Investigating the anomalous sea-ice conditions in the Canadian High Arctic (Queen Elizabeth Islands) during summer 1998

AbstractThe Queen Elizabeth Islands of the Canadian Arctic Archipelago exhibit one of the most complex sea-ice regimes in the Northern Hemisphere. Time series of minimum monthly passive-microwave sea-ice area (1979−98), minimum sea-ice extent, melting degree-days (1961−98) and minimum sea ice from the new Canadian Ice Service digital database (1968−98) are examined. The extreme nature of the amount of sea-ice melt in the summers of 1998 and 1962 is evident in these time series. The 38 year record of minimum ice, to date, shows no significant trend. Details of the sea-ice behavior during summer 1998 were then examined within 13 individual sea-ice regimes. The multi-year fast-ice plugs in both Sverdrup Channel and Nansen Sound broke up and became truly mobile in 1998. Discussion focuses on the areas surrounding the multi-year plugs, relating sea-ice conditions to weather. Results emphasize the importance of the timing of synoptic events in combination with strong thermal preconditioning in determining the sea-ice conditions in this area during summer 1998.

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Arctic sea ice extent and thickness

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1995.0072 ◽

1995 ◽

Vol 352 (1699) ◽

pp. 301-319 ◽

Cited By ~ 17

Keyword(s):

Sea Ice ◽

Open Water ◽

Arctic Sea Ice ◽

The Arctic ◽

Ice Thickness ◽

Sea Ice Extent ◽

Arctic Sea ◽

Ice Conditions ◽

Fast Ice ◽

Arctic Sea Ice Extent

Current knowledge on Arctic sea ice extent and thickness variability is reviewed, and we examine whether measurements to date provide evidence for the impact of climate change. The total Arctic ice extent has shown a small but significant reduction of (2.1 ± 0.9)% during the period 1978-87, after apparently increasing from a lower level in the early 1970s. However, open water within the pack ice limit has also diminished, so that the reduction of sea ice area is only (1.8 ± 1.2)%. This stability conceals large interannual variations and trends in individual regions of the Arctic Ocean and sub-Arctic seas, which are out of phase with one another and so have little net impact on the overall hemispheric ice extent. The maximum annual global extent (occurring during the Antarctic winter) shows a more significant decrease of 5% during 1972-87. Ice thickness distribution has been measured by submarine sonar profiling, moored upward sonars, airborne laser prohlometry, airborne electromagnetic techniques and drilling. Promising new techniques include: sonar mounted on an AUV or neutrally buoyant float; acoustic tomography or thermometry; and inference from a combination of microwave sensors. In relation to climate change, the most useful measurement has been repeated submarine sonar profiling under identical parts of the Arctic, which offers some evidence of a decline in mean ice thickness in the 1980s compared to the 1970s. The link between mean ice thickness and climatic warming is complex because of the effects of dynamics and deformation. Only fast ice responds primarily to air temperature changes and one can predict thinning of fast ice and extension of the open water season in fast ice areas. Another region of increasingly mild ice conditions is the central Greenland Sea where winter thermohaline convection is triggered by cyclic growth and melt of local young ice. In recent years convection to the bottom has slowed or ceased, possibly related to moderation of ice conditions.

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Interannual sea ice thickness variability in the Bay of Bothnia

The Cryosphere ◽

10.5194/tc-12-3459-2018 ◽

2018 ◽

Vol 12 (11) ◽

pp. 3459-3476 ◽

Cited By ~ 5

Author(s):

Iina Ronkainen ◽

Jonni Lehtiranta ◽

Mikko Lensu ◽

Eero Rinne ◽

Jari Haapala ◽

...

Keyword(s):

Sea Ice ◽

Interannual Variability ◽

Thickness Distribution ◽

Ice Thickness ◽

Data Sets ◽

Sea Ice Extent ◽

Sea Ice Thickness ◽

Thickness Variability ◽

Fast Ice ◽

Ridged Ice

Abstract. While variations of Baltic Sea ice extent and thickness have been extensively studied, there is little information about drift ice thickness, distribution, and its variability. In our study, we quantify the interannual variability of sea ice thickness in the Bay of Bothnia during the years 2003–2016. We use various different data sets: official ice charts, drilling data from the regular monitoring stations in the coastal fast ice zone, and helicopter and shipborne electromagnetic soundings. We analyze the different data sets and compare them to each other to characterize the interannual variability, to discuss the ratio of level and deformed ice, and to derive ice thickness distributions in the drift ice zone. In the fast ice zone the average ice thickness is 0.58±0.13 m. Deformed ice increases the variability of ice conditions in the drift ice zone, where the average ice thickness is 0.92±0.33 m. On average, the fraction of deformed ice is 50 % to 70 % of the total volume. In heavily ridged ice regions near the coast, mean ice thickness is approximately half a meter thicker than that of pure thermodynamically grown fast ice. Drift ice exhibits larger interannual variability than fast ice.

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Land-fast ice microalgal and phytoplanktonic communities (Adélie Land, Antarctica) in relation to environmental factors during ice break-up

Antarctic Science ◽

10.1017/s0954102003001378 ◽

2003 ◽

Vol 15 (3) ◽

pp. 353-364 ◽

Cited By ~ 19

Author(s):

C. RIAUX-GOBIN ◽

M. POULIN ◽

R. PRODON ◽

P. TREGUER

Keyword(s):

Sea Ice ◽

Early Spring ◽

Ice Melt ◽

Fast Ice ◽

Maximum Cell ◽

Cell Densities ◽

Ice Water ◽

Water Species ◽

Very High ◽

Pennate Diatoms

Annual land-fast ice, particularly an unconsolidated layer or “platelet ice-like” layer (PLI), was sampled in spring 1995 to study the spatial and short-term variations of ice-associated diatoms. Under-ice water, a lead and small polynyas were also sampled. Along a 7 km seaward transect a geographical gradient was evident, with some rare diatom species present only in the offshore PLI, whereas others (mainly pennate diatoms) were ubiquitous. The dense microphytic PLI community as well as the phytoplankton was diatom-dominated, but, within these two communities, marked differences appeared. First, the sea-ice communities (PLI and solid bottom ice) were moderately diverse (36 species), mostly composed of pennate diatoms, of which many were chain forming or tube-dwelling. Dominant taxa were Navicula glaciei, Berkeleya adeliensis, Nitzschia stellata, Amphiprora kufferathii and Nitzschia lecointei. Some differences in the distribution of the most dominant species appeared within the bottom ice and the PLI, attesting to differences in the origin or/and growing capability of these diatoms in these two ice compartments. Under-ice water species composition was mixed with sea-ice communities only on the most coastal sites and during ice melt. Maximum cell numbers were mostly noticed in the PLI, reaching up to 1010 cells l−1 and very high Chl a concentrations (exceptionally up to 9.8 mg Chl a l−1 or 1.9 g Chl a m−2, from a 10 to 20 cm thick PLI layer, close to the continent). Secondly, the phytoplankton in the lead and small polynyas had a low diversity, very low standing stocks (on an average 0.69 μg Chl a l−1) and cell densities (2 × 104 cells l−1). Some species from the polynyas were similar to those of the PLI, such as Navicula glaciei, but others were typically planktonic, such as Chaetoceros cf. neglectus. The presence of encysted cells (Chaetoceros and Chrysophytes) was also noticeable in the polynya water. In early spring no seeding process was obvious from the PLI to polynya water. A comparison with similar fast-ice diatom communities in other parts of coastal Antarctica, is presented.

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Arctic seabirds and shrinking sea ice: egg analyses reveal the importance of ice-derived resources

Scientific Reports ◽

10.1038/s41598-019-51788-4 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Fanny Cusset ◽

Jérôme Fort ◽

Mark Mallory ◽

Birgit Braune ◽

Philippe Massicotte ◽

...

Keyword(s):

Sea Ice ◽

Marine Species ◽

Arctic Sea Ice ◽

The Arctic ◽

Sea Ice Extent ◽

Climate Shifts ◽

Investment In Reproduction ◽

Ice Conditions ◽

Arctic Seabirds ◽

Energetic Composition

Abstract In the Arctic, sea-ice plays a central role in the functioning of marine food webs and its rapid shrinking has large effects on the biota. It is thus crucial to assess the importance of sea-ice and ice-derived resources to Arctic marine species. Here, we used a multi-biomarker approach combining Highly Branched Isoprenoids (HBIs) with δ13C and δ15N to evaluate how much Arctic seabirds rely on sea-ice derived resources during the pre-laying period, and if changes in sea-ice extent and duration affect their investment in reproduction. Eggs of thick-billed murres (Uria lomvia) and northern fulmars (Fulmarus glacialis) were collected in the Canadian Arctic during four years of highly contrasting ice conditions, and analysed for HBIs, isotopic (carbon and nitrogen) and energetic composition. Murres heavily relied on ice-associated prey, and sea-ice was beneficial for this species which produced larger and more energy-dense eggs during icier years. In contrast, fulmars did not exhibit any clear association with sympagic communities and were not impacted by changes in sea ice. Murres, like other species more constrained in their response to sea-ice variations, therefore appear more sensitive to changes and may become the losers of future climate shifts in the Arctic, unlike more resilient species such as fulmars.

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Fast Ice Prediction System (FIPS) for land-fast sea ice at Prydz Bay, East Antarctica: an operational service for CHINARE

Annals of Glaciology ◽

10.1017/aog.2020.46 ◽

2020 ◽

pp. 1-13

Author(s):

Jiechen Zhao ◽

Bin Cheng ◽

Timo Vihma ◽

Petra Heil ◽

Fengming Hui ◽

...

Keyword(s):

Sea Ice ◽

Ice Thickness ◽

Cold Bias ◽

Prediction System ◽

Atmospheric Forcing ◽

Ice Melt ◽

Fast Ice ◽

Sar Imagery ◽

Operational Service ◽

Snow And Ice

Abstract A Fast Ice Prediction System (FIPS) was constructed and is the first regional land-fast sea-ice forecasting system for the Antarctic. FIPS had two components: (1) near-real-time information on the ice-covered area from MODIS and SAR imagery that revealed, tidal cracks, ridged and rafted ice regions; (2) a high-resolution 1-D thermodynamic snow and ice model (HIGHTSI) that was extended to perform a 2-D simulation on snow and ice evolution using atmospheric forcing from ECMWF: either using ERA-Interim reanalysis (in hindcast mode) or HERS operational 10-day predictions (in forecast mode). A hindcast experiment for the 2015 season was in good agreement with field observations, with a mean bias of 0.14 ± 0.07 m and a correlation coefficient of 0.98 for modeled ice thickness. The errors are largely caused by a cold bias in the atmospheric forcing. The thick snow cover during the 2015 season led to modeled formation of extensive snow ice and superimposed ice. The first FIPS operational service was performed during the 2017/18 season. The system predicted a realistic ice thickness and onset of snow surface melt as well as the area of internal ice melt. The model results on the snow and ice properties were considered by the captain of R/V Xuelong when optimizing a low-risk route for on-ice transportation through fast ice to the coastal Zhongshan Station.

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Sea ice metadata for Billefjorden and Grnfjorden, Svalbard

Czech Polar Reports ◽

10.5817/cpr2014-2-13 ◽

2014 ◽

Vol 4 (2) ◽

pp. 129-139 ◽

Cited By ~ 1

Author(s):

Boris V. Ivanov ◽

Pavel N. Sviashchennikov ◽

Danila M. Zhuravskiy ◽

Alexey K. Pavlov ◽

Eirik J. Frland ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

State Archive ◽

Sea Ice Extent ◽

Sea Transport ◽

Local Climate ◽

Antarctic Research Institute ◽

Instrumental Observations ◽

Ice Conditions ◽

Antarctic Research

Description of sea ice conditions in the fjords of Svalbard is crucial for sea transport as well as studies of local climate and climate change. Old observations from the Russian Hydrometeorological stations in the mining settlements Barentsburg (Grnfjorden) and Pyramiden (Billefjorden) have now been digitized. These visual and instrumental observations are archived in the State Archive of Arctic and Antarctic Research Institute (AARI) and Murmansk Branch of the Russian Hydrometeorological Service. In this paper, we bring an overview of the sea ice metadata with few examples of yearly changes in sea ice extent.

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Sea ice and atmosphere interactions and predictability: preliminary results using HadGEM3

10.5194/egusphere-egu2020-13771 ◽

2020 ◽

Author(s):

Daniela Flocco ◽

Ed Hawkins ◽

Leandro Ponsoni ◽

Francois Massonnet ◽

Daniel Feltham ◽

...

Keyword(s):

Sea Ice ◽

Initial Conditions ◽

Complete Information ◽

Arctic Sea Ice ◽

The Arctic ◽

Sea Ice Extent ◽

Sea Level Pressure ◽

Sea Ice Thickness ◽

Climate Forecasts ◽

Ice Conditions

Arctic sea ice extent has steadily declined in the past 30 years. Aside from the global impact on climate change, regional information on the sea ice presence and on its impact on oceanic and atmospheric patterns has witnessed a growing interest. There is a growing need for seasonal-to-decadal timescale climate forecasts to help inform local communities and industry stakeholders.Here we examine the influence of sea-ice thickness observations on the predictability of the sea-ice and atmospheric circulation. We perform paired sets of ensembles with the HadGEM3 GCM starting from different initial conditions in a present-day control run. One set of ensembles start with complete information about the sea-ice conditions, and one set have degraded information. We investigate how the pairs of ensembles predict the subsequent evolution of the sea-ice, sea level pressure and circulation within the Arctic and beyond with the aim of quantifying the value of sea-ice observations for improving predictions.

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Arctic Ocean Sea Ice Area Extent Cyclicity and Non-Stationarity

10.5194/egusphere-egu2020-5915 ◽

2020 ◽

Author(s):

Reginald Muskett ◽

Syun-Ichi Akasofu

Keyword(s):

Time Series ◽

Sea Ice ◽

Wave Pattern ◽

Arctic Sea Ice ◽

The Arctic ◽

Weather System ◽

Sea Ice Extent ◽

Temperature Variations ◽

Arctic Sea ◽

Arctic Temperature

Arctic sea ice is a key component of the Arctic hydrologic cycle. This cycle is connected to land and ocean temperature variations and Arctic snow cover variations, spatially and temporally. Arctic temperature variations from historical observations shows an early 20th century increase (i.e. warming), followed by a period of Arctic temperature decrease (i.e. cooling) since the 1940s, which was followed by another period of Arctic temperature increase since the 1970s that continues into the two decades of the 21st century. Evidence has been accumulating that Arctic sea ice extent can experience multi-decadal to centennial time scale variations as it is a component of the Arctic Geohydrological System.&#160; We investigate the multi-satellite and sensor daily values of area extent of Arctic sea ice since SMMR on Nimbus 7 (1978) to AMSR2 on GCOM-W1 (2019). From the daily time series we use the first year-cycle as a wave-pattern to compare to all subsequent years-cycles through April 2020 (in progress), and constitute a derivative time series. In this time series we find the emergence of a multi-decadal cycle, showing a relative minimum during the period of 2007 to 2014, and subsequently rising. This may be related to an 80-year cycle (hypothesis). The Earth&#8217;s weather system is principally driven the solar radiation and its variations. If the multi-decadal cycle in Arctic sea ice area extent that we interpret continues, it may be linked physically to the Wolf-Gleissberg cycle, a factor in the variations of terrestrial cosmogenic isotopes, ocean sediment layering and glacial varves, ENSO and Aurora.Our hypothesis and results give more evidence that the multi-decadal variation of Arctic sea ice area extent is controlled by natural physical processes of the Sun-Earth system.&#160;

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Comparison of sea-ice extent and ice-edge location estimates from passive microwave and enhanced-resolution scatterometer data

Annals of Glaciology ◽

10.3189/172756408784700743 ◽

2008 ◽

Vol 48 ◽

pp. 65-70 ◽

Cited By ~ 32

Author(s):

Walter N. Meier ◽

Julienne Stroeve

Keyword(s):

Sea Ice ◽

Resolution Enhancement ◽

Passive Microwave ◽

Sea Ice Concentration ◽

Sea Ice Extent ◽

Local Conditions ◽

Enhanced Resolution ◽

Edge Location ◽

Ice Conditions ◽

Ice Edge

AbstractPassive microwave sea-ice concentration fields provide some of the longest-running and most consistent records of changes in sea ice. Scatterometry-based sea-ice fields are more recently developed data products, but now they provide a record of ice conditions spanning several years. Resolution enhancement techniques applied to scatterometer fields provide much higher effective resolutions (~10 km) than are available from standard scatterometer and passive microwave fields (25–50 km). Here we examine ice-extent fields from both sources and find that there is general agreement between scatterometer data and passive microwave fields, though scatterometer estimates yield substantially lower ice extents during winter. Comparisons with ice-edge locations estimated from AVHRR imagery indicate that enhanced scatterometer data can sometimes provide an improved edge location, but there is substantial variation in the results, depending on the local conditions. A blended product, using both scatterometer and passive microwave data, could yield improved results.

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