Earth's temperature is changing faster now than at any time since the last ice age, according to a new analysis of global temperatures spanning the last 11,300 years....
The study has produced the first extension of the notorious "hockey stick" temperature graph all the way back to the end of the last ice age.
It suggests that we are not quite out of the natural range of temperature variation yet, but will be by the end of the century.
Marcott's graph shows temperatures rising slowly after the ice age, until they peaked 9500 years ago. The total rise over that period was about 0.6 °C. They then held steady until around 5500 years ago, when they began slowly falling again until around 1850. The drop was 0.7 °C, roughly reversing the previous rise....
Then, in the late 19th century, the graph shows temperatures shooting up, driven by humanity's greenhouse gas emissions.
Over the Holocene, temperatures rose and fell less than 1 °C, and they did so over thousands of years, says Marcott. "It took 8000 years to go from warm to cold." Agriculture, communal life and forms of government all arose during this relatively stable period, he adds. Then in 100 years, global temperatures suddenly shot up again to very close to the previous maximum.Here's the updated graph from http://www.newscientist.com/data/images/ns/cms/dn23247/dn23247-1_300.jpg
How fast temperatures change is the real issue of climate change, says Mann. "That's what challenges our adaptive capacity." Rapid change means farming practices must alter quickly, and preparations for extreme weather events must also be rapidly put in place.
Edit: The Atlantic reports on the same study: We're Screwed: 11,000 Years' Worth of Climate Data Prove It with a similar graph:
As does Scientific American: Global Average Temperatures Are Close to 11,000-Year Peak
And the ABC: Earth on track to be hottest in human history: study
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