Stephen Gardiner expresses the inequalities:

At the international level writers on justice often point out the sharp differences in national emissions levels.  For example, the USA and China each have total carbon emissions that are roughly four times those of India, and more than eighteen times those of Bangladesh.  Similarly, the average American’s emissions are roughly equal to those of nearly five Chinese, fifteen Indians, and sixty-six Bangladeshis.  Moreover, since, at the present time, such differences appear to be strongly correlated with economic prosperity, much is at stake in deciding how to distribute future emissions, at least in the near-term.

Further information from The Guardian’s Data Blog (2011):

• China emits more CO2 than the US and Canada put together – up by 171% since the year 2000
• The US has had declining CO2 for two years running, the last time the US had declining CO2 for 3 years running was in the 1980s
• The UK is down one place to tenth on the list, 8% on the year. The country is now behind Iran, South Korea, Japan and Germany

Graphic via Stanford Kay at Pacific Standard Magazine.