Saying that "this is a crucial year for taking rapid and effective global action to combat climate change," leaders of the so-called G8 nations agreed today to take steps to keep the average global temperature from rising more than 2 degrees (Celsius).

In pursuit of that goal, President Barack Obama and the other leaders said in a declaration released a short time ago that:

We reiterate our willingness to share with all countries the goal of achieving at least a 50% reduction of global emissions by 2050, recognizing that this implies that global emissions need to peak as soon as possible and decline thereafter. As part of this, we also support a goal of developed countries reducing emissions of greenhouse gases in aggregate by 80% or more by 2050 compared to 1990 or more recent years. Consistent with this ambitious long-term objective, we will undertake robust aggregate and individual mid-term reductions.

As the Associated Press points out, the Bush administration had resisted setting such a temperature goal. The wire service also notes, though, that:

It remains only a target, however, and it is far from clear that it will be met, especially as China, India and other rapidly industrializing nations generate and consume more energy from coal and other sources.