Autumn Arctic Pacific Sea Ice Dipole as a Source of Predictability for Subsequent Spring Barents Sea Ice Condition

AbstractThis study uses observational and reanalysis datasets in 1980–2016 to show a close connection between a boreal autumn sea ice dipole in the Arctic Pacific sector and sea ice anomalies in the Barents Sea (BS) during the following spring. The September–October Arctic Pacific sea ice dipole variations are highly correlated with the subsequent April–May BS sea ice variations (r = 0.71). The strong connection between the regional sea ice variabilities across the Arctic uncovers a new source of predictability for spring BS sea ice prediction at 7-month lead time. A cross-validated linear regression prediction model using the Arctic Pacific sea ice dipole with 7-month lead time is demonstrated to have significant prediction skills with 0.54–0.85 anomaly correlation coefficients. The autumn sea ice dipole, manifested as sea ice retreat in the Beaufort and Chukchi Seas and expansion in the East Siberian and Laptev Seas, is primarily forced by preceding atmospheric shortwave anomalies from late spring to early autumn. The spring BS sea ice increases are mostly driven by an ocean-to-sea ice heat flux reduction in preceding months, associated with reduced horizontal ocean heat transport into the BS. The dynamical linkage between the two regional sea ice anomalies is suggested to involve positive stratospheric polar cap anomalies during autumn and winter, with its center slowly moving toward Greenland. The migration of the stratospheric anomalies is followed in midwinter by a negative North Atlantic Oscillation–like pattern in the troposphere, leading to reduced ocean heat transport into the BS and sea ice extent increase.

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The role of ocean heat transport from the Atlantic into the Arctic Ocean on sea ice variability

10.5194/egusphere-egu21-3280 ◽

2021 ◽

Author(s):

David Schroeder ◽

Danny Feltham

Keyword(s):

Sea Ice ◽

Heat Transport ◽

Barents Sea ◽

System Model ◽

The Arctic ◽

Earth System ◽

Ocean Heat Transport ◽

Sea Ice Extent ◽

Atmospheric Processes

The decrease of Arctic sea ice affects the future climate in the Arctic and beyond. Therefore, it is important to understand the drivers of sea ice variability and trend. Previous model studies found that the summer sea ice is mainly driven by atmospheric processes (incoming radiation and albedo feedback) and the winter sea ice extent by ocean processes (ocean heat transport from Atlantic into Arctic Ocean, e.g. applying Community Earth System Model large ensemble simulation). In our study, we analyse a historical simulation with the UK Earth System Model (UKESM1) performed for CMIP6 from 1850 to 2014 and ocean &#8211; sea ice simulations forced by atmospheric reanalysis data with the same ocean model NEMOv3.6 and sea ice model CICEv5.1. The UKESM simulation confirms previous findings showing that the ocean heat transport between Norway and Svalbard (Barents Sea Opening; BSO) is strongly correlated with the winter (and annual) sea ice extent in the Barents Sea and the whole Arctic. However, there is no correlation in the atmospheric-forced simulations suggesting that the interaction between atmosphere and ocean is crucial. We will present sensitivity simulations showing the impact of atmospheric forcing data on the BSO heat flux and analyse the role of atmospheric processes (large scale circulation, cloud formation) on winter sea ice conditions.

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Atmospheric and oceanic drivers of regional Arctic winter sea-ice variability in present and future climates

10.5194/egusphere-egu21-2231 ◽

2021 ◽

Author(s):

Jakob Dörr ◽

Marius Årthun ◽

Tor Eldevik ◽

Erica Madonna

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Heat Transport ◽

Barents Sea ◽

Arctic Sea Ice ◽

The Arctic ◽

Ocean Heat Transport ◽

The Pacific ◽

Arctic Sea ◽

The Arctic Ocean

The recent retreat of Arctic sea ice area is overlaid by strong internal variability on all timescales. In winter, sea ice retreat and variability are currently dominated by the Barents Sea, primarily driven by variable ocean heat transport from the Atlantic. Climate models from the latest intercomparison project CMIP6 project that the future loss of winter Arctic sea ice spreads throughout the Arctic Ocean and, hence, that other regions of the Arctic Ocean will see increased sea-ice variability. It is, however, not known how the influence of ocean heat transport will change, and to what extent and in which regions other drivers, such as atmospheric circulation or river runoff into the Arctic Ocean, will become important. Using a combination of observations and simulations from the Community Earth System Model Large Ensemble (CESM-LE), we analyze and contrast the present and future regional drivers of the variability of the winter Arctic sea ice cover. We find that for the recent past, both observations and CESM-LE show that sea ice variability in the Atlantic and Pacific sector of the Arctic Ocean is influenced by ocean heat transport through the Barents Sea and Bering Strait, respectively. The two dominant modes of large-scale atmospheric variability &#8211; the Arctic Oscillation and the Pacific North American pattern &#8211; are only weakly related to recent regional sea ice variability. However, atmospheric circulation anomalies associated with regional sea ice variability show distinct patterns for the Atlantic and Pacific sectors consistent with heat and humidity transport from lower latitudes. In the future, under a high emission scenario, CESM-LE projects a gradual expansion of the footprint of the Pacific and Atlantic inflows, covering the whole Arctic Ocean by 2050-2079. This study highlights the combined importance of future Atlantification and Pacification of the Arctic Ocean and improves our understanding of internal climate variability which essential in order to predict future sea ice changes under anthropogenic warming.&#160; &#160;&#160;

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Quantifying the Influence of Atlantic Heat on Barents Sea Ice Variability and Retreat*

Journal of Climate ◽

10.1175/jcli-d-11-00466.1 ◽

2012 ◽

Vol 25 (13) ◽

pp. 4736-4743 ◽

Cited By ~ 228

Author(s):

M. Årthun ◽

T. Eldevik ◽

L. H. Smedsrud ◽

Ø. Skagseth ◽

R. B. Ingvaldsen

Keyword(s):

Sea Ice ◽

Heat Transport ◽

Barents Sea ◽

Heat Budget ◽

Heat Content ◽

Ocean Model ◽

Sea Ice Extent ◽

The Barents Sea ◽

Ice Retreat ◽

Sea Ice Retreat

Abstract The recent Arctic winter sea ice retreat is most pronounced in the Barents Sea. Using available observations of the Atlantic inflow to the Barents Sea and results from a regional ice–ocean model the authors assess and quantify the role of inflowing heat anomalies on sea ice variability. The interannual variability and longer-term decrease in sea ice area reflect the variability of the Atlantic inflow, both in observations and model simulations. During the last decade (1998–2008) the reduction in annual (July–June) sea ice area was 218 × 103 km2, or close to 50%. This reduction has occurred concurrent with an increase in observed Atlantic heat transport due to both strengthening and warming of the inflow. Modeled interannual variations in sea ice area between 1948 and 2007 are associated with anomalous heat transport (r = −0.63) with a 70 × 103 km2 decrease per 10 TW input of heat. Based on the simulated ocean heat budget it is found that the heat transport into the western Barents Sea sets the boundary of the ice-free Atlantic domain and, hence, the sea ice extent. The regional heat content and heat loss to the atmosphere scale with the area of open ocean as a consequence. Recent sea ice loss is thus largely caused by an increasing “Atlantification” of the Barents Sea.

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Ocean Heat Transport as a Cause for Model Uncertainty in Projected Arctic Warming

Journal of Climate ◽

10.1175/2010jcli3713.1 ◽

2011 ◽

Vol 24 (5) ◽

pp. 1451-1460 ◽

Cited By ~ 56

Author(s):

Irina Mahlstein ◽

Reto Knutti

Keyword(s):

Sea Ice ◽

Heat Transport ◽

General Circulation ◽

General Circulation Models ◽

Arctic Sea Ice ◽

The Arctic ◽

Ocean Heat Transport ◽

Sea Ice Extent ◽

Arctic Sea ◽

Future Warming

Abstract The Arctic climate is governed by complex interactions and feedback mechanisms between the atmosphere, ocean, and solar radiation. One of its characteristic features, the Arctic sea ice, is very vulnerable to anthropogenically caused warming. Production and melting of sea ice is influenced by several physical processes. The authors show that the northward ocean heat transport is an important factor in the simulation of the sea ice extent in the current general circulation models. Those models that transport more energy to the Arctic show a stronger future warming, in the Arctic as well as globally. Larger heat transport to the Arctic, in particular in the Barents Sea, reduces the sea ice cover in this area. More radiation is then absorbed during summer months and is radiated back to the atmosphere in winter months. This process leads to an increase in the surface temperature and therefore to a stronger polar amplification. The models that show a larger global warming agree better with the observed sea ice extent in the Arctic. In general, these models also have a higher spatial resolution. These results suggest that higher resolution and greater complexity are beneficial in simulating the processes relevant in the Arctic and that future warming in the high northern latitudes is likely to be near the upper range of model projections, consistent with recent evidence that many climate models underestimate Arctic sea ice decline.

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Ocean heat transport as a driver of sea ice extent in CMIP6 models

10.5194/egusphere-egu21-2170 ◽

2021 ◽

Author(s):

Jake Aylmer ◽

David Ferreira ◽

Daniel Feltham

Keyword(s):

Sea Ice ◽

Heat Transport ◽

Surface Fluxes ◽

The Arctic ◽

Balance Model ◽

Climate Projections ◽

Ocean Heat Transport ◽

Sea Ice Extent ◽

Atlantic Sector ◽

The Mean

Estimating long-term projections of sea ice extent is a key part of understanding the possible future climate state. This is hampered by uncertainties within and across comprehensive climate models, and the relative importance and nature of contributing factors are not fully understood. Here, we investigate the role of ocean and atmospheric forcing on sea ice on multidecadal time scales.Pre-industrial control simulations of 19 CMIP6 models are analysed. Sea ice extent is negatively correlated with ocean heat transport (OHT), and positively correlated with atmospheric heat (moist-static energy) transport (AHT), in both hemispheres. In most models, increased OHT into the Arctic enhances surface fluxes in the Atlantic sector just south of the sea ice edge, which in turn increases the AHT convergence at higher latitudes. In the southern ocean, increased OHT directly increases the mean ocean&#8211;ice heat flux while AHT plays no direct role. Sensitivities of the sea ice cover to OHT are consistent with predictions from an idealised energy balance model (EBM), which is fitted to each model in turn. This shows that the sensitivities are constrained by atmospheric radiation parameters and the mean surface temperature response, with no explicit dependence on ocean parameters. These results are a step towards quantifying the effect of ocean biases on sea ice uncertainty in climate projections.

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Record high Pacific Arctic seawater temperatures and delayed sea ice advance in response to episodic atmospheric blocking

Scientific Reports ◽

10.1038/s41598-020-77488-y ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Tsubasa Kodaira ◽

Takuji Waseda ◽

Takehiko Nose ◽

Jun Inoue

Keyword(s):

Sea Ice ◽

Arctic Region ◽

Arctic Sea Ice ◽

Sea Surface ◽

The Arctic ◽

Atmospheric Blocking ◽

Sea Ice Extent ◽

The Pacific ◽

Arctic Sea ◽

Highly Correlated

AbstractArctic sea ice is rapidly decreasing during the recent period of global warming. One of the significant factors of the Arctic sea ice loss is oceanic heat transport from lower latitudes. For months of sea ice formation, the variations in the sea surface temperature over the Pacific Arctic region were highly correlated with the Pacific Decadal Oscillation (PDO). However, the seasonal sea surface temperatures recorded their highest values in autumn 2018 when the PDO index was neutral. It is shown that the anomalous warm seawater was a rapid ocean response to the southerly winds associated with episodic atmospheric blocking over the Bering Sea in September 2018. This warm seawater was directly observed by the R/V Mirai Arctic Expedition in November 2018 to significantly delay the southward sea ice advance. If the atmospheric blocking forms during the PDO positive phase in the future, the annual maximum Arctic sea ice extent could be dramatically reduced.

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Mechanisms for low-frequency variability of summer Arctic sea ice extent

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1422296112 ◽

2015 ◽

Vol 112 (15) ◽

pp. 4570-4575 ◽

Cited By ~ 87

Author(s):

Rong Zhang

Keyword(s):

Sea Ice ◽

Heat Transport ◽

Low Frequency ◽

Arctic Sea Ice ◽

The Arctic ◽

Sea Ice Extent ◽

Low Frequency Variability ◽

Sea Ice Decline ◽

Arctic Sea ◽

Arctic Sea Ice Extent

Satellite observations reveal a substantial decline in September Arctic sea ice extent since 1979, which has played a leading role in the observed recent Arctic surface warming and has often been attributed, in large part, to the increase in greenhouse gases. However, the most rapid decline occurred during the recent global warming hiatus period. Previous studies are often focused on a single mechanism for changes and variations of summer Arctic sea ice extent, and many are based on short observational records. The key players for summer Arctic sea ice extent variability at multidecadal/centennial time scales and their contributions to the observed summer Arctic sea ice decline are not well understood. Here a multiple regression model is developed for the first time, to the author’s knowledge, to provide a framework to quantify the contributions of three key predictors (Atlantic/Pacific heat transport into the Arctic, and Arctic Dipole) to the internal low-frequency variability of Summer Arctic sea ice extent, using a 3,600-y-long control climate model simulation. The results suggest that changes in these key predictors could have contributed substantially to the observed summer Arctic sea ice decline. If the ocean heat transport into the Arctic were to weaken in the near future due to internal variability, there might be a hiatus in the decline of September Arctic sea ice. The modeling results also suggest that at multidecadal/centennial time scales, variations in the atmosphere heat transport across the Arctic Circle are forced by anticorrelated variations in the Atlantic heat transport into the Arctic.

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Climate-driven benthic invertebrate activity and biogeochemical functioning across the Barents Sea polar front

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2019.0365 ◽

2020 ◽

Vol 378 (2181) ◽

pp. 20190365 ◽

Cited By ~ 3

Author(s):

Martin Solan ◽

Ellie R. Ward ◽

Christina L. Wood ◽

Adam J. Reed ◽

Laura J. Grange ◽

...

Keyword(s):

Sea Ice ◽

Ecosystem Functioning ◽

Barents Sea ◽

Benthic Invertebrate ◽

Polar Front ◽

The Arctic ◽

Nutrient Concentrations ◽

Sea Ice Extent ◽

Biological Communities ◽

The Barents Sea

Arctic marine ecosystems are undergoing rapid correction in response to multiple expressions of climate change, but the consequences of altered biodiversity for the sequestration, transformation and storage of nutrients are poorly constrained. Here, we determine the bioturbation activity of sediment-dwelling invertebrate communities over two consecutive summers that contrasted in sea-ice extent along a transect intersecting the polar front. We find a clear separation in community composition at the polar front that marks a transition in the type and amount of bioturbation activity, and associated nutrient concentrations, sufficient to distinguish a southern high from a northern low. While patterns in community structure reflect proximity to arctic versus boreal conditions, our observations strongly suggest that faunal activity is moderated by seasonal variations in sea ice extent that influence food supply to the benthos. Our observations help visualize how a climate-driven reorganization of the Barents Sea benthic ecosystem may be expressed, and emphasize the rapidity with which an entire region could experience a functional transformation. As strong benthic-pelagic coupling is typical across most parts of the Arctic shelf, the response of these ecosystems to a changing climate will have important ramifications for ecosystem functioning and the trophic structure of the entire food web. This article is part of the theme issue ‘The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

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Mechanisms influencing seasonal-to-interannual prediction skill of sea ice extent in the Arctic Ocean in MIROC

10.5194/tc-2017-122 ◽

2017 ◽

Author(s):

Jun Ono ◽

Hiroaki Tatebe ◽

Yoshiki Komuro ◽

Masato I. Nodzu ◽

Masayoshi Ishii

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Barents Sea ◽

Heat Content ◽

The Arctic ◽

Subsurface Water ◽

Lead Times ◽

Sea Ice Concentration ◽

Sea Ice Extent ◽

The Arctic Ocean

Abstract. To assess the skill of predictions of the seasonal-to-interannual detrended sea ice extent in the Arctic Ocean (SIEAO) and to clarify the underlying physical processes, we conducted ensemble hindcasts, started on January 1st, April 1st, July 1st, and October 1st for each year from 1980 to 2011, for lead times of up three years, using the Model for Interdisciplinary Research on Climate (MIROC) version 5 initialized with the observed atmosphere and ocean anomalies and sea ice concentration. Significant skill is found for the winter months: the December SIEAO can be predicted up to 1 year ahead. This skill is attributed to the subsurface ocean heat content originating in the North Atlantic. The subsurface water flows into the Barents Sea from spring to fall and emerges at the surface in winter by vertical mixing, and eventually affects the sea ice variability there. Meanwhile, the September SIEAO predictions are skillful for lead times of up to 3 months, due to the persistence of sea ice in the Beaufort, Chukchi, and East Siberian Seas initialized in July, as suggested by previous studies.

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Impact of wave-induced sea ice fragmentation on sea ice dynamics in the MIZ

10.5194/egusphere-egu2020-8657 ◽

2020 ◽

Author(s):

Guillaume Boutin ◽

Timothy Williams ◽

Pierre Rampal ◽

Einar Olason ◽

Camille Lique

Keyword(s):

Sea Ice ◽

Barents Sea ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Sea Ice Extent ◽

Ice Dynamics ◽

Sea Ice Dynamics ◽

Wave Induced ◽

The Impact

The decrease in Arctic sea ice extent is associated with an increase of the area where sea ice and open ocean interact, commonly referred to as the Marginal Ice Zone (MIZ). In this area, sea ice is particularly exposed to waves that can penetrate over tens to hundreds of kilometres into the ice cover. Waves are known to play a major role in the fragmentation of sea ice in the MIZ, and the interactions between wave-induced sea ice fragmentation and lateral melting have received particular attention in recent years. The impact of this fragmentation on sea ice dynamics, however, remains mostly unknown, although it is thought that fragmented sea ice experiences less resistance to deformation than pack ice. In this presentation, we will introduce a new coupled framework involving the spectral wave model WAVEWATCH III and the sea ice model neXtSIM, which includes a Maxwell-Elasto Brittle rheology. We use this coupled modelling system to investigate the potential impact of wave-induced sea ice fragmentation on sea ice dynamics. Focusing on the Barents Sea, we find that the decrease of the internal stress of sea ice resulting from its fragmentation by waves results in a more dynamical MIZ, in particular in areas where sea ice is compact. Sea ice drift is enhanced for both on-ice and off-ice wind conditions. Our results stress the importance of considering wave&#8211;sea-ice interactions for forecast applications. They also suggest that waves likely modulate the area of sea ice that is advected away from the pack by ocean (sub-)mesoscale eddies near the ice edge, potentially contributing to the observed past, current and future sea ice cover decline in the Arctic.&#160;

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