Climate science is confusing. For decades, scientists have said that more CO2 means higher temperatures, longer dry spells, worse storms. But ask them whether global warming caused a Midwest heatwave, the California drought, or a New York hurricane, and they'll explain ad nauseum how hard it is to untangle whether any single weather event is due to natural variation or climate change.
Hard, but not impossible. A new NOAA report released November 5 looked at how (or how not) climate change affected 28 different global events in 2014. These aren't just nods of acknowledgement: Each study attempts to quantify how much climate change affected the duration, geographic extent, and severity of the weather event in question. For some events—like heat waves—the science is established enough that scientists can establish causal connections almost immediately. At the other end are things like tropical cyclones, rare and complex enough to elude current methods.
Yesterday, 50 years ago, Lyndon B. Johnson received a warning about the effects of climate change—the first of many to be issued to US presidents. Since that day, the discipline of climate study has been focused on large-scale effects of greenhouse gases: observing trends, establishing effects, making predictions. Those predictions—higher temperatures, stronger storms, yada yada yada—are familiar now. But mostly missing was any formalized way to look at climate change the other way; to identify a particularly nasty weather event and ask whether it was caused by climate change.