Calculation of northern hemisphere sea ice area using recurrent neural networks

Abstract Ice covering water surfaces causes difficulties for ship traffic in the northern regions. Developing a sustainable logistics system that describes and manages ship traffic requires consideration of many factors, one of which is the area of sea ice covering the waterways. Most of the volume of sea ice in the northern hemisphere is concentrated in the Arctic zone. The paper describes the process and results of data preparation and development of a recurrent neural network to determine the value of ice area change in the next 50 days relative to the last day of sea ice area measurement. The prediction is made based on the previous 30 measured values of sea ice area and a user-specified value of the day for which the prediction will be made. The work uses NSIDC open dataset on sea ice area for the northern hemisphere. This model allows us to calculate the change of sea ice area for 1 day ahead with an accuracy of 0.581%. For the 50-day prediction of ice area, the accuracy is 4.017%.

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Separating the influences of low-latitude warming and sea-ice loss on Northern Hemisphere climate change

Journal of Climate ◽

10.1175/jcli-d-21-0180.1 ◽

2022 ◽

pp. 1-59

Author(s):

Paul J. Kushner ◽

Russell Blackport ◽

Kelly E. McCusker ◽

Thomas Oudar ◽

Lantao Sun ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Northern Hemisphere ◽

North Atlantic ◽

High Latitude ◽

North Pacific ◽

Heat Fluxes ◽

The Arctic ◽

Low Latitude ◽

The Arctic Ocean

Abstract Analyzing a multi-model ensemble of coupled climate model simulations forced with Arctic sea-ice loss using a two-parameter pattern-scaling technique to remove the cross-coupling between low- and high-latitude responses, the sensitivity to high-latitude sea-ice loss is isolated and contrasted to the sensitivity to low-latitude warming. In spite of some differences in experimental design, the Northern Hemisphere near-surface atmospheric sensitivity to sea-ice loss is found to be robust across models in the cold season; however, a larger inter-model spread is found at the surface in boreal summer, and in the free tropospheric circulation. In contrast, the sensitivity to low-latitude warming is most robust in the free troposphere and in the warm season, with more inter-model spread in the surface ocean and surface heat flux over the Northern Hemisphere. The robust signals associated with sea-ice loss include upward turbulent and longwave heat fluxes where sea-ice is lost, warming and freshening of the Arctic ocean, warming of the eastern North Pacific relative to the western North Pacific with upward turbulent heat fluxes in the Kuroshio extension, and salinification of the shallow shelf seas of the Arctic Ocean alongside freshening in the subpolar North Atlantic. In contrast, the robust signals associated with low-latitude warming include intensified ocean warming and upward latent heat fluxes near the western boundary currents, freshening of the Pacific Ocean, salinification of the North Atlantic, and downward sensible and longwave fluxes over the ocean.

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Mid-Holocene Northern Hemisphere warming driven by Arctic amplification

Science Advances ◽

10.1126/sciadv.aax8203 ◽

2019 ◽

Vol 5 (12) ◽

pp. eaax8203 ◽

Cited By ~ 3

Author(s):

Hyo-Seok Park ◽

Seong-Joong Kim ◽

Andrew L. Stewart ◽

Seok-Woo Son ◽

Kyong-Hwan Seo

Keyword(s):

Sea Ice ◽

Northern Hemisphere ◽

High Latitude ◽

Climate Model ◽

Arctic Sea Ice ◽

The Arctic ◽

Arctic Amplification ◽

The Holocene ◽

Holocene Thermal Maximum ◽

Thermal Maximum

The Holocene thermal maximum was characterized by strong summer solar heating that substantially increased the summertime temperature relative to preindustrial climate. However, the summer warming was compensated by weaker winter insolation, and the annual mean temperature of the Holocene thermal maximum remains ambiguous. Using multimodel mid-Holocene simulations, we show that the annual mean Northern Hemisphere temperature is strongly correlated with the degree of Arctic amplification and sea ice loss. Additional model experiments show that the summer Arctic sea ice loss persists into winter and increases the mid- and high-latitude temperatures. These results are evaluated against four proxy datasets to verify that the annual mean northern high-latitude temperature during the mid-Holocene was warmer than the preindustrial climate, because of the seasonally rectified temperature increase driven by the Arctic amplification. This study offers a resolution to the “Holocene temperature conundrum”, a well-known discrepancy between paleo-proxies and climate model simulations of Holocene thermal maximum.

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A Model Simulation of 20 Years of Northern Hemisphere Sea-Ice Fluctuations

Annals of Glaciology ◽

10.3189/1984aog5-1-170-176 ◽

1984 ◽

Vol 5 ◽

pp. 170-176 ◽

Cited By ~ 1

Author(s):

John E. Walsh ◽

William D. Hibler ◽

Becky Ross

Keyword(s):

Sea Ice ◽

Northern Hemisphere ◽

Model Simulation ◽

Thickness Distribution ◽

Arctic Basin ◽

The Arctic ◽

Data Set ◽

Ice Dynamics ◽

Thermodynamic Computations ◽

Covered Area

A dynamic-thermodynamic sea-ice model (Hibler 1979) is used to simulate northern hemisphere sea ice for a 20-year period, 1961 to 1980. The model is driven by daily atmospheric grids of sea-level pressure (geo-strophic wind) and by temperatures derived from the Russian surface temperature data set. Among the modifications to earlier formulations are the inclusion of snow cover and a multilevel ice-thickness distribution in the thermodynamic computations.The time series of the simulated anomalies show relatively large amounts of ice during the early 1960s and middle 1970s, and relatively small amounts during the late 1960s and early 1970s. The fluctuations of ice mass, both in the entire domain and in individual regions, are more persistent than are the fluctuations of ice-covered area. The ice dynamics tend to introduce more high-frequency variability into the regional (and total) amounts of ice mass. The simulated annual ice export from the Arctic Basin into the East Greenland Sea varies interannually by factors of 3 to 4.

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Sea-ice and North Atlantic climate response to CO2-induced warming and cooling conditions

Journal of Glaciology ◽

10.3189/172756506781828566 ◽

2006 ◽

Vol 52 (178) ◽

pp. 433-439 ◽

Cited By ~ 1

Author(s):

Larissa Nazarenko ◽

Nickolai Tausnev ◽

James Hansen

Keyword(s):

Sea Ice ◽

Northern Hemisphere ◽

Surface Pressure ◽

Climate Model ◽

Global Climate Model ◽

Ice Cover ◽

The Arctic ◽

Normal Surface ◽

Sea Ice Extent ◽

Polar Cell

AbstractUsing a global climate model coupled with an ocean and a sea-ice model, we compare the effects of doubling CO2 and halving CO2 on sea-ice cover and connections with the atmosphere and ocean. An overall warming in the 2 × CO2 experiment causes reduction of sea-ice extent by 15%, with maximum decrease in summer and autumn, consistent with observed seasonal sea-ice changes. The intensification of the Northern Hemisphere circulation is reflected in the positive phase of the Arctic Oscillation (AO), associated with higher-than-normal surface pressure south of about 50° N and lower-than-normal surface pressure over the high northern latitudes. Strengthening the polar cell causes enhancement of westerlies around the Arctic perimeter during winter. Cooling, in the 0.5 × CO2 experiment, leads to thicker and more extensive sea ice. In the Southern Hemisphere, the increase in ice-covered area (28%) dominates the ice-thickness increase (5%) due to open ocean to the north. In the Northern Hemisphere, sea-ice cover increases by only 8% due to the enclosed land/sea configuration, but sea ice becomes much thicker (108%). Substantial weakening of the polar cell due to increase in sea-level pressure over polar latitudes leads to a negative trend of the winter AO index. The model reproduces large year-to-year variability under both cooling and warming conditions.

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Towards an automatic ice navigation support system in the Arctic area

10.32920/ryerson.14645892 ◽

2021 ◽

Author(s):

Shahram Sattar

Keyword(s):

Sea Ice ◽

Voronoi Diagram ◽

Support System ◽

The Arctic ◽

Navigation Systems ◽

Viable Solution ◽

Navigation Support ◽

Northern Regions ◽

Ice Navigation ◽

Arctic Area

Conventional ice navigation through sea ice is manually operated by well-trained navigators, whose experiences are heavily relied upon to guarantee the ship's safety. Despite increasingly available ice data and information, little has been done to develop automatic ice navigation systems to better guide ships in sea ice. In this study firstly navigable sea areas for different types of ships were identified according to the navigation codes in northern regions. Secondly, three algorithms of path planning were adopted to automatically compute the safest-and-shortest ship routes based on the concepts of the Voronoi diagram, Visibility graph, and Visibility-Voronoi diagram, respectively. These algorithms and results were compared and evaluated in terms of different application scenarios. Results show that the Visibility-Voronoi approach seems to be the best viable solution in terms of computing performance and navigation safety. The work will provide a basis for further development towards an automatic ice navigation support system

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Analysis of Foreign Experience in the Financial Regulation of the Arctic Territories Development and its Application in the Northern Regions of the Russian Federation

Arctic and North ◽

10.37482/issn2221-2698.2021.44.5 ◽

2021 ◽

pp. 5-29

Author(s):

Roman V. BADYLEVICH ◽

Keyword(s):

Financial Regulation ◽

Policy Instruments ◽

The Arctic ◽

Financial Policy ◽

Arctic Zone ◽

Foreign Experience ◽

Northern Regions ◽

The Usa ◽

The Russian Federation ◽

Regional Financial Policy

The article examines foreign experience in implementing regional financial policy in relation to the Arctic territories. It assesses the experience of such sub-arctic countries as Canada, Finland, Denmark, Norway, Sweden, and the USA. The paper identifies two groups of financial instruments of territorial devel-opment: within the framework of general regional policy (instruments of fiscal capacity equalization, taxa-tion instruments, instruments to increase investment attractiveness) and within the framework of special policy for the development of Arctic territories (program-targeted instruments, special development funds, direct allocation of funds for current expenses and development). It is concluded that the Arctic countries apply different approaches and tools to the development of the regions located in the Arctic zone, the choice of which is determined by the type of state structure, the degree of financial independence of the regions in the sphere of financial regulation, the level of development of the northernmost subjects compared to the rest of the country. In the conditions of Russia, it is possible to use the best foreign experience in the sphere of financial regulation of development of the regions located in the Arctic zone. In particular, it is possible to use the experience of applying program-targeted development tools, the formation of special development funds, which are based on revenues from the use of natural resources of the Arctic, as well as the experience of creating favourable conditions to attract investors for the implementation of economically attractive projects.

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Impact of Reduced Arctic Sea Ice on Northern Hemisphere Climate and Weather in Autumn and Winter

Journal of Climate ◽

10.1175/jcli-d-20-0515.1 ◽

2021 ◽

pp. 1-61

Author(s):

Svenya Chripko ◽

Rym Msadek ◽

Emilia Sanchez-Gomez ◽

Laurent Terray ◽

Laurent Bessières ◽

...

Keyword(s):

North America ◽

Sea Ice ◽

Central Asia ◽

Northern Hemisphere ◽

Climate Model ◽

Polar Vortex ◽

Arctic Sea Ice ◽

The Arctic ◽

Arctic Sea ◽

Autumn And Winter

AbstractThe Northern Hemisphere transient atmospheric response to Arctic sea decline is investigated in autumn and winter, using sensitivity experiments performed with the CNRMCM6-1 high-top climate model. Arctic sea ice albedo is reduced to the ocean value, yielding ice-free conditions during summer and a more moderate sea ice reduction during the following months. A strong ampli_cation of temperatures over the Arctic is induced by sea ice loss, with values reaching up to 25°C near the surface in autumn. Signi_cant surface temperature anomalies are also found over the mid-latitudes, with a warming reaching 1°C over North America and Europe, and a cooling reaching 1°C over central Asia. Using a dynamical adjustment method based on a regional reconstruction of circulation analogs, we show that the warming over North America and Europe can be explained both by changes in the atmospheric circulation and by the advection of warmer oceanic air by the climatological ow. In contrast, we demonstrate that the sea-ice induced cooling over central Asia is solely due to dynamical changes, involving an intensi_cation of the Siberian High and a cyclonic anomaly over the Sea of Okhotsk. In the troposphere, the abrupt Arctic sea ice decline favours a narrowing of the subtropical jet stream and a slight weakening of the lower part of the polar vortex that is explained by a weak enhancement of upward wave activity toward the stratosphere. We further show that reduced Arctic sea ice in our experiments is mainly associated with less severe cold extremes in the mid-latitudes.

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Autumn Sea Ice Cover, Winter Northern Hemisphere Annular Mode, and Winter Precipitation in Eurasia

Journal of Climate ◽

10.1175/jcli-d-12-00380.1 ◽

2012 ◽

Vol 26 (11) ◽

pp. 3968-3981 ◽

Cited By ~ 59

Author(s):

Fei Li ◽

Huijun Wang

Keyword(s):

Sea Ice ◽

Surface Temperature ◽

Northern Hemisphere ◽

Ice Cover ◽

Winter Precipitation ◽

The Arctic ◽

Northern Eurasia ◽

Laptev Sea ◽

Annular Mode ◽

Northern Hemisphere Annular Mode

Abstract This paper examines the impacts of the previous autumn sea ice cover (SIC) on the winter Northern Hemisphere annular mode (NAM) and winter precipitation in Eurasia. The coherent variations among the Kara–Laptev autumn SIC, winter NAM, and Eurasian winter precipitation appear after the year 1982, which may prove useful for seasonal prediction of winter precipitation. From a physical point of view, the Kara–Laptev SIC and sea surface temperature (SST) anomalies develop in autumn and remain in winter. Given that winter NAM is characterized by an Arctic–midlatitude seesaw centered over the Barents Sea and Kara–Laptev Seas, it is closely linked to the Arctic forcing that corresponds to the Kara–Laptev sea ice increase (reduction) and the associated surface temperature cooling (warming). Moreover, based on both model simulations and observations, the diminishing Kara–Laptev sea ice does induce positive sea level pressure (SLP) anomalies over high-latitude Eurasia in winter, which is accompanied by a significant surface warming in northern Eurasia and cooling south of the Mediterranean. This surface air temperature (SAT) anomaly pattern facilitates increases of specific humidity in northern Eurasia with a major ridge extending southward along the East Asian coast. As a result, the anomalous Eurasian winter precipitation has a more zonal band structure.

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Arctic sea ice variability and trends, 1979–2010

The Cryosphere ◽

10.5194/tc-6-881-2012 ◽

2012 ◽

Vol 6 (4) ◽

pp. 881-889 ◽

Cited By ~ 333

Author(s):

D. J. Cavalieri ◽

C. L. Parkinson

Keyword(s):

Sea Ice ◽

Northern Hemisphere ◽

Bering Sea ◽

Arctic Sea Ice ◽

Negative Trend ◽

The Arctic ◽

Sea Ice Extent ◽

Arctic Regions ◽

Arctic Sea ◽

The Bering Sea

Abstract. Analyses of 32 yr (1979–2010) of Arctic sea ice extents and areas derived from satellite passive microwave radiometers are presented for the Northern Hemisphere as a whole and for nine Arctic regions. There is an overall negative yearly trend of −51.5 ± 4.1 × 103 km2 yr−1 (−4.1 ± 0.3% decade−1) in sea ice extent for the hemisphere. The yearly sea ice extent trends for the individual Arctic regions are all negative except for the Bering Sea: −3.9 ± 1.1 × 103 km2 yr−1 (−8.7 ± 2.5% decade−1) for the Seas of Okhotsk and Japan, +0.3 ± 0.8 × 103 km2 yr−1 (+1.2 ± 2.7% decade−1) for the Bering Sea, −4.4 ± 0.7 × 103 km2 yr−1 (−5.1 ± 0.9% decade−1) for Hudson Bay, −7.6 ± 1.6 × 103 km2 yr−1 (−8.5 ± 1.8% decade−1) for Baffin Bay/Labrador Sea, −0.5 ± 0.3 × 103 km2 yr−1 (−5.9 ± 3.5% decade−1) for the Gulf of St. Lawrence, −6.5 ± 1.1 × 103 km2 yr−1 (−8.6 ± 1.5% decade−1) for the Greenland Sea, −13.5 ± 2.3 × 103 km2 yr−1 (−9.2 ± 1.6% decade−1) for the Kara and Barents Seas, −14.6 ± 2.3 × 103 km2 yr−1 (−2.1 ± 0.3% decade−1) for the Arctic Ocean, and −0.9 ± 0.4 × 103 km2 yr−1 (−1.3 ± 0.5% decade−1) for the Canadian Archipelago. Similarly, the yearly trends for sea ice areas are all negative except for the Bering Sea. On a seasonal basis for both sea ice extents and areas, the largest negative trend is observed for summer with the next largest negative trend being for autumn. Both the sea ice extent and area trends vary widely by month depending on region and season. For the Northern Hemisphere as a whole, all 12 months show negative sea ice extent trends with a minimum magnitude in May and a maximum magnitude in September, whereas the corresponding sea ice area trends are smaller in magnitude and reach minimum and maximum values in March and September.

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Alleviation of an arctic sea ice bias in a coupled model through modifications of the subgrid scale orographic parameterization

10.5194/egusphere-egu2020-9905 ◽

2020 ◽

Author(s):

Guillaume Gastineau ◽

Francois Lott ◽

Juliette Mignot ◽

Frederic Hourdin

Keyword(s):

Sea Ice ◽

Northern Hemisphere ◽

Storm Track ◽

Coupled Model ◽

Arctic Sea Ice ◽

The Arctic ◽

Subgrid Scale ◽

Local Flow ◽

Low Level ◽

Arctic Sea

In the IPSL-CM6A-LR model, the subgrid scale orography (SSO) parameterization imposes at low level a blocked flow drag opposed to the local flow and a lift that is perpendicular to the local flow. We suggest that their tuning impacts of the Arctic sea ice coverage and the large scale oceanic circulation in climate models. In forced atmospheric mode, increasing the blocking and reducing the lift leads to an equatorward shift of the Northern Hemisphere subtropical jet, and a reduction of the mid latitude eddy-driven jet. It improves the simulated variability, with a reduced storm-track, and increased blocking frequency over Greenland and Scandinavia. Second, it contributes to cool the polar low-troposphere in winter. We show that the reduction in eddy activity yields a reduction of the poleward heat fluxes in the low troposphere of the mid-latitudes and polar regions. Transformed Eulerian Mean diagnostics also show that there is a reduction of the low-level eddy-driven subsidence in the polar region consistent with the simulated cooling. The changes are amplified in the coupled model, as the eddy-driven jet shift further south. The low-troposphere polar cooling is further amplified by the temperature and albedo feedbacks in link with the Arctic sea-ice. This corrects the warm winter bias and the lack of sea-ice that were present over the Arctic without changing the SSO parameters. This also impacts the ocean, with an equatorward shift of the Northern Hemisphere oceanic gyre, and a weakening of the AMOC.

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