I've just come from a fascinating QUCEH seminar by Ting Xu on the role of useful knowledge in explaining the Great Divergence between China and Europe which emerged c.1600. China, of course, has come a long way in the past 30 years. However, a recent NBER working paper, which will be the first chapter in the Oxford Companion to the Economics of China, suggests that China faces at least three challenges if it is to maintain its current growth trajectory. First, it has an overstretched natural resource base - air pollution and water scarcity are major problems in China going forward. Second, inequality between regions and within regions is high. Such inequality could create political instability and stunt economic growth. Third, state-owned enterprises, because of weak governance structures and subsidised inputs, are distorting the economy and will hamper its growth moving forward.
The Berkeley Earth Project , an independent study of global warming, has found that the earth has become a degree warmer over the past half century. However, the statistical uncertainty surrounding pre-1920 estimates makes it very hard to say much about long-term trends - click here for graph . This is one of my concerns with the global warming debate - we simply don't have trustworthy long-run data which looks at temperature changes over the last millennium (or two). My second concern with the global warming debate is that it is very hard to prove any sort of casual link between global warming and human activity. The scientists may be able to show correlation between global warming and our production of carbon dioxides etc., but correlation is not causation. My third concern with the debate is that those who are sceptical or agnostic are stereotyped as flat-earthers or intellectually-challenged crackpots. This only stifles debate and the progress of science itself.