Atmospheric forcing dominates winter Barents-Kara sea ice variability on interannual to decadal time scales

The last two decades have seen a dramatic decline and strong year-to-year variability in Arctic winter sea ice, especially in the Barents-Kara Sea (BKS), changes that have been linked to extreme midlatitude weather and climate. It has been suggested that these changes in winter sea ice arise largely from a combined effect of oceanic and atmospheric processes, but the relative importance of these processes is not well established. Here, we explore the role of atmospheric circulation patterns on BKS winter sea ice variability and trends using observations and climate model simulations. We find that BKS winter sea ice variability is primarily driven by a strong anticyclonic anomaly over the region, which explains more than 50% of the interannual variability in BKS sea-ice concentration (SIC). Recent intensification of the anticyclonic anomaly has warmed and moistened the lower atmosphere in the BKS by poleward transport of moist-static energy and local processes, resulting in an increase in downwelling longwave radiation. Our results demonstrate that the observed BKS winter sea-ice variability is primarily driven by atmospheric, rather than oceanic, processes and suggest a persistent role of atmospheric forcing in future Arctic winter sea ice loss.

[1]  Sukyoung Lee,et al.  The Role of Planetary-scale Eddies on the Recent Isentropic Slope Trend during Boreal Winter , 2021, Journal of the Atmospheric Sciences.

[2]  Zhenya Song,et al.  The poleward enhanced Arctic Ocean cooling machine in a warming climate , 2021, Nature Communications.

[3]  J. Welker,et al.  Arctic sea-ice loss fuels extreme European snowfall , 2021, Nature Geoscience.

[4]  Francis Codron,et al.  Acceleration of western Arctic sea ice loss linked to the Pacific North American pattern , 2021, Nature Communications.

[5]  S. Østerhus,et al.  Increased ocean heat transport into the Nordic Seas and Arctic Ocean over the period 1993–2016 , 2020, Nature Climate Change.

[6]  J. Screen,et al.  Weakened evidence for mid-latitude impacts of Arctic warming , 2020, Nature Climate Change.

[7]  M. Holland,et al.  Extremes become routine in an emerging new Arctic , 2020, Nature Climate Change.

[8]  J. Thepaut,et al.  The ERA5 global reanalysis , 2020, Quarterly Journal of the Royal Meteorological Society.

[9]  R. Kwok,et al.  Divergent consensuses on Arctic amplification influence on midlatitude severe winter weather , 2019, Nature Climate Change.

[10]  J. Screen,et al.  Is sea-ice-driven Eurasian cooling too weak in models? , 2019, Nature Climate Change.

[11]  J. Screen,et al.  Minimal influence of reduced Arctic sea ice on coincident cold winters in mid-latitudes , 2019, Nature Climate Change.

[12]  M. Balmaseda,et al.  The ECMWF operational ensemble reanalysis–analysis system for ocean and sea ice: a description of the system and assessment , 2019, Ocean Science.

[13]  D. Notz,et al.  Arctic sea-ice variability is primarily driven by atmospheric temperature fluctuations , 2019, Nature Geoscience.

[14]  M. Kimoto,et al.  A reconciled estimate of the influence of Arctic sea-ice loss on recent Eurasian cooling , 2019, Nature Climate Change.

[15]  H. Goosse,et al.  An assessment of ten ocean reanalyses in the polar regions , 2019, Climate Dynamics.

[16]  D. Schröder,et al.  New insight from CryoSat-2 sea ice thickness for sea ice modelling , 2018, The Cryosphere.

[17]  R. Ingvaldsen,et al.  Arctic warming hotspot in the northern Barents Sea linked to declining sea-ice import , 2018, Nature Climate Change.

[18]  H. Wernli,et al.  Role of polar anticyclones and mid-latitude cyclones for Arctic summertime sea-ice melting , 2018, Nature Geoscience.

[19]  Mark D. Zelinka,et al.  Clearing clouds of uncertainty , 2017 .

[20]  Wei Liu,et al.  Arctic sea-ice decline weakens the Atlantic Meridional Overturning Circulation , 2017 .

[21]  Torsten Kanzow,et al.  Greater role for Atlantic inflows on sea-ice loss in the Eurasian Basin of the Arctic Ocean , 2017, Science.

[22]  T. Knutson,et al.  On the discrepancy between observed and CMIP5 multi-model simulated Barents Sea winter sea ice decline , 2017, Nature Communications.

[23]  Axel Schweiger,et al.  Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice , 2017 .

[24]  J. Fyfe,et al.  Twenty-five winters of unexpected Eurasian cooling unlikely due to Arctic sea-ice loss , 2016 .

[25]  T. Shepherd,et al.  Nonlinear response of mid-latitude weather to the changing Arctic , 2016 .

[26]  Mark D. Zelinka,et al.  Evidence for climate change in the satellite cloud record , 2016, Nature.

[27]  Veronika Eyring,et al.  Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design and organization , 2015 .

[28]  M. Aschan,et al.  Recent warming leads to a rapid borealization of fish communities in the Arctic , 2015 .

[29]  H. Bryden,et al.  Observing the Atlantic Meridional Overturning Circulation yields a decade of inevitable surprises , 2015, Science.

[30]  Rong‐Hua Zhang Mechanisms for low-frequency variability of summer Arctic sea ice extent , 2015, Proceedings of the National Academy of Sciences.

[31]  M. Kimoto,et al.  Robust Arctic sea-ice influence on the frequent Eurasian cold winters in past decades , 2014 .

[32]  Timo Vihma,et al.  Effects of Arctic Sea Ice Decline on Weather and Climate: A Review , 2014, Surveys in Geophysics.

[33]  T. Mauritsen,et al.  Arctic amplification dominated by temperature feedbacks in contemporary climate models , 2014 .

[34]  Camille Li,et al.  THE ROLE OF THE BARENTS SEA IN THE ARCTIC CLIMATE SYSTEM , 2013 .

[35]  Mark Hebblewhite,et al.  Ecological Consequences of Sea-Ice Decline , 2013, Science.

[36]  Marie-Luise Kapsch,et al.  Springtime atmospheric energy transport and the control of Arctic summer sea-ice extent , 2013 .

[37]  M. Latif,et al.  North Atlantic Ocean control on surface heat flux on multidecadal timescales , 2013, Nature.

[38]  S. Bony,et al.  Climate change projections using the IPSL-CM5 Earth System Model: from CMIP3 to CMIP5 , 2013, Climate Dynamics.

[39]  J. Thepaut,et al.  The ERA‐Interim reanalysis: configuration and performance of the data assimilation system , 2011 .

[40]  Thomas M. Marchitto,et al.  Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water , 2011, Science.

[41]  Francis Codron Ekman heat transport for slab oceans , 2011, Climate Dynamics.

[42]  I. Simmonds,et al.  The central role of diminishing sea ice in recent Arctic temperature amplification , 2010, Nature.

[43]  E. Källén,et al.  Vertical structure of recent Arctic warming , 2008, Nature.

[44]  S. Bony,et al.  The LMDZ4 general circulation model: climate performance and sensitivity to parametrized physics with emphasis on tropical convection , 2006 .