While the statement may appear as a movement forward, we are concerned that it may, in effect, be a regression from what is required to make a meaningful contribution to meeting the challenges of climate change ... the long term goal is an empty slogan without substance.

Van Schalkwyk also joined by Brazil, China, India, and Mexico (which are together known as the G5, or the five largest developing countries), in a separate statement to call for much larger reductions than those agreed to by the G8. They also called on the G8 to exhibit better leadership: "It is essential that developed countries take the lead in achieving ambitious and absolute greenhouse-gas emission reductions."

Among the chief criticisms: The long-term goal of cutting emissions 50 percent by 2050 is well below the 80 percent below 1990 levels by 2050 that most scientists agree is necessary. The "goal" also lacks near- and mid-term targets that would preserve the integrity of the long-term goal. The G5 asked developed countries to commit to a target of between 25 and 40 percent below 1990 levels by 2020.

There's also no clear baseline for the cuts: Japanese prime minister Yasuo Fukuda said yesterday that the baseline for cuts is 2008 emissions levels. Then his spokesperson said later that "The issue of baselines was not discussed. These discussions should be taken up by the U.N." It remains unclear what emissions figure G8 nations are pledging to halve.

Then there's the ongoing problem in the developing countries that are major emitters of greenhouse gases, like China and India. The G8 statement calls for these countries to take "meaningful" actions to reduce emissions. But those countries maintain that since the developed world has historically been responsible for much of the emissions, they should be responsible for the majority of the effort to clean things up. And, of course, nations like the U.S. have resisted the idea of any global emissions pact that doesn't include China and India.

And, as the BBC helpfully points out, this "new agreement" is exactly the same goal that the leaders of the G8 and nearly 200 other countries signed on to at the original United Nations climate change convention in Brazil in 1992.