The climate change conference starting in Cancun Monday is doomed to failure. Many factors contribute to this, such as a healthy skepticism about how much should be spent to remediate climate change, but one alone guarantees failure: Chinese coal production and policy.

When climate change soared up the American agenda with the election of President Obama, those not swept up in blind optimism were doubtful China could be convinced to go along. The debacle of the Copenhagen summit last year finally brought the administration and its supporters back to reality.

Prior to Copenhagen, it was already clear that Chinese coal was an insuperable obstacle to an international agreement on greenhouse gases. The past year has made the situation that much starker.

In 2000, the official figure for Chinese coal production was 880 million tons. In less than a decade, it more than tripled to 2.96 billion tons for 2009. In the first quarter of this year, coal production jumped another 28 percent. China, which was a net exporter of coal as recently as 2008, was the world’s largest importer of coal in the first three quarters of this year and far more in the way of imports are on the way.

China is spending a good deal of money on “green energy” and it is constantly praised for doing so. The praise is somewhat strange: the supposed switch from “black” to “green” has done nothing at all to stop coal: production growth was faster in 2008 than 2007, despite the financial crisis, and steady in 2009 before accelerating early this year. It very well may be that the PRC now accounts for half the world’s coal use.

This is the other facet of Chinese coal policy and is just as disturbing. “It may very well be” that China accounts for half the world’s coal use because there is no longer an easy way to know. China stopped publishing coal production figures in March, possibly because it was about to cross the threshold of half of global consumption and certainly because the coal figures are embarrassing on a number of dimensions.

The PRC has been at odds with the U.S. and other countries about monitoring and enforcement of any international environmental treaty. But how could anyone trust China to monitor itself when it is no longer even willing to provide the most basic and critical piece of information?

The answer is that no sane person could. Cancun will be as useless as Copenhagen was, and for the same principal reason: Chinese coal. This time, however, no one will be surprised.