Elizabeth Shogren

At about 300 colleges across the country, young activists worried about climate change are borrowing a strategy that students successfully used in decades past. In the 1980s, students enraged about South Africa's racist Apartheid regime got their schools to drop stocks in companies that did business with that government. In the 1990s, students pressured their schools to divest Big Tobacco.

This time, the student activists are targeting a mainstay of the economy: large oil and coal companies.

Up until now, pipelines that carry tar sands oil have been treated just like pipelines that carry any other oil. But the Environmental Protection Agency now says that should change. That's because when tar sands oil spills, it can be next to impossible to clean up.

The agency made this argument in its evaluation of the State Department's environmental review of the Keystone XL pipeline project, which, if approved, would carry heavy crude from Alberta, Canada, to refineries in the United States.

A gluttonous predator is power-eating its way through reefs from New York to Venezuela. It's the lionfish.

And although researchers are coming up with new ways to protect some reefs from the flamboyant maroon-striped fish, they have no hope of stopping its unparalleled invasion.

Lad Akins has scuba dived in the vibrant reefs of the Bahamas for many years. But when he returned a couple years ago, he saw almost no fish smaller than his hand.

Amber Bartlett was waiting last Friday for her kids to come home from school. One of them called from the entrance to the upscale subdivision near Little Rock, Ark., to tell her the community was being evacuated because of an oil spill. Bartlett was amazed by what she saw out her front door.

"I mean, just rolling oil. I mean, it was like a river," she says. "It had little waves in it."

A group of environmentalists and drilling companies has crafted a truce of sorts over the rapid spread of natural gas production in the Appalachian Basin. Four major drilling companies and several environmental groups have agreed on 15 voluntary standards for cleaner drilling practices.

The practices of horizontal drilling and hydraulic fracturing — when companies inject water laced with chemicals deep underground to split open rock formations and get the gas to flow faster — are transforming the rural region in the Eastern U.S. into a sprawling industrial zone.

Environmentalists have a hope.

If they can block the Keystone XL pipeline, they can keep Canada from developing more of its dirty tar sands oil. It takes a lot of energy to get it out of the ground and turn it into gasoline, so it has a bigger greenhouse gas footprint than conventional oil.

Tens of thousands of protesters turned out on the National Mall Sunday to encourage President Obama to make good on his commitment to act on climate change.

In his Inaugural address from outside the U.S. Capitol, the president said: "We will respond to the threat of climate change knowing that the failure to do so would betray our children and future generations."

Just a few weeks later, next to the Washington Monument, Paul Birkeland was one of a couple dozen people holding a long white tube above their heads.

President Obama pulled out a surprise in his inaugural address on Monday. After barely mentioning climate change in his campaign, he put it on his short list of priorities for his second term.

"We will respond to the threat of climate change, knowing that the failure to do so would betray our children and future generations," he said. Today the White House had scant detail on what the president plans to do.

Modern scientists trying to understand climate change are engaged in an unlikely collaboration — with two beloved but long-dead nature writers: Henry David Thoreau and Aldo Leopold.

The authors of Walden and A Sand County Almanac and last spring's bizarrely warm weather have helped today's scientists understand that the first flowers of spring can continue to bloom earlier, as temperatures rise to unprecedented levels.

Just a few years ago, Georgia Power generated nearly three-fourths of its electricity with coal. Last year, for the first time, natural gas edged out coal, and just this week the company announced plans to close 10 coal-fired power generators within the next few years.

"We do recognize this is a historic event for our company. We've never announced this many closings at one time," says Mark Williams, a company spokesperson.

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