadian Arctic. The varved record is negatively correlated with both the instrumental and reconstructed Pacific Decadal Oscillation (PDO) (D'arrigo et al., 2001; Gedalof et al., 2001; Macdonald et al., 2005; Mantua et al., 1997) throughout most of the last 700 years, suggesting drier conditions during high PDO phases, and vice-versa. This is in agreement with known regional teleconnections whereby the PDO is negatively and positively correlated with summer precipitation and mean sea level pressure, respectively. This pattern is also seen during the positive phase of the North Pacific Index (NPI) (Trenberth et al., 1994) in autumn. A reduced sea-ice cover during summer is observed in the region during PDO- (NPI+), as has been found during winter (Screen et al., 2016). Strongest during the autumn season, low-level southerly winds extend from the northernmost Pacific across the Bering Strait and can reach as far as the Western Canadian Arctic. These climate anomalies projecting onto the PDO- (NPI+) phase are key factors in enhancing evaporation and subsequent precipitation in this region. As projected sea-ice loss will contribute to enhanced future warming in the Arctic, future negative phases of the PDO (or NPI+) will likely act as amplifiers of this positive feedback (Screen et al., 2016).

Cryosphere

2004 ◽  
Author(s):  
Kenneth M. Hinkel ◽  
Andrew W. Ellis
Keyword(s):  
Sea Ice ◽  
Snow Cover ◽  
Global Climate ◽  
Ice Sheets ◽  
Past Century ◽  
High Latitudes ◽  
Ice Shelves ◽  
The Past ◽  
Third Assessment Report ◽  
The Antarctic

The cryosphere refers to the Earth’s frozen realm. As such, it includes the 10 percent of the terrestrial surface covered by ice sheets and glaciers, an additional 14 percent characterized by permafrost and/or periglacial processes, and those regions affected by ephemeral and permanent snow cover and sea ice. Although glaciers and permafrost are confined to high latitudes or altitudes, areas seasonally affected by snow cover and sea ice occupy a large portion of Earth’s surface area and have strong spatiotemporal characteristics. Considerable scientific attention has focused on the cryosphere in the past decade. Results from 2 ×CO2 General Circulation Models (GCMs) consistently predict enhanced warming at high latitudes, especially over land (Fitzharris 1996). Since a large volume of ground and surface ice is currently within several degrees of its melting temperature, the cryospheric system is particularly vulnerable to the effects of regional warming. The Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) states that there is strong evidence of Arctic air temperature warming over land by as much as 5 °C during the past century (Anisimov et al. 2001). Further, sea-ice extent and thickness has recently decreased, permafrost has generally warmed, spring snow extent over Eurasia has been reduced, and there has been a general warming trend in the Antarctic (e.g. Serreze et al. 2000). Most climate models project a sustained warming and increase in precipitation in these regions over the twenty-first century. Projected impacts include melting of ice sheets and glaciers with consequent increase in sea level, possible collapse of the Antarctic ice shelves, substantial loss of Arctic Ocean sea ice, and thawing of permafrost terrain. Such rapid responses would likely have a substantial impact on marine and terrestrial biota, with attendant disruption of indigenous human communities and infrastructure. Further, such changes can trigger positive feedback effects that influence global climate. For example, melting of organic-rich permafrost and widespread decomposition of peatlands might enhance CO2 and CH4 efflux to the atmosphere. Cryospheric researchers are therefore involved in monitoring and documenting changes in an effort to separate the natural variability from that induced or enhanced by human activity.

Snow depth on Antarctic sea ice: a Lagrangian model-based approach 

2021 ◽  
Author(s):  
Isobel R. Lawrence ◽  
Andy Ridout ◽  
Andrew Shepherd
Keyword(s):  
Sea Ice ◽  
Snow Depth ◽  
Global Climate ◽  
Lagrangian Model ◽  
The Arctic ◽  
Balance Model ◽  
The Past ◽  
Antarctic Sea Ice ◽  
Regional Trends ◽  
The Antarctic

<p>Snow on Antarctic sea ice is an important yet poorly resolved component of the global climate system. Whilst much attention over the past few years has been dedicated to producing reanalysis-forced models of snow on sea ice in the Arctic, none currently exist for the Southern Hemisphere. Here we present a Lagrangian-framework model of snow depth on Antarctic sea ice, in which “parcels” of ice accumulate snow as they drift around the ocean according to daily ice motion vectors. Snow accumulates from two sources; (i) snowfall from ERA5 atmospheric reanalysis and (ii) snow blown off the Antarctic continent, which we estimate using the RACMO2 ice sheet mass balance model. Ice parcels lose snow via wind-redistribution into leads and through snow-ice formation. We validate our dynamic snow product against ship-based measurements from the ASPeCT data archive, and we compare our long-term climatology against estimates derived from passive microwave (AMSR-E/2) satellites. Finally, we assess regional trends in snow depth over the past four decades and investigate whether these are driven by changes in snowfall or divergence/convergence of the Antarctic sea ice pack. </p>

scholarly journals Sea Ice in the Canadian Arctic Archipelago: Modeling the Past (1950–2004) and the Future (2041–60)

2009 ◽  
Vol 22 (8) ◽  
pp. 2181-2198 ◽  
Author(s):  
Tessa Sou ◽  
Gregory Flato
Keyword(s):  
Sea Ice ◽  
Climate Models ◽  
Global Climate ◽  
Canadian Arctic ◽  
Arctic Sea Ice ◽  
Global Climate Models ◽  
Canadian Arctic Archipelago ◽  
The Past ◽  
The Future ◽  
Ice Retreat

Abstract Considering the recent losses observed in Arctic sea ice and the anticipated future warming due to anthropogenic greenhouse gas emissions, sea ice retreat in the Canadian Arctic Archipelago (CAA) is expected and indeed is already being observed. As most global climate models do not resolve the CAA region, a fine-resolution ice–ocean regional model is developed and used to make a projection of future changes in the CAA sea ice. Results from a historical run (1950–2004) are used to evaluate the model. The model does well in representing observed sea ice spatial and seasonal variability, but tends to underestimate summertime ice cover. The model results for the future (2041–60) show little change in wintertime ice concentrations from the past, but summertime ice concentrations decrease by 45%. The ice thickness is projected to decrease by 17% in the winter and by 36% in summer. Based on this study, a completely ice-free CAA is unlikely by the year 2050, but the simulated ice retreat suggests that the region could support some commercial shipping.

scholarly journals Supplementary material to "Influence of North Pacific Decadal Variability on the Western Canadian Arctic over the past 700 years"

2016 ◽  
Author(s):  
François Lapointe ◽  
Pierre Francus ◽  
Scott F. Lamoureux ◽  
Mathias Vuille ◽  
Jean-Philippe Jenny ◽  
...  
Keyword(s):  
North Pacific ◽  
Decadal Variability ◽  
Canadian Arctic ◽  
The Past ◽  
Pacific Decadal Variability ◽  
Supplementary Material

Non-steady behaviour in the Cenozoic polar North Atlantic system: the onset and variability of Northern Hemisphere glaciations

1995 ◽  
Vol 352 (1699) ◽  
pp. 373-385 ◽  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Northern Hemisphere ◽  
North Atlantic ◽  
Middle Miocene ◽  
Ice Cover ◽  
The Arctic ◽  
Past Century ◽  
The Past ◽  
The Arctic Ocean

Changes of the extent of the Arctic Ocean sea-ice cover over the past century, the geological record of the Arctic Ocean seafloor of the youngest geological past, as well as the evidence of a pre-Glacial temperate to warm Arctic Ocean during Mesozoic and Palaeogene time are witnesses of dramatic revolutions of the Arctic oceanography. The climate over northwestern Europe on a regional scale as well as the global environment have responded to these revolutions instantly over geological time scales. Results of ocean drilling in the deep northern North Atlantic document an onset of Northern Hemisphere glaciation towards the end of the middle Miocene (10-14 Ma). While the available evidence points to early glaciations of modest extent and intensity centred around southern Greenland, the early to mid-Pliocene intervals record a sudden intensification of ice-rafting in the Labrador and Norwegian Greenland seas as well as in the Arctic Ocean proper. The Greenland ice cap seems to have remained rather stable whereas the northwest European ice shields have experienced rapid and dramatic changes leading to their frequent complete destruction. Many sediment properties seem to suggest that orbital parameters (Milankovitch-frequencies) and their temporal variability control important properties of the deep-sea floor depositional environment. Obliquity (with approximately 40 ka) seems to be dominant in pre-Glacial (middle Miocene) as well as Glacial (post late Miocene) scenarios whereas eccentricity (with approximately 100 ka) only dominated the past 600-800 ka. PlioPleistocene deposits of the Arctic Ocean proper, of the entire Norwegian Greenland and of the Labrador seas have recorded the almost continuous presence of sea-ice cover with only short ‘interglacial’ intervals when the eastern Norwegian Sea was ice-free. The documentation of long-term changes of the oceanographic and climatic properties of the Arctic environments recorded in the sediment cover of the deepsea floors might also serve to explain scenarios which have no modern analog, but which might well develop in the future under the influence of the anthropogenic drift towards warmer global climates.

scholarly journals Observation-based selection of climate models projects Arctic ice-free summers around 2035

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
David Docquier ◽  
Torben Koenigk
Keyword(s):  
Model Selection ◽  
Sea Ice ◽  
Climate Models ◽  
Global Climate ◽  
Coupled Model ◽  
Arctic Sea Ice ◽  
Global Climate Models ◽  
The Arctic ◽  
Arctic Sea ◽  
Area And Volume

AbstractArctic sea ice has been retreating at an accelerating pace over the past decades. Model projections show that the Arctic Ocean could be almost ice free in summer by the middle of this century. However, the uncertainties related to these projections are relatively large. Here we use 33 global climate models from the Coupled Model Intercomparison Project 6 (CMIP6) and select models that best capture the observed Arctic sea-ice area and volume and northward ocean heat transport to refine model projections of Arctic sea ice. This model selection leads to lower Arctic sea-ice area and volume relative to the multi-model mean without model selection and summer ice-free conditions could occur as early as around 2035. These results highlight a potential underestimation of future Arctic sea-ice loss when including all CMIP6 models.

scholarly journals Societal implications of a changing Arctic Ocean

AMBIO ◽  
2021 ◽  
Author(s):  
Henry P. Huntington ◽  
Andrey Zagorsky ◽  
Bjørn P. Kaltenborn ◽  
Hyoung Chul Shin ◽  
Jackie Dawson ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Indigenous Peoples ◽  
Global Climate ◽  
Rapid Change ◽  
The Arctic ◽  
Cultural Continuity ◽  
Societal Implications ◽  
Arctic Ecosystems ◽  
The Many

AbstractThe Arctic Ocean is undergoing rapid change: sea ice is being lost, waters are warming, coastlines are eroding, species are moving into new areas, and more. This paper explores the many ways that a changing Arctic Ocean affects societies in the Arctic and around the world. In the Arctic, Indigenous Peoples are again seeing their food security threatened and cultural continuity in danger of disruption. Resource development is increasing as is interest in tourism and possibilities for trans-Arctic maritime trade, creating new opportunities and also new stresses. Beyond the Arctic, changes in sea ice affect mid-latitude weather, and Arctic economic opportunities may re-shape commodities and transportation markets. Rising interest in the Arctic is also raising geopolitical tensions about the region. What happens next depends in large part on the choices made within and beyond the Arctic concerning global climate change and industrial policies and Arctic ecosystems and cultures.

Arctocyclopina pagonasta, a new genus and species of the family Cyclopinidae (Cyclopoida, Copepoda) from the annual sea ice in the Canadian Arctic

1985 ◽  
Vol 63 (10) ◽  
pp. 2389-2394 ◽  
Author(s):  
A. A. Mohammed ◽  
Vidar Neuhof
Keyword(s):  
Sea Ice ◽  
New Genus ◽  
Canadian Arctic ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
New Genus And Species ◽  
Arctic Sea ◽  
The Family

A new genus and species of Cyclopoida is described; Arctocyclopina pagonasta is found inhabiting the arctic sea ice. Comparison is made with Cyclopina gracilis Claus, with which it may be confused.

scholarly journals Synoptic climatological approach associated with three recent summer heatwaves in the Canadian Arctic

2020 ◽  
Vol 11 (S1) ◽  
pp. 233-250 ◽  
Author(s):  
Farahnaz Fazel-Rastgar
Keyword(s):  
Sea Ice ◽  
Canadian Arctic ◽  
Arctic Region ◽  
Low Pressure ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
The North ◽  
Pressure Centre ◽  
Temperature Records ◽  
Arctic Temperature

Abstract The observed unusually high temperatures in the Arctic during recent decades can be related to the Arctic sea ice declines in summer 2007, 2012 and 2016. Arctic dipole formation has been associated with all three heatwaves of 2007, 2012 and 2016 in the Canadian Arctic. Here, the differences in weather patterns are investigated and compared with normal climatological mean (1981–2010) structures. This study examines the high-resolution datasets from the North American Regional Reanalysis model. During the study periods, the north of Alaska has been affected by the low-pressure tongue. The maximum difference between Greenland high-pressure centre and Alaska low-pressure tongue for the summers of 2012, 2016 and 2007 are 8 hPa, 7 hPa and 6 hPa, respectively, corresponding and matching to the maximum summer surface Canadian Arctic temperature records. During anomalous summer heatwaves, low-level wind, temperatures, total clouds (%) and downward radiation flux at the surface are dramatically changed. This study shows the surface albedo has been reduced over most parts of the Canadian Arctic Ocean during the mentioned heatwaves (∼5–40%), with a higher change (specifically in the eastern Canadian Arctic region) during summer 2012 in comparison with summer 2016 and summer 2007, agreeing with the maximum surface temperature and sea ice decline records.

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