The Price of Change - This just out from Dr James Hansen

The Price of Change
James E Hansen

"Sea level rise is one problem.  Carbon dioxide amounts of 400ppm (parts per million), expected in 2016 with current emissions, will cause an eventual sea level rise of about 25 metres.  China's land area will shrink rapidly, requiring about 250 million people to move inland.

"How rapidly ice sheets will collapse is uncertain.  A sea level rise of one metre every 20 years has occurred in the past ice sheet disintegrations.  But the human-made climate forcing is far greater and faster than past natural forcings. Ice shelves - tongues of ice protruding into the ocean and buttressing the great Antarctic and Greenland ice sheets - are melting.  Both ice sheets are now loosing over 100 cubic kilometres of ice each [year]. If mass loss continues to accellerate, ice sheet collapse may begin within decades."

"Governments must recognise this harsh fact:  Burning all fossil fuels would increase carbon dioxide to more than 555ppm and create a different planet - a desolate, ice-free planet with sea levels 75 metres higher than today.


As Glaciers Melt, Science Seeks Data on Rising Seas - N.Y. Times

Some quotes from this recent article in the NYT:

"As a result of recent calculations that take the changes into account, many scientists now say that sea level is likely to rise perhaps three feet by 2100 — an increase that, should it come to pass, would pose a threat to coastal regions the world over.
"And the calculations suggest that the rise could conceivably exceed six feet, which would put thousands of square miles of the American coastline under water and would probably displace tens of millions of people in Asia.

"Water that originated far to the south, in warmer parts of the Atlantic Ocean, is flushing into Greenland’s fjords at a brisk pace. Scientists suspect that as it melts the ice from beneath, the warm water is loosening the connection of the glaciers to the ground and to nearby rock.

"Moreover, scientists point out that if their projections prove accurate, the sea will not stop rising in 2100. By that point, the ice sheets could be undergoing extensive melting.
“Beyond a hundred years out, it starts to look really challenging,” said Richard B. Alley, a climate scientist at Pennsylvania State University. “You start thinking about every coastal city on the planet hiding behind a wall, with storms coming.”

"Climate scientists note that while the science of studying ice may be progressing slowly, the world’s emissions of heat-trapping gases are not. They worry that the way things are going, extensive melting of land ice may become inevitable before political leaders find a way to limit the gases, and before scientists even realize such a point of no return has been passed.
“The past clearly shows that sea-level rise is getting faster and faster the warmer it gets,” Dr. Rahmstorf said. “Why should that process stop? If it gets warmer, ice will melt faster.”

" ...sea-level rise is getting faster and faster the warmer it gets..."   Thanks Dr Rahmstorf!

Temperature is proportional to CO2 levels. (You know that!)
The monthly average CO2 levels trend for the year to date (Jan to October 2010) are:

387.38, 387.76, 387.86, 387.87, 387.94, 388.18, 388.45, 388.74, 389.21 ppm.
Every month upwards.  Every month the global temperature is higher, and 
"sea level rise is getting faster and faster".  Isn't it.
“Why should that process stop?" asks Dr Rahmstorf!
Yes, why indeed!