Climate change is making extreme weather worse. It tripled the risk of Hurricane Harvey’s record rainfall over Texas in 2017. It made Australia’s devastating wildfires in 2019 and 2020 at least 30 percent more likely. And it made a heat wave that ravaged the Pacific Northwest in 2021 at least 150 times more likely.
These are all findings of scientific studies. But how do scientists figure out how much climate change is to blame for any given weather event?
A variety of methods can help answer that question. This type of work is known as extreme event attribution.
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One common method compares two versions of the world. The first is the real world — where humans burning fossil fuels have caused global warming. The second is what the world would look like without climate change. Scientists estimate what that second world would look like based on historical weather data and climate models.
With some clever number-crunching, researchers can see how likely or severe a weather event is in each of those versions of the world.
Hundreds of studies have probed the role of global warming in natural disasters. Many have found that climate change made extreme weather worse. In some cases, studies have shown that a specific weather event would have been almost impossible without climate change. One example is a brutal heat wave that struck Siberia in 2020. That year, Siberia saw temperatures around 30° Celsius (86° Fahrenheit). It would usually have been closer to freezing at that time of year.
This type of research highlights how climate change is already impacting our daily lives. It also offers clues about the types of weather people should prepare for as the world keeps warming.
Scientists have investigated the role of climate change in hundreds of natural disasters around the globe. Here’s how.
Want to know more? We’ve got some stories to get you started:
Explainer: What is attribution science? This relatively new field of research is looking into what might explain extreme weather events. (7/30/2019) Readability: 7.1
Siberian heat wave that caused an oil spill made more likely by climate change Extreme temperatures from January to June 2020 led to wildfires and thawing permafrost. (8/13/2020) Readability: 8.3
Climate change drove Australian wildfires to extremes The region’s warming climate boosted wildfire risk in the region by at least 30 percent. (4/29/2020) Readability: 8.0
Explore more
Fingerprints of climate change shows up in some extreme weather
Explainer: Why are so many hurricanes strengthening really fast?
Let’s learn about why summer 2023 was so hot
Activities
Carbon Brief catalogs every attribution study done to date. On their website, you can find a map of weather events around the world that scientists have investigated through attribution science. Explore weather events by year, type of weather and if researchers found that climate change played a role in an event. What trends do you notice?
