The financial crisis made Americans less worried about climate change. The Democrats’ attempt to pass sweeping climate legislation in 2009 and 2010 probably reduced Americans’ anxiety level as well, as paradoxical as that may sound. But now Americans are getting more worried again.

About 69 percent of adults say that global warming is either a “very serious” or “somewhat serious” problem, according to a new Pew Research Center poll, up from 63 percent in 2010. The level of concern has still not returned to that of a decade ago; in 2006, 79 percent of adults called global warming serious.

It’s impossible to know exactly why concern about the climate fell — and why skepticism that global warming was real increased — starting around 2008. Both economics and politics probably play a role. The financial crisis and recession made Americans more worried about the immediate condition of the economy, rather than about the long-term condition of the planet.