It’s hard sometimes to ignore climate deniers: They’re so wrong! About everything! But the biggest impact they seem to be having is just that: annoying environmentalists. Denialist campaigns have had little influence on the 30 percent of people who are skeptical about climate science, ABC News reports. The one thing that does change those people’s opinions? The weather.

This insight into the brains of “people who have low confidence in scientists” — the same people who are likely to believe in global warming one year and not the next — comes from Jon Krosnick, a Stanford University professor who studies public opinion on climate and energy. According to his research, belief in global warming doesn’t vacillate all that much in response to denialists’ work. But a year of extreme weather can gin up belief in climate change.

As GristList noted last week, people really don’t have any rational reason for believing in climate change or not. If weird weather makes people believe, so does sitting in a particularly warm cubicle. But given the crazy weather America’s experienced this year — slews of record highs, blizzards in April, snow in Seattle — it might be a good time for politicians to start talking about climate change again. For whatever totally irrational reason, people might actually be worried about it for, oh, the next nine months or so.

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