Study links extreme weather to climate change

Mar 11, 2016, 3:32 PM EST
(Source: Neva Swensen/flickr)
(Source: Neva Swensen/flickr)
For years, climate scientists have suspected that extreme weather patterns or disastrous events such as Hurricane Katrina were linked to global warming. Now, new research fortifies the link between climate change and these weather disasters. The New York Times reports:
One view holds that no single storm or drought can be linked to climate change. The other argues that all such things are, in some sense, “caused” by climate change, because we have fundamentally altered the global climate and all the weather in it.
While true, this “all in” philosophy doesn’t adequately emphasize the fact that not all of the extreme weather we experience today has changed significantly. Some of it is just, well, the weather.
But some of our weather has changed significantly, and now a new report from the National Academies of Sciences, Engineering and Medicine has outlined a rigorous, defensible, science-based system of extreme weather attribution to determine which events are tied to climate change.
“The days of saying no single weather event can be linked to climate change are over,” says Heidi Cullen, chief scientist at Climate Central, a nonprofit news organization that reports on global warming. “This report makes a really important contribution in linking global warming to extreme weather.”
The report follows a decade of research by a variety of scientists in different fields dedicated to attributing weather to climate change. The new field has evolved rapidly, though it still can’t provide quick and definitive answers for every weather event. Scientists are best equipped to show the connection between extreme weather events and climate change when the effects are closely related to temperature. Extreme heat and extreme cold are the easiest to attribute to climate change, followed by drought and extreme rainfall. The effect of climate change on weather events like tornadoes and wildfires can be especially difficult to assess because of the many variables that come into play, including factors beyond weather, like settlement patterns.
“Heavy rainfall is influenced by a moister atmosphere, which is a relatively direct consequence of human-induced warming, though not as direct as the increase in temperature itself,” the report finds.
But there are also “greater levels of uncertainty for events that are not directly temperature related,” the research finds. It says that the uncertainty is highest when it comes to attributing wildfires (which, after all, can be started by human carelessness), extra-tropical cyclones (winter storms or blizzards), and severe-convective storms (thunderstorms that can produce tornadoes) to climate change.