Elizabeth Shogren

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.

Canadian researchers have used the mud at the bottom of lakes like a time machine to show that tar sands oil production in Alberta, Canada, is polluting remote regional lakes as far as 50 miles from the operations.

An increasingly large share of U.S. oil comes from Canada's tar sands. There are environmental consequences of this development, but until recently, Canadian regional and federal governments left it to the industry to monitor these effects.

An east Texas landowner was so determined to block the Keystone XL pipeline from coming through his forest that he took to his trees and built an elaborate network of treehouses eight stories above the ground.

"It popped into my head a long time ago, actually," says 45-year-old David Daniel. "If I had to climb my butt on top of a tree and sit there, I would. It started with that."

It turned out to be Daniel's last stand in a long battle against the Keystone XL, a pipeline project that would bring oil from Canada all the way to refineries in the Texas Gulf Coast.

The air reeks so strongly of rotten eggs that tribal leader Wes Martel hesitates to get out of the car at an oil field on the Wind River Reservation in Wyoming. He already has a headache from the fumes he smelled at another oil field.

Transcript

AUDIE CORNISH, HOST:

From NPR News, this is ALL THINGS CONSIDERED. I'm Audie Cornish.

ROBERT SIEGEL, HOST:

And I'm Robert Siegel.

Already more than a million people from Maine to Virginia have lost electricity because of the storm. And in one case, as we heard a few minutes ago, the utility Consolidated Edison took the unusual step of cutting off power to parts of lower Manhattan. By the time the storm is over, more than 10 million homes and businesses in the eastern U.S. could lose electricity. That's according to the utility industry.

In previous elections, candidates from both parties have campaigned on pledges to be environmental presidents. This time, neither candidate is talking much about cleaning up the air or protecting scenic lands.

Instead, the debate has focused on whether and how much environmental regulations hurt businesses, especially the energy industry.

Mostly it's been GOP candidate Mitt Romney criticizing President Obama for what he sees as overzealous environmental regulations that strangle the economic recovery.

Environmental Rules

President Obama named a new national monument on Friday: Chimney Rock in southwestern Colorado. With two sandstone spires soaring from a mesa, not only is Chimney Rock a spectacular place; it also provides a fascinating glimpse into the ancient people who lived in that region more than 1,000 years ago.

Reducing greenhouse gases and saving the polar bears tend to dominate discussions on climate change. But to the booming world population, one climate change issue may be even more pressing – hunger.

A new report by a leading international relief agency warns that climate change will increase the risk of large spikes in global food prices in the future, and lead to more hungry people in the world. That's because extreme weather like droughts, floods and heat waves are predicted to become much more frequent as the planet heats up.

Wind and solar get lots of attention, but another kind of renewable power actually creates more energy in our country --wood. The state of Massachusetts on Friday decided that these plants aren't green enough to get some special breaks.

Sometime in the next few months, David Daniel probably will have to stand by and watch as bulldozers knock down his thick forest and dig up the streams he loves.

His East Texas property is one of more than 1,000 in the path of a new pipeline, the southern stretch of what is known as the Keystone XL system.

For years, Daniel has tried to avoid this fate — or at least figure out what risks will come with it. But it has been difficult for him to get straight answers about the tar sands oil the pipeline will carry, and what happens when it spills.

A couple of thousand years before the Egyptians preserved some of their dead, a much simpler society made the first known mummies.

The Chinchorros, the first mummy makers, lived about 7,000 years ago in South America, on the coast near the border between modern-day Peru and Chile. The desert area where they lived was so dry, dead people turned into mummies naturally.

The next time you take a sip of your favorite wine, you might want to make your first toast to hornets. Or, more precisely, European hornets and paper wasps.

NASA may have retired its shuttles, but it has its sights on sending astronauts deeper into space than ever before.

These voyages are years away, but on Monday, astronauts are heading underwater to take part in a simulation that will help them figure out how they might explore one possible new destination: a near-Earth asteroid.

Gaby Petron didn't set out to challenge industry and government assumptions about how much pollution comes from natural gas drilling.

She was just doing what she always does as an air pollution data sleuth for the National Oceanic and Atmospheric Administration.

"I look for a story in the data," says Petron. "You give me a data set, I will study it back and forth and left and right for weeks, and I will find something to tell about it."

Living in the middle of a natural gas boom can be pretty unsettling. The area around the town of Silt, Colo., used to be the kind of sleepy rural place where the tweet of birds was the most you would hear. Now it's hard to make out the birds because of the rumbling of natural gas drilling rigs.

The land here is steep cliffs and valleys. But bare splotches of earth called well pads are all over the place.

"That's the one I'm worried about because it just went in," says Tim Ray.

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