Climate discussions of late have focused a lot of so-called short-lived forcers. These are substances such as methane and black carbon that don’t stay in the atmosphere for all that long but trap a lot of heat while they’re there. Analysts use global warming potentials (GWPs) as shorthand to compare these gases with carbon dioxide. For example, over a 20-year period, methane traps 72 times as much heat as carbon dioxide, giving methane a 20-year GWP of 72. Read more »

Cheap natural gas has split the climate debate into two camps. One celebrates the development, emphasizing that natural gas cuts emissions when it replaces coal, and arguing that abundant gas reduces emissions as a result. The other bemoans the news, noting that inexpensive natural gas makes it tougher for zero-carbon energy to compete and arguing that this will ultimately result in higher, not lower, emissions. Read more »

I have a new note in the Journal of Geophysical Research (JGR) that I hope will be the last word in an increasingly tedious battle over an isolated but highly publicized methane leakage study that was published last year. I’ll explain what the note says in a moment, but first some background is in order. Read more »

In an exchange about the Keystone XL pipeline earlier today, NASA’s Gavin Schmidt made an important point: “Many things can raise the effective carbon price: tax, cap-and-trade, regulatory action (mercury standards, pipeline decisions etc)”. (I’ve taken the liberty to expand some twitter abbreviations.) That’s true. So what carbon price would blocking the Keystone XL pipeline be equivalent to? Read more »

A piece in Slate by Ray Pierrehumbert arguing that tight oil abundance is a myth is making the rounds. The essay makes some fair warnings against irrational exuberance when it comes to hundred year supplies, claims of endless energy independence, and complacency on climate change as a result of abundant natural gas. But the piece does at least as much to confuse as illuminate. Fortunately, that provides a good opportunity to look at a few important misunderstandings that frequently arise in discussions about U.S. oil. Read more »

President Obama surprised pretty much everyone when he spent a considerable part of his inaugural address talking about the need to confront climate change. It suggests a willingness to tackle the issue in ways that go beyond what was accomplished in his first term. Read more »

I have a new paper (PDF) in Climatic Change that explores the climate consequences of natural gas as a bridge fuel. [Update: The article is now behind a paywall. If you don't have access, you can download an unformatted pre-print version here.] Read more »

The annual United Nations (UN) climate talks are rarely a pretty sight. The typical script is fairly reliable. Negotiators typically arrive at each summit with mostly realistic goals. But diplomats and those who seek to influence them spend the first week or so ratcheting up demands and accusations, in part for leverage, but at least as much in order to make themselves look good and their adversaries appear villainous. Members of the media (if they’re paying attention) report that the talks appear set for disaster. Meanwhile, away from the spotlight, negotiators quietly hash through the substantive tasks at hand. Eventually, in the middle of the second week, higher level officials arrive. Occasionally, important differences prove impractical to resolve, and the summit collapses. Far more often, the parties cobble something modest together, apparently snatching victory from the jaws of defeat. Read more »

The annual United Nations climate talks got underway in Doha, Qatar on Monday.

In a piece for the CFR website, I walk through the issues on the table, and offer some thoughts on U.S. strategy. The title of the piece – “A Transitional Climate Summit in Doha” – is a pretty good summary.  After three years of high tension and high stakes summits, Doha will almost certainly be more mellow, though no climate conference would be complete without a few fireworks toward the end. Read the whole piece for more. Read more »

The past week has been huge for people who want to see the United States go big on climate change. First Hurricane Sandy vaulted climate change back into the public debate. Now the reelection of Barack Obama means that there will be someone in the White House who cares strongly about the issue. The combination creates an opportunity to press for climate action. Read more »