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  • Brief Communications Arising
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Uncertainties in the timing of unprecedented climates

A Brief Communications Arising to this article was published on 02 July 2014


Arising from C. Mora et al. Nature 502, 183–187 (2013)

The question of when the signal of climate change will emerge from the background noise of climate variability—the ‘time of emergence’—is potentially important for adaptation planning. Mora et al.1 presented precise projections of the time of emergence of unprecedented regional climates. However, their methodology produces artificially early dates at which specific regions will permanently experience unprecedented climates and artificially low uncertainty in those dates everywhere. This overconfidence could impair the effectiveness of climate risk management decisions2. There is a Reply to this Brief Communication Arising by Mora, C. et al. Nature 511, (2014).

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Figure 1: The year of unprecedented emergence for surface air temperature using RCP4.5.

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Authors and Affiliations



E.H. led the analysis and writing of the manuscript. B.A., N.D. and I.M. performed additional analyses, discussed the results and contributed text. All other authors contributed text.

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Correspondence to Ed Hawkins.

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Hawkins, E., Anderson, B., Diffenbaugh, N. et al. Uncertainties in the timing of unprecedented climates. Nature 511, E3–E5 (2014).

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