This article originally appeared in The Huffington Post.

Many thanks to the Huffington Post and Betsy Taylor for helping to advance an absolutely critical debate on the urgent need for a strong, effective international climate change agreement.  In that same spirit, I’d like to clarify for HP readers the views of my organization, the Pew Center on Global Climate Change, which I’m afraid Betsy didn’t get quite right. (Click here to access the post by Betsy Taylor.)

First, the Pew Center “press release” that Betsy links to is not a press release, but rather an Associated Press story that quotes the Pew Center’s president, Eileen Claussen.  Betsy also links to a Washington Post story quoting me.  The stories quote us accurately but, as is invariably the case with daily dispatches, only partially capture the views and intent of the individuals quoted.  So please allow me to elaborate.

The Pew Center believes that, for the sake of the planet and future generations, our goal must be a ratifiable treaty establishing fair and effective commitments for all major economies.  We also believe it is critical that the UN climate conference in December 2009 in Copenhagen produce an agreement that moves us as close as possible to that goal.  How far we can get between now and Copenhagen will depend primarily on two things: how quickly Congress gets on with the job of enacting mandatory legislation to cap and reduce U.S. emissions; and how prepared other countries are to scale up their national climate efforts and translate them into international commitments.

The election of Barack Obama presents an historic opportunity to confront climate change at home and abroad.  We must do everything in our power to seize that opportunity.  But we also must be realistic.  If we set unrealistically high expectations – if we insist that the only “successful” outcome for Copenhagen is a full, final, ratifiable treaty – then we heighten the risk of a major failure that will serve only to set back the process and the politics.

Rather, we must allow for the possibility of an agreement in Copenhagen that, while short of a ratifiable treaty, can capture all the momentum that builds over the coming year and generate further momentum in the months beyond.  One possibility is an agreement that lays out the basic architecture of a post-2012 framework, the level of emission reductions to be achieved by developed countries collectively, the types of mitigation action to be undertaken by developing countries, and the types and level of support they can expect to receive.  Some might characterize this as pessimism.  In our view, it would in fact be a very ambitious outcome putting us within striking distance of a ratifiable treaty.  Far from a failure, it would be a striking success.

For those interested in more on the Pew Center’s perspective on this and other climate issues, please visit us at www.c2es.org.  We look forward to continuing this dialogue, and to a successful outcome next year in Copenhagen.

Elliot Diringer is Vice President for International Strategies at the Pew Center on Global Climate Change.