Probabilistic forecasting of the Arctic sea ice edge with contour modeling

AbstractIn this study the impact of extreme cyclones on Arctic sea ice in summer is investigated. Examined in particular are relative thermodynamic and dynamic contributions to sea ice volume budgets in the vicinity of Arctic summer cyclones in 2012 and 2016. Results from this investigation illustrate sea ice loss in the vicinity of the cyclone trajectories during each year were associated with different dominant processes: thermodynamic (melting) in the Pacific sector of the Arctic in 2012, and both thermodynamic and dynamic processes in the Pacific sector of the Arctic in 2016. Comparison of both years further suggests that the Arctic minimum sea ice extent is influenced by not only the strength of the cyclone, but also by the timing and location relative to the sea ice edge. Located near the sea ice edge in early August in 2012, and over the central Arctic later in August in 2016, extreme cyclones contributed to comparable sea ice area (SIA) loss, yet enhanced sea ice volume loss in 2012 relative to 2016.Central to a characterization of extreme cyclone impacts on Arctic sea ice from the perspective of thermodynamic and dynamic processes, we present an index describing relative thermodynamic and dynamic contributions to sea ice volume changes. This index helps to quantify and improve our understanding of initial sea ice state and dynamical responses to cyclones in a rapidly warming Arctic, with implications for seasonal ice forecasting, marine navigation, coastal community infrastructure and designation of protected and ecologically sensitive marine zones.

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Predictability of the Arctic sea ice edge

Geophysical Research Letters ◽

10.1002/2015gl067232 ◽

2016 ◽

Vol 43 (4) ◽

pp. 1642-1650 ◽

Cited By ~ 43

Author(s):

H. F. Goessling ◽

S. Tietsche ◽

J. J. Day ◽

E. Hawkins ◽

T. Jung

Keyword(s):

Sea Ice ◽

Arctic Sea Ice ◽

The Arctic ◽

Arctic Sea ◽

Ice Edge ◽

Sea Ice Edge

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Summer predictions of Arctic sea ice edge in multi-model seasonal re-forecasts

Climate Dynamics ◽

10.1007/s00382-020-05273-8 ◽

2020 ◽

Vol 54 (11-12) ◽

pp. 5013-5029

Author(s):

Lauriane Batté ◽

Ilona Välisuo ◽

Matthieu Chevallier ◽

Juan C. Acosta Navarro ◽

Pablo Ortega ◽

...

Keyword(s):

Sea Ice ◽

Arctic Sea Ice ◽

Arctic Sea ◽

Ice Edge ◽

Sea Ice Edge

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Near-ubiquity of ice-edge blooms in the Arctic

Biogeosciences ◽

10.5194/bg-8-515-2011 ◽

2011 ◽

Vol 8 (2) ◽

pp. 515-524 ◽

Cited By ~ 124

Author(s):

M. Perrette ◽

A. Yool ◽

G. D. Quartly ◽

E. E. Popova

Keyword(s):

Sea Ice ◽

Late Summer ◽

Arctic Sea Ice ◽

Trophic Levels ◽

The Arctic ◽

Fish Stocks ◽

Arctic Sea ◽

Ice Retreat ◽

Ice Edge ◽

Adequate Data

Abstract. Ice-edge blooms are significant features of Arctic primary production, yet have received relatively little attention. Here we combine satellite ocean colour and sea-ice data in a pan-Arctic study. Ice-edge blooms occur in all seasonally ice-covered areas and from spring to late summer, being observed in 77–89% of locations for which adequate data exist, and usually peaking within 20 days of ice retreat. They sometimes form long belts along the ice-edge (greater than 100 km), although smaller structures were also found. The bloom peak is on average more than 1 mg m−3, with major blooms more than 10 mg m−3, and is usually located close to the ice-edge, though not always. Some propagate behind the receding ice-edge over hundreds of kilometres and over several months, while others remain stationary. The strong connection between ice retreat and productivity suggests that the ongoing changes in Arctic sea-ice may have a significant impact on higher trophic levels and local fish stocks.

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A spatial evaluation of Arctic sea ice and regional limitations in CMIP6 historical simulations

Journal of Climate ◽

10.1175/jcli-d-20-0491.1 ◽

2021 ◽

pp. 1-54

Author(s):

Matthew Watts ◽

Wieslaw Maslowski ◽

Younjoo J. Lee ◽

Jaclyn Clement Kinney ◽

Robert Osinski

Keyword(s):

Spatial Distribution ◽

Spatial Analysis ◽

Sea Ice ◽

Arctic Sea Ice ◽

Ocean Modeling ◽

The Arctic ◽

Brier Score ◽

Wide Range ◽

Arctic Sea ◽

Ice Edge

AbstractThe Arctic sea ice response to a warming climate is assessed in a subset of models participating in Phase 6 of the Coupled Model Intercomparison Project (CMIP6), using several metrics in comparison with satellite observations and results from the Pan-Arctic Ice Ocean Modeling and Assimilation System and the Regional Arctic System Model. Our study examines the historical representation of sea ice extent, volume, and thickness using spatial analysis metrics, such as the integrated ice-edge error, Brier score, and Spatial Probability Score. We find that the CMIP6 multi-model mean captures the mean annual cycle and 1979-2014 sea ice trends remarkably well. However, individual models experience a wide range of uncertainty in the spatial distribution of sea ice when compared against satellite measurements and reanalysis data. Our metrics expose common and individual regional model biases, which sea ice temporal analyses alone do not capture. We identify large ice edge and ice thickness errors in Arctic sub-regions, implying possible model specific limitations in or lack of representation of some key physical processes. We postulate that many of them could be related to the oceanic forcing, especially in the marginal and shelf seas, where seasonal sea ice changes are not adequately simulated. We therefore conclude that an individual model’s ability to represent the observed/reanalysis spatial distribution still remains a challenge. We propose the spatial analysis metrics as useful tools to diagnose model limitations, narrow down possible processes affecting them, and guide future model improvements critical to the representation and projections of Arctic climate change.

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Near-ubiquity of ice-edge blooms in the Arctic

Biogeosciences Discussions ◽

10.5194/bgd-7-8123-2010 ◽

2010 ◽

Vol 7 (6) ◽

pp. 8123-8142 ◽

Cited By ~ 5

Author(s):

M. Perrette ◽

A. Yool ◽

G. D. Quartly ◽

E. E. Popova

Keyword(s):

Sea Ice ◽

Late Summer ◽

Arctic Sea Ice ◽

Trophic Levels ◽

The Arctic ◽

Fish Stocks ◽

Arctic Sea ◽

Ice Retreat ◽

Ice Edge ◽

Adequate Data

Abstract. Ice-edge blooms are significant features of Arctic primary production, yet have received relatively little attention. Here we combine satellite ocean colour and sea-ice data in a pan-Arctic study. Ice-edge blooms occur in all seasonally ice-covered areas and from spring to late summer, being observed in 77–89% of locations for which adequate data exist, and usually peaking within 20 days of ice retreat. They sometimes form long belts along the Ice-edge (greater than 100 km), although smaller structures were also found. The bloom peak is on average more than 1 mg m−3, with major blooms more than 10 mg m−3, and is usually located close to the ice-edge, though not always. Some propagate behind the receding ice-edge over hundreds of kilometres and over several months, while others remain stationary. The strong connection between ice retreat and productivity suggests that the ongoing changes in Arctic sea-ice may have a significant impact on higher trophic levels and local fish stocks.

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Phytoplankton and dimethylsulfide dynamics at two contrasting Arctic ice edges

Biogeosciences ◽

10.5194/bg-17-1557-2020 ◽

2020 ◽

Vol 17 (6) ◽

pp. 1557-1581 ◽

Cited By ~ 1

Author(s):

Martine Lizotte ◽

Maurice Levasseur ◽

Virginie Galindo ◽

Margaux Gourdal ◽

Michel Gosselin ◽

...

Keyword(s):

Sea Ice ◽

Surface Waters ◽

Arctic Sea Ice ◽

The Arctic ◽

Chl A ◽

Melt Pond ◽

Nares Strait ◽

Arctic Sea ◽

Ice Edge ◽

Methylated Sulfur Compounds

Abstract. Arctic sea ice is retreating and thinning and its rate of decline has steepened in the last decades. While phytoplankton blooms are known to seasonally propagate along the ice edge as it recedes from spring to summer, the substitution of thick multiyear ice (MYI) with thinner, ponded first-year ice (FYI) represents an unequal exchange when considering the roles sea ice plays in the ecology and climate of the Arctic. Consequences of this shifting sea ice on the phenology of phytoplankton and the associated cycling of the climate-relevant gas dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) remain ill constrained. In July–August 2014, two contrasting ice edges in the Canadian High Arctic were explored: a FYI-dominated ice edge in Barrow Strait and a MYI-dominated ice edge in Nares Strait. Our results reveal two distinct planktonic systems and associated DMS dynamics in connection to these diverging ice types. The surface waters exiting the ponded FYI in Barrow Strait were characterized by moderate chlorophyll a (Chl a, <2.1 µg L−1) as well as high DMSP (115 nmol L−1) and DMS (12 nmol L−1), suggesting that a bloom had already started to develop under the markedly melt-pond-covered (ca. 40 %) FYI. Heightened DMS concentrations at the FYI edge were strongly related to ice-associated seeding of DMS in surface waters and haline-driven stratification linked to ice melt (Spearman's rank correlation between DMS and salinity, rs=-0.91, p<0.001, n=20). However, surface waters exiting the MYI edge at the head of Nares Strait were characterized by low concentrations of Chl a (<0.5 µg L−1), DMSP (<16 nmol L−1), and DMS (<0.4 nmol L−1), despite the nutrient-replete conditions characterizing the surface waters. The increase in autotrophic biomass and methylated sulfur compounds took place several kilometers (ca. 100 km) away from the MYI edge, suggesting the requisite for ice-free, light-sufficient conditions for a phytoplankton bloom to fully develop and for sulfur compound dynamics to follow and expand. In light of the ongoing and projected climate-driven changes to Arctic sea ice, results from this study suggest that the early onset of autotrophic blooms under thinner, melt-pond-covered ice may have vast implications for the timing and magnitude of DMS pulses in the Arctic.

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Prévoir les variations saisonnières de la glace de mer arctique et leurs impacts sur le climat

La Météorologie ◽

10.37053/lameteorologie-2020-0089 ◽

2020 ◽

pp. 024

Author(s):

Rym Msadek ◽

Gilles Garric ◽

Sara Fleury ◽

Florent Garnier ◽

Lauriane Batté ◽

...

Keyword(s):

Sea Ice ◽

Arctic Region ◽

Arctic Sea Ice ◽

Climate Impacts ◽

The Arctic ◽

Recent Effort ◽

Sea Ice Thickness ◽

Arctic Sea ◽

Ice Conditions ◽

Upper Level

L'Arctique est la région du globe qui s'est réchauffée le plus vite au cours des trente dernières années, avec une augmentation de la température de surface environ deux fois plus rapide que pour la moyenne globale. Le déclin de la banquise arctique observé depuis le début de l'ère satellitaire et attribué principalement à l'augmentation de la concentration des gaz à effet de serre aurait joué un rôle important dans cette amplification des températures au pôle. Cette fonte importante des glaces arctiques, qui devrait s'accélérer dans les décennies à venir, pourrait modifier les vents en haute altitude et potentiellement avoir un impact sur le climat des moyennes latitudes. L'étendue de la banquise arctique varie considérablement d'une saison à l'autre, d'une année à l'autre, d'une décennie à l'autre. Améliorer notre capacité à prévoir ces variations nécessite de comprendre, observer et modéliser les interactions entre la banquise et les autres composantes du système Terre, telles que l'océan, l'atmosphère ou la biosphère, à différentes échelles de temps. La réalisation de prévisions saisonnières de la banquise arctique est très récente comparée aux prévisions du temps ou aux prévisions saisonnières de paramètres météorologiques (température, précipitation). Les résultats ayant émergé au cours des dix dernières années mettent en évidence l'importance des observations de l'épaisseur de la glace de mer pour prévoir l'évolution de la banquise estivale plusieurs mois à l'avance. Surface temperatures over the Arctic region have been increasing twice as fast as global mean temperatures, a phenomenon known as arctic amplification. One main contributor to this polar warming is the large decline of Arctic sea ice observed since the beginning of satellite observations, which has been attributed to the increase of greenhouse gases. The acceleration of Arctic sea ice loss that is projected for the coming decades could modify the upper level atmospheric circulation yielding climate impacts up to the mid-latitudes. There is considerable variability in the spatial extent of ice cover on seasonal, interannual and decadal time scales. Better understanding, observing and modelling the interactions between sea ice and the other components of the climate system is key for improved predictions of Arctic sea ice in the future. Running operational-like seasonal predictions of Arctic sea ice is a quite recent effort compared to weather predictions or seasonal predictions of atmospheric fields like temperature or precipitation. Recent results stress the importance of sea ice thickness observations to improve seasonal predictions of Arctic sea ice conditions during summer.

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