Climate outlook may be worse than feared, global study suggests

December 9, 2015, University of Edinburgh
A composite image of the Western hemisphere of the Earth. Credit: NASA

As world leaders hold climate talks in Paris, research shows that land surface temperatures may rise by an average of almost 8C by 2100, if significant efforts are not made to counteract climate change.

Such a rise would have a devastating impact on life on Earth. It would place billions of people at risk from , flooding, regional drought, and .

The study calculated the likely effect of increasing atmospheric levels of greenhouse gases above pre-industrialisation amounts. It finds that if emissions continue to grow at current rates, with no significant action taken by society, then by 2100 global land temperatures will have increased by 7.9C, compared with 1750.

This finding lies at the very uppermost range of temperature rise as calculated by the Intergovernmental Panel on Climate Change. It also breaches the United Nations' safe limit of 2C, beyond which the UN says dangerous climate change can be expected.

Research at the University of Edinburgh first created a simple algorithm to determine the key factors shaping climate change and then estimated their likely impact on the world's land and . The method is more direct and straightforward than that used by the IPCC, which uses sophisticated, but more opaque, computer models.

The study was based on historical temperatures and emissions data. It accounted for atmospheric pollution effects that have been cooling Earth by reflecting sunlight into space, and for the slow response time of the ocean.

A composite image of the Western hemisphere of the Earth. Credit: NASA

Its findings, published in Earth and Environmental Transactions of the Royal Society of Edinburgh, may also help resolve debate over temporary slow-downs in .

Professor Roy Thompson, of the University of Edinburgh's School of GeoSciences, who carried out the study, said: "Estimates vary over the impacts of . But what is now clear is that society needs to take firm, speedy action to minimise climate damage."

Explore further: Global warming: What if we do nothing?

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1.9 / 5 (9) Dec 09, 2015
These modelers apparently believe there is no cost to creating fear based upon uncertain models which base upon an incomplete understanding of the physical processes. I think they will be surprised by the blowback in the years to come.
1.9 / 5 (9) Dec 09, 2015
LOL...running simulations is now called "studies"
4.3 / 5 (6) Dec 09, 2015
"Such a rise would have a devastating impact on life on Earth. It would place billions of people at risk from extreme temperatures, flooding, regional drought, and food shortages."

Ah, no. That's 2 degrees. 8 is well above the human extinction level. At this point, whether it's 4 or 8 makes no difference. Once we're above human survival thresholds, we're above human survival thresholds. Being well above them makes little difference.
1.6 / 5 (7) Dec 09, 2015
I'm sick and tired of money being wasted on chicken little climate modeling that incorrectly predicts the future. It would be fine if the government wasn't taking the money from us by force to fund this. But both those in government and those getting the funding are invested in it, and find it profitable to steal from us for their own benefit, while claiming to be looking out for us.

It's disgraceful.
not rated yet Dec 09, 2015
Banker's wars will kill everyone long before climate has a chance
3.7 / 5 (3) Dec 09, 2015
I don't think we could reach 8C. Too many of us will be dead before we can get there.
3 / 5 (2) Dec 11, 2015
Unfortunately because of the amount of time CO2 stays in the atmosphere and the delay before it causes a warming effect, it is possible for us to pump enough into the air to cause 8 degrees before we die out somewhere between 4 and 7. In this scenario, the extreme predictions of complete societal collapse by 2050 would ironically be a good thing for the species (if not a good thing for all of us who would have to live through it).

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