The fossil-fuel divestment movement has been on a roll lately to the tune of $50 billion, but one of its biggest successes happened last month: The world's most profitable oil company squirmed. Exxon Mobil's vice president of public and government affairs published a critique of divestment that concluded by...

California may be famous for its beaches, but what really defines the state's geography are its many mountain ranges (and I'm not just saying that because the Sierra Club took its name from one of them). Last Friday, President Obama permanently protected one of those mountain ranges -- the San...

Exactly 54 days after Lisa B. Nelson, the new CEO of the American Legislative Council (ALEC), started her job, Eric Schmidt, the chairman of Google, dropped the bomb: Google wanted out of its relationship with ALEC. "That was some sort of mistake," Schmidt said on The Diane Rehm Show when...

You shouldn't have to worry that installing a new hardwood floor in your kitchen will rob Siberian tigers of their home. Since 1900, we've had a law in this country, the Lacey Act, that prohibits trade in wildlife, fish, and plants that have been illegally taken, possessed, transported, or sold....

Back in March, I wrote about the Keystone XL "it's not about the pipe," saying that any rejection of new tar sands pipelines serves the purpose of keeping this dirty oil in the ground. Some good news from last week proves the point that I and others have been making....

If anyone doubted the existence of a mighty climate movement in this country, then the sight of more than 400,000 determined, joyful, vociferous people marching through midtown Manhattan in the People's Climate March in New York City last Sunday has set them straight. Even for those of us who...

We're right in the middle of Wilderness Week, and this year it's a special one because we just celebrated the 50th anniversary of the Wilderness Act -- which is still a high-water mark for the protection of our most precious wild places. On Wednesday night, I attended a big...

I've long known how wasteful, destructive, and dangerous the process of extracting oil from tar sands is. To get one barrel of oil, you have to dig up four tons of dirt and rock. Beautiful old-growth boreal forest becomes a wasteland. And that single barrel of oil? It creates three...

This most recent Labor Day has given us an opportunity to come together and recognize the working Americans who are on the front lines, responding to and solving the climate crisis.

We want to honor the first responders who stayed on the job for days and nights through and...

For the eighth year in a row, Sierra magazine has dedicated a big chunk of its September/October issue to higher education. So why is the "Cool Schools" issue such a big deal? I'll give you a hint: It's not because of the schools.

Over the last few years, I've...

With a couple of decisions in 2001 and 2006, the Supreme Court managed to break the Clean Water Act by calling into question what Congress meant by "the waters of the United States." The existing law had been working just fine for almost 30 years. When the Clean Water Act...

Wow! I was confident that people would turn out to support the Environmental Protection Agency's Clean Power Plan at last week's public hearings in Pittsburgh, Atlanta, Denver, and Washington, D.C., but I wasn't counting on a success this big. Advocates for clean air and cleaning up carbon pollution made their...

Last year, about 900,000 people marveled at the majestic old-growth redwoods of Muir Woods. But if President Theodore Roosevelt had not saved those trees by declaring a national monument, people would be admiring a municipal reservoir rather than the majestic Cathedral Grove.

The importance of national monuments was on our...

No matter how much I love my job, being away from Mary and the kids while I travel for work is always tough. Even on a fantastic trip like the one I took to the Arctic last month, I constantly catch myself wishing they could be there to see it...

Does doing something two years in a row qualify as a "family tradition"? If so, this is shaping up to be a great one. Once again, my wife Mary and I have packed the tent, the camping gear, the bug spray, and, oh yeah, our ever-intrepid kids into the minivan...

At the most basic level, the cause of climate disruption is obvious: a rise in heat-trapping gases in our atmosphere because we are burning so much coal, oil, and natural gas around the world. But this basic cause and effect aspect of climate disruption is only part of the equation....

You might want to save this date: September 21. Here's why.

Activists working to address the climate crisis have been cautiously cheering President Obama this year -- for telegraphing that he's likely to reject the Keystone XL tar sands pipeline and for the Clean Power Plan, an important set...

In his 19th-century curmudgeon's classic, The Devil's Dictionary, Ambrose Bierce defined a plan as "the best method of accomplishing an accidental result." When the EPA released its "Clean Power Plan" this month for reducing carbon pollution from power plants, the agency was clear about the results it expects by 2030:...

I was honored to be invited to speak to the United Auto Workers in Detroit at their convention this week. Even though the Sierra Club and the UAW have been working together for years, some people don't know we're natural allies.

Here are some other things you might not know...

For more than a century, presidents have been using the Antiquities Act to save our national treasures, and President Obama's just-announced designation of the Organ Mountains-Desert Peaks National Monument in southern New Mexico shows exactly why this law is so indispensable.

At nearly 500,000 acres (making it by far the...