This post originally appeared on the Huffington Post

There were two scientific studies this week that set the ongoing Keystone pipeline battle in sharp relief.

One was a reminder of just how crucial this fight is. A secret report delivered to the Canadian government’s chief bureaucrat showed that changes in tarsands mining methods, which the industry claimed reduced the amount of carbon emissions, were actually “three times as emissions intensive” and that damage to the environment would be both “significant” and “irreversible.”

That’s one reason the EU moved closer last week to preventing the import of tarsands oil to Europe, and it helps explain why the White House continued to stand strong against Congressional efforts to force a permit for Keystone — as the president’s press secretary pointed out (in a pointed tweet) the administration’s new fuel efficiency standards for cars would save more oil than the pipeline could deliver in 45 years.

But the second study made clear to tarsands opponents — if it hadn’t been already — that this was only one battle in a much larger fight. A new study from a pair of British Columbia scientists shows that there’s a lot of carbon in the tarsands — but a lot more yet in the planet’s coal deposits.

If you burned all the tarsands we know about now, you’d raise the planet’s temperature more than half a degree — i.e., half again as much as the global warming we’ve already seen, which has been enough to make the seas 30% more acid and cut Arctic sea ice 40%. But if you burned all the coal we know about it, the temperature would go up 15 degrees.

<--break->At a certain point, I suppose, it doesn’t matter — most scientists think anything more than two degrees Celsius puts us into a zone of extreme danger, and we’re already halfway there. Fifteen degrees would be just gilding the lily. Still, it makes it clear that even if, as NASA’s James Hansen has said, burning the planet’s unconventional fuels like tarsands would mean it was “game over the for the climate,” stopping that burning won’t be enough. We also have to address the most obvious, conventional forms of energy — coal, especially. It was the first kind of fossil fuel we learned to burn, 300 years ago. And we’ve got to kick the habit.

Which is why, even as the political gamesmanship over the Keystone pipeline rages on (with the GOP at the moment making the absurd claim that this export pipeline will lower U.S. pump prices), we’ve got no choice but to take on other battles. has been embroiled these last weeks in the fight over a massive new coal plant in Kosovo; closer to home, plans were just announced for a truly massive new coal port in Washington State that would take eight mile-long coal trains a day from the Powder River Basin of Montana and Wyoming and ship them straight to China.

We’ve got to stop projects like this, just as we united to fight Keystone. In fact, we’ve got — as soon as possible — to stop fighting bad things one by one. We don’t have enough fingers to plug every hole in the dike; we need to change the basic underlying economics, by charging the fossil fuel industry for the damage carbon does in the atmosphere instead of just letting them continue to use the atmosphere as an open sewer for free.

The fact that there’s more coal than tarsands doesn’t change the math of the Keystone debate. As the scientist who did the study pointed out, this is “not a get out of jail free card” to the tarsands industry, and added that he also opposed the proposed Gateway pipeline to Canada’s Pacific coast.

But it is a powerful reminder that we don’t get to rest in a fight that we’re still losing, a fight that has many fronts but only one central tenet: the future of the earth depends on keeping carbon underground.

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