Extreme summer weather in northern mid-latitudes linked to a vanishing cryosphere

Journal name:
Nature Climate Change
Year published:
Published online

The past decade has seen an exceptional number of unprecedented summer extreme weather events1, 2, 3, 4 in northern mid-latitudes, along with record declines in both summer Arctic sea ice5, 6 and snow cover on high-latitude land7. The underlying mechanisms that link the shrinking cryosphere with summer extreme weather, however, remain unclear8, 9, 10, 11, 12. Here, we combine satellite observations of early summer snow cover and summer sea-ice extent13 with atmospheric reanalysis data14 to demonstrate associations between summer weather patterns in mid-latitudes and losses of snow and sea ice. Results suggest that the atmospheric circulation responds differently to changes in the ice and snow extents, with a stronger response to sea-ice loss, even though its reduction is half as large as that for the snow cover. Atmospheric changes associated with the combined snow/ice reductions reveal widespread upper-level height increases, weaker upper-level zonal winds at high latitudes, a more amplified upper-level pattern, and a general northward shift in the jet stream. More frequent extreme summer heat events over mid-latitude continents are linked with reduced sea ice and snow through these circulation changes.

At a glance


  1. SIE, SCE and Arctic Oscillation indices.
    Figure 1: SIE, SCE and Arctic Oscillation indices.

    a, Summer (JJA) Arctic SIE and early summer (May and June) Northern Hemisphere SCE. b, The third-order detrended summer SIE and early summer SCE indices (Methods) as well as the summer Arctic Oscillation index. Data span 1979–2012.

  2. Regressed height fields.
    Figure 2: Regressed height fields.

    ac, Linear regression of summer (JJA) geopotential height (m) at 900 (a), 500 (b) and 200hPa (c) on the detrended summer SIE index (reversed sign). df, The same as in ac but for the linear regression on the detrended early summer SCE index (reversed sign). gi, The same as in ac but for the linear regression on the combined SIE/SCE indices. jl, The same as in ac but for the linear regression on the inverted Arctic Oscillation index. The regression slope gives the geopotential height anomaly that occurs in association with 1.5millionkm2 SIE decline (in ac), 3millionkm2 SCE decline (in df), and the combined SIE/SCE declines (in gi). The yellow outline shows the continents and regions within black contours indicate that the regression exceeds the 95% confidence level.

  3. Regressed wind and height anomalies.
    Figure 3: Regressed wind and height anomalies.

    ad, Linear regressions of the summer zonal-mean zonal and meridional wind anomalies (vectors) and geopotential height anomalies (m, colour shading) at 500hPa on the sign-reversed detrended summer SIE index (a), early summer SCE index (note different vector scale; b), combined SIE/SCE indices (c), and inverted Arctic Oscillation index (d). The regression slope gives the geopotential height anomaly at 500hPa that occurs in association with 1.5millionkm2 SIE decline (a), 3millionkm2 SCE decline (b), and the combined SIE/SCE declines (c). Black contours indicate where height anomalies exceed the 95% confidence level.

  4. Regressed surface temperature and heat events.
    Figure 4: Regressed surface temperature and heat events.

    a,b, Linear regression of surface air temperature (a) and extreme heat events on the detrended combined SIE/SCE indices (reversed sign; b). The regression slope of extreme heat events is measured as the percentage relative to the summer extreme heat event climatology during 1979–2012. c,d, The same as in a,b but regressed onto the inverted Arctic Oscillation index. Black contours indicate regions where the anomalies exceed the 95% confidence level.


  1. Peterson, T. C., Hoerling, M. P., Stott, P. A. & Herring, S. C. (eds) Explaining extreme events of 2012 from a climate perspective. Bull. Am. Meteorol. Soc. 94, S1S74 (2013).
  2. Coumou, D. & Rahmstorf, S. A decade of weather extremes. Nature Clim. Change 2, 491496 (2012).
  3. Sutton, R. T. & Dong, B. Atlantic Ocean influence on a shift in European climate in the 1990s. Nature Geosci. 5, 788792 (2012).
  4. Seo, K-H., Son, J-H., Lee, S-E., Tomita, T. & Park, H-S. Mechanisms of an extraordinary East Asian summer monsoon event in July 2011. Geophys. Res. Lett. 39, L05704 (2012).
  5. Comiso, J. C. Large decadal decline of the Arctic multiyear ice cover. J. Clim. 25, 11761193 (2012).
  6. Stroeve, J. C. et al. The Arctic’s rapidly shrinking sea ice cover: a research synthesis. Climatic Change 110, 10051027 (2012).
  7. Derksen, C. & Brown, R. Spring snow cover extent reductions in the 2008–2012 period exceeding climate model projections. Geophys. Res. Lett. 39, L19504 (2012).
  8. Jaeger, E. B. & Seneviratne, S. I. Impact of soil moisture–atmosphere coupling on European climate extremes and trends in a regional climate model. Clim. Dynam. 36, 19191939 (2011).
  9. Overland, J. E., Francis, J. A., Hanna, E. & Wang, M. The recent shift in early summer Arctic atmospheric circulation. Geophys. Res. Lett. 39, L19804 (2012).
  10. Francis, J. A. & Vavrus, S. J. Evidence linking Arctic amplification to extreme weather in mid-latitudes. Geophys. Res. Lett. 39, L06801 (2012).
  11. Matsumura, S. & Yamazaki, K. Eurasian subarctic summer climate in response to anomalous snow cover. J. Clim. 25, 13051317 (2012).
  12. Tang, Q., Zhang, X., Yang, X. & Francis, J. A. Cold winter extremes in northern continents linked to Arctic sea ice loss. Environ. Res. Lett. 8, 014036 (2013).
  13. Cavalieri, D. J. & Parkinson, C. L. Arctic sea ice variability and trends, 1979–2010. Cryosphere 6, 881889 (2012).
  14. Dee, D. P. et al. The ERA-Interim reanalysis: configuration and performance of the data assimilation system. Q. J. R. Meteorol. Soc. 137, 553597 (2011).
  15. Polyakov, I. V. et al. Observationally based assessment of polar amplification of global warming. Geophys. Res. Lett. 29, 1878 (2002).
  16. Screen, J. A., Deser, C. & Simmonds, I. Local and remote controls on observed Arctic warming. Geophys. Res. Lett. 39, L10709 (2012).
  17. Serreze, M. C. & Francis, J. A. The Arctic amplification debate. Climatic Change 76, 241264 (2006).
  18. Screen, J. A. & Simmonds, I. The central role of diminishing sea ice in recent Arctic temperature amplification. Nature 464, 13341337 (2010).
  19. Porter, D. F., Cassano, J. J. & Serreze, M. C. Local and large-scale atmospheric responses to reduced Arctic sea ice and ocean warming in the WRF model. J. Geophys. Res. 117, D11115 (2012).
  20. Liu, J., Curry, J. A., Wang, H., Song, M. & Horton, R. M. Impact of declining Arctic sea ice on winter snowfall. Proc. Natl Acad. Sci. USA 109, 40744079 (2012).
  21. Petoukhov, V., Rahmstorf, S., Petri, S. & Schellnhuber, H. J. Quasiresonant amplification of planetary waves and recent northern hemisphere weather extremes. Proc. Natl Acad. Sci. USA 110, 53365341 (2013).
  22. Li, W., Li, L., Ting, M. & Liu, Y. Intensification of Northern Hemisphere subtropical highs in a warming climate. Nature Geosci. 5, 830834 (2012).
  23. Thompson, D. W. J. & Wallace, J. M. The Arctic Oscillation signature in the wintertime geopotential height and temperature fields. Geophys. Res. Lett. 25, 12971300 (1998).
  24. Stroeve, J. C. et al. Sea ice response to an extreme negative phase of the Arctic Oscillation during winter 2009/2010. Geophys. Res. Lett. 38, L02502 (2011).
  25. Ogi, M. & Wallace, J. M. The role of summer surface wind anomalies in the summer Arctic sea ice extent in 2010 and 2011. Geophys. Res. Lett. 39, L09704 (2012).
  26. Jaiser, R, Dethloff, K. & Handorf, D. Stratospheric response to Arctic sea ice retreat and associated planetary wave propagation changes. Tellus A 65, 111 (2013).
  27. Li, W., Li, L., Fu, R., Deng, Y. & Wang, H. Changes to the North Atlantic subtropical high and its role in the intensification of summer rainfall variability in the southeastern United States. J. Clim. 24, 14991506 (2011).
  28. Lau, W. K. M. & Kim, K-M. The 2010 Pakistan flood and Russian heat wave: teleconnection of hydrometeorological extremes. J. Hydrometeorol. 13, 392403 (2012).
  29. Weisberg, S. Applied Linear Regression 3rd edn (Wiley, 2005).
  30. Eisenman, I. Geographic muting of changes in the Arctic sea ice cover. Geophys. Res. Lett. 37, L16501 (2010).

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  1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

    • Qiuhong Tang &
    • Xuejun Zhang
  2. University of Chinese Academy of Sciences, Beijing 100049, China

    • Xuejun Zhang
  3. Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey 08901, USA

    • Jennifer A. Francis


Q.T. and J.A.F. designed the study. Q.T., X.Z. and J.A.F. conducted the analysis and all of the authors contributed to the paper writing.

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The authors declare no competing financial interests.

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