“When it rains it pours”-the science of extreme weather attribution

“A man with a conviction is a hard man to change. Tell him you disagree and he turns away. Show him facts or figures and he questions your sources. Appeal to logic and he fails to see your point. We are familiar with the variety of ingenious defenses with which people protect their convictions, managing to keep them unscathed through the most devastating attacks.”

-Leon Festinger, When Prophecy Fails (1956)

I am sure we can all relate to the quote above. How many times have you tried to argue your point with the most sound logic only to have it fall on deaf ears, or worse, further cementing the listener’s views more completely? This can be a truly frustrating and seemingly futile experience but facts do matter.


For scientists, this issue of facts and scientific consensus is at the forefront lately. Certain scientific topics have become politicized in order to create doubt where none exists (see here); at least not in the scientific community. When external forces are deliberately trying to discredit someone’s research or sometimes even the scientist themselves, this can become a huge battle that most scientists aren’t trained to deal with. For these folks, who have dedicated much of their life in the pursuit of knowledge for its own sake – fueled by their scientific curiosity, thoughtfully and carefully conducting research through empirical studies, experiments, or creating models to help explain phenomena – now find themselves with their backs up against the wall. Nowhere is this more obvious than the “controversy” over global climate change.

A little humor from political cartoonist Tom Toles.

I am not going to lay out the many reasons we know that climate change is happening and that human activities are responsible. However, if you are interested, the facts are overwhelming (carbon isotopes, ice cores, hockey stick figure, sea level rise, global temperature rise, warming oceans, shrinking ice sheets, declining sea ice, glacial retreats, decreased snow cover, ocean acidification, extreme weather). We have also covered this topic many times in different ways (here, here, here, and here). The argument from climate change doubters has shifted (a little) over time. At first the notion that humans could cause climate change was totally rejected by these doubters but overtime their argument has become more nuanced. Now many climate change doubters will admit that human activity has some role in climate change but they then say it is too hard to predict what the impacts of such climate change will be.

Food for thought from editorial cartoonist Joel Pett.

Its easy to understand why the predictions of sea level rise of several inches or the globe warming a couple degrees does not seem pressing enough or seems too far in the future to move people to action. Plus the science behind these predictions can be esoteric. However, one of the most immediate ways we can feel the impacts of climate change is through extreme weather events.

In the past scientists hesitated to attribute one storm or natural disaster to climate change. At the time, the mantra for climate scientists was that you cannot accurately attribute any one event to climate change, but rather you can look at the trends over time to see if there is a discernable pattern or fingerprint of a warming globe. However, this is no longer the case. Last March (2016) the National Academies of Sciences, Engineering, and Medicine released a report called “Attribution of Extreme Weather Events in the Context of Climate Change”. This report outlines the concept and application of extreme weather attribution. Essentially, sophisticated climate models (a model is a way to explain and test a phenomenon that you can not otherwise replicate in the real world) now allow scientists to determine the probability or intensity of an event under two different scenarios – with climate change and without climate change. This has huge implications! And not just for the scientific community but for all folks potentially impacted by extreme weather events.

From: https://www.nap.edu/catalog/21852/attribution-of-extreme-weather-events-in-the-context-of-climate-change

“How?” you might ask? Well, the model allows us determine the probability of a certain extreme weather event (let’s say a heatwave) and then analyze how climate change can exacerbate that event (for example it may be twice as likely under a warming climate). These results will allow for the creation of actionable plans to mitigate lives lost or property damage. And importantly it is based on scientific evidence rather than just a best guess. So now this nuanced argument of how hard it is to predict the impacts of climate change holds little weight because we can confidently say that climate change can result in extreme weather events.

From: https://www.slideshare.net/LearnMoreAboutClimate/attribution-of-extreme-weather

Perhaps, for some people, it may not be compelling to save the polar bears or worry about the bleaching of coral reefs, but hopefully by making the case for how climate change directly impacts humans now and in real world terms it will move to action even the most strident of climate change doubters.

“Experience is the best teacher, but a fool will learn from no other.”

-Benjamin Franklin

OR a not so harsh interpretation

“The best teacher is experience and not through someone’s distorted point of view.”

-Jack Kerouac, On the Road (1957)

Please check out these videos for further information:

Heidi Cullen (no relation) discusses the problem about climate change being an unsexy problem.


and here she talks about the topic of extreme weather attribution in more detail.


This video goes into more detail about extreme weather attribution and the potential applications.