There’s some furious spin and skullduggery going on in the run-up to the Copenhagen talks on climate change next month.
Major countries are trying to strengthen their positions at the talks by casting themselves as heros and their rivals as villains.
So in the wake of Barack Obama’s pledge to fly to Denmark, Wen Jiabao promised yesterday that he would go to the talks as well.
And after the US announced a pretty low-ball offer of a 17% cut in carbon dioxide emissions by 2020, China came up with its own target: a 45% fall in "carbon intensity" in the same time period.
What does this mean? Carbon intensity is a measure of CO2 emissions per unit of GDP. So pledging to reduce intensity doesn’t mean that emissions will fall overall.
In fact, if Chinese GDP continues to grow at 8% a year until 2020, there would be around a 90% increase in carbon dioxide emissions over the same period. But the increase would be even higher without the pledge to reduce intensity.
It’s roughly saying that China is going to be more energy efficient going forward.
As a developing country, China doesn’t technically have to make any carbon reduction pledges, although it is pretty clear that as the world’s largest producer of carbon dioxide, China is a different sort of "developing" country from, say, Zambia or Fiji.
Fearful that China might win some hearts and minds with its statement, rival governments quickly began to lobby against China’s offer.
They pointed out that China had reduced its carbon intensity by 44% between 1990 and 2005 anyway, and that going forward, it would reach this target naturally anyway.
According to the Energy Information Administration, China’s carbon intensity was 7.98 tons per $1,000 of GDP. That figure steadily declined into the 1990s with improvements every single year until 2001, when it stood at 2.39 tons.
However, China’s rapidly expanding export sector then kicked in, and as China started producing goods for the rest of the world, its carbon emissions jumped.
Because China only made a small share of the profits on those exports, the majority of the money going to Apple or Nike, for example, than to the manufacturing factory, carbon emissions jumped faster than GDP. The intensity figure started rising from 2.39 to 2.85 tonnes in 2006.
In the 25 years from 1980 to 2005, China reduced its carbon intensity by 64pc. If you count back a decade, you get a 15.4pc reduction, as the curve flattened out.
The figures, however, are not trustworthy. No one can work out how China managed to achieve such startling reductions in the early 1990s.
What can be said is that in the long term, China has managed to reduce its carbon intensity by a similar amount as the one it has pledged, and that going forward it will reach the new target without breaking a sweat.
To hit the target, China will have to reduce intensity by 3% a year. It is already managing a 4% to 4.5% annual cut, and its energy efficiency targets are much more stringent than the new figure.
Analysts reckon Beijing should be at least halfway to the 2020 goal by the end of next year.
In short, it is a low-ball offer, just like the one from the US (coincidentally, the US pledge to reduce overall emissions by 17% by 2020 adds up to a reduction in carbon intensity of, wait for it, 45%).