A thick haze of smog has descended on parts of northern China, pushing pollution to more than 20 times what the World Health Organization considers a safe limit.
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In Hebei, a province bordering Beijing to the north, concentrations of pollutant particles called PM2.5 reached upwards of 500 micrograms per cubic meter, according to Beijing's air quality index. The WHO's recommendation for maximum healthy exposure is 25 micrograms.
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According to the U.S. State Department's air quality guide, levels of PM2.5 between 301 and 500 micrograms are considered hazardous to health and constitute a "serious risk of respiratory effects in the general population," while anything above 500 is literally off the charts.

Most U.S. cities have a PM2.5 concentration of 20 or below.

This country has made real progress since the crisis six years ago. The fact is, more Americans are working. Unemployment has come down. More Americans have health insurance. Manufacturing has grown. Our deficits have shrunk. Our dependence on foreign oil is down, as are gas prices. Our graduation rates are up. Our businesses aren't just creating jobs at the fastest pace since the 1990s. Our economy is outpacing most of the world.

But we just gotta keep at it until every American feels the gains of the growing economy where it matters most, and that’s in their own lives.

Obviously, much of that will take action from Congress. And I’m eager to work with the new Congress to make the next two years as productive as possible. I’m committed to making sure that I measure ideas not by whether they are from Democrats or Republicans, but whether they work for the American people.

And that’s not to say that we won’t disagree over some issues that we’re passionate about. We will. Congress will pass some bills I cannot sign. I’m pretty sure I’ll take some actions that some in Congress will not like. That’s natural. That’s how our democracy works.