Business Green: Despite global recession, falling carbon prices and ongoing questions about the effectiveness of carbon trading, credits equivalent to 82bn tonnes of carbon dioxide were traded last year, an increase of 68 per cent. According to research released yesterday by analyst firm Point Carbon, the falling price of carbon meant that the value of the global carbon market rose only marginally from EUR92bn (£82bn) in 2008 to EUR94bn (£84bn) in 2009. However, the market still continued to …