Climate leaders in both Congress and the United Nations are optimistic about making landmark progress on an international climate accord this year, but hopes that an agreement will be finalized in 2009 seem to be dimming.

Yvo de Boer, the U.N. climate chief, and Rep. Ed Markey (D-Mass.), chair of the Energy and Environment Subcommittee in the U.S. House, spoke to reporters on Thursday in advance of climate meetings that kick off in Bonn, Germany, this weekend. The two-week gathering — which will be the Obama’s administration’s first international climate summit — is intended to set the stage for the big climate negotiations in Copenhagen in December.

At a press conference earlier this week, President Obama stressed the importance of moving forward on climate legislation this year. “We’ll get it done,” he said. But administration officials are reportedly trying to tamp down expectations that a final climate treaty can be completed by the end of the year, suggesting that Obama may need an additional six months to get congressional buy-in.

At Thursday’s event, both de Boer and Markey expressed hope that major progress can be made this year even if a treaty is not finalized.

Markey reaffirmed that House leaders are doing their part to get a U.S. plan in place this year in preparation for Copenhagen, noting that draft climate legislation from his committee is expected to be released next week. The committee will begin discussing the bill after Congress’s April recess, and hold a vote on it before the May recess. “That is an ambitious schedule, but the urgency of the issue that threatens the planet requires us to give the issue that kind of attention,” he said.

Markey also argued that the Obama administration remains committed to the same goal. “The president said we will get it done. He wants a global warming and clean energy bill, and he intends to pursue it, and we intend to deliver it back to him,” he said. “So I think that people should have some confidence in that process.”

Still, said Markey, “A lot is left to be done here in the United States in preparation for becoming a, if not the, world leader on this issue.”

The big goals

For his part, de Boer outlined what he would define as successful results in Copenhagen, even if a treaty is not agreed upon. The talks must deliver clarity on near-term emissions cuts for both industrialized and developing countries, he said. Also, industrialized nations need to devote significant financial resources to help poorer nations invest in clean technologies and adapt to climate change, and parties need to establish a structure to ensure that those resources are deployed efficiently, effectively, and with the input of the developing countries.

If Copenhagen can deliver on those points, said de Boer, “we have a robust architecture for a resounding response to climate change at the international level.”

But de Boer emphasized that time is short to make even that much progress by the Copenhagen meeting. (If you want to see just how short, the U.N. Framework Convention on Climate Change is counting down with a ticker.) The Copenhagen talks are eight and a half months away, but world leaders only have six weeks of formal, on-the-ground negotiating time before then — two weeks in Bonn starting on Sunday, another two in Bonn in early June, and two weeks in Bangkok in late September and early October. “People really need to get down to serious work as of now,” said de Boer.

The UNFCCC released a document on March 17 that will guide talks among the 192 participating countries. It outlines ideas that have been brought to the table so far and fleshes out some areas of agreement and divergence among world leaders.

U.S. climate envoy Todd Stern will address the opening session of the talks in Bonn next week. The crowd will have high expectations, even if they know the road to a climate treaty will be bumpy.

“The new administration will be at the table for the first time as a full partner,” said de Boer. “I am sure that everyone will be very excited to hear what he has to say.”