Scientists look beyond alarming milestone in carbon dioxide levels

May 08, 2014 by Alvin Powell
“We’re way out of the natural range. If there’s a symbol of us being at a dangerous level, it’s that we’re already at 400 parts per million,” said Ralph Keeling (photo 1), the son of the late Charles Keeling, whose “Keeling curve” alerted the world to rising carbon dioxide levels in the 1960s. Keeling was joined by Daniel Schrag (photo 2), director of the Harvard University Center for the Environment, for an event titled “Brave New World! Entering an Age of Climate Change Beyond 400 PPM.” Credit: Melanie Rieders

The world made a down payment on decades of dangerous weather last month, reaching an average atmospheric carbon dioxide level above 400 parts per million.

"No human being—ever—has witnessed this atmosphere, so breathe in deeply," Daniel Schrag, the Sturgis Hooper Professor of Geology and the director of the Harvard University Center for the Environment, said Monday during an event at the Geological Lecture Hall.

Though daily did top 400 parts per million at times last year, April marked the first time the monthly average topped that mark, reaching 401.33 ppm, according to Ralph Keeling, a Scripps Institution of Oceanography geochemist and son of the late Charles Keeling, whose "Keeling curve" alerted the world to rising carbon dioxide levels in the 1960s.

At one point during the conversation, Keeling was asked how to persuade climate change skeptics and create greater momentum for action. He called for a stronger emphasis on outreach and building trust.

"Just shouting louder doesn't do it, they've already tuned us out. You don't build trust by shouting louder."

The event, titled "Brave New World! Entering an Age of Climate Change Beyond 400 PPM," was sponsored by the Harvard University Center for the Environment and included a video address from former Vice President Al Gore. It came a day before a major report from the National Climate Assessment warned that climate change is already being felt across the United States—dry regions are growing drier, torrential rainstorms are increasing, heat waves and wildfires are becoming more severe, and forests are under attack from invasive pests accustomed to warmer temperatures.

Four hundred ppm is not a functional climate threshold that will suddenly trigger more dire consequences, Keeling and Schrag noted. It is, however, an indication that our best chance to avoid climate change has passed. Carbon dioxide concentrations are now nearly 50 percent higher than preindustrial levels, thought to have been 270 to 280 parts per million. A system as huge and complex as the planet's atmosphere changes slowly; even a dramatic response tomorrow—cutting emissions to zero—would likely be too late to halt dramatic effects.

"We're way out of the natural range," Keeling said. "If there's a symbol of us being at a dangerous level, it's that we're already at 400 parts per million."

Though Gore expressed optimism that significant action to address the problem was possible—citing changing public attitudes and declines in prices for renewable energy supplies—Keeling didn't share that feeling.

With fossil fuel burning largely unabated today, there's little chance of stabilizing within a few decades at 450 ppm, he said. Five hundred ppm, nearly double pre-industrial levels, is a more likely target, Keeling said—one that would be preferable to accelerated burning with no controls. He estimated that the Earth has enough fossil fuel reserves for atmospheric carbon dioxide to approach 2000 ppm, a level that would undoubtedly have devastating consequences and take thousands of years to lower significantly.

Halting carbon dioxide rise wouldn't take a complete cessation of burning fossil fuels, Keeling said. Scientists have known for some time that the increase has been slower than expected from the levels of fossil fuel burning. This is because the ocean and land act as carbon "sinks," absorbing significant amounts of carbon dioxide—roughly 43 percent of our emissions, meaning fossil fuels would have to be reduced by 57 percent to stop the accumulation of in the atmosphere. (Though ideally the actual reduction would be a bit more, Keeling said, to compensate for an expected slow decline in absorption by natural carbon sinks.)

International organizations seeking to address have called for an effort to minimize warming to an average of 2 degrees centigrade. That target is probably too high to avert dangerous change, Keeling said, and also low enough that there's probably no way to avoid it.

"If we're worried about dangerous climate interference, I think what we have to accept now is that we're already there," Keeling said. "We shouldn't be talking about avoiding dangerous climate interference, we should be accepting that something like 400 ppm is already a threshold. There's a loss of innocence that we've already bought into this problem deeply enough that the conversation has to change to being what do we do next."

Explore further: UN: CO2 pollution levels at annual record high

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TegiriNenashi
1.3 / 5 (15) May 08, 2014
"...dry regions are growing drier, torrential rainstorms are increasing, heat waves and wildfires are becoming more severe, and forests are under attack from invasive pests accustomed to warmer temperatures..."

...and global warming zealots becoming increasingly more desperate while clutching at straws and fabricating more lies.

supamark23
4.7 / 5 (14) May 08, 2014
"...dry regions are growing drier, torrential rainstorms are increasing, heat waves and wildfires are becoming more severe, and forests are under attack from invasive pests accustomed to warmer temperatures..."

...and global warming zealots becoming increasingly more desperate while clutching at straws and fabricating more lies.



[Citation needed]
Caliban
5 / 5 (13) May 08, 2014
"...dry regions are growing drier, torrential rainstorms are increasing, heat waves and wildfires are becoming more severe, and forests are under attack from invasive pests accustomed to warmer temperatures..."

...and global warming zealots becoming increasingly more desperate while clutching at straws and fabricating more lies.



Pearls of Denial from St. TugNads the Delusional.

ryggesogn2
1 / 5 (9) May 08, 2014
" I am a friend of climate forecasts. But the review of model results is important in order to ensure their credibility. It is frustrating that climate science is not able to validate their simulations correctly. The warming of the Earth has been much weaker since the end of the 20th century compared to what climate models show.""
http://www.breitb...onsensus
Caliban
5 / 5 (8) May 08, 2014
" I am a friend of climate forecasts. But the review of model results is important in order to ensure their credibility. It is frustrating that climate science is not able to validate their simulations correctly. The warming of the Earth has been much weaker since the end of the 20th century compared to what climate models show.""
http://www.breitb...onsensus


More Fool's Gold from the Vault of Irrelevant Inanity.

Moron.
animah
4.4 / 5 (7) May 08, 2014
Honest question to climate skeptics: Whats' the argument here? That while we know we will extract all known oil reserves and that will get us to a 7x increase of 2000ppm, it will have no effect?
TegiriNenashi
1 / 5 (10) May 08, 2014
...we will extract all known oil reserves and that will get us to a 7x increase of 2000ppm, it will have no effect?


Take a look at CO2 concentration graph. It took 50 years to increase concentration by measly 80ppm. The most pessimistic scenario on your site of worship
http://www.skepti...hp?r=332
is reaching 1000 ppm in next 100 years. The alarmists complete lack of vision and insistence that civilization would stop it's progress and would use the same technology that far in the future is ridiculous.

Bob Osaka
4.7 / 5 (7) May 08, 2014
Anyone for replacing the internal combustion engine? Automobiles are by far the largest single man-made contributor to carbon dioxide levels. The cost of maintaining the existing US interstate highway system, crumbling roads and bridges, is estimated at $1-2 trillion. The total cost thus far has been $425 billion. It would be cheaper, more energy efficient, much more environmentally friendly to completely revamp the system with linear motors. Many countries around the world have working high speed rail systems using linear motors, or mag/lev, magnetic induction transportation. In The US we would need to upscale the distances and downscale the vehicle for individual users.
Sometimes our actions or inactions,whether you believe it or not, become a threat to our collective survival. This may be one of those times.
animah
5 / 5 (6) May 09, 2014
would use the same technology

OK - so if I understand your response correctly, your position is that we are bound to move away from fossil fuels in the future, thus solving the problem.

So basically you support alternative energy. Isn't that the same as everyone else in the first place?
rwinners
5 / 5 (5) May 09, 2014
animah
5 / 5 (5) May 09, 2014
http://phys.org/n...l#inlRlv


Hmmm that's the more convincing argument I think. At historical lows (185ppm in the Pleistocene) we were in a glaciation. At historical highs (7,000 ppm in the Cambrian) all the glaciers of the Earth melted.

Would be nice to be wrong though.
ryggesogn2
1 / 5 (8) May 09, 2014
" I am a friend of climate forecasts. But the review of model results is important in order to ensure their credibility. It is frustrating that climate science is not able to validate their simulations correctly. The warming of the Earth has been much weaker since the end of the 20th century compared to what climate models show.""
http://www.breitb...onsensus


More Fool's Gold from the Vault of Irrelevant Inanity.

Moron.

AGWites would burn heretics at the stake, if they could and didn't release CO2.
runrig
5 / 5 (8) May 09, 2014
...we will extract all known oil reserves and that will get us to a 7x increase of 2000ppm, it will have no effect?


Take a look at CO2 concentration graph. It took 50 years to increase concentration by measly 80ppm. The most pessimistic scenario on your site of worship
http://www.skepti...hp?r=332
is reaching 1000 ppm in next 100 years. The alarmists complete lack of vision and insistence that civilization would stop it's progress and would use the same technology that far in the future is ridiculous.


Lets turn those numbers into percentage increases shall we?
Before the start of the industrial revolution CO2 levels stood at ~270ppm, and now they are 400ppm.
That is a 48% increase in the atmospheric gas most responsible for the Earth being at an ave of 15C as opposed to MS18C.
Try thinking of the feed-backs will you, and the fact that the Arctic will warm far quicker.
All present indications are that likely scenarios are on the optimistic side.
Captain Stumpy
5 / 5 (5) May 09, 2014
That is a 48% increase in the atmospheric gas most responsible for the Earth being at an ave of 15C as opposed to MS18C.
Try thinking of the feed-backs will you, and the fact that the Arctic will warm far quicker.
All present indications are that likely scenarios are on the optimistic side.
@runrig
here is a pretty decent video... its long but pretty good. Dr. Tyson brings up some carbon issues as well as some past/present issues. at least, I found it interesting. Have you seen it?

http://www.cosmos...43555624
cantdrive85
1 / 5 (7) May 10, 2014
When real science is introduced, well it can be said it makes a lot of people look foolish.

https://www.youtu...5koi7vaA
runrig
5 / 5 (7) May 10, 2014
When real science is introduced, well it can be said it makes a lot of people look foolish.
https://www.youtu...5koi7vaA

Sir, the author of the astounding Nobel winning revelations is........

"Dr. Pierre Latour is a Chemical Engineer, Vice-Chairman, Principia-Scientific International and consultant for identifying, capturing and sustaining measurable benefits from process control,........... Justified and installed advanced process control on most oil refinery and petrochemical processes ....Greenhouse Gas Theory skeptic: CO2 induced global warming and climate change. In addition, Dr. Latour is an engineer at Shell Oil and DuPont..."

This a post by a certain A Watts, on his Blog WUWT backing a certain R Spencer refuting the science free bollocks espoused in the above's video...
http://wattsupwit...incipia/

I hesitate to publicise it ... but there degrees of denialism and this is truly away with the fairies.
runrig
5 / 5 (4) May 10, 2014
That is a 48% increase in the atmospheric gas most responsible for the Earth being at an ave of 15C as opposed to MS18C.
Try thinking of the feed-backs will you, and the fact that the Arctic will warm far quicker.
All present indications are that likely scenarios are on the optimistic side.
@runrig
here is a pretty decent video... its long but pretty good. Dr. Tyson brings up some carbon issues as well as some past/present issues. at least, I found it interesting. Have you seen it?

http://www.cosmos...43555624

Capt:
Unfortunately I cant view it here - it's "geographically restricted".
TheGhostofOtto1923
3 / 5 (2) May 10, 2014
Here's something interesting

"Tom Darden's research team in the field of power generation reaction of nickel has many years of experience, both sides in respect of technical co-operation in the Chinese market applications in full compliance with China's industry-oriented and advantages, can unleash America's most sophisticated technological advantage, hoping the two sides ordered the pace of cooperation and achieve mutual benefit and win-win. Tom Darden as nickel-generation reactor technology representatives, will be free to put this technology transfer from the U.S. to China."

-Darden is the CEO of the company that bought Rossi out.

Nay you say? You better hope its real. It's the only possible replacement for fossil fuels besides nuclear, WORLDWIDE, for the near-term. Good thing china is interested.

We await the results of rossis long-term validation tests.
cantdrive85
1 / 5 (5) May 10, 2014
When real science is introduced, well it can be said it makes a lot of people look foolish.
https://www.youtu...5koi7vaA


Sir, the author of the astounding Nobel winning revelations is........

"Dr. Pierre Latour is a Chemical Engineer, Vice-Chairman, Principia-Scientific International and consultant for identifying, capturing and sustaining measurable benefits from process control,........... Justified and installed advanced process control on most oil refinery and petrochemical processes ....Greenhouse Gas Theory skeptic: CO2 induced global warming and climate change. In addition, Dr. Latour is an engineer at Shell Oil and DuPont..."

This a post by a certain A Watts, on his Blog WUWT backing a certain R Spencer refuting the science free bollocks espoused in the above's video...
http://wattsupwit...incipia/

I hesitate to publicise it ... but there degrees of denialism and this is truly away with the fairies.

Conspiracy!
Shootist
1 / 5 (5) May 12, 2014
"Generally speaking, I'm much more of a conformist, but it happens I have strong views about climate because I think the majority is badly wrong, and you have to make sure if the majority is saying something that they're not talking nonsense." - Freeman Dyson

"What I'm convinced of is that we don't understand climate." - Freeman Dyson

As a general rule, if Freeman Dyson doesn't understand something, you don't, either.
Caliban
5 / 5 (1) May 20, 2014
"Generally speaking, I'm much more of a conformist, but it happens I have strong views about climate because I think the majority is badly wrong, and you have to make sure if the majority is saying something that they're not talking nonsense." - Freeman Dyson

"What I'm convinced of is that we don't understand climate." - Freeman Dyson

As a general rule, if Freeman Dyson doesn't understand something, you don't, either.


Good thing we've got all those other thousands of lifetime science researchers, then --huh, shooty?

Sounds like -Dyson, Freeman Dyson and you may be a little too thick for the job.