in 1990 to 1.6 billion tonnes in 2008. This exceeds the 0.7 billion tonne reduction that developed nations must make each year to meet their Kyoto targets, say the authors of a recent study published in US scientific journal Proceedings of National Academy of Sciences. 4 May topic 2012 - 2011 - 2010 - 2009 - 2008 - 2007 - 2006 - 2005