Human contribution to extreme weather
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Nature Climate Change
Embargo
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London: Monday 27 April 2015 16:00 (BST)
New York: Monday 27 April 2015 11:00 (EDT)
Tokyo: Tuesday 28 April 2015 00:00 (JST)
Sydney: Tuesday 28 April 2015 01:00 (AEST)
Present day global warming, most likely caused by human activity, is responsible
for about 18% of heavy precipitation and 75% of hot temperature
extremes worldwide, reports a paper published online in Nature Climate Change. This
proportion is shown to increase with further warming; for example modelling indicates that if
temperatures increase to 2 °C higher than pre-industrial levels, about 40% of precipitation
extremes will be a result of human influence.
Erich Fischer and Reto Knutti use two metrics to determine what proportion of global high
temperature and heavy precipitation events can be attributed to human influence. The metrics
are applied to daily outputs from 25 climate models considering 1901–2005 historical
simulations and 2006–2100 projections with a high-emission scenario. The authors suggest
that the rarest and most extreme events are likely to be more heavily influenced by
greenhouse-gas emissions. They note that using a global perspective allows more robust
estimates of the effect of warming on extreme events than efforts focusing on single events,
where modelling uncertainties can be large.
In an accompanying News & Views, Peter Stott points out that the study can “provide maps
of how probabilities of extreme temperatures and precipitation have changed across the
globe, [however] the framework they use means that such probabilities cannot be applied to
specific individual extreme weather events.”
Article and author details
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Anthropogenic contribution to global occurrence of heavy-precipitation
and high-temperature extremes
Corresponding Author
Erich Fischer
ETH Zürich, Zürich, Switzerland
Email: erich.fischer@env.ethz.ch, Tel: +41 44 632 82 41
News & Views Author
Peter Stott, Exeter
Met Office Hadley Centre, Exeter, United Kingdom
Email: peter.stott@metoffice.gov.uk, Tel: +44 1392 886646
DOI
10.1038/nclimate2617
Online paper*
http://nature.com/articles/doi:10.1038/nclimate2617
* Please link to the article in online versions of your report (the URL will go live after the embargo
ends).
Geographical listings of authors
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Switzerland