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Re: OT: 1700 private jets "This REport"
Author: Edward
Date: 01-23-2015 - 23:04
Didn't read the article did you. This is about a newer study using 73 different methods of tracking temperature. The data just keeps coming.
Here is an extract:
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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.
Thermometre measurements only exist back to around 1860, so when climatologists reconstruct historical temperatures, they must use proxies. Tree rings, for instance, are useful because they are thicker during warm years when trees can grow faster.
Shaun Marcott of Oregon State University in Corvallis and colleagues have compiled 73 such proxies from around the world, all of which reach back to the end of the last glacial period, 11,300 years ago. During this period, known as the Holocene, the climate has been relatively warm – and civilisation has flourished.
"Most global temperature reconstructions have only spanned the past 2000 years," says Marcott.
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.
Here is an extract:
-----
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.
Thermometre measurements only exist back to around 1860, so when climatologists reconstruct historical temperatures, they must use proxies. Tree rings, for instance, are useful because they are thicker during warm years when trees can grow faster.
Shaun Marcott of Oregon State University in Corvallis and colleagues have compiled 73 such proxies from around the world, all of which reach back to the end of the last glacial period, 11,300 years ago. During this period, known as the Holocene, the climate has been relatively warm – and civilisation has flourished.
"Most global temperature reconstructions have only spanned the past 2000 years," says Marcott.
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.
