Cross-posted from the Center for American Progress.

The world’s leading economic powers remain inactive in preventing an increase in the serious impacts of climate change.

While current impacts of climate change may not have reached alarming proportions, according to the Intergovernmental Panel on Climate Change that will happen soon enough if we do not take early action. What is causing increasing concern, as the December U.N. climate summit in Copenhagen draws ever nearer, is the continuing deadlock in political action to deal with this challenge.

There is clear consensus among those arriving in Pittsburgh this week for the G20 that climate change is our most pressing global problem. The leaders of 16 of these countries signed a declaration last July after the G-8 meeting in Italy acknowledging that temperatures should not be allowed to exceed 2 degrees Celsius and that, as a consequence, global emissions must be reduced 50 percent by 2050. But the IPCC had clearly concluded that to ensure this limit, global emissions would have to peak no later than 2015, a finding that both the G-8 and the G-20 failed to highlight. Nor do the negotiations leading up to Copenhagen reflect this imperative.

The interim U.N. meetings over the summer leading up to Copenhagen have not gone well. Still unresolved are fundamental differences between developed countries about whether the Kyoto Protocol should be continued or be abandoned altogether for an entirely new treaty. The document under discussion at the U.N. is some 200 pages of contradictory provisions from a variety of submissions from different countries. Practically every sentence contains bracketed language still needing debate and revision. The prospect of shaping this up into a coherent document by December, with only two more interim meetings to go, appears grim.

The greatest divide that remains, however, is between developed and developing countries. In the massive voting blocks that still dominate this process among 192 countries it appears that developed countries and developing countries are at an impasse. While it is true that developed countries carry the burden of historical responsibility, and must prove to be the first movers in mitigation, developing countries will become bigger emitters in the future; this intractable dynamic is proving unconstructive.

There is much at stake here. If leaders say they want to cooperate internationally, and then fail to do so, the whole credibility of action on climate change will be damaged in the minds of the public, which may retreat to defeatist pessimism or cynicism.

How can this be avoided? In our view, a way has to be found to nudge the whole debate onto a more positive track, where the discussions among the leadership of countries is focused on how collaboration can deliver a step change in the use of low-carbon technology and create jobs and new economic growth along the way.

The countries meeting in Pittsburgh represent more than 80 percent of global emissions; they must act together, in keeping with the principles of the U.N. Framework Convention on Climate Change. We suggest they emerge from their talks having agreed to what we might call a Pittsburgh Protocol: an informal agreement containing two elements.

The first part of the Pittsburgh Protocol would reaffirm a collective will to find solutions to the political divisions through negotiations under the United Nations. Coming from this group it would signal that meetings among smaller sets of countries can advance the U.N. agenda in a less adversarial manner.

The second part would focus on a series of mini-agreements that could be reached at or before Copenhagen and that could be sketched out in Pittsburgh. These should include more specific measures to cooperate on immediately available low-carbon technologies, collaboration on pilot projects to capture and store carbon emissions, new financing arrangements to help developing countries meet energy-efficiency goals and immediate support to slow down deforestation.

A high level group of finance ministers from among the G20 countries has already drafted three papers on the creation of new finance mechanisms to help pay for a global transition to a clean energy economy in advance of the Pittsburgh summit. These proposals must be advanced so that we can assess the amount of money that could be generated.

A new study from the Global Climate Network of think tanks, to which we belong, argues that development of climate change policies and low-carbon technologies promises to create a generation of new jobs. But this will only come to pass if governments are bold in their approaches to creating new markets.

The G20 is a good opportunity for leadership countries to pull in the same direction on creating a green economy. More importantly, given the short road to Copenhagen, it is now a critical opportunity. Let’s not waste this chance.