Variable Freshwater Input to the Arctic Ocean During the Holocene: Implications for Large-Scale Ocean-Sea Ice Dynamics as Simulated by a Circulation Model

Soviet plans to divert water from rivers flowing into the Arctic Ocean have led to research into the impact of a reduction in discharge on Arctic sea ice. We consider the mechanisms by which discharge reductions might affect sea-ice cover and then test various hypotheses related to these mechanisms. We find several large areas over which sea-ice concentration correlates significantly with variations in river discharge, supporting two particular hypotheses. The first hypothesis concerns the area where the initial impacts are likely to which is the Kara Sea. Reduced riverflow is associated occur, with decreased sea-ice concentration in October, at the time of ice formation. This is believed to be the result of decreased freshening of the surface layer. The second hypothesis concerns possible effects on the large-scale current system of the Arctic Ocean and, in particular, on the inflow of Atlantic and Pacific water. These effects occur as a result of changes in the strength of northward-flowing gradient currents associated with variations in river discharge. Although it is still not certain that substantial transfers of riverflow will take place, it is concluded that the possibility of significant cryospheric effects and, hence, large-scale climate impact should not be neglected.

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Evolution of the seasonal temperature cycle in a transient Holocene simulation: orbital forcing and sea-ice

Climate of the Past Discussions ◽

10.5194/cpd-7-463-2011 ◽

2011 ◽

Vol 7 (1) ◽

pp. 463-483 ◽

Cited By ~ 2

Author(s):

N. Fischer ◽

J. H. Jungclaus

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

The Arctic ◽

Northern Europe ◽

Temperature Cycle ◽

Surface Model ◽

Seasonal Temperature ◽

Ice Dynamics ◽

Summer Insolation ◽

The Arctic Ocean

Abstract. Changes in the Earth's orbit lead to changes in the seasonal and meridional distribution of insolation. We quantify the influence of orbitally induced changes on the seasonal temperature cycle in a transient simulation of the last 6000 years – from the mid-Holocene to today – using a coupled atmosphere-ocean general circulation model (ECHAM5/MPI-OM) including a land surface model (JSBACH). The seasonal temperature cycle responds directly to the insolation changes almost everywhere. In the Northern Hemisphere, its amplitude decreases according to an increase in winter insolation and a decrease in summer insolation. In the Southern Hemisphere, the opposite is true. Over the Arctic Ocean, however, decreasing summer insolation leads to an increase of sea-ice cover. The insulating effect of sea ice between the ocean and the atmosphere favors more continental conditions over the Arctic Ocean in winter, resulting in strongly decreasing temperatures. Consequently, there are two competing effects: the direct response to insolation changes and a sea-ice dynamics feedback. The sea-ice feedback is stronger, and thus an increase in the amplitude of the seasonal cycle over the Arctic Ocean occurs. This increase is strongest over the Barents Shelf and influences the temperature response over northern Europe. We compare our modelled seasonal temperatures over Europe to paleo reconstructions. We find better agreements in winter temperatures than in summer temperatures and better agreements in northern Europe than in southern Europe, since the model does not reproduce the southern European Holocene summer cooling inferred from the paleo data. The temperature reconstructions for northern Europe support the notion of the influence of the sea-ice effect on the evolution of the seasonal temperature cycle.

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Climate changes modulated the history of Arctic iodine during the Last Glacial Cycle

Nature Communications ◽

10.1038/s41467-021-27642-5 ◽

2022 ◽

Vol 13 (1) ◽

Author(s):

Juan Pablo Corella ◽

Niccolo Maffezzoli ◽

Andrea Spolaor ◽

Paul Vallelonga ◽

Carlos A. Cuevas ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Radiative Forcing ◽

Climate Changes ◽

Ice Cores ◽

The Arctic ◽

Glacial Cycle ◽

Ice Dynamics ◽

Sea Ice Dynamics ◽

Ultrafine Aerosol

AbstractIodine has a significant impact on promoting the formation of new ultrafine aerosol particles and accelerating tropospheric ozone loss, thereby affecting radiative forcing and climate. Therefore, understanding the long-term natural evolution of iodine, and its coupling with climate variability, is key to adequately assess its effect on climate on centennial to millennial timescales. Here, using two Greenland ice cores (NEEM and RECAP), we report the Arctic iodine variability during the last 127,000 years. We find the highest and lowest iodine levels recorded during interglacial and glacial periods, respectively, modulated by ocean bioproductivity and sea ice dynamics. Our sub-decadal resolution measurements reveal that high frequency iodine emission variability occurred in pace with Dansgaard/Oeschger events, highlighting the rapid Arctic ocean-ice-atmosphere iodine exchange response to abrupt climate changes. Finally, we discuss if iodine levels during past warmer-than-present climate phases can serve as analogues of future scenarios under an expected ice-free Arctic Ocean. We argue that the combination of natural biogenic ocean iodine release (boosted by ongoing Arctic warming and sea ice retreat) and anthropogenic ozone-induced iodine emissions may lead to a near future scenario with the highest iodine levels of the last 127,000 years.

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Erratum to: “Reproduction of the Large-Scale State of Water and Sea Ice in the Arctic Ocean in 1948–2002: Part I. Numerical Model”

Izvestiya Atmospheric and Oceanic Physics ◽

10.1134/s0001433811690016 ◽

2011 ◽

Vol 47 (6) ◽

pp. 794-794

Author(s):

S. N. Moshonkin ◽

G. V. Alekseev ◽

N. A. Dianskii ◽

A. V. Gusev ◽

V. B. Zalesny

Keyword(s):

Numerical Model ◽

Sea Ice ◽

Arctic Ocean ◽

Large Scale ◽

The Arctic ◽

State Of Water ◽

The Arctic Ocean

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Reproduction of the large-scale state of water and sea ice in the Arctic Ocean in 1948–2002: Part I. Numerical model

Izvestiya Atmospheric and Oceanic Physics ◽

10.1134/s0001433809030098 ◽

2009 ◽

Vol 45 (3) ◽

pp. 357-371 ◽

Cited By ~ 23

Author(s):

N. G. Yakovlev

Keyword(s):

Numerical Model ◽

Sea Ice ◽

Arctic Ocean ◽

Large Scale ◽

The Arctic ◽

State Of Water ◽

The Arctic Ocean

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Arctic Ocean sea ice snow depth evaluation and bias sensitivity in CCSM

The Cryosphere Discussions ◽

10.5194/tcd-7-1495-2013 ◽

2013 ◽

Vol 7 (2) ◽

pp. 1495-1532 ◽

Cited By ~ 6

Author(s):

B. A. Blazey ◽

M. M. Holland ◽

E. C. Hunke

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Large Scale ◽

System Model ◽

Arctic Climate ◽

The Arctic ◽

Blowing Snow ◽

Climate System Model ◽

The Arctic Ocean ◽

Ice Conditions

Abstract. Sea ice cover in the Arctic Ocean is a continued focus of attention. This study assesses the capability of hindcast simulations of the Community Climate System Model (CCSM) to reproduce observed snow depths and densities overlying the Arctic Ocean sea ice. The model is evaluated using measurements provided by historic Russian polar drift stations. Following the identification of seasonal biases produced in the simulations, the thermodynamic transfer through the snow – ice column is perturbed to determine model sensitivity to these biases. This study concludes that perturbations on the order of the observed biases result in modification of the annual mean conductive flux of 0.5 W m−2 relative to an unmodified simulation. The results suggest that the ice has a complex response to snow characteristics, with ice of different thicknesses producing distinct reactions. Consequently, we suggest that the inclusion of additional snow evolution processes such as blowing snow, densification, and seasonal changes in snow conductivity in sea ice models would increase the fidelity of the model with respect to the physical system. Moreover, our results suggest that simulated high latitude precipitation biases have important effects on the simulated ice conditions, resulting in impacts on the Arctic climate in general in large-scale climate.

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Freshwater pulses in the eastern Arctic Ocean during Saalian and Early Weichselian ice-sheet collapse

Quaternary Research ◽

10.1016/j.yqres.2003.07.008 ◽

2003 ◽

Vol 60 (3) ◽

pp. 243-251 ◽

Cited By ~ 26

Author(s):

Jochen Knies ◽

Christoph Vogt

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Large Scale ◽

Barents Sea ◽

The Arctic ◽

Fram Strait ◽

Nordic Seas ◽

The Arctic Ocean ◽

Transpolar Drift ◽

Mis 5

AbstractImproved multiparameter records from the northern Barents Sea margin show two prominent freshwater pulses into the Arctic Ocean during MIS 5 that significantly disturbed the regional oceanic regime and probably affected global climate. Both pulses are associated with major iceberg-rafted debris (IRD) events, revealing intensive iceberg/sea ice melting. The older meltwater pulse occurred near the MIS 5/6 boundary (∼131,000 yr ago); its ∼2000 year duration and high IRD input accompanied by high illite content suggest a collapse of large-scale Saalian Glaciation in the Arctic Ocean. Movement of this meltwater with the Transpolar Drift current into the Fram Strait probably promoted freshening of Nordic Seas surface water, which may have increased sea-ice formation and significantly reduced deep-water formation. A second pulse of freshwater occurred within MIS 5a (∼77,000 yr ago); its high smectite content and relatively short duration is possibly consistent with sudden discharge of Early Weichselian ice-dammed lakes in northern Siberia as suggested by terrestrial glacial geologic data. The influence of this MIS 5a meltwater pulse has been observed at a number of sites along the Transpolar Drift, through Fram Strait, and into the Nordic Seas; it may well have been a trigger for the North Atlantic cooling event C20.

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A satellite-based estimate of combustion aerosol cloud microphysical effects over the Arctic Ocean

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-14949-2018 ◽

2018 ◽

Vol 18 (20) ◽

pp. 14949-14964 ◽

Cited By ~ 6

Author(s):

Lauren M. Zamora ◽

Ralph A. Kahn ◽

Klaus B. Huebert ◽

Andreas Stohl ◽

Sabine Eckhardt

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Large Scale ◽

Transport Model ◽

The Arctic ◽

Energy Budgets ◽

Precipitation Frequency ◽

Aerosol Cloud ◽

The Arctic Ocean ◽

Combustion Aerosols

Abstract. Climate predictions for the rapidly changing Arctic are highly uncertain, largely due to a poor understanding of the processes driving cloud properties. In particular, cloud fraction (CF) and cloud phase (CP) have major impacts on energy budgets, but are poorly represented in most models, often because of uncertainties in aerosol–cloud interactions. Here, we use over 10 million satellite observations coupled with aerosol transport model simulations to quantify large-scale microphysical effects of aerosols on CF and CP over the Arctic Ocean during polar night, when direct and semi-direct aerosol effects are minimal. Combustion aerosols over sea ice are associated with very large (∼10 W m−2) differences in longwave cloud radiative effects at the sea ice surface. However, co-varying meteorological changes on factors such as CF likely explain the majority of this signal. For example, combustion aerosols explain at most 40 % of the CF differences between the full dataset and the clean-condition subset, compared to between 57 % and 91 % of the differences that can be predicted by co-varying meteorology. After normalizing for meteorological regime, aerosol microphysical effects have small but significant impacts on CF, CP, and precipitation frequency on an Arctic-wide scale. These effects indicate that dominant aerosol–cloud microphysical mechanisms are related to the relative fraction of liquid-containing clouds, with implications for a warming Arctic.

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