Validation of Sentinel-1-derived sea ice cover data in the Arctic

Abstract The Arctic amplification of global warming is causing the Arctic-Atlantic ice edge to retreat at unprecedented rates. Here we show how variability and change in sea ice cover in the Barents Sea, the largest shelf sea of the Arctic, affect the population dynamics of a keystone species of the ice-associated food web, the polar cod (Boreogadus saida). The data-driven biophysical model of polar cod early life stages assembled here predicts a strong mechanistic link between survival and variation in ice cover and temperature, suggesting imminent recruitment collapse should the observed ice-reduction and heating continue. Backtracking of drifting eggs and larvae from observations also demonstrates a northward retreat of one of two clearly defined spawning assemblages, possibly in response to warming. With annual to decadal ice-predictions under development the mechanistic physical-biological links presented here represent a powerful tool for making long-term predictions for the propagation of polar cod stocks.

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Contrasting trends in sea ice and primary production in the Bering Sea and Arctic Ocean

ICES Journal of Marine Science ◽

10.1093/icesjms/fss113 ◽

2012 ◽

Vol 69 (7) ◽

pp. 1180-1193 ◽

Cited By ~ 62

Author(s):

Zachary W. Brown ◽

Kevin R. Arrigo

Keyword(s):

Sea Ice ◽

Primary Production ◽

Arctic Ocean ◽

Bering Sea ◽

Net Primary Productivity ◽

Remote Sensing Data ◽

Ice Cover ◽

The Arctic ◽

Light Limitation ◽

The Bering Sea

Abstract Brown, Z. W., and Arrigo, K. R. 2012. Contrasting trends in sea ice and primary production in the Bering Sea and Arctic Ocean. – ICES Journal of Marine Science, 69: . Satellite remote sensing data were used to examine recent trends in sea-ice cover and net primary productivity (NPP) in the Bering Sea and Arctic Ocean. In nearly all regions, diminished sea-ice cover significantly enhanced annual NPP, indicating that light-limitation predominates across the seasonally ice-covered waters of the northern hemisphere. However, long-term trends have not been uniform spatially. The seasonal ice pack of the Bering Sea has remained consistent over time, partially because of winter winds that have continued to carry frigid Arctic air southwards over the past six decades. Hence, apart from the “Arctic-like” Chirikov Basin (where sea-ice loss has driven a 30% increase in NPP), no secular trends are evident in Bering Sea NPP, which averaged 288 ± 26 Tg C year−1 over the satellite ocean colour record (1998–2009). Conversely, sea-ice cover in the Arctic Ocean has plummeted, extending the open-water growing season by 45 d in just 12 years, and promoting a 20% increase in NPP (range 441–585 Tg C year−1). Future sea-ice loss will likely stimulate additional NPP over the productive Bering Sea shelves, potentially reducing nutrient flux to the downstream western Arctic Ocean.

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Low-frequency bursts of horizontally polarized waves in the Arctic sea-ice cover

Journal of Glaciology ◽

10.3189/002214311796405834 ◽

2011 ◽

Vol 57 (202) ◽

pp. 231-237 ◽

Cited By ~ 15

Author(s):

David Marsan ◽

Jérôme Weiss ◽

Jean-Philippe Métaxian ◽

Jacques Grangeon ◽

Pierre-François Roux ◽

...

Keyword(s):

Sea Ice ◽

Regional Scale ◽

Low Frequency ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Strong Activity ◽

Temporal Sampling ◽

Polarized Waves ◽

Arctic Sea

AbstractWe report the detection of bursts of low-frequency waves, typically f = 0.025 Hz, on horizontal channels of broadband seismometers deployed on the Arctic sea-ice cover during the DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies) experiment in spring 2007. These bursts have amplitudes well above the ambient ice swell and a lower frequency content. Their typical duration is of the order of minutes. They occur at irregular times, with periods of relative quietness alternating with periods of strong activity. A significant correlation between the rate of burst occurrences and the ice-cover deformation at the ∼400 km scale centered on the seismic network suggests that these bursts are caused by remote, episodic deformation involving shearing across regional-scale leads. This observation opens the possibility of complementing satellite measurements of ice-cover deformation, by providing a much more precise temporal sampling, hence a better characterization of the processes involved during these deformation events.

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Planetary and synoptic scale adjustment of the Arctic atmosphere to sea ice cover changes

Geophysical Research Letters ◽

10.1029/2007gl030218 ◽

2007 ◽

Vol 34 (17) ◽

Cited By ~ 15

Author(s):

E. Sokolova ◽

K. Dethloff ◽

A. Rinke ◽

A. Benkel

Keyword(s):

Sea Ice ◽

Ice Cover ◽

The Arctic ◽

Synoptic Scale ◽

Arctic Atmosphere

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Increasing Multiyear Sea Ice Loss in the Beaufort Sea: A New Export Pathway for the Diminishing Multiyear Ice Cover of the Arctic Ocean

10.1002/essoar.10509833.1 ◽

2021 ◽

Author(s):

David Gareth Babb ◽

Ryan J. Galley ◽

Stephen E. L. Howell ◽

Jack Christopher Landy ◽

Julienne Christine Stroeve ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Beaufort Sea ◽

Ice Cover ◽

The Arctic ◽

Export Pathway ◽

The Arctic Ocean ◽

Multiyear Ice

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Correlation and trend studies of the sea-ice cover and surface temperatures in the Arctic

Annals of Glaciology ◽

10.3189/172756402781818067 ◽

2002 ◽

Vol 34 ◽

pp. 420-428 ◽

Cited By ~ 14

Author(s):

Josefino C. Comiso

Keyword(s):

Sea Ice ◽

Surface Temperature ◽

Ice Cover ◽

The Arctic ◽

Temperature Anomalies ◽

Ice Concentration ◽

Arctic Ice ◽

Highly Correlated ◽

Surface Ice ◽

Perennial Ice

AbstractCo-registered and continuous satellite data of sea-ice concentrations and surface ice temperatures from 1981 to 2000 are analyzed to evaluate relationships between these two critical climate parameters and what they reveal in tandem about the changing Arctic environment. During the 19 year period, the Arctic ice extent and actual ice area are shown to be declining at a rate of –2.0±0.3% dec –1 and 3.1 ±0.4% dec–1, respectively, while the surface ice temperature has been increasing at 0.4 ±0.2 K dec–1, where dec is decade. The extent and area of the perennial ice cover, estimated from summer minimum values, have been declining at a much faster rate of –6.7±2.4% dec–1 and –8.3±2.4% dec–1, respectively, while the surface ice temperature has been increasing at 0.9 ±0.6K dec–1. This unusual rate of decline is accompanied by a very variable summer ice cover in the 1990s compared to the 1980s, suggesting increases in the fraction of the relatively thin second-year, and hence a thinning in the perennial, ice cover during the last two decades. Yearly anomaly maps show that the ice-concentration anomalies are predominantly positive in the 1980s and negative in the 1990s, while surface temperature anomalies were mainly negative in the 1980s and positive in the 1990s. The yearly ice-concentration and surface temperature anomalies are highly correlated, indicating a strong link especially in the seasonal region and around the periphery of the perennial ice cover. The surface temperature anomalies also reveal the spatial scope of each warming (or cooling) phenomenon that usually extends beyond the boundaries of the sea-ice cover.

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Late-Twentieth-Century Simulation of Arctic Sea Ice and Ocean Properties in the CCSM4

Journal of Climate ◽

10.1175/jcli-d-11-00201.1 ◽

2012 ◽

Vol 25 (5) ◽

pp. 1431-1452 ◽

Cited By ~ 82

Author(s):

Alexandra Jahn ◽

Kara Sterling ◽

Marika M. Holland ◽

Jennifer E. Kay ◽

James A. Maslanik ◽

...

Keyword(s):

Twentieth Century ◽

Sea Ice ◽

Internal Variability ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Motion Field ◽

Sea Ice Extent ◽

Arctic Sea ◽

Ensemble Mean

To establish how well the new Community Climate System Model, version 4 (CCSM4) simulates the properties of the Arctic sea ice and ocean, results from six CCSM4 twentieth-century ensemble simulations are compared here with the available data. It is found that the CCSM4 simulations capture most of the important climatological features of the Arctic sea ice and ocean state well, among them the sea ice thickness distribution, fraction of multiyear sea ice, and sea ice edge. The strongest bias exists in the simulated spring-to-fall sea ice motion field, the location of the Beaufort Gyre, and the temperature of the deep Arctic Ocean (below 250 m), which are caused by deficiencies in the simulation of the Arctic sea level pressure field and the lack of deep-water formation on the Arctic shelves. The observed decrease in the sea ice extent and the multiyear ice cover is well captured by the CCSM4. It is important to note, however, that the temporal evolution of the simulated Arctic sea ice cover over the satellite era is strongly influenced by internal variability. For example, while one ensemble member shows an even larger decrease in the sea ice extent over 1981–2005 than that observed, two ensemble members show no statistically significant trend over the same period. It is therefore important to compare the observed sea ice extent trend not just with the ensemble mean or a multimodel ensemble mean, but also with individual ensemble members, because of the strong imprint of internal variability on these relatively short trends.

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Antarctic sea ice variability and trends, 1979–2010

The Cryosphere Discussions ◽

10.5194/tcd-6-931-2012 ◽

2012 ◽

Vol 6 (2) ◽

pp. 931-956 ◽

Cited By ~ 16

Author(s):

C. L. Parkinson ◽

D. J. Cavalieri

Keyword(s):

Indian Ocean ◽

Sea Ice ◽

Ross Sea ◽

Ice Cover ◽

Weddell Sea ◽

The Arctic ◽

Future Research ◽

Positive Trend ◽

Antarctic Sea Ice ◽

Ice Coverage

Abstract. In sharp contrast to the decreasing sea ice coverage of the Arctic, in the Antarctic the sea ice cover has, on average, expanded since the late 1970s. More specifically, satellite passive-microwave data for the period November 1978–December 2010 reveal an overall positive trend in ice extents of 17 100 ± 2300 km2 yr−1. Much of the increase, at 13 700 ± 1500 km2 yr−1, has occurred in the region of the Ross Sea, with lesser contributions from the Weddell Sea and Indian Ocean. One region, that of the Bellingshausen/Amundsen Seas, has, like the Arctic, instead experienced significant sea ice decreases, with an overall ice extent trend of −8200 ± 1200 km2 yr−1. When examined through the annual cycle over the 32-yr period 1979–2010, the Southern Hemisphere sea ice cover as a whole experienced positive ice extent trends in every month, ranging in magnitude from a low of 9100 ± 6300 km2 yr−1 in February to a high of 24 700 ± 10 000 km2 yr−1 in May. The Ross Sea and Indian Ocean also had positive trends in each month, while the Bellingshausen/Amundsen Seas had negative trends in each month, and the Weddell Sea and Western Pacific Ocean had a mixture of positive and negative trends. Comparing ice-area results to ice-extent results, in each case the ice-area trend has the same sign as the ice-extent trend, but differences in the magnitudes of the two trends identify regions with overall increasing ice concentrations and others with overall decreasing ice concentrations. The strong pattern of decreasing ice coverage in the Bellingshausen/Amundsen Seas region and increasing ice coverage in the Ross Sea region is suggestive of changes in atmospheric circulation. This is a key topic for future research.

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Recent advances in understanding the Arctic climate system state and change from a sea ice perspective: a review

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-10929-2014 ◽

2014 ◽

Vol 14 (7) ◽

pp. 10929-10999 ◽

Cited By ~ 3

Author(s):

R. Döscher ◽

T. Vihma ◽

E. Maksimovich

Keyword(s):

Global Warming ◽

Sea Ice ◽

Ice Cover ◽

Arctic Sea Ice ◽

Climate System ◽

Arctic Climate ◽

The Arctic ◽

Atlantic Sector ◽

Sea Ice Decline ◽

Arctic Sea

Abstract. The Arctic sea ice is the central and essential component of the Arctic climate system. The depletion and areal decline of the Arctic sea ice cover, observed since the 1970's, have accelerated after the millennium shift. While a relationship to global warming is evident and is underpinned statistically, the mechanisms connected to the sea ice reduction are to be explored in detail. Sea ice erodes both from the top and from the bottom. Atmosphere, sea ice and ocean processes interact in non-linear ways on various scales. Feedback mechanisms lead to an Arctic amplification of the global warming system. The amplification is both supported by the ice depletion and is at the same time accelerating the ice reduction. Knowledge of the mechanisms connected to the sea ice decline has grown during the 1990's and has deepened when the acceleration became clear in the early 2000's. Record summer sea ice extents in 2002, 2005, 2007 and 2012 provided additional information on the mechanisms. This article reviews recent progress in understanding of the sea ice decline. Processes are revisited from an atmospheric, ocean and sea ice perspective. There is strong evidence for decisive atmospheric changes being the major driver of sea ice change. Feedbacks due to reduced ice concentration, surface albedo and thickness allow for additional local atmosphere and ocean influences and self-supporting feedbacks. Large scale ocean influences on the Arctic Ocean hydrology and circulation are highly evident. Northward heat fluxes in the ocean are clearly impacting the ice margins, especially in the Atlantic sector of the Arctic. Only little indication exists for a direct decisive influence of the warming ocean on the overall sea ice cover, due to an isolating layer of cold and fresh water underneath the sea ice.

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Sea ice drift in the Southern Ocean: Regional patterns, variability, and trends

Elem Sci Anth ◽

10.1525/elementa.226 ◽

2017 ◽

Vol 5 ◽

Cited By ~ 17

Author(s):

Ron Kwok ◽

Shirley S. Pang ◽

Sahra Kacimi

Keyword(s):

Southern Ocean ◽

Sea Ice ◽

Sea Level ◽

Ice Cover ◽

The Arctic ◽

Positive Trend ◽

Amundsen Sea ◽

Regional Patterns ◽

Ice Drift ◽

Sea Ice Drift

Understanding long-term changes in large-scale sea ice drift in the Southern Ocean is of considerable interest given its contribution to ice extent, to ice production in open waters, with associated dense water formation and heat flux to the atmosphere, and thus to the climate system. In this paper, we examine the trends and variability of this ice drift in a 34-year record (1982–2015) derived from satellite observations. Uncertainties in drift (~3 to 4 km day–1) were assessed with higher resolution observations. In a linear model, drift speeds were ~1.4% of the geostrophic wind from reanalyzed sea-level pressure, nearly 50% higher than that of the Arctic. This result suggests an ice cover in the Southern Ocean that is thinner, weaker, and less compact. Geostrophic winds explained all but ~40% of the variance in ice drift. Three spatially distinct drift patterns were shown to be controlled by the location and depth of atmospheric lows centered over the Amundsen, Riiser-Larsen, and Davis seas. Positively correlated changes in sea-level pressures at the three centers (up to 0.64) suggest correlated changes in the wind-driven drift patterns. Seasonal trends in ice edge are linked to trends in meridional winds and also to on-ice/off-ice trends in zonal winds, due to zonal asymmetry of the Antarctic ice cover. Sea ice area export at flux gates that parallel the 1000-m isobath were extended to cover the 34-year record. Interannual variability in ice export in the Ross and Weddell seas linked to the depth and location of the Amundsen Sea and Riiser-Larsen Sea lows to their east. Compared to shorter records, where there was a significant positive trend in Ross Sea ice area flux, the longer 34-year trends of outflow from both seas are now statistically insignificant.

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