It’s official. A NASA report indicates that 2010 has tied 2005 as the hottest year since reliable global climate records began in 1880. And, before anyone can bring out the tired objection that one hot year does not constitute a warming trend, the 12 hottest years on record have all occurred within the last 13 years.
Since the warming trend became apparent in the 1970s, average global temperatures have been increasing by about 0.2C per decade. Temperatures have now increased by about 0.8C from the pre-industrial average. It is generally accepted that with the carbon we have currently emitted, even if all emissions ceased today, temperatures would continue to rise another 0.6C, for a total warming so far of 1.4C. It is also generally accepted that if we wish to avoid a climate catastrophe with potential consequences up to and including global mass extinction, warming must be kept to a maximum of 2.0C. That means that we have at most 3 decades left to reduce emissions to a sustainable level (about 1/5 of current emissions).
Personal Climate Change 