Influence of Arctic sea-ice loss on the Greenland ice sheet climate

AbstractThe Arctic is the region on Earth that is warming the fastest. At the same time, Arctic sea ice is reducing while the Greenland ice sheet (GrIS) is losing mass at an accelerated pace. Here, we study the seasonal impact of reduced Arctic sea ice on GrIS surface mass balance (SMB), using the Community Earth System Model version 2.1 (CESM2), which features an advanced, interactive calculation of SMB. Addressing the impact of sea-ice reductions on the GrIS SMB from observations is difficult due to the short observational records. Also, signals detected using transient climate simulations may be aliases of other forcings. Here, we analyze dedicated simulations from the Polar Amplification Model Intercomparison Project with reduced Arctic sea ice and compare them with preindustrial sea ice simulations while keeping all other forcings constant. In response to reduced sea ice, the GrIS SMB increases in winter due to increased precipitation, driven by the more humid atmosphere and increasing cyclones. In summer, surface melt increases due to a warmer, more humid atmosphere providing increased energy transfer to the surface through the sensible and latent heat fluxes, which triggers the melt-albedo feedback. Further, warming occurs throughout the entire troposphere over Baffin Bay. This deep warming results in regional enhancement of the 500 hPa geopotential heights over the Baffin Bay and Greenland, increasing blocking and heat advection over the GrIS’ surface. This anomalous circulation pattern has been linked to recent increases in the surface melt of the GrIS.

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Investigating the Local Scale Influence of Sea Ice on Greenland Surface Melt

10.5194/tc-2017-65 ◽

2017 ◽

Cited By ~ 1

Author(s):

Julienne C. Stroeve ◽

John R. Mioduszewski ◽

Asa Rennermalm ◽

Linette N. Boisvert ◽

Marco Tedesco ◽

...

Keyword(s):

Sea Ice ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Rapid Decline ◽

Baffin Bay ◽

Sheet Surface ◽

Surface Melt

Abstract. Rapid decline in Arctic sea ice cover in the 21st century may have wide-reaching effects on the Arctic climate system, including the Greenland ice sheet mass balance. Here, we investigate whether local changes in sea ice around the Greenland ice sheet have had an impact on Greenland surface melt. Specifically, we investigate the relationship between sea ice concentration, the timing of melt onset and open water fraction surrounding Greenland with ice sheet surface melt using a combination of remote sensing observations, and outputs from a reanalysis model and a regional climate model for the period 1979–2015. Statistical analysis points to covariability between Greenland ice sheet surface melt and sea ice within Baffin Bay and Davis Strait. While some of this covariance can be explained by simultaneous influence of atmospheric circulation anomalies on both the sea ice cover and Greenland melt, within Baffin Bay we find a modest correlation between detrended melt onset over sea ice and the adjacent ice sheet melt onset. This correlation appears to be related to increased transfer of sensible and latent heat fluxes from the ocean to the atmosphere in early sea ice melt years, increasing temperatures and humidity over the ice sheet that in turn initiate ice sheet melt.

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Investigating the local-scale influence of sea ice on Greenland surface melt

The Cryosphere ◽

10.5194/tc-11-2363-2017 ◽

2017 ◽

Vol 11 (5) ◽

pp. 2363-2381 ◽

Cited By ~ 13

Author(s):

Julienne C. Stroeve ◽

John R. Mioduszewski ◽

Asa Rennermalm ◽

Linette N. Boisvert ◽

Marco Tedesco ◽

...

Keyword(s):

Sea Ice ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Rapid Decline ◽

Baffin Bay ◽

Sheet Surface ◽

Surface Melt

Abstract. Rapid decline in Arctic sea ice cover in the 21st century may have wide-reaching effects on the Arctic climate system, including the Greenland ice sheet mass balance. Here, we investigate whether local changes in sea ice around the Greenland ice sheet have had an impact on Greenland surface melt. Specifically, we investigate the relationship between sea ice concentration, the timing of melt onset and open-water fraction surrounding Greenland with ice sheet surface melt using a combination of remote sensing observations, and outputs from a reanalysis model and a regional climate model for the period of 1979–2015. Statistical analysis points to covariability between Greenland ice sheet surface melt and sea ice within Baffin Bay and Davis Strait. While some of this covariance can be explained by simultaneous influence of atmospheric circulation anomalies on both the sea ice cover and Greenland melt, within Baffin Bay we find a modest correlation between detrended melt onset over sea ice and the adjacent ice sheet melt onset. This correlation appears to be related to increased transfer of sensible and latent heat fluxes from the ocean to the atmosphere in early sea ice melt years, increasing temperatures and humidity over the ice sheet that in turn initiate ice sheet melt.

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Has Arctic Sea Ice Loss Contributed to Increased Surface Melting of the Greenland Ice Sheet?

Journal of Climate ◽

10.1175/jcli-d-15-0391.1 ◽

2016 ◽

Vol 29 (9) ◽

pp. 3373-3386 ◽

Cited By ~ 23

Author(s):

Jiping Liu ◽

Zhiqiang Chen ◽

Jennifer Francis ◽

Mirong Song ◽

Thomas Mote ◽

...

Keyword(s):

Sea Ice ◽

Thermohaline Circulation ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Atmospheric Model ◽

Surface Melting ◽

Arctic Sea Ice ◽

The Arctic ◽

Arctic Sea ◽

Ice Conditions

Abstract In recent decades, the Greenland ice sheet has experienced increased surface melt. However, the underlying cause of this increased surface melting and how it relates to cryospheric changes across the Arctic remain unclear. Here it is shown that an important contributing factor is the decreasing Arctic sea ice. Reduced summer sea ice favors stronger and more frequent occurrences of blocking-high pressure events over Greenland. Blocking highs enhance the transport of warm, moist air over Greenland, which increases downwelling infrared radiation, contributes to increased extreme heat events, and accounts for the majority of the observed warming trends. These findings are supported by analyses of observations and reanalysis data, as well as by independent atmospheric model simulations using a state-of-the-art atmospheric model that is forced by varying only the sea ice conditions. Reduced sea ice conditions in the model favor more extensive Greenland surface melting. The authors find a positive feedback between the variability in the extent of summer Arctic sea ice and melt area of the summer Greenland ice sheet, which affects the Greenland ice sheet mass balance. This linkage may improve the projections of changes in the global sea level and thermohaline circulation.

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Holocene variability in sea ice and primary productivity in the northeastern Baffin Bay

arktos ◽

10.1007/s41063-020-00075-y ◽

2020 ◽

Vol 6 (1-3) ◽

pp. 55-73 ◽

Cited By ~ 3

Author(s):

Jeetendra Saini ◽

Ruediger Stein ◽

Kirsten Fahl ◽

Jens Weiser ◽

Dierk Hebbeln ◽

...

Keyword(s):

Sea Ice ◽

Ocean Circulation ◽

Water Discharge ◽

Greenland Ice Sheet ◽

Open Water ◽

Ice Cover ◽

Arctic Sea Ice ◽

Baffin Bay ◽

Arctic Sea ◽

Ice Edge

AbstractArctic sea ice is a critical component of the climate system, known to influence ocean circulation, earth’s albedo, and ocean–atmosphere heat and gas exchange. Current developments in the use of IP25 (a sea ice proxy with 25 carbon atoms only synthesized by Arctic sea ice diatoms) have proven it to be a suitable proxy for paleo-sea ice reconstructions over hundreds of thousands to even millions of years. In the NE Baffin Bay, off NW Greenland, Melville Bugt is a climate-sensitive region characterized by strong seasonal sea ice variability and strong melt-water discharge from the Greenland Ice Sheet (GIS). Here, we present a centennial-scale resolution Holocene sea ice record, based on IP25 and open-water phytoplankton biomarkers (brassicasterol, dinosterol and HBI III) using core GeoB19927-3 (73° 35.26′ N, 58° 05.66′ W). Seasonal to ice-edge conditions near the core site are documented for most of the Holocene period with some significant variability. In the lower-most part, a cold interval characterized by extensive sea ice cover and very low local productivity is succeeded by an interval (~ 9.4–8.5 ka BP) with reduced sea ice cover, enhanced GIS spring melting, and strong influence of the West Greenland Current (WGC). From ~ 8.5 until ~ 7.8 ka BP, a cooling event is recorded by ice algae and phytoplankton biomarkers. They indicate an extended sea ice cover, possibly related to the opening of Nares Strait, which may have led to an increased influx of Polar Water into NE-Baffin Bay. The interval between ~ 7.8 and ~ 3.0 ka BP is characterized by generally reduced sea ice cover with millennial-scale variability of the (late winter/early spring) ice-edge limit, increased open-water conditions (polynya type), and a dominant WGC carrying warm waters at least as far as the Melville Bugt area. During the last ~ 3.0 ka BP, our biomarker records do not reflect the late Holocene ‘Neoglacial cooling’ observed elsewhere in the Northern Hemisphere, possibly due to the persistent influence of the WGC and interactions with the adjacent fjords. Peaks in HBI III at about ~ 2.1 and ~ 1.3 ka BP, interpreted as persistent ice-edge situations, might correlate with the Roman Warm Period (RWP) and Medieval Climate Anomaly (MCA), respectively, in-phase with the North Atlantic Oscillation (NAO) mode. When integrated with marine and terrestrial records from other circum-Baffin Bay areas (Disko Bay, the Canadian Arctic, the Labrador Sea), the Melville Bugt biomarker records point to close ties with high Arctic and Northern Hemispheric climate conditions, driven by solar and oceanic circulation forcings.

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The Impact of Regional Arctic Sea Ice Loss on Atmospheric Circulation and the NAO

Journal of Climate ◽

10.1175/jcli-d-15-0315.1 ◽

2016 ◽

Vol 29 (2) ◽

pp. 889-902 ◽

Cited By ~ 51

Author(s):

Rasmus A. Pedersen ◽

Ivana Cvijanovic ◽

Peter L. Langen ◽

Bo M. Vinther

Keyword(s):

Sea Ice ◽

Atmospheric Circulation ◽

General Circulation ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Near Surface ◽

Arctic Sea ◽

The Impact ◽

Sea Ice Reduction

Abstract Reduction of the Arctic sea ice cover can affect the atmospheric circulation and thus impact the climate beyond the Arctic. The atmospheric response may, however, vary with the geographical location of sea ice loss. The atmospheric sensitivity to the location of sea ice loss is studied using a general circulation model in a configuration that allows combination of a prescribed sea ice cover and an active mixed layer ocean. This hybrid setup makes it possible to simulate the isolated impact of sea ice loss and provides a more complete response compared to experiments with fixed sea surface temperatures. Three investigated sea ice scenarios with ice loss in different regions all exhibit substantial near-surface warming, which peaks over the area of ice loss. The maximum warming is found during winter, delayed compared to the maximum sea ice reduction. The wintertime response of the midlatitude atmospheric circulation shows a nonuniform sensitivity to the location of sea ice reduction. While all three scenarios exhibit decreased zonal winds related to high-latitude geopotential height increases, the magnitudes and locations of the anomalies vary between the simulations. Investigation of the North Atlantic Oscillation reveals a high sensitivity to the location of the ice loss. The northern center of action exhibits clear shifts in response to the different sea ice reductions. Sea ice loss in the Atlantic and Pacific sectors of the Arctic cause westward and eastward shifts, respectively.

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Natural variability of the Arctic Ocean sea ice during the present interglacial

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2008996117 ◽

2020 ◽

Vol 117 (42) ◽

pp. 26069-26075

Author(s):

Anne de Vernal ◽

Claude Hillaire-Marcel ◽

Cynthia Le Duc ◽

Philippe Roberge ◽

Camille Brice ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Natural Variability ◽

Arctic Sea Ice ◽

The Arctic ◽

Lomonosov Ridge ◽

Arctic Sea ◽

The Arctic Ocean ◽

Open Question ◽

The Impact

The impact of the ongoing anthropogenic warming on the Arctic Ocean sea ice is ascertained and closely monitored. However, its long-term fate remains an open question as its natural variability on centennial to millennial timescales is not well documented. Here, we use marine sedimentary records to reconstruct Arctic sea-ice fluctuations. Cores collected along the Lomonosov Ridge that extends across the Arctic Ocean from northern Greenland to the Laptev Sea were radiocarbon dated and analyzed for their micropaleontological and palynological contents, both bearing information on the past sea-ice cover. Results demonstrate that multiyear pack ice remained a robust feature of the western and central Lomonosov Ridge and that perennial sea ice remained present throughout the present interglacial, even during the climate optimum of the middle Holocene that globally peaked ∼6,500 y ago. In contradistinction, the southeastern Lomonosov Ridge area experienced seasonally sea-ice-free conditions, at least, sporadically, until about 4,000 y ago. They were marked by relatively high phytoplanktonic productivity and organic carbon fluxes at the seafloor resulting in low biogenic carbonate preservation. These results point to contrasted west–east surface ocean conditions in the Arctic Ocean, not unlike those of the Arctic dipole linked to the recent loss of Arctic sea ice. Hence, our data suggest that seasonally ice-free conditions in the southeastern Arctic Ocean with a dominant Arctic dipolar pattern, may be a recurrent feature under “warm world” climate.

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Arctic ice in cross-disciplinary undergraduate education: Experiences across natural science, social science, international policy, and public writing

10.5194/egusphere-egu2020-12600 ◽

2020 ◽

Author(s):

Michelle Koutnik ◽

Nadine Fabbi ◽

Elizabeth Wessells ◽

Ellen Ahlness ◽

Max Showalter ◽

...

Keyword(s):

Sea Ice ◽

Undergraduate Education ◽

Greenland Ice Sheet ◽

Arctic Sea Ice ◽

The Arctic ◽

International Policy ◽

Public Writing ◽

Arctic Sea ◽

Arctic Ice ◽

The University

With the Arctic currently warming at a rate at least twice that of the global average, the coupled Arctic ecosystem is losing ice. This includes significant land-ice loss from the Greenland Ice Sheet and Arctic ice caps and glaciers, reduction in extent and thickness of Arctic sea ice, and thawing permafrost. This scale of environmental change significantly affects Arctic people, wildlife, infrastructure, transportation, and access. Societal response to these changes relies on advances in and application of research spanning multiple scientific disciplines, with policy-making done in partnership with Indigenous people, governments, private agencies, multinational corporations, and other interested groups. Everyone will interface with outcomes due to a changing climate and the challenge is mounting for the next generation of leaders. The cross-disciplinary nature of the challenge of Arctic ice loss and climate change must be met by cross-disciplinary undergraduate education. While higher education aims for disciplinary training in natural sciences and social sciences, there is an increasing responsibility to integrate topics and immerse students in real-world issues. And, in our experience the undergraduates we teach are eager for courses that can do this well.What is immersive undergraduate education? We consider this as either immersing students in a focused topic in the classroom, immersing students in a place (especially while abroad), or combining the two through targeted lectures, informed discussions, travel, and writing. With regard to the Arctic, it is necessary to bring scientific understanding to learning activities otherwise focused on societal impacts, policy making, and knowledge exchange through public writing.We share from our practical experience teaching Arctic-focused courses to classes each with 10-30 students with majors from across the University of Washington (UW) campus (total undergraduate student body of 32,000). Three recent activities that integrate the state of science with impacts on society in undergraduate courses include: 1) a four-week study abroad course to Greenland and Denmark focusing on changes in the Greenland Ice Sheet and sea-level rise, 2) a 10-week Task Force course in Arctic Sea Ice and International Policy in partnership with the UW International Policy Institute at the Henry M. Jackson School of International Studies that includes one-week in Ottawa where students develop a mock Arctic sea ice policy for Canada consistent with Inuit priorities, and 3) a 10-week seminar in public writing where students write mock newspaper articles, book reviews, and policy summaries about ice in a changing climate. These courses were designed to include a similar subset of earth science, atmospheric science, and oceanography, but the distinct structure and application of the science in these three separate courses led to distinct learning outcomes. In addition, we present how the academic minor in Arctic Studies at the University of Washington has allowed students to design their own integrated understanding of Indigenous and nation-state Arctic geopolitics, Arctic environmental change, and policy by taking a selection of courses and engaging in research and report writing.

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Interannual variability in Transpolar Drift ice thickness and potential impact of Atlantification

10.5194/tc-2020-305 ◽

2020 ◽

Author(s):

H. Jakob Belter ◽

Thomas Krumpen ◽

Luisa von Albedyll ◽

Tatiana A. Alekseeva ◽

Sergei V. Frolov ◽

...

Keyword(s):

Time Series ◽

Sea Ice ◽

Arctic Sea Ice ◽

The Arctic ◽

Ice Thickness ◽

Fram Strait ◽

Ice Growth ◽

Arctic Sea ◽

Transpolar Drift ◽

The Impact

Abstract. Changes in Arctic sea ice thickness are the result of complex interactions of the dynamic and variable ice cover with atmosphere and ocean. Most of the sea ice exits the Arctic Ocean through Fram Strait, which is why long-term measurements of ice thickness at the end of the Transpolar Drift provide insight into the integrated signals of thermodynamic and dynamic influences along the pathways of Arctic sea ice. We present an updated time series of extensive ice thickness surveys carried out at the end of the Transpolar Drift between 2001 and 2020. Overall, we see a more than 20 % thinning of modal ice thickness since 2001. A comparison with first preliminary results from the international Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) shows that the modal summer thickness of the MOSAiC floe and its wider vicinity are consistent with measurements from previous years. By combining this unique time series with the Lagrangian sea ice tracking tool, ICETrack, and a simple thermodynamic sea ice growth model, we link the observed interannual ice thickness variability north of Fram Strait to increased drift speeds along the Transpolar Drift and the consequential variations in sea ice age and number of freezing degree days. We also show that the increased influence of upward-directed ocean heat flux in the eastern marginal ice zones, termed Atlantification, is not only responsible for sea ice thinning in and around the Laptev Sea, but also that the induced thickness anomalies persist beyond the Russian shelves and are potentially still measurable at the end of the Transpolar Drift after more than a year. With a tendency towards an even faster Transpolar Drift, winter sea ice growth will have less time to compensate the impact of Atlantification on sea ice growth in the eastern marginal ice zone, which will increasingly be felt in other parts of the sea ice covered Arctic.

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Sea ice kinematic features in the Arctic outflow region and their associations with Arctic Northeast Passage accessibility

Abstracts of the ICA ◽

10.5194/ica-abs-1-101-2019 ◽

2019 ◽

Vol 1 ◽

pp. 1-1

Author(s):

Dawei Gui ◽

Xiaoping Pang ◽

Ruibo Lei ◽

Xi Zhao ◽

Jia Wang

Keyword(s):

Sea Ice ◽

Arctic Sea Ice ◽

The Arctic ◽

Fram Strait ◽

The North ◽

Atmospheric Circulation Indices ◽

Arctic Sea ◽

Outflow Region ◽

Transpolar Drift ◽

The Impact

Abstract. Increasing amounts of evidence have proven Arctic sea ice is undergoing remarkable loss. On the bright side, the Arctic sea routes are becoming increasingly accessible. In this study, the NSIDC product of sea ice motion was applied to reconstruct the northward speed of sea ice to obtain the kinematic features of the sea ice in the Arctic outflow region which specially referred to the Fram Strait and to the north of the Northeast Passage (NEP).In the Arctic outflow region, the average southward displacement of sea ice in 2007&ndash;2014 (1511&thinsp;km) was more than twice the average prior to 2007 (617&thinsp;km), which indicated continuous enhancement of the Transpolar Drift Stream (TDS) in comparison with previous years. In the regions to the north of the NEP, the long-term trend of northward sea ice speed in the Kara sector was +0.04&thinsp;cm&thinsp;s&minus;1&thinsp;year&minus;1 in spring. A significant statistical relationship was found between the NEP open period and the northward speed of the sea ice to the north of the NEP. The offshore advection of sea ice could account for the opening of sea routes by 33% and 15% in the Kara and Laptev sectors, respectively.The atmospheric circulation indices across the TDS, i.e., the Central Arctic Index (CAI), presented more significant correlation than for the Arctic atmospheric Dipole Anomaly index with the open period of the NEP, and the CAI could explain the southward displacement of sea ice toward Fram Strait by more than 45%. The impact from the summer positive CAI reinforces the thinning and mechanical weakening of the sea ice in the NEP region, which promoted the navigability of the NEP.

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Suppression of Arctic sea ice growth by winter clouds and snowfall

10.21203/rs.3.rs-84779/v1 ◽

2021 ◽

Author(s):

Won-il Lim ◽

Hyo-Seok Park ◽

Andrew Stewart ◽

Kyong-Hwan Seo

Keyword(s):

Sea Ice ◽

Longwave Radiation ◽

Arctic Sea Ice ◽

The Arctic ◽

Ice Thickness ◽

Sea Ice Thickness ◽

Ice Growth ◽

Downward Longwave Radiation ◽

Arctic Sea ◽

The Impact

Abstract The ongoing Arctic warming has been pronounced in winter and has been associated with an increase in downward longwave radiation. While previous studies have demonstrated that poleward moisture flux into the Arctic strengthens downward longwave radiation, less attention has been given to the impact of the accompanying increase in snowfall. Here, utilizing state-of-the art sea ice models, we show that typical winter snowfall anomalies of 1.0 cm, accompanied by positive downward longwave radiation anomalies of ~5 W m-2 can decrease sea ice thickness by around 5 cm in the following spring over the Eurasian Seas. This basin-wide ice thinning is followed by a shrinking of summer ice extent in extreme cases. In the winter of 2016–17, anomalously strong warm/moist air transport combined with ~2.5 cm increase in snowfall decreased spring ice thickness by ~10 cm and decreased the following summer sea ice extent by 5–30%. Projected future reductions in the thickness of Arctic sea ice and snow will amplify the impact of anomalous winter snowfall events on winter sea ice growth and seasonal sea ice thickness.

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