Everyone knows that our iPads, clothes, kitchen appliances, furniture—our entire lives, basically—are made in China. But everyone might not know the container ships that bring that stuff over to the U.S. are climate-destroying juggernauts. According to OnEarth, just one container ship emits as much sulfur oxide (the stuff that makes smog) per year as 50 million cars. Plus, shipping accounts for 3.5 percent of all GHG emissions, twice as much as aviation.

The good news is that air pollution rules are pushing container shipping companies to clean up their act. They're selling off their speedier, dirtier boats. They're looking into biofuels. They're spending more than a billion dollars on energy-efficient boats.

The best way to decrease these ships’ impact is, as with every similar pollution issue, for all of us to buy less stuff. But as long as many, many people crave iPads and Barbie dolls, the less pollution that goes into getting that stuff here, the better.

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