Feeds

Global warming much less serious than thought - new science

We're looking at just a couple of degrees with double CO2

Build a business case: developing custom apps

Climate scientists funded by the US government have announced new research in which they have established that the various doomsday global warming scenarios are in fact extremely unlikely to occur, and that the scenarios considered likeliest - and used for planning by the world's governments - are overly pessimistic.

The new study improves upon previous results by including data from the remote past, rather than only examining records from recent times.

"Many previous climate sensitivity studies have looked at the past only from 1850 through today, and not fully integrated paleoclimate date, especially on a global scale," says Andreas Schmittner, professor at the College of Earth, Ocean, and Atmospheric Sciences at Oregon State uni.

"When you reconstruct sea and land surface temperatures from the peak of the last Ice Age 21,000 years ago – which is referred to as the Last Glacial Maximum – and compare it with climate model simulations of that period, you get a much different picture.

"If these paleoclimatic constraints apply to the future, as predicted by our model, the results imply less probability of extreme climatic change than previously thought," Schmittner adds.

The baseline assumption of climate science at the moment is that given a doubling of atmospheric CO2 compared to pre-industrial levels the most probable result is that the Earth would see a surface temperature rise average of 3°C - and that there would be a significant chance of much bigger, perhaps fatal rises.

Schmittner and his colleagues' analysis says that the planet's climate simply can't be this sensitive to CO2 changes, however, or much more extreme events should have occurred at certain points in the past - and they did not. For instance, if the climate were sensitive enough that doubled CO2 could mean catastrophic warming, the low carbon levels seen 21,000 years ago should have resulted in an equally lifeless iceball planet.

"Clearly, that didn't happen," Schmittner says. "Though the Earth then was covered by much more ice and snow than it is today, the ice sheets didn't extend beyond latitudes of about 40 degrees, and the tropics and subtropics were largely ice-free – except at high altitudes. These high-sensitivity models overestimate cooling."

According to the new improved analysis, the most probable result as and when double CO2 occurs is actually a rise of just 2.3°C - only just above the 2°C limit which international climate efforts are seeking to stay within. Plainly there's no great need to fear a rise above 450 parts per million (ppm) CO2, as people currently do - in fact there's no likely prospect of getting near a 2°C temperature rise for a century or more at present rates of CO2 increase (rising about about 2 ppm/year at the moment from a level of 390-odd). And Schmittner and his colleagues' results show a much tighter grouping of possible futures, too, so the scope for way-out doomsday scenarios is hugely reduced.

The Australian quotes Schmittner as saying: "Now these very large changes (predicted for the coming decades) can be ruled out, and we have some room to breathe and time to figure out solutions to the problem."

The new study is published in top-ranking boffinry journal Science. The research was funded by the US National Science Foundation. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Boffins attempt to prove the UNIVERSE IS JUST A HOLOGRAM
Is this the real life? Is this just fantasy?
Our LOHAN spaceplane ballocket Kickstarter climbs through £8000
Through 25 per cent but more is needed: Get your UNIQUE rewards!
China building SUPERSONIC SUBMARINE that travels in a BUBBLE
Shanghai to San Fran in two hours would be a trick, though
LOHAN tunes into ultra long range radio
And verily, Vultures shall speak status unto distant receivers
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
Galileo, Galileo! Galileo, Galileo! Galileo fit to go. Magnifico
I'm just a poor boy, nobody loves me. But at least I can find my way with ESA GPS by 2017
EOS, Lockheed to track space junk from Oz
WA facility gets laser-eyes out of the fog
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Backing up distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.