The Connection Between Climate Change and Extreme Weather
New Studies Show That Climate Change Is the Culprit in Extreme Rain – Bryan Walsh
Bryan Walsh of Time Magazine hits the nail on the head when he writes that
Perhaps the biggest challenge facing climate scientists today is fingerprinting—proving that extreme weather events like droughts, heat waves and floods are actually being caused by manmade climate change.
Though climate scientists have overwhelmingly purported that impacts of global warming will manifest in higher temperatures, changes in precipitation, and rising sea levels, scientists still remain less certain when assigning blame for extreme weather events such as hurricanes, droughts, and flooding.
A new study by Nature seeks to make that connection. By analyzing the causes behind the rise in storms and heavy snowfall over the past century, researchers from Canada and Toronto posit that heavy precipitation is at least partly due to the growing concentration of manmade greenhouse gas emissions in the atmosphere. Ergo, as Francis Zwiers, the study’s lead researcher notes,
Human influence on the climate system [such as CO2 emissions] has the effect of intensifying precipitation extremes [such as floods and droughts].
As Walsh writes in his article,
That conclusion shouldn’t be that surprising—climatologists have predicted an uptick in extreme weather events as greenhouse gas concentrations in the atmosphere increase. Since warmer air can carry more water vapor, a warmer planet should see heavier rain and other precipitation—and that’s what we’ve begun to see with actual weather.
However, the devil is always in the details. Though the Nature article posits a clear correlation between rising green house gas emissions and extreme weather events, the report refrains from standing behind a distinct causal relationship between the two, which is the reservation put forth by Judith Curry – atmospheric scientist at Georgia Tech – and Roger Pielke Jr. – a professor of environmental studies at the University of Colorado.
As Pielke writes,
Precipitation is to flood damage as wind is to windstorm damage. It is not enough to say that it has become windier to make a connection to increased windstorm damage — you need to show a specific increase in those specific wind events that actually cause damage. There are a lot of days that could be windier with no increase in damage; the same goes for precipitation.
Similarly, Andrew Revkin of Dot Earth criticizes the report for dramatizing the outcomes of global warming on extreme weather events while at the same time not clearly making connections within the report.
As Revkin asserts,
the authors and journal are trying to have things both ways — including definitive statements in abstracts and summaries that draw the attention of the press and public, but then saying, no, this is not definitive.
The planet’s atmosphere and weather patterns operate under extremely complex circumstances and despite the lack of distinct and undeniable data outlining the casual relationship between manmade climate change and extreme weather events, the indicators are still there.
As Paul Krugman noted in a recent article in the New York Times,
As always, you can’t attribute any one weather event to greenhouse gases. But the pattern we’re seeing, with extreme highs and extreme weather in general becoming much more common, is just what you’d expect from climate change.
One can only speculate the implications that this will have on U.S. national and economic security, but with billions of dollars for climate adaptation at stake, our national security is best served by taking action now. By reducing greenhouse gas emissions we are more likely to limit economic disruptions due to extreme weather events such as flooding and droughts. As Walsh writes, we may not be able to “convict climate change for extreme events like the Pakistani floods or the Russian heat wave – and maybe we’ll never be able to do it. But we’ll still have to live with a changing climate.”
