Determining the time of emergence of climates altered from their natural state by anthropogenic influences can help inform the development of adaptation and mitigation strategies to climate change. Previous studies have examined the time of emergence of climate averages. However, at the global scale, the emergence of changes in extreme events, which have the greatest societal impacts, has not been investigated before. Based on state-of-the-art climate models, we show that temperature extremes generally emerge slightly later from their quasi-natural climate state than seasonal means, due to greater variability in extremes. Nevertheless, according to model evidence, both hot and cold extremes have already emerged across many areas. Remarkably, even precipitation extremes that have very large variability are projected to emerge in the coming decades in Northern Hemisphere winters associated with a wettening trend. Based on our findings we expect local temperature and precipitation extremes to already differ significantly from their previous quasi-natural state at many locations or to do so in the near future. Our findings have implications for climate impacts and detection and attribution studies assessing observed changes in regional climate extremes by showing whether they will likely find a fingerprint of anthropogenic climate change.
ARC Centre of Excellence for Climate System Science, Climate Change Research Centre, University of New South Wales, Sydney, 2052, Australia;ARC Centre of Excellence for Climate System Science, School of Earth Science, University of Melbourne, Melbourne, 3010, Australia;ARC Centre of Excellence for Climate System Science, Climate Change Research Centre, University of New South Wales, Sydney, 2052, Australia;Institute for Atmospheric and Climate Science, ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland;National Centre for Atmospheric Science, Department of Meteorology, University of Reading, Reading, RG6 6BB, UK;ARC Centre of Excellence for Climate System Science, Climate Change Research Centre, University of New South Wales, Sydney, 2052, Australia;ARC Centre of Excellence for Climate System Science, School of Earth Science, University of Melbourne, Melbourne, 3010, Australia;ARC Centre of Excellence for Climate System Science, School of Earth Science, University of Melbourne, Melbourne, 3010, Australia;ARC Centre of Excellence for Climate System Science, School of Earth Science, University of Melbourne, Melbourne, 3010, Australia;ARC Centre of Excellence for Climate System Science, School of Earth Sciences, The Australian National University, Acton, 2601, Australia;ARC Centre of Excellence for Climate System Science, Climate Change Research Centre, University of New South Wales, Sydney, 2052, Australia
Recommended Citation:
Andrew D King,Markus G Donat,Erich M Fischer,et al. The timing of anthropogenic emergence in simulated climate extremes[J]. Environmental Research Letters,2015-01-01,10(9)