Climate 'carbon budget' soon maxed out: study

February 23, 2016 by Marlowe Hood
There is less time to reduce carbon emissions and stop global warming than once thought, a new study shows
There is less time to reduce carbon emissions and stop global warming than once thought, a new study shows

The window of opportunity for humanity to cap global warming by slashing greenhouse gases is closing faster than previously thought, according to a study released Tuesday.

Earlier estimates of our "carbon budget"—the amount of heat-trapping carbon dioxide we can still put into the atmosphere without warming Earth by more than two degrees Celsius (3.6 degrees Fahrenheit)—have ranged from 590 billion to 2.4 trillion tonnes.

The new research says the upper limit is actually half that, some 1.24 trillion tonnes of CO2.

"We have figured out that this budget is at the low end of what studies indicated before," said lead author Joeri Rogelj, a climate scientist at the International Institute for Applied Systems Analysis in Austria.

"If we don't start reducing our emissions immediately, we will blow it in a few decades."

The goal of holding the rise in surface temperature to 2C—widely seen at the time as the threshold for dangerous warming—was first agreed by the world's nations in 2010.

But thousands of subsequent scientific studies have showed that even a smaller jump on the thermometer would have severe consequences, especially for poor nations.

With an increase so far of less than 1C (1.8F) over pre-Industrial Revolution levels, the world has already seen climate-boosted droughts, floods and megastorms.

The basics of climate change. 287 x 410 mm

Radical increase in ambition

As a result, the Paris Agreement adopted by the UN climate forum in December last year embraced a more ambitious target of "well below 2C," while pledging to strive for a 1.5C cap if possible.

CO2 emissions were about 40 billion tonnes in 2015, and are projected to continue climbing over the next decade, even taking into account the carbon-cutting pledges submitted by nearly 190 nations as part of the Paris Agreement.

If current emission rates are held steady, the 2C carbon budget would be spent in about 15 to 30 years, according to the new calculations.

For a 1.5C target, the carbon budget "would be exhausted in about one decade," Rogelj told AFP.

A delegate walks past a huge paper made thermometer ontop of a globe set up by Greenpeace

"It is beyond doubt that ambition thus needs to be increased radically from anything we have experienced to stabilise warming at either 1.5C or 2C—or even higher temperature levels," he said by email.

Rogelj and half-a-dozen colleagues sought to understand why previous estimates of the carbon budget vary so widely.

Part of the gap stems from different methods and scenarios that project trends into the future.

Another factor is that many studies looked only at the dominant greenhouse gas CO2, using it as a proxy for all others, including methane and nitrous oxide.

Carbon dioxide accounts for more than 80 percent of .

"Neglecting the warming from other leads to larger carbon budgets," Rogelj explained.

Focusing only on CO2 helps scientists understand how the Earth system works, but is not very useful for real-world policy, he added.

"In our proposed range, we take into account warming by all human emissions, and thus shave of the top-end of studies that looked at CO2 only."

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29 comments

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Gimp
2 / 5 (4) Feb 23, 2016
oh my
antigoracle
1.6 / 5 (13) Feb 23, 2016
LOL. Those dickheads and their AGW agenda.
Maggnus
4.3 / 5 (11) Feb 23, 2016
Deny deny deny - dumb dumb dumb.
unrealone1
1.4 / 5 (10) Feb 23, 2016
No global warming for 18 years?
Maggnus
4.6 / 5 (9) Feb 23, 2016
No global warming for 18 years?


Bahahaha stupid, not just dumb! Do you not know how to read dumdum?
24volts
5 / 5 (3) Feb 24, 2016
People better learn to enjoy the heat then because there is no way in hell the worlds population
is going to be able to reduce it enough in that time without a major world effort and people simply won't cooperate to that extent. That is only one reason it isn't going to happen. There are quite a few more.
michael_frishberg
3 / 5 (2) Feb 24, 2016
LOL. Those dickheads and their AGW agenda.

agenda: No one alive in 100 years. vhemt.org
SteveS
4.5 / 5 (8) Feb 24, 2016
No global warming for 18 years?


But plenty of warming in the last 20 and 16 years.
http://www.woodfo...rom:1996
unrealone1
1 / 5 (4) Feb 24, 2016
SteveS
4.6 / 5 (9) Feb 24, 2016
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1995
I see cooling..


The hadcrut3 data on woodfortrees only goes up to 2014 so your first link is to data between 1995 and 2014 and shows clear warming, your second link cherry picks 16 years between 1998 to 2013, and your last link shows data between 1980 and 2014 which again shows very clear warming. None of them back up your "No global warming for 18 years" claim.

Try the GISTEMP surface temperature or UHA lower tropospheric temperature datasets, both of those are up to date on woodfortrees.

http://www.woodfo...97/trend
http://www.woodfo...98/trend
runrig
5 / 5 (8) Feb 24, 2016
I see cooling..

.
Taking a trend from such a spurious spike as that of the 97/98 Nino is cherry-picking in the extreme.
But let's run with it.

http://woodfortre...ss/trend

Is why that is bollocks.

The first 18 yrs trend (red) is just as valid as the last (obviously). Now extend that to the right, and also extend your *pause* trend (blue) to the right. Where do they meet??

For there to have been a *pause* the blue should have really been BELOW the (extended) red from the start BUT NO - it does cross it until ~2025.

SO your *pause* was actually a STEP-UP in temps and it's actually still WARMER than it would have been if the initial trend (red) had been maintained throughout.

There is no "step-up" just as there is no *pause* .

Because of the oversensitivety of RSS MSU/AMSU to atmos WV and the overall inexactitude of measuring a surface temp from a depth of the troposphere.
krundoloss
1 / 5 (6) Feb 24, 2016
What is the AGW agenda? Lie about global warming to sell more solar panels? Please enlighten me as to why nations would band together to propogate a false idea and cost themselves trillions of dollars?
HeloMenelo
4 / 5 (4) Feb 24, 2016
Big dumb bufoon antisciencegorilla having another bainfart,now... bring on your puppets, we're waiting...... :D
unrealone1
1 / 5 (7) Feb 24, 2016
No warming for 18 years please Google..
RSS satellite monthly global mean surface temperature shows no warming for 18 years
RSS satellite is not "adjusted" or near a heat island.
SteveS
5 / 5 (7) Feb 24, 2016
No warming for 18 years please Google..


Google isn't proof or evidence, show me the surface temperature data that supports your claim.

RSS satellite is not "adjusted"


RSS are now on version 3.2 of their data. Just because methodology changes does not make the data "adjusted", all changes in all the main datasets are justified by peer reviewed papers. Claiming that any dataset that doesn't support your position has been dishonestly "adjusted" is to descend into conspiracy theories that have no place on a science site.
gkam
3.7 / 5 (6) Feb 24, 2016
The scientists of the world are greatly concerned about the rising temperatures, but unrealone1 says it is not happening.

I guess that settles that, . . .
runrig
5 / 5 (7) Feb 24, 2016
No warming for 18 years please Google..


http://woodfortre...ss/trend

Is why that is bollocks.

The first 18 yrs trend (red) is just as valid as the last (obviously). Now extend that to the right, and also extend your *pause* trend (blue) to the right. Where do they meet??

For there to have been a *pause* the blue should have really been BELOW the (extended) red from the start BUT NO - it does cross it until ~2025.

SO your *pause* was actually a STEP-UP in temps and it's actually still WARMER than it would have been if the initial trend (red) had been maintained throughout.

There is no "step-up" just as there is no *pause* .

Because of the oversensitivety of RSS MSU/AMSU to atmos WV and the overall inexactitude of measuring a surface temp from a depth of the troposphere.

Read more at: http://phys.org/n...html#jCp
runrig
5 / 5 (6) Feb 24, 2016
No warming for 18 years please Google..
RSS satellite monthly global mean surface temperature shows no warming for 18 years
RSS satellite is not "adjusted" or near a heat island.

Idiot.
unrealone1
1 / 5 (7) Feb 24, 2016
SteveS
5 / 5 (6) Feb 24, 2016

http://jenniferma...herglen/


A blog is not evidence, and you may have to explain the relevance of your second link.

There really is no point discussing this with you further if all you have is a blind belief in conspiracy theories.
runrig
5 / 5 (4) Feb 25, 2016
unrealone1:

I'd suggest you (and the other usual suspects) watch the following.....

https://www.youtu...dYvz0VwQ
unrealone1
1 / 5 (5) Feb 25, 2016
The unhomogenized/raw mean annual minimum temperature trend for Rutherglen for the 100-year period from January 1913 through to December 2013 shows a slight cooling trend of 0.35 degree C per 100 years. After homogenization there is a warming trend of 1.73 degree C per 100 years. This warming trend is essentially achieved by progressively dropping down the temperatures from 1973 back through to 1913. For the year of 1913 the difference between the raw temperature and the ACORN-SAT temperature is a massive 1.8 degree C.
There is absolutely no justification for doing this.

http://jenniferma...herglen/
http://www.theaus...62ecc480
SteveS
5 / 5 (5) Feb 25, 2016
There is absolutely no justification for doing this.

http://jenniferma...herglen/


A blog is not evidence or even a reliable source of information
http://www.theaus...ac7b562a

Just for the record you seem to prefer RSS to UAH lower troposphere temperature data, is this because you suspect Drs Spencer and Christy of "adjusting" the data to show more warming?
runrig
5 / 5 (5) Feb 25, 2016
Unreal:
First - one climate station does NOT global warming make.
2nd: Here is BOM's explanation:

"The need for the adjustment made to Rutherglen data for the period prior to 1966 was determined from an objective statistical test that showed an artificial jump in the data during this period.
While it is not necessary to have supporting documentation to justify correcting a statistically determined artificial jump in the data, it is of interest that the change at Rutherglen is very likely associated with a change in the location of the weather station."

3rd: Read about it fully here ....

http://blog.hotwh...40239358

You need to consider these 3 questions...
Are climate scientists incompetent overall?
Are climate scientists involved in a conspiracy to hide the truth and are lying for whatever reason?
They know more than you?

The answer my friend is blindingly obvious.
unrealone1
1 / 5 (4) Feb 25, 2016
A study done by NOAA scientists in July contradicted previous evidence that global warming was declining. The House science committee now demands internal communications related to the study
http://www.csmoni...na-video
http://www.dailym...lW1uFeQO
Climategate scientists DID collude with government officials to hide research that didn't fit their apocalyptic global warming.
NASA climate scientists:
We said 2014 was the warmest year on record... but we're only 38% sure we were right.

http://dailycalle...ng-data/
300 Scientists Want NOAA To Stop Hiding Its Global Warming Data

SteveS
5 / 5 (4) Feb 25, 2016
unrealone1:

I'd suggest you (and the other usual suspects) watch the following.....

https://www.youtu...dYvz0VwQ


I've just re watched this, If I could give you another 5 stars I would.

@unrealone1

Watch it and ask yourself the three questions.
SteveS
5 / 5 (5) Feb 25, 2016
@unrealone1

Take a look at these
http://www.woodfo...rom:1995
http://www.woodfo...rom:1995
Do you think Drs Spencer and Christy "adjusted" the data to show more warming?
btw both graphs show warming over the last 16 17 19 and 20 years. The UAH data also shows warming over the last 18 years.
Captain Stumpy
4.3 / 5 (6) Feb 25, 2016
unrealone1:

I'd suggest you (and the other usual suspects) watch the following.....

https://www.youtu...dYvz0VwQ
@runrig
if i could give you 100 stars, i would
that single video pretty much debunks (and explains) almost all of the posters here who are posting anti-mainstream science rhetoric ... from antiG to zephir

I LOVE THOSE THREE QUESTIONS!
i am posting them!

.

EITHER:
1- research scientists are all incompetent

2- research scientists are all in a conspiracy to deceive you

3- research scientists know something you don't

-potholer54

runrig
5 / 5 (6) Feb 25, 2016
A study done by NOAA scientists in July contradicted previous evidence that global warming was declining. The House science committee now demands internal communications related to the study
http://www.csmoni...na-video
300 Scientists Want NOAA To Stop Hiding Its Global Warming Data


Unreal:
If it makes you feel good - then OK, if you say so.....
And the right wingnut denier Blogs you get your "science" from.

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