Nathan Myhrvold. (Photo by Red Maxwell.)

Yesterday, I wrote about a new peer-reviewed paper from inventor Nathan Myhrvold and climate scientist Ken Caldeira. It found that, if there is to be any hope of staying in the zone of climate safety (or at least semi-safety), the transition to carbon-free energy must begin immediately and cannot include any merely "low carbon" sources like natural gas.

I sent Myhrvold a few follow-up questions. Here are his responses, lightly edited.

Chief Judge David Sentelle.

Cross-posted from ThinkProgress Green.

In 2009, the U.S. Chamber of Commerce called for the “Scopes monkey trial of the 21st century” to question the scientific fact of human-made climate change.

Tuesday, the U.S. Court of Appeals for the District of Columbia began consideration of a landmark case that consolidates a series of challenges to Environmental Protection Agency’s (EPA) 2009 finding that greenhouse gases are a threat to public health and welfare and its related rule-makings. The cases, brought by energy companies, industry front groups, Gov. Rick Perry (R-Texas), and others, seek to stop the EPA from regulating greenhouse pollution. Their legal argument is that climate science is a hoax.

But the three-judge panel’s questions and comments during the first day of oral arguments showed enormous skepticism of the industry arguments. Acknowledging that by law, the panel must show deference to the EPA’s finding, the chief judge told one of the challenger’s lawyers: “You seem to be asking us to determine that the EPA is incorrect, but that is not the standard,” and even that “would not be enough to win the case for you.” Other arguments were similarly pooh-poohed by the panel.

Old buildings get a fresh look during the Pittsburgh Festival of Lights. (Photo by Richard Dudley.)

Last month, I spent a glamorous, fun-filled, sawdust-flavored week in the city I know best as my hometown's rival: Pittsburgh, enemy of Clevelanders everywhere. As an AmeriCorps member with Rebuilding Together -- a national nonprofit that renovates and repairs owner-occupied homes for low-income homeowners -- I was obligated to attend a workweek celebrating the legacy of Martin Luther King, Jr, and his commitment to service. I expected to end the week with great memories and a sense of accomplishment; I didn't expect to fall in love with the city of Pittsburgh along the way.

Our work was in the Homewood neighborhood, separated from wealthy areas like Shadyside and Squirrel Hill by an elevated busway. Cut off from the rest of the city, the early-20th-century houses dotting Homewood's genteel streets have blighted and declined in value as residents who could afford to leave moved out. Pittsburgh has shared the Rust Belt's general population loss, and impoverished neighborhoods like Homewood have been hit especially hard.

In the corner of a large, dim warehouse inside the Port of Oakland, Edel Gaingalas swings a hammer into a piece of wood. She’s looking for larvae -- the wood, pried off a shipping crate, is riddled with holes bored by insects who chewed their way inside looking for a home, but every one she's found so far is dead -- killed by the mandatory fumigation at the port of origin. Before the day is out, she'll find a live longhorned beetle larva, and the whole shipment will be sent back to China.

Like many of the people in this warehouse, Gaingalas used to work at the airport, in the international terminal of San Francisco-Oakland (SFO). She went through people’s luggage all day. Now, as a U.S. Customs and Border Patrol (CBP) agricultural specialist, she mostly hunts for bugs, though she finds the occasional plant as well -- like the time she found two rare orchids hidden inside a piece of furniture being imported from Asia. But she and CBP chief supervisory officer and public relations liaison Edward Low aren't strangers to bizarre customs discoveries: Low rattles off a list of things found in SFO Airport luggage with the practiced air of a man who gets asked this question a great deal. “A cow intestine with the grass still in it,” says Low. “A human hand stuffed with straw. Penises galore. Pick an animal -- we’ve found its penis in someone’s luggage."

Activists have succeeded in getting Chicago Mayor Rahm Emanuel to shut down the city's two coal plants -- one of them by the end of the year. That doesn't mean the city is off coal power entirely, of course, but banishing coal plants from within the city limits will have a massive effect on urban health.

As Philip Radford wrote here on Grist last year, pollution from the Windy City's coal plants costs tens of thousands of lives:

Every year, the toxic pollution that spews from the smokestacks of America’s coal-fired power plants kills between 13,000 and 34,000 people, according to studies by the Clean Air Task Force and Harvard University. That staggering figure doesn’t include the carbon pollution -- one third of all U.S. emissions -- that is driving the planet into runaway climate change.

One of the cool things about natural history museums is that they show you how nature has changed over time, adapting to volatile conditions and extreme challenges. And nothing is more volatile, extreme, or challenging than the human race, so it makes sense that there would be a museum to chronicle just how much we’ve messed with plants, animals, the climate, and in general the world around us. The Center for PostNatural History, opening this week in Pittsburgh, is that museum.

A man works his plot in the chinampas of Mexico City. (Photo by Eneas De Troya.)

Chinampas, or floating gardens -- small artificial islands full of crops, built up on shallow lake beds -- once sustained the Aztec capital of Tenochtitlan, producing multiple harvests every year. They still exist in Mexico City, feeding its rural citizens -- for now.

William D. Nordhaus -- economist, Yale professor, serious person -- has taken to a serious publication, The New York Review of Books, to put the smackdown on climate skeptics.

The back story: Nordhaus has done working analysis of the economic impacts of implementing climate policies. In that awful Wall Street Journal op-ed we wrote about in January, a group of skeptics cited that work as proof that the country should do exactly nothing in the next 50 years to fight climate change. In his new article, Nordhaus approaches this and other claims with, as he says, "a cool head and a warm heart." But eventually he just has to tell them “you know nothing of my work.”

Read and learn from all his responses to skeptics' arguments, but for the juicy bits, skip to item six. Here is what Nordhaus has to say about skeptics' interpretation of his work:

Photo by Jeremy Cusker.

Running a library is easier than you think. Forget the degree in library and information science and the carefully chosen prudish getups with easy-pull ripcords that turn them into sexy outfits. All you need is a box on a stick and a bunch of books to set up a Little Free Library, a front-yard stash that lets you share your love of reading with the community.

Photo by Christopher Elliott.

This is the Senator, the largest pond cypress in the U.S. and, at 3,500 years old, the fifth-oldest individual tree in the world. Or anyway, this was the Senator, because on Jan. 16, the Florida tree burned from the inside out.

Authorities initially ruled out arson, saying that friction or smoldering lightning damage may have started the fire. But they've now ruled it right back in, arresting 26-year-old Sara Barnes for lighting the Senator on fire while sitting inside it doing meth.