Nonlinear response of mid-latitude weather to the changing Arctic

Abstract

Are continuing changes in the Arctic influencing wind patterns and the occurrence of extreme weather events in northern mid-latitudes? The chaotic nature of atmospheric circulation precludes easy answers. The topic is a major science challenge, as continued Arctic temperature increases are an inevitable aspect of anthropogenic climate change. We propose a perspective that rejects simple cause-and-effect pathways and notes diagnostic challenges in interpreting atmospheric dynamics. We present a way forward based on understanding multiple processes that lead to uncertainties in Arctic and mid-latitude weather and climate linkages. We emphasize community coordination for both scientific progress and communication to a broader public.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Different configurations of the tropospheric polar vortex.
Figure 2: A complex web of pathways summarizing examples of potential mechanisms that contribute to more frequent amplified flow and more persistent weather patterns in mid-latitudes.
Figure 3: Global air temperatures anomalies (°C) for January 2016.
Figure 4: State dependence of the atmospheric response to Arctic sea ice loss.
Figure 5: Current state of the science for selected linkages.

References

  1. 1

    Serreze, M., Barrett, A., Stroeve, J., Kindig, D. & Holland, M. The emergence of surface-based Arctic amplification. Cryosphere 3, 11–19 (2009).

    Article  Google Scholar 

  2. 2

    Overland, J. E., Wang, M., Walsh, J. E. & Stroeve, J. C. Future Arctic climate changes: adaptation and mitigation timescales. Earth's Future 2, 68–74 (2014).

    Article  Google Scholar 

  3. 3

    Francis, J. A. & Vavrus, S. J. Evidence for a wavier jet stream in response to rapid Arctic warming. Environ. Res. Lett. 10, 014005 (2015).

    Article  Google Scholar 

  4. 4

    Wallace, J. M., Held, I. M., Thompson, D. W. J., Trenberth, K. E. & Walsh, J. E. Global warming and winter weather. Science 343, 729–730 (2014).

    Article  CAS  Google Scholar 

  5. 5

    Barnes, E. A. & Screen, J. A. The impact of Arctic warming on the midlatitude jet- stream: can it? Has it? Will it? WIREs Clim. Change 6, 277–286 (2015).

    Article  Google Scholar 

  6. 6

    Sun, L., Perlwitz, J. & Hoerling, M. What caused the recent “Warm Arctic, Cold Continents” trend pattern in winter temperatures? Geophys. Res. Lett. 43, 5345–5352 (2016).

    Article  Google Scholar 

  7. 7

    Overland, J. E. et al. The melting Arctic and mid-latitude weather patterns: are they connected? J. Clim. 28, 7917–7932 (2015).

    Article  Google Scholar 

  8. 8

    Petoukhov, V. & Semenov, V. A. A link between reduced Barents-Kara sea ice and cold winter extremes over northern continents. J. Geophys. Res. 115, D21111 (2010).

    Article  Google Scholar 

  9. 9

    Peings, Y. & Magnusdottir, G. Response of the wintertime Northern Hemisphere atmospheric circulation to current and projected Arctic sea ice decline. J. Clim. 27, 244–264 (2014).

    Article  Google Scholar 

  10. 10

    Semenov, V. A. & Latif, M. Nonlinear winter atmospheric circulation response to Arctic sea ice concentration anomalies for different periods during 1966–2012. Environ. Res. Lett. 10, 054020 (2015).

    Article  Google Scholar 

  11. 11

    Screen, J. A. & Simmonds, I. Exploring links between Arctic amplification and mid-latitude weather. Geophys. Res. Lett. 40, 959–964 (2013).

    Article  Google Scholar 

  12. 12

    Barnes, E. A. Revisiting the evidence linking Arctic amplification to extreme weather in midlatitudes. Geophys. Res. Lett. 40, 4734–4739 (2013).

    Article  Google Scholar 

  13. 13

    Orsolini, Y. J., Senan, R., Benestad, R. E. & Melsom, A. Autumn atmospheric response to the 2007 low Arctic sea ice extent in coupled ocean–atmosphere hindcasts. Clim. Dynam. 38, 2437–2448 (2012).

    Article  Google Scholar 

  14. 14

    Overland, J. E. et al. Surface Air Temperature (Arctic Report Card 2015, 2015); http://www.arctic.noaa.gov/report15/air_temperature.html.

    Google Scholar 

  15. 15

    Screen, J. A. & Simmonds, I. The central role of diminishing sea ice in recent Arctic temperature amplification. Nature 464, 1334–1337 (2010).

    CAS  Google Scholar 

  16. 16

    Coumou, D., Lehmann, J. & Beckmann, J. The weakening summer circulation in the Northern Hemisphere mid-latitudes. Science 348, 324–327 (2015).

    Article  CAS  Google Scholar 

  17. 17

    Pithan, F. & Mauritsen, T. Arctic amplification dominated by temperature feedbacks in contemporary climate models. Nat. Geosci. 7, 181–184 (2014).

    Article  CAS  Google Scholar 

  18. 18

    Taylor, P. C. et al. A decomposition of feedback contributions to polar warming amplification. J. Clim. 26, 7023–7043 (2013).

    Article  Google Scholar 

  19. 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).

    Google Scholar 

  20. 20

    Overland, J. E. & Wang, M. Y. Large-scale atmospheric circulation changes are associated with the recent loss of Arctic sea ice. Tellus A 62, 1–9 (2010).

    Article  Google Scholar 

  21. 21

    Francis, J. A. & Vavrus, S. J. Evidence linking Arctic amplification to extreme weather in mid-latitudes. Geophys. Res. Lett. 39, L06801 (2012).

    Article  Google Scholar 

  22. 22

    Palmer, T. N. A nonlinear dynamical perspective on climate prediction. J. Clim. 12, 575–591 (1999).

    Article  Google Scholar 

  23. 23

    Pearl, J. Causality: Models, Reasoning and Inference 2nd edn (Cambridge Univ. Press, 2009).

    Google Scholar 

  24. 24

    Hannart, A., Pearl, J., Otto, F. E. L., Naveau, P. & Ghil, M. Causal counterfactual theory for the attribution of weather and climate-related events. Bull. Am. Meteorol. Soc. 97, 99–110 (2015).

    Article  Google Scholar 

  25. 25

    Vihma, T. Effects of Arctic sea ice decline on weather and climate: a review. Surv. Geophys. 35, 1175–1214 (2014).

    Article  Google Scholar 

  26. 26

    Walsh, J. E. Intensified warming of the Arctic: causes and impacts on middle latitudes. Global Planet. Change 117, 52–63 (2014).

    Article  Google Scholar 

  27. 27

    Thomas, K. (ed.) Linkages between Arctic Warming and Mid-Latitude Weather Patterns (National Academies, 2014).

    Google Scholar 

  28. 28

    Cohen, J. et al. Recent Arctic amplification and extreme mid-latitude weather. Nat. Geosci. 7, 627–637 (2014).

    Article  CAS  Google Scholar 

  29. 29

    Jung, T. et al. Polar lower-latitude linkages and their role in weather and climate prediction. Bull. Am. Meteorol. Soc. 96, ES197–ES200 (2015).

    Article  Google Scholar 

  30. 30

    Hopsch, S., Cohen, J. & Dethloff, K. Analysis of a link between fall Arctic sea ice concentration and atmospheric patterns in the following winter. Tellus A 64, 18624 (2012).

    Article  Google Scholar 

  31. 31

    Lee, M.-Y., Hong, C.-C. & Hsu, H.-H. Compounding effects of warm SST and reduced sea ice on the extreme circulation over the extratropical North Pacific and North America during the 2013–2014 boreal winter. Geophys. Res. Lett. 42, 1612–1618 (2015).

    Article  Google Scholar 

  32. 32

    Kug, J.-S. et al. Two distinct influences of Arctic warming on cold winters over North America and East Asia. Nat. Geosci. 8, 759–762 (2015).

    Article  CAS  Google Scholar 

  33. 33

    King, M. P., Hell, M. & Keenlyside, N. Investigation of the atmospheric mechanisms related to the autumn sea ice and winter circulation link in the Northern Hemisphere. Clim. Dynam. 46, 1185–1195 (2015).

    Article  Google Scholar 

  34. 34

    Pedersen, R., Cvijanovic, I., Langen, P. & Vinther, B. The impact of regional Arctic sea ice loss on atmospheric circulation and the NAO. J. Clim. 29, 889–902 (2016).

    Article  Google Scholar 

  35. 35

    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).

    Article  Google Scholar 

  36. 36

    Furtado, J. C., Cohen, J. L. & Tziperman, E. The combined influences of autumnal snow and sea ice on Northern Hemisphere winters. Geophys. Res. Lett. 43, 3478–3485 (2016).

    Article  Google Scholar 

  37. 37

    Dobricic, S., Vignati, E. & Russo, S. Large-scale atmospheric warming in winter and the Arctic sea ice retreat. J. Clim. 29, 2869–2888 (2016).

    Article  Google Scholar 

  38. 38

    Rinke, A., Dethloff, K., Dorn, W., Handorf, D. & Moore, J. C. Simulated Arctic atmospheric feedbacks associated with late summer sea ice anomalies. J. Geophys. Res. 118, 7698–7714 (2013).

    Google Scholar 

  39. 39

    Nakamura, T. et al. A negative phase shift of the winter AO/NAO due to the recent Arctic sea-ice reduction in late autumn. J. Geophys. Res. 120, 3209–3227 (2015).

    Article  Google Scholar 

  40. 40

    Duarte, C., Lenton, T., Wadhams, P. & Wassmann, P. Abrupt climate change in the Arctic. Nat. Clim. Change 2, 60–62 (2012).

    Article  Google Scholar 

  41. 41

    Wu, B., Handorf, D., Dethloff, K., Rinke, A. & Hu, A. Winter weather patterns over northern Eurasia and Arctic sea ice loss. Mon. Weather Rev. 141, 3786–3800 (2013).

    Article  Google Scholar 

  42. 42

    Corti, S., Molteni, F. & Palmer, T. N. Signature of recent climate change in frequencies of natural atmospheric circulation regimes. Nature 396, 799–802 (1999).

    Article  CAS  Google Scholar 

  43. 43

    Itoh, H. & Kimoto, M. Weather regimes, low-frequency oscillations, and principal patterns of variability: A perspective of extratropical low-frequency variability. J. Atmos. Sci. 56, 2684–2705 (1999).

    Article  Google Scholar 

  44. 44

    Sempf, M., Dethloff, K., Handorf, D. & Kurgansky, M. V. Toward understanding the dynamical origin of atmospheric regime behavior in a baroclinic model. J. Atmos. Sci. 64, 887–904 (2007).

    Article  Google Scholar 

  45. 45

    Slingo, J. & Palmer, T. Uncertainty in weather and climate prediction. Phil. Trans. R. Soc. A 369, 4751–4767 (2011).

    Article  Google Scholar 

  46. 46

    Schmeits, M. J. & Dijkstra, H. A. Bimodal behavior of the Kuroshio and the Gulf Stream. J. Phys. Oceanogr. 31, 3435–3456 (2001).

    Article  Google Scholar 

  47. 47

    Davos, V. et al. Methods for detecting early warnings of critical transitions in time series illustrated using ecological data. PLoS ONE 7, e41010 (2013).

    Google Scholar 

  48. 48

    Screen, J. A., Deser, C. & Sun, L. Projected changes in regional climate extremes arising from Arctic sea ice loss. Environ. Res. Lett. 10, 084006 (2015).

    Article  Google Scholar 

  49. 49

    Overland, J. E. & Wang, M. Increased variability in the early winter subarctic North American atmospheric circulation. J. Clim. 28, 7297–7305 (2015).

    Article  Google Scholar 

  50. 50

    Cohen, J. An observational analysis: Tropical relative to Arctic influence on midlatitude weather in the era of Arctic amplification. Geophys. Res. Lett. 43, 5287–5294 (2016).

    Article  Google Scholar 

  51. 51

    Hanna, E., Cropper, T. E., Jones, P. D., Scaife, A. A. & Allan, R. Recent seasonal asymmetric changes in the NAO (a marked summer decline and increased winter variability) and associated changes in the AO and Greenland Blocking Index. Int. J. Climatol. 35, 2540–2554 (2015).

    Article  Google Scholar 

  52. 52

    Woollings, T., Hannachi, A. & Hoskins, B. Variability of the North Atlantic eddy-driven jet stream. Q. J. Roy. Meteorol. Soc. 136, 856–868 (2010).

    Article  Google Scholar 

  53. 53

    Hanna, E., Cropper, T. E., Hall, R. J. & Cappelen, J. Greenland Blocking Index 1851–2015: a regional climate change signal. Int. J. Climatol. http://doi.org/brqf (2016).

  54. 54

    Masato, G., Hoskins, B. J. & Woollings, T. Winter and summer Northern Hemisphere blocking in CMIP5 models. J. Clim. 26, 7044–7059 (2013).

    Article  Google Scholar 

  55. 55

    Scaife, A. A. et al. Skillful long-range prediction of European and North American winters. Geophys. Res. Lett. 41, 2514–2519 (2014).

    Article  Google Scholar 

  56. 56

    Eade, R. et al. Do seasonal-to-decadal climate predictions underestimate the predictability of the real world? Geophys. Res. Lett. 41, 5620–5628 (2014).

    Article  Google Scholar 

  57. 57

    Stockdale, T. N. et al. Atmospheric initial conditions and the predictability of the Arctic Oscillation. Geophys. Res. Lett. 42, 1173–1179 (2015).

    Article  Google Scholar 

  58. 58

    Barnes, E. A. & Polvani, L. M. CMIP5 projections of Arctic amplification, of the North American/North Atlantic Circulation, and of their relationship. J. Clim. 28, 5254–5271 (2015).

    Article  Google Scholar 

  59. 59

    Screen, J. A., Deser, C., Simmonds, I. & Tomas, R. Atmospheric impacts of Arctic sea-ice loss, 1979–2009: separating forced change from atmospheric internal variability. Clim. Dynam. 43, 333–344 (2014).

    Article  Google Scholar 

  60. 60

    Shepherd, T. G. Atmospheric circulation as a source of uncertainty in climate change projections. Nat. Geosci. 7, 703–708 (2014).

    Article  CAS  Google Scholar 

  61. 61

    Hinzmann, L. et al. Trajectory of the Arctic as an integrated system. Ecol. Appl. 23, 1837–1868 (2013).

    Article  Google Scholar 

  62. 62

    Carstensen, J. & Weydmann, A. Tipping points in the Arctic: eyeballing or statistical significance? AMBIO 41, 34–43 (2012).

    Article  Google Scholar 

  63. 63

    Eisenman, I. & Wettlaufer, J. S. Nonlinear threshold behavior during the loss of Arctic sea ice. Proc. Natl Acad. Sci. USA 106, 28–32 (2009).

    Article  Google Scholar 

  64. 64

    Mysak, L. A. & Venegas, S. A. Decadal climate oscillations in the Arctic: a new feedback loop for atmosphere–ice–ocean interactions. Geophys. Res. Lett. 25, 3607–3610 (1998).

    Article  Google Scholar 

  65. 65

    Billings, S. A., Chen, S. & Korenberg, M. J. Identification of MIMO non-linear systems using a forward-regression orthogonal estimator. Int. J. Control 49, 2157–2189 (1989).

    Article  Google Scholar 

  66. 66

    Billings, S. A. Nonlinear System Identification: NARMAX Methods in the Time, Frequency, and Spatio-Temporal Domains (Wiley, 2013).

    Google Scholar 

  67. 67

    Bigg, G. R. et al. A century of variation in the dependence of Greenland iceberg calving on ice sheet surface mass balance and regional climate change. Proc. R. Soc. A 470, 20130662 (2014).

    Article  CAS  Google Scholar 

  68. 68

    Kretschmer, M., Coumou, D., Donges, J. & Runge, J. Using causal effect networks to analyze different Arctic drivers of midlatitude winter circulation. J. Clim. 29, 4069–4081 (2016).

    Article  Google Scholar 

  69. 69

    Stanislawska, K., Krawiec, K. & Kundzewicz, Z. W. Modeling global temperature changes with genetic programming. Comput. Math. Appl. 64, 3717–3728 (2012).

    Article  Google Scholar 

  70. 70

    Honda, M., Inoue, J. & Yamane, S. Influence of low Arctic sea-ice minima on anomalously cold Eurasian winters. Geophys. Res. Lett. 36, L08707 (2009).

    Article  Google Scholar 

  71. 71

    Kim, B.-M. et al. Weakening of the stratospheric polar vortex by Arctic sea-ice loss. Nat. Commun. 5, 4646 (2014).

    Article  CAS  Google Scholar 

  72. 72

    Jaiser, R., Dethloff, K. & Handorf, D. Stratospheric response to Arctic sea ice retreat and associated planetary wave propagation changes. Tellus A 65, 19375 (2013).

    Article  Google Scholar 

  73. 73

    Handorf, D., Jaiser, R., Dethloff, K., Rinke, A. & Cohen, J. Impacts of Arctic sea-ice and continental snow-cover changes on atmospheric winter teleconnections. Geophys. Res. Lett. 42, 2367–2377 (2015).

    Article  Google Scholar 

  74. 74

    Luo, D. et al. Impact of Ural blocking on winter warm Arctic–cold Eurasian anomalies. Part I: blocking-induced amplification. J. Clim. 29, 3925–3947 (2016).

    Article  Google Scholar 

  75. 75

    Mori, M. Watanabe, M., Shiogama, H., Inoue, J. & Kimoto, M. Robust Arctic sea-ice influence on the frequent Eurasian cold winters in past decades. Nat. Geosci. 7, 869–873 (2014).

    Article  CAS  Google Scholar 

  76. 76

    Ding, Q. et al. Tropical forcing of the recent rapid Arctic warming in northeastern Canada and Greenland. Nature 509, 209–212 (2014).

    Article  CAS  Google Scholar 

  77. 77

    Perlwitz, J., Hoerling, M. & Dole, R. Arctic tropospheric warming: causes and linkages to lower latitudes. J. Clim. 28, 2154–2167 (2015).

    Article  Google Scholar 

  78. 78

    Hartmann, D. L. Pacific sea surface temperature and the winter of 2014. Geophys. Res. Lett. 42, 1894–1902 (2015).

    Article  Google Scholar 

  79. 79

    Screen J. & Francis, J. Contribution of sea-ice loss to Arctic amplification regulated by Pacific Ocean decadal variability. Nat. Clim. Change 6, 856–860 (2016).

    Article  Google Scholar 

  80. 80

    Sato, K., Inoue, J. & Watanabe, M. Influence of the Gulf Stream on the Barents Sea ice retreat and Eurasian coldness during early winter. Environ. Res. Lett. 9, 084009 (2014).

    Article  Google Scholar 

  81. 81

    Harvey, B. J., Shaffrey, L. C. & Woollings, T. Deconstructing the climate change response of the Northern Hemisphere wintertime storm tracks. Clim. Dynam. 45, 2847–2860 (2015).

    Article  Google Scholar 

  82. 82

    Feldstein, S. B. & Lee, S. Intraseasonal and interdecadal jet shifts in the Northern Hemisphere: The role of warm pool tropical convection and sea ice. J. Clim. 27, 6497–6518 (2014).

    Article  Google Scholar 

  83. 83

    Trenberth, K. E., Fasullo, J. T. & Shepherd, T. G. Attribution of climate extreme events. Nat. Clim. Change 5, 725–730 (2015).

    Article  Google Scholar 

  84. 84

    Sigmond, M. & Scinocca, J. F. The influence of the basic state on the Northern Hemisphere circulation response to climate change. J. Clim. 23, 1434–1446 (2010).

    Article  Google Scholar 

  85. 85

    Butler, A. H. et al. Defining sudden stratospheric warmings. Bull. Am. Meteorol. Soc. 96, 1913–1928 (2015).

    Article  Google Scholar 

  86. 86

    Sigmond, M., Scinocca, J. F., Kharin, V. V. & Shepherd, T. G. Enhanced seasonal forecast skill following stratospheric sudden warmings. Nat. Geosci. 6, 98–102 (2013).

    Article  CAS  Google Scholar 

  87. 87

    Handorf, D. & Dethloff, K. How well do state-of-the-art atmosphere–ocean general circulation models reproduce atmospheric teleconnection patterns? Tellus A 64, 19777 (2012).

    Article  Google Scholar 

  88. 88

    Byrkjedal, Ø., Esau, I. N. & Kvamstø, N. G. Sensitivity of simulated wintertime Arctic atmosphere to vertical resolution in the ARPEGE/IFS model. Clim. Dynam. 30, 687–701 (2008).

    Article  Google Scholar 

  89. 89

    Wu, Y. & Smith, K. L. Response of Northern Hemisphere midlatitude circulation to Arctic amplification in a simple atmospheric general circulation model. J. Clim. 29, 2041–2058 (2016).

    Article  Google Scholar 

  90. 90

    Anstey, J. A. et al. Multi-model analysis of Northern Hemisphere winter blocking: Model biases and the role of resolution. J. Geophys. Res. Atmos. 118, 3956–3971 (2013).

    Article  Google Scholar 

  91. 91

    Inoue, J. et al. Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route. Sci. Rep. 5, 16868 (2015).

    Article  CAS  Google Scholar 

  92. 92

    Schlichtholz, P. Empirical relationships between summertime oceanic heat anomalies in the Nordic seas and large-scale atmospheric circulation in the following winter. Clim. Dynam. 47, 1735–1753 (2016).

    Article  Google Scholar 

  93. 93

    Lindsay, R., Wensnahan, M., Schweiger, A. & Zhang, J. Evaluation of seven different atmospheric reanalysis products in the Arctic. J. Clim. 27, 2588–2606 (2014).

    Article  Google Scholar 

  94. 94

    Handorf, D., Dethloff, K., Marshall, A. G. & Lynch, A. Climate regime variability for past and present time slices simulated by the Fast Ocean Atmosphere Model. J. Clim. 22, 58–70 (2009).

    Article  Google Scholar 

  95. 95

    Gervais, M., Atallah, E., Gyakum, J. R. & Tremblay, L. B. Arctic air masses in a warming world. J. Clim. 29, 2359–2373 (2016).

    Article  Google Scholar 

  96. 96

    Francis, J. & Skific, N. Evidence linking rapid Arctic warming to mid-latitude weather patterns. Phil. Trans. R. Soc. 373, 20140170 (2015).

    Article  Google Scholar 

  97. 97

    Screen, J. A. & Simmonds, I. Amplified mid-latitude planetary waves favour particular regional weather extremes. Nat. Clim. Change 4, 704–709 (2014).

    Article  Google Scholar 

  98. 98

    Singh, D. et al. Recent amplification of the North American winter temperature dipole. J. Geophys. Res. 121, 9911–9928, (2016).

    Google Scholar 

  99. 99

    Di Capua, G. & Coumou, D. Changes in meandering of the Northern Hemisphere circulation. Environ. Res. Lett. 11, 094028 (2016).

    Article  Google Scholar 

Download references

Acknowledgements

J.E.O. is supported by NOAA Arctic Research Project of the Climate Program Office. J.A.F. is supported by NSF/ARCSS Grant 1304097. K.D. acknowledges support from the German DFG Transregional Collaborative Research Centre TR 172. J.A.S. was funded by the UK Natural Environment Research Council grants NE/J019585/1 and NE/M006123/1. R.J.H. and E.H. acknowledge support from the University of Sheffield's Project Sunshine. S.-J.K. was supported by the project of Korea Polar Research Institute (PE16010), and T.V. was supported by the Academy of Finland (Contract 259537). We appreciate the support of IASC, CliC and the University of Sheffield for hosting a productive workshop. PMEL Contribution Number 4429.

Author information

Affiliations

Authors

Contributions

J.E.O. was the coordinating author and all other authors contributed ideas, analyses and text.

Corresponding author

Correspondence to James E. Overland.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Fig. 1

Prescribed surface boundary conditions. (PDF 1460 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Overland, J., Dethloff, K., Francis, J. et al. Nonlinear response of mid-latitude weather to the changing Arctic. Nature Clim Change 6, 992–999 (2016). https://doi.org/10.1038/nclimate3121

Download citation

Further reading

Search

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing