'Safe' climate means 'no to coal'
Coal is one of the largest contributor to CO2 emissions along with fossil fuels.It took us 250 years to burn the first half trillion of it , and on current projections we'll burn the next half trillion in less than 40 years.About three-quarters of the world's fossil fuel reserves must be left unused if society is to avoid dangerous climate change, scientists warn.More than 100 nations support the goal of keeping temperature rise below 2C. But the scientists say that without major curbs on fossil fuel use, 2C will probably be reached by 2050. Writing in Nature, they say politicians should focus on limiting humanity's total output of CO2 rather than setting a "safe" level for annual emissions. "To avoid dangerous climate change, we will have to limit the total amount of carbon we inject into the atmosphere, not just the emission rate in any given year,"The UN climate convention, agreed at the 1992 Rio Earth Summit, commits countries to avoiding "dangerous" climate change, without defining what that is.Last week saw the publication of data showing that industrialised countries' collective emissions rose by about 1% during 2007.