Record-shattering events spur advances in tying climate change to extreme weather
Scientists quickly began working to figure out how much of the blame for the heat wave could be laid to global warming. But the heat was so unusual, the weather so weird, that it broke their methods. “It challenged our techniques, our climate models, and our statistical analysis methods,” says Michael Wehner, a climate scientist at Lawrence Berkeley National Laboratory who participates in the World Weather Attribution (WWA) initiative. WWA ultimately issued a statement, finding the heat wave was “virtually impossible” without global warming. But, Wehner admits, that statement masked plenty of doubts. “We sort of kludged it.”
Next time, he and fellow modelers expect to do better.
Critics complain that extreme event attribution, as the effort is known, overemphasizes public communications and underestimates uncertainty. But new approaches promise to increase the field’s rigor and more precisely capture the relationship between climate change and extreme weather—even for events so extreme that there is no historical record for comparison.
And the studies have led to new insights, Wehner says, for instance by showing that warming can increase hurricane flooding even more than expected and exposing how poorly models handle local causes of heat waves.
But these efforts rely on climate models with known biases that often fail to capture the detailed, local weather phenomena behind a heat wave or a flood.