From The Washington Post (Chris Mooney):
Last week, some people got really mad at Bill Nye the Science Guy. How come? Because he had the gall to say this on Twitter:
“Billion$$ in damage in Texas & Oklahoma. Still no weather-caster may utter the phrase Climate Change.”
Nye’s comments, and the reaction to them, raise a perennial issue: How do we accurately parse the relationship between climate change and extreme weather events, as they occur in real time?
It’s a particularly pressing question of late, following not only catastrophic floods in Texas and Oklahoma, but also a historic heatwave in India that has killed over 2,000 people so far, and President Obama’s recent trip to the National Hurricane Center in Miami, where he explicitly invoked the idea that global warming will make these storms worse (which also drew criticism).
As the Nye case indicates, there is still a lot of pushback whenever anyone dares to link climate change to extreme weather events. But we don’t have to be afraid to talk about this relationship. We merely have to be scrupulously accurate in doing so, and let scientists lead the way.
Take the floods. One exemplary voice here has been Texas Tech climate researcher (and evangelical Christian) Katharine Hayhoe, who took to Facebook to explain the science. As Hayhoe noted, climate change doesn’t “cause” individual extreme events, in this case or in others. But “just like steroids make a baseball player stronger, climate change EXACERBATES many of our weather extremes, making many of them, on average, worse than they would have been naturally,” she said.
Thus, Hayhoe treated the link between a changing climate and the floods not as a matter of simple causation, but as a matter of context. She notes that overall, “heavy rainfall and flood risk is increasing,” due to the fact that warming charges the atmosphere with more water vapor, which is then more available to fall in individual precipitation events.[…]
And what about India’s extreme heat? Here again, we must bear in mind that extreme weather events are not directly caused by climate change. Indeed, weather extremes can occur — and weather records can break — due solely to natural climate variability.
Nonetheless, and as with past major heat extremes, such as Australia’s 2012-2013 “angry summer,” the odds of an event like this one occurring may have shifted. Indeed, meteorologist Jeff Masters of the Weather Underground has directly stated that the heat wave “was made much more probable by the fact that Earth is experiencing its hottest temperatures on record.”