Thursday, July 30, 2015

Climate change: Halfway there

In 1992 the United Nations Framework Convention on Climate Change committed the world to preventing
"dangerous anthropogenic interference with the climate system". This is generally interpreted as limiting climate change to an increase of no more than 2 degrees Celsius over pre-industrial levels. The bad news? We're already halfway there.

IT’S the outcome the world wants to avoid, but we are already halfway there. All but one of the main trackers of global surface temperature are now passing more than 1 °C of warming relative to the second half of the 19th century, according to an exclusive analysis done for New Scientist.


Kevin Cowtan of the University of York, UK, created and still maintains one such record, called “Cowtan & Way version 2.0″. It is based on another record, maintained by the UK Met Office, called HadCRUT4. Cowtan’s version differs because it compensates for missing data from areas with few weather stations, like the Arctic.

The various records also show temperature changes relative to different baselines. For instance, NASA’s GISTEMP record shows warming relative to the 1951 to 1980 average.

At the request of New Scientist, Cowtan adjusted his and other measures to show annual warming relative to the same time frame: the 1850 to 1899 period. All but one set of adjusted figures show that we will have already passed 1 °C before the next round of UN talks on a global climate treaty get under way in December (see graph).

“It looks very likely that all except HadCRUT4 will break 1 °C this year,” says Cowtan. “HadCRUT4 is somewhat dependent on a strong El NiƱo boost.”

And with global CO2 concentrations now over 400 parts per million, we're now pretty much committed to failure. Meanwhile, our government does nothing. Heckuva job our leaders are doing there. But I guess the incentive for action is low when you won't be alive to have to live with the consequences.