Is political union a prerequisite for a successful monetary union? Peter Rousseau tackles this question by looking at how monetary union arose in the United States. He argues that is was not until well after the Civil War that the US achieved a stable monetary union. In other words, it look a long time for the US to achieve monetary union. Maybe there is hope for the EU. However, the EU is not a political union in the same sense that the US was or is. You can read a review of the paper at NEP-HIS Blog and the full article is available here.
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.