Extreme event attribution, also known as attribution science, is a relatively new field of study in

meteorology Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not ...

and climate science that tries to measure how ongoing

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

directly affects recent

extreme weather Extreme weather or extreme climate events includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Often, extreme events are based on a locat ...

events. Attribution science aims to determine which such recent events can be explained by or linked to a warming atmosphere and are not simply due to natural variations.

History

Attribution science was first mentioned in a 2011 "State of the Climate" published by the

American Meteorological Society The American Meteorological Society (AMS) is the premier scientific and professional organization in the United States promoting and disseminating information about the Atmospheric sciences, atmospheric, Oceanography, oceanic, and Hydrology, hydr ...

which stated that climate change is linked to six extreme weather events that were studied.

Purpose, methods and findings

German climatologist

Friederike Otto Friederike (Fredi) Elly Luise Otto (born 29 August 1982) is a climatologist who as of December 2021 works as a Senior Lecturer at the Grantham Institute for Climate Change and the Environment at Imperial College London. Previously she was Associ ...

posited that attribution science aims to answer the question, "did climate change play a role" in specific extreme events "within the news time frame – so within two weeks of the event". Attribution studies generally proceed in four steps: (1) measuring the magnitude and frequency of a given event based on observed data, (2) running computer models to compare with and verify observation data, (3) running the same models on a baseline "Earth" with no climate change, and (4) using statistics to analyze the differences between the second and third steps, thereby measuring the direct effect of climate change on the studied event. Heatwaves are the easiest weather events to attribute. Climate change can affect the intensity and frequency of extreme weather differently, for example the 2010 Russia heat wave was made far more likely but not more intense.

Applications and implications

Attribution science may affect climate change litigation, perhaps by increasing lawsuits against companies for causing and governments for not addressing climate change.

Examples

* A review summarized confidence, probabilities and costs-severities – such as economic costs, financial costs and number of early losses of life – of links to climate change and identified potential ways for the improvement of the field such as "improving the recording of extreme weather impacts around the world, improving the coverage of attribution studies across different events and regions, and using attribution studies to explore the contributions of both climate and non-climate drivers of impacts." * Scientists of the international

World Weather Attribution World Weather Attribution is an academic collaboration studying extreme event attribution, calculations of the impact of climate change on extreme meteorological events such as heat waves, droughts, and storms. When an extreme event occurs, the p ...

project publicized a study that found that human-caused climate change had an influence on the 2019–20 Australian wildfires by causing high-risk conditions that made widespread burning at least 30 percent more likely. They comment on the results, stating that climate change probably had more effects on the fires which couldn't be attributed using their

climate simulation Numerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the cl ...

s and that not all drivers of the fires showed imprints of anthropogenic climate change. * The World Weather Attribution initiative has attributed the

2021 Western North America heat wave The 2021 Western North America heat wave was an extreme heat wave that affected much of Western North America from late June through mid-July 2021. Rapid attribution analysis found this was a 1000-year weather event, made 150 times more likely ...

to climate change. * Further analyses can be found on the WWA's website. * The Climate Attribution Database contains scientific resources organized by theme. * A study of 2020 storms of at least tropical storm-strength published in ''

Nature Communications ''Nature Communications'' is a peer-reviewed, open access, scientific journal published by Nature Portfolio since 2010. It is a multidisciplinary journal and it covers the natural sciences, including physics, chemistry, earth sciences, medicine, ...

'' concluded that human-induced climate change increased extreme 3-hourly storm rainfall rates by 10%, and extreme 3-day accumulated rainfall amounts by 5%. For hurricane-strength storms, the figures increased to 11% and 8%. * As of October 2022, the United States had been affected by 15 weather/climate disaster events, each with losses surpassing $1 billion.

References

External links