The latest iteration of climate talks came to a close in Cancun on Friday (Dec. 9) with some small steps forward, but without a binding treaty and no strengthened pledges to reduce greenhouse gases.

"Certainly, relative to expectations it was a very big success. Compared to what needs to be accomplished it falls woefully short," Joseph Romm, a senior fellow at the Center for American Progress, and editor of ClimateProgress.org, told LiveScience. "The situation is quite dire, and the science has gotten considerably more solid and alarming in the last year or two."

Talks in Copenhagen a year ago failed to produce a binding treaty to succeed the Kyoto Protocol, which, in 1997, required industrialized countries to reduce their emissions an average of five percent. (The U.S. never signed on.) As a result of this disappointment, expectations for Cancun were modest. [The Basics of the Cancun Climate Talks]

Two important accomplishments in Cancun included progress in creating a fund to assist developing countries and incentives to prevent deforestation, Romm said.

The Cancun Agreements also continued talks to extend the Kyoto Protocol, whose commitment period expires in 2012, and they quantified greenhouse gas reduction pledges made in Copenhagen.

However, these pledges provide only 60 percent of the greenhouse gas reductions needed to cap warming of the Earth's average surface temperature at less than 2 degrees Celsius (3.6 degrees Fahrenheit), according to estimates in a report by the United Nations Environment Program.

"There is nothing in the agreements I have seen changes the size of the gap as it was estimated in the UNEP report," said Beth Sawin, one of the lead authors of the report, and co-director of the nongovernmental organization, Climate Interactive.

The report calculates that, to keep global warming below this threshold, global emissions will most likely need to peak before 2020, and without an agreement from Cancun that includes stronger reductions, the world comes a year closer to that threshold.

"I would say that is worrisome," Sawin said.

Talks continue next year in South Africa from Nov. 28 to Dec. 9.

You can follow LiveScience writer Wynne Parry on Twitter @Wynne_Parry.