The Paris School of Economics is hosting a really nice website on top incomes across 22 economies. The top incomes data stretches from the early twentieth century to the present day. For example, the share of total annual income going to the top 1% of earners in the UK has risen from 6% in the 1970s to close to 14% today. In other words, the income share of top earners in the UK is back to pre-WWII levels. A similar pattern exists for Ireland. You can access the database 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.