Beijing's big freeze on climate debate
If a single word could encapsulate our Zeitgeist, it would be 'climate'. It is, perhaps, in this spirit that officialdom in Beijing is caught up in an obscure academic debate about rainfall levels during the last years of the Tang dynasty.
Somehow during the 9th century, two great civilisations at opposite ends of the world collapsed - the Tang and the Maya in Central America. In a high-profile paper published early last year, a team of German scientists, led by geologist Gerald Haug of the National Research Centre for Geosciences in Potsdam, concluded climate changes were to blame in both cases.
This apparently touched a nerve in Beijing, which promptly despatched a team of top climate scientists to disprove Dr Haug's theory. Few people other than geoscientists would find the levels of titanium in lake sediment - or the presence of the isotopes of strontium and neodymium - terribly fascinating, but this was what the academic debate ultimately turned on. The larger political question, however, is why senior people in Beijing were so sensitive about an esoteric climate theory of dynastic collapse, particularly at this time.
National Metrological Centre chief scientist Zhang Deer told this newspaper that she was ordered by officials to drop everything she was doing to build a case against the German findings. She and her team eventually managed to write up a convincing rebuttal, which was published in a November issue of Nature, a premier international scientific journal. But since the South China Morning Post published her account of official pressure, our reporter said he had been having problems convincing mainland climate scientists to talk. Anything to do with climate, it seems, is politically sensitive on the mainland nowadays.
It should be noted that there was not a hint of anti-Chinese sentiment in Dr Haug's research. Linking climate and environmental changes to societal collapse has become a fashionable scientific sub-field. The best known offering to the general public so far may be the best-seller Collapse: How Societies Choose to Fail or Succeed, by US geography professor Jared Diamond.
Dr Haug's team has argued that severe winter monsoons and summer droughts contributed to crop failures and water shortages, which in turn led to social breakdowns in China. But the Chinese team said historical records showed the last years of the Tang period actually had unusually high summer rainfall and that the Germans misinterpreted data from lake sediment.
Party officials have been satisfied with Dr Zhang's hatchet job. They are more comfortable, apparently, with the traditional explanation of the fall of the Tang dynasty, which was usually attributed to corruption in the royal court, a weakened government and rising discontent across the country. One might think that these have uncomfortable parallels to contemporary problems plaguing the central government, such as endemic corruption within the party ranks.
But Beijing now has more pressing concerns with the environment. It is busy preparing a coming-out party to showcase its new powers to the world with the Olympics. It is trying to clean up the air in the capital in time for the Games. At the same time, it has stepped up a crackdown against environmentalists and unauthorised green groups.
Environmental degradation is now threatening the very economic juggernaut that has lifted tens of millions of people out of extreme poverty and brought legitimacy to the central government and its one-party rule. Last year, China surpassed the US as the world's leading emitter of greenhouse gases. Beijing clearly recognises the monumental problems of pollution and climate change. But it wants to carefully manage any remedial programme and orchestrate public discussion. It will not accept outside interference, including from unauthorised domestic non-governmental organisations. This is why officials are so sensitive about arcane theories of the Tang dynasty collapse.
Alex Lo is a senior writer at the Post