Towards reliable extreme weather and climate event attribution

• Published in: Nature communications Vol. 10; no. 1; pp. 1732 - 7
• Main Authors: Bellprat, Omar, Guemas, Virginie, Doblas-Reyes, Francisco, Donat, Markus G.
• Format: Journal Article Publication
• Language: English
• Published: London Nature Publishing Group UK 15-04-2019; Nature Publishing Group; Nature Research; Nature Portfolio
• Subjects: 704/106/694/2786; 704/106/694/674; Canvis climàtics; Climate change; Climate models; Climate science; Computer simulation; Energies; Environmental assessment; Environmental risk; Error correction; Extreme heat; Extreme weather; Human influences; Humanities and Social Sciences; multidisciplinary; Public concern; Science; Science (multidisciplinary); Trustworthiness; Weather forecasting; Àrees temàtiques de la UPC
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-09729-2

Climate change is shaping extreme heat and rain. To what degree human activity has increased the risk of high impact events is of high public concern and still heavily debated. Recent studies attributed single extreme events to climate change by comparing climate model experiments where the influence of an external driver can be included or artificially suppressed. Many of these results however did not properly account for model errors in simulating the probabilities of extreme event occurrences. Here we show, exploiting advanced correction techniques from the weather forecasting field, that correcting properly for model probabilities alters the attributable risk of extreme events to climate change. This study illustrates the need to correct for this type of model error in order to provide trustworthy assessments of climate change impacts.
Understanding how climate change has shaped past high impact events requires reliable probabilities of extreme event occurrences. This study demonstrates how often overlooked techniques from weather forecasting can yield more reliable assessments of climate change impacts.