03/11/2011 06:18 pm ET | Updated May 25, 2011

Rainforest, USA

Last week, conservationists won a big victory when a federal judge overturned the Forest Service's exclusion of the Tongass National Forest in Alaska from the Roadless Rule. That means that millions of acres of old-growth trees won't be cut and some of the most beautiful and pristine wilderness in America will, for now, stay that way.

The Sierra Club has been working to protect wildlands like the Tongass for more than 100 years now -- it's in our organizational DNA. And, without a doubt, many of our biggest successes have been in Alaska. But the Tongass National Forest also plays a crucial role in a more recent Club priority: avoiding climate catastrophe. That's because the Tongass is one of the largest remaining temperate rainforests in the world.

Of course everybody knows about the great tropical rainforests in the Amazon, Southeast Asia, and central Africa. But it's not the location that makes a rainforest -- it's the rain. And, as anyone who's ever been to Seattle knows, the tropics don't have a monopoly on rain. Much of the Pacific Northwest is -- or once was -- rainforest habitat, stretching in a thin band from Northern California, up through British Columbia into Alaska.

Rainforests -- regardless of where they're located -- contain incredible biodiversity, from the butterflies of the Amazon to the brown bears of the Tongass. Less apparent is that they also store enormous amounts of carbon, which is released into the atmosphere when those forests are mowed down. In fact, the Intergovernmental Panel on Climate Change has estimated that deforestation is responsible for almost 20 percent of global greenhouse gas emissions.

It turns out that temperate rainforests, like the Tongass, actually store more carbon per acre than their tropical counterparts. More than a third of these rainforests are in North America, and the biggest, by far, is the Tongass. In fact, by itself, the Tongass accounts for more than one-third of all the remaining old-growth, temperate rainforest habitat in the world.

Sadly, rainforests aren't just threatened by logging, mining, and oil and gas companies but also by rising temperatures around the world. Recent droughts in the Amazon have put countless species at risk. The fires raging once again in Indonesia are dumping ever more carbon into our atmosphere.

The good folks at Rainforest Action Network know this best: We can't protect rainforests unless we stabilize our climate. But we can't stabilize our climate unless rainforests are protected. The health of our forests and that of our climate are deeply intertwined. Or, as John Muir put it: "When we try to pick out anything by itself, we find it hitched to everything else in the Universe."