Organizers called it the largest climate rally in U.S. history, and it was. Depending on who you ask, there were 30,000, 40,000, even 50,000 people in Washington, D.C., Sunday to lobby for political action on climate change. Depending on who you ask, the tone was joyous or righteous. And depending on who you ask, those 30,000, 40,000, even 50,000 people were giving President Obama an angry demand, a stern but friendly prodding, or the "support he needs" to take action.

350.org, the Sierra Club, the Hip Hop Caucus, and a comprehensive list of basically anyone in the U.S. who cares about climate change joined with politicians, investors, indigenous peoples, and an assortment of celebrities (can't have a climate rally without some celebs!) to rally and lead a march on the White House Sunday afternoon, calling for an end to politics and policies that are cooking our planet to death. For all the serious stuff, it was also a party -- chants for justice were mixed in with mini dance parties to pop music. But for all the Gangnam Style, there was an overwhelming sense that, while this rally was a glorious show, it was also indicative of just how bad things have gotten.

"We have a very entrenched system that's going to really require us to work together for a vision of people, peace, and the planet," the Green Party's Jill Stein said in an interview. "We are here for the long haul."

From fracking and coal to factory farming, activists called for an end to all the little things that are adding up to climate meltdown. But mainly today we were here because of the Keystone XL pipeline -- the long-embattled project to pump vast quantities of tar-sands oil from Alberta to the Gulf of Mexico, halted a year ago by President Obama and up for a final decision this spring.

Dear America,

How are you? We are fine. It’s been a bit warmer than usual up our way. But not too bad, considering.

I wanted to check in with you about the Keystone XL pipeline proposal that many of you seem to be rather upset about, and actually ping you for a bit of neighborly advice. While some of us on this side of the border really want Secretary Kerry to give Keystone the thumbs-up, many of us are pretty cool on the idea.

The truth is, just beneath our mild-mannered veneer, we Canadians are a tormented people. Here’s why.

Unlike you -- with your Netflix, and Apple, and Facebook, and Boeing, and General Electric and so on -- we have a resource economy. Since our early days as the global leader in the beaver-pelt industry, we've cut down trees, and dug up rocks, and pumped stuff out of the ground, and sold it to you -- and others -- so you could turn it into more useful things like furniture, appliances, houses, suburbia, and so on.

Today, thanks to our oil sands, our fossil fuel sector is going gangbusters. In 2010, energy accounted for 6.8 percent of Canada’s GDP, with oil and gas contributing roughly half of that amount. This is in large part thanks to you. Even without Keystone XL, we are already your No. 1 supplier of imported petroleum — we more than double Saudi Arabia's contribution.

Fossil fuels literally keep the lights on in these parts, put bread on the table for hundreds of thousands of us, and provide critical government revenue that we have come to depend on for hospitals, schools, and other social services. But we’re just starting to realize the growing risk and uncertainty associated with this economic model.

Which is why we’re so ... conflicted.

The big President's Day rally on the National Mall is more than a Keystone pipeline protest. It's a statement of principle for climate action.

After a year of unprecedented destruction due to weather extremes, the climate fight is no longer just about impacts in the future. It’s about physical and moral consequences, now. And Keystone isn't simply a pipeline in the sand for the swelling national climate movement. It’s a moral referendum on our willingness to do the simplest thing we must do to avert catastrophic climate disruption: Stop making it worse.

Specifically and categorically, we must cease making large, long-term capital investments in new fossil fuel infrastructure that “locks in” dangerous emission levels for many decades. Keystone is a both a conspicuous example of that kind of investment and a powerful symbol for the whole damned category.

It’s true that stopping a single pipeline -- even one as huge and odious as Keystone -- will not literally “solve” climate disruption. No single action will do that, any more than refusing to sit on the back of a single bus literally ended segregation. The question -- for Keystone protestors as it was for Rosa Parks -- is whether the action captures and communicates a principle powerful enough to inspire and sustain an irresistible movement for sweeping social change.

Climate scientists have estimated that, in order to avoid runaway global warming, the world would need to cut its carbon emissions roughly in half by 2050. Since emissions in developing countries like China and India are still rising fast, meeting this target would require developed nations to aim for a figure more like 80 percent. When you consider that the United States, the largest polluter in the developed world, has no real strategy in place to achieve that -- and that no binding international agreements appear to be on the horizon -- the goal can start to sound nigh impossible.

The task is so intimidating that even serious people are starting to entertain extreme-sounding geoengineering ideas like flying business jets into the stratosphere and spraying sulfuric acid all over the place to try to deflect sunlight before it reaches the Earth. Others reckon it’s already too late to prevent catastrophic warming -- we’ll have to build sea walls and hope for the best. President Obama alluded to a possible cap-and-trade system in Tuesday’s State of the Union address, but few believe such a sweeping policy would pass Congress.

Yet in a report released on Thursday, the nonprofit Urban Green Council makes the case that the country’s largest population centers needn’t rely on a federal breakthrough. Specifically, the 51-page report, titled “90 by 50,” finds that New York City could slash its emissions by a whopping 90 percent by 2050 without any radical new technologies, without cutting back on creature comforts, and maybe even without breaking its budget.

That’s a far more aggressive target than even the city’s own relatively ambitious goal of reducing emissions by 30 percent by 2030. How is it possible? The strategy has plenty of familiar components -- electrifying the transit system, converting to renewable power sources. But it all hinges on one seemingly mundane yet surprisingly potent move: retrofitting almost every building in the city to keep the heat in during the winter and out during the summer. In a nod to Rudy Giuliani, Bill Bratton, and James Q. Wilson, I’ll call it the “triple-pane-windows theory” of greenhouse-gas reduction.

Congressional Republicans, like middle-school English teachers, are mad that people don't think they're cool. In quiet moments in institutional restrooms, they look into mirrors for a bit longer than normal, hands under the faucet, leaning in. "What is it?" they wonder, eyes scanning their faces. That's when someone else walks in. "Hey." "Oh, hey," the Republicans reply, eyes dropping, hands washing each other vigorously.

Like many of those unsteady educators, the GOP has decided to do something about its popularity problem. Middle-school teachers buy sports cars and new jeans. Republicans try to develop new messaging. Politico outlines the GOP's three new rules. Let us assess them.

Rule one: Stop talking like the world is going to end. Budgetary politics is important to the GOP, but voters are going to stop voting for a party that talks about gloom and doom around the clock.

“I think that we need to make being fiscally conservative cool,” said Rep. Candice Miller (R-Mich.), chairwoman of the Administration Committee and a close ally of Majority Leader Eric Cantor.

Yes. Stop talking like the world is going to end! You know how the Republicans are always like, "Oh, man, this climate change thing could really be apocalyptic and we're not doing anything about it," etc., etc. Stop doing that, Republicans!

And Rep. Miller has a great idea. A great idea. Make fiscal conservatism cool! Why didn't you guys think of that before? I mean, I know that in 2005, someone presented Cheney with "Operation: Shades" which would have put that plan into motion and he didn't jump on it, but why didn't you do it once he and the other guy got out of office? Honestly, if you started now, you could have fiscal conservatism lookin' cool by April. It's like Hawaiian shirt day at Initech. Mix it up, and you'll get the kids' respect.

This is interesting: Pipeline company Enbridge wants to turn a natural-gas pipeline in the Midwest into a crude-oil pipeline. From The Globe and Mail:

The latest proposal would redeploy a variety of existing pipelines, including part of Energy Transfer’s Trunkline natural gas system, as well as Enbridge’s new Southern Access Extension, which is under development. …

The proposal is one of several initiatives being considered to move more crude from the U.S. Midwest and Canadian Prairies to refineries along the coast of the Gulf of Mexico.

Canadian crude is currently being sold at a bigger discount than usual because of a lack of pipeline capacity and growing supplies from North Dakota and other states that are expanding output using advanced drilling methods.

That "lack of pipeline capacity" from the north will also be discussed this Sunday in Washington.

Perch are shy. They like to band together for protection, swimming together in schools the way nerds all share the nerd table in the high-school cafeteria. But now that lots of people are taking anti-anxiety drugs and their drug-laced pee has ended up in waterways, perch are acting differently, in ways that suggest they too have been mentally affected by these drugs. They've gotten cooler. They like to do stuff alone. Hunting, swimming, all the other perch stuff -- they just like to fly solo.

Hi, this is Bob Perciasepe. I'm honored to serve as acting administrator of @epagov

— Bob Perciasepe, EPA (@EPAadm) February 15, 2013

I'm sorry, who? I mean, nice to meet you, Bob! Welcome aboard, I guess.

As fans of the "United States Government" may know, EPA Administrator Lisa P. Jackson recently resigned her position. The president has not yet identified a pick to succeed her -- though there is some speculation that he might select Gina McCarthy, the agency's assistant administrator for air. And even once selected, that pick would have to be confirmed by the Senate. And so: Bob Perciasepe. (His last name is pronounced per-spih-CAY-shus, probably.)

Because I am a journalist, I Googled Mr. P. He has a Wikipedia page! He grew up in Westchester County, near New York City, went to school at Syracuse and Cornell, and served as Baltimore's city planner. Eventually, he became deputy secretary of Maryland's Department of the Environment, and then the state's secretary of the environment. In 1993, Bill Clinton appointed him to the EPA's office dealing with water. In 2009, Obama made him deputy administrator of the EPA.

Last week, reporter John Broder of The New York Times wrote an account of his road trip from Washington, D.C., to Milford, Conn., in Tesla's new all-electric Model S sedan, using the two Superchargers that the company has set up along the route. Broder says he got less range than advertised, lost a bunch of range overnight inexplicably, and ran out of power on his last leg. Elon Musk, CEO of Tesla, published a response to the story, effectively accusing Broder of journalistic malpractice.

Broder responded to Musk, and then responded again. Rebecca Greenfield at the Atlantic Wire also responded, charging that Musk hadn't established his case against Broder. TechCrunch weighed in. Twice. Also GigaOm. Also Boing Boing. Even Gawker piped up. And of course our own Philip Bump.

This seems like an awful lot of attention devoted to the precise performance characteristics of this particular vehicle on this particular trip. The Tesla S has been extensively and mostly positively reviewed in lots of other outlets (including the NYT itself). It's pretty well-established what it can and can't do. What really seems to be behind this, yet again, is a proxy argument over electric cars in general.

Kevin Bullis has the wisest comment on this dust-up, which is that it's dumb for an electric car to compete in the "drive a really long way without stopping much" category, precisely the place where gas cars currently retain an advantage. Broder made a bunch of mistakes, in retrospect. He could have done the drive without trouble if he'd planned better, been more careful, and gotten better advice from Tesla personnel. But American drivers are not accustomed to low speeds or careful planning in their long-distance driving and it will take time for those habits to change. It would make more sense to highlight the car's performance in applications where it shines, like commuting, which constitutes the vast bulk of Americans' actual travel.

If there were a war on coal -- which, sadly, there isn't -- it appears that the tide of battle has turned. Coal is making a comeback.

In an extensive article entitled "Coal Claws Back," the Rhodium Group, a think tank that assesses global trends, outlined the fuel's resurgence in the U.S. In short:

While the decline in coal-fired power generation, driven in large part by cheap natural gas, has helped reduce emissions to levels most policymakers and climate diplomats thought impossible absent economy-wide legislation, it looks as though it has just about run its course. Natural gas prices bottomed out in April of last year at $1.82 per MMBTU at Henry Hub, and have since climbed to above $3. While still low relative to the high gas prices that had become the norm before the shale boom took hold, this rebound has been enough to stop the bleeding for coal-fired power. Coal’s share of electricity generation increased from 33% in April to 42% in November, the most recent month for which public data is available, and industry consultancy GenScape estimates that coal’s share stabilized at these levels through January.

The picture is more clear in graph form.