Climate Change Could Be Faster, Bigger

Most climate change scientists believe that the earth must avoid raising its average temperature by about 2 degrees Celsius if we are to avoid the catastrophic effects of global warming. That target may be too high.

NASA’s James E. Hansen has an even grimmer warning:

The Earth’s average global surface temperature has already risen by 0.8 degrees Celsius since 1880, … and is now increasing by more than 0.1 degree Celsius every decade. At the current rate of fossil fuel burning, the concentration of carbon dioxide in the atmosphere will have doubled from pre-industrial times by the middle of this century, causing an eventual warming of several degrees.

If warming continues to that degree, sea levels could rise by as much as 6 meters from today’s levels.

Hansen also says,

We don’t have a substantial cushion between today’s climate and dangerous warming. Earth is poised to experience strong amplifying feedbacks in response to moderate additional global warming. Humans have overwhelmed the natural, slow changes that occur on geologic timescales.

Grim indeed.