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New CO2 Milestone: 3 Months Above 400 PPM

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April fell first. It lasted through May. Now June will be the third month in a row with average carbon dioxide levels above 400 parts per million.

Atmospheric concentrations of the greenhouse gas, which helps drive global warming, haven’t been this high in somewhere between 800,000 and 15 million years.

Click image to enlarge.

And while the 400 ppm mark is somewhat symbolic (as the increase in warming between 399 ppm and 400 ppm is small), it serves to show how much carbon dioxide has been put into the atmosphere since preindustrial times, when concentrations were around 280 ppm. The increase in this and other greenhouse gases in the atmosphere has warmed Earth’s average temperature by 1.6°F since the beginning of the 20th century. World leaders agreed at a UN summit in 2009 to limit warming to 3.6°F, but prominent climate scientists like James Hansen have said that amount of warming will still be too much.

While other scientists differ on pinpointing particular numbers and limits, many who study climate change agree that some kind of action is needed.

“It is urgent that we find a way to transition to non-carbon fuels as our source of primary energy,” said Pieter Tans, a climate scientist with the National Oceanic and Atmospheric Administration.

The world first passed the 400 ppm milestone on May 9, 2013. The first 400 ppm measurement of 2014 came two months earlier. CO2 concentrations at the Mauna Loa observatory in Hawaii, which have been monitored since 1958, have been steadily above that level since the beginning of April, which marked the first full month with an average CO2 level above 400 ppm.

While concentrations of CO2 have begun their seasonal decline from their May peak (which was just shy of 402 ppm), the daily averages have stayed consistently above 400 ppm. With the month almost at an end, June’s average will be above 400 ppm.

Daily and weekly averages of carbon dioxide concentrations at the Mauna Loa Observatory for the first six months of 2014.
Click image to enlarge. Credit: Scripps Institution of Oceanography

That means it will be the first time in recorded history with this many weeks in a row of such high atmospheric concentrations of CO2.

"It still feels a bit surreal now to be reporting concentrations over 400 ppm,” Ralph Keeling, who runs the monitoring program at Mauna Loa, told Climate Central after the April milestone. “Even though it was pretty much inevitable that we would get to this point, it still takes some getting used to.” (Keeling’s father, Charles, began the monitoring effort, and the graph showing the rise of CO2 over time is known as the Keeling Curve.)

Given the typical rate of decrease in concentrations, which happens as vegetation in the Northern Hemisphere sucks up CO2, they may only dip consistently below 400 ppm come the third week of July, Tans said.

The levels of CO2 in the atmosphere vary not only through humanity’s addition of the gas through industrial processes, but also with the biological cycle. Concentrations begin their rise in the winter, when plants are dormant, and continue rising through spring. They reach their peak in May and then begin to decline because plants are in full bloom and are pulling CO2 from the atmosphere to fuel photosynthesis.

But plants only pull so much CO2 out of the atmosphere in a given growing season. Each year they leave a growing excess of about 2 ppm behind, which is why the 400 ppm mark came earlier this year than last and will come earlier still next year.

Tans expects the first 400 ppm measurement of 2015 to happen in February, and for concentrations to stay above that mark through July — a full six months. In just another year or so of CO2 building in the atmosphere, the world will be above 400 ppm year-round.

“As long as human society continues to emit CO2 from burning fossil fuels, CO2 in the atmosphere and oceans will continue to increase,” Tans said.

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Comments

By James Wrightsman (Bronxville, NY 10708)
on June 30th, 2014

We cannot surrender to global warming.  Even though mankind is a bit slow when it come to realizing danger, S/he is capable of being very innovative.  We will win.  It won’t be after a lot of disasters, but we will win.

Reply to this comment

By Robert Sweetman (Rogue River,OR)
on July 1st, 2014

It will require a global effort for humanity to demand a transition from fossil-fuels to a Manhattan project of developing quantum flux zero-point energy and for once in our lives put the moral relevance of saving humanity as being more important than profits by giving up the meter of energy.

Thats the only reason it was never fully developed as it is.

The fact is we are already in a runaway global warming scenario right now when you read between the lines of the IPCC Report of 2013 when they make reference to having to resort to geo-engineering application of heavy-metal aerosols to avert the worst-case scenarios of global runaway warming, when we have had an international effort to do that already for many years around the globe which oughta tell you the nature of the emergency as they have taken it upon themselves to risk the horrific damage to public health aerosol applications represent, notwithstanding the entire web of life and destruction of the ozone already taking place.

As it is they can alter pressure gradients around the globe with HAARP, have new ionizing technologies running behind it, and now we have ch 4 methane as the secondary feedback trigger being released now as the co2 already baked in has caused the most powerful greenhouse gas of all now showing up in spikes in the arctic.

Personally,...as long as they put money above life and maintaining the life-support of a fiat failed socio-economic system of empire to maintain it at any cost with burning fossil fuels, we will have baked so much CO2 and CH4 methane hydrates as the biggest trigger-mechanisms for runaway global warming already, making it a moot point on heading straight for a mass human extinction event where we have surpassed the narrow window of earths habitable zone for human life to exist, where no food and water becomes available

Former University of Arizona Professor Emeritus in Evolutionary Biology, Natural Resources and now Climate Science, Guy Mc Pherson has made a compelling case we have already surpassed runaway global-warming.

has written a summary update of where he believes we are right now, and provides links to the peer-reviewed science he uses to formulate his analysis for you to make your own analogy which provides direct access to information that most people have no clue on how to obtain, or analyse.

Particularity with climate change deniers who because they lack the scientific literacy to be rational and objective in interpreting science products, resort to arguing their case based on ideology, not facts.

Nature Bats Last: A Summary Update on Climate Change Science
ttp://guymcpherson.com/2013/01/c

Reply to this comment

By Craig Dillon (Chicago)
on July 1st, 2014

What do you mean by “winning”?
Homo Sapiens is the most adaptive species ever.
Will we adapt? Yes
Will we survive? Yes
Will we stop Global Warming and Climate Change? No.
The process is too far advanced. The methane and CO2 feedbacks have taken control.
It will take decades to take our energy off of fossil fuels.

Reply to this comment

By Snowball (Italy)
on July 4th, 2014

We’ll adapt, of course we will. But it will be a disaster for any other species in the world. We are not alone and this is not OUR WORLD!

Reply to this comment

By Snowball (Italy)
on July 6th, 2014

But we are not alone in this world and not everyone can adapte

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By Aaron
on June 30th, 2014

That chart was the part in ‘An inconvenient truth” when Mr. Gore had to get on that platform to elevate him way up to illustrate how abnormal the spike is. I have to agree with Hansen, I mean, if you consider how damaging 1.8 degrees has been, to double that as a goal is insane, but perhaps sadly realistic, but still not a good idea to promote that as the idea that we’re o.k. if we just stay slightly below that line, because that’s wrong because of the dynamics of positive feedback loops, which will take over irrespective of what our emmissions are at some point, if it hasn’t already happened.

Reply to this comment

By Stuart Blaber (Athens, Ontario K0E 1B0)
on June 30th, 2014

Fenner’s prediction of our total extinction by 2100 appears to right on schedule.  We are not so smart after all unless you think killing ourselves is really intelligent.

Reply to this comment

By Glenn Klotz (Margate City)
on July 1st, 2014

I don’t think we’re giving our species enough credit considering our 5 mil. yr. history. We made it through 6 Ice Ages with just Fur, Fire and Foraging and managed to get to 7 bil. people while at it. Its going to   be tough up ahead , but we will adapt. Do we really have any choice?

Reply to this comment

By Andy Koenigsberg (Westborough, MA 01581)
on July 10th, 2014

No, we don’t have a choice. The problem is that there will be a lot less of us as the climate progresses into to the new normal. As others have said, we are not the only species on the planet and it is already clear that most flora and fauna cannot swim, walk, crawl, fly, migrate to higher, lower, wetter, drier, cooler, warmer climates as fast as we can.

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By Bob Bingham (Kerikeri)
on June 30th, 2014

The last time the world had 400 ppm of CO2 was 3.5 million years ago and the seas were 7 metres higher and it was 3C warmer. The trees and plants at that time were adapted to the climate that went with it. Those trees had taken thousands or years to evolve to match those condition. The trees we have today are adapted to a CO2 level of 280 PPM and a climate 0.8C cooler and are rapidly going into conditions 2C warmer and with dramatical changed rainfall conditions of either drought or flood.
We can expect to see much large numbers of trees and other plant life dying in the coming years. http://www.climateoutcome.kiwi.nz/climate-threats.html

Reply to this comment

By Gee
on July 1st, 2014

One of the things you left out is the evolution of mammals, that were in their infancy 3 1/2 million years ago.  I have serious questions as to the flexibility of man, as our species seems to be developing a lot of intolerances lately.  Everyone has an allergy or they just aren’t cool.  Neurology is in its infancy and it can’t handle all the aches and pains that are being thrown at it.  We aren’t the cockroaches we like to think we are, and the people that are most at risk are the people that think they aren’t at risk.  Irony is like that.

Reply to this comment

By graycat
on July 19th, 2014

By Gee,    mammals have been around some fifty times longer than your 3-1/2 million years.  There’s evidence of mammal-like creatures predating the dinosaurs, and true mammals during Jurassic and Cretaceous dinosaur eras.

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By John Aldis (Las Vegas Nv 89103)
on June 30th, 2014

Won’t longer growing seasons offset increasing co2?

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By mel (Ithaca, NY 14850)
on July 1st, 2014

Not with dessertification happening all over the globe.

We need more trees and less cars.

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By Keith Davis (Jerome ID 83338)
on July 2nd, 2014

Well, yes…. But 3.5 million years ago there was 400 ppm and the planet was covered with trees. Not corn fields, wheat fields, soybean fields - trees.  So… how did we get from 400 ppm 3.5 million years ago to only 280 ppm at the start of the industrial revolution? It didn’t just happen. It happened because of - Trees. It took those trees a million years to suck 220 ppm out of the atmosphere.  So…. yes…. a longer global growing season would probably offset the CO2 that you and everyone in your neighborhood emit next year. But will there be a longer growing season? Ask the Sahara, which, at one time had a magnificent growing season.

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By Christopher Ryan Brown (San Francisco)
on July 4th, 2014

While you are correct that trees previously lowered the CO2 in our atmosphere, they were allowed to do so because they did not decay when they died.  The mutation that allowed trees to grow tall also made them indigestible to other organisms for a full million years, at which time the other critters finally developed the ability to eat them safely.  This meant that all the CO2 they absorbed in their lifetime stayed in their bodies undisturbed after death, and instead of decaying they fossilized and eventually became the fossil fuels that we know and love today.

This means two things.  First, modern trees decay after death and release all their absorbed CO2 into the atmosphere, meaning we can no longer expect them to absorb our emissions for us.  The only way we can get trees to absorb twice as much CO2 is by planting twice as many trees, and instead we are actually deforesting them.  So not gonna help.

Second, by burning up most of the fossil fuels on the planet we are effectively releasing nearly one million years’ worth of CO2 that had laid dormant in dead trees.  A huge amount of the CO2 that was absorbed from the atmosphere during that time, is now being directly released by the burning of fossil fuels.

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By Andy Koenigsberg (Westborough, MA 01581)
on July 10th, 2014

I think you have your geologic history a tad bit wrong.  Trees, in the modern sense of the term, have been around since the Mesozoic (over 100 million years ago) and decayed quite nicely well before 3.5 million years ago. Before their demise 65 million years ago, dinosaurs had no trouble munching on them.  During the Carboniferous, about 360 to 300 million years ago, conditions were such that a great deal of dead plantlife was buried and took its carbon with it to become coal (not oil).

Carbon is also sequestered in dead marine organisms and in fact, far more carbon is sequestered in the form of calcium carbonate than is absorbed by terrestrial plant life (see White Cliffs of Dover) and other massive limestone formations world wide. The problem now is that with acidification of the oceans, CaCO3 is more easily disolved and less likely to make it to the ocean bottom in the form of microorganism shells.

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By Ivan Steele
on July 2nd, 2014

No.  More heat does not mean longer growing seasons. Light—and temperature in the ranges that present species are adapted to (which varies by species and types) are what matter.  For many plants, when it gets to hot they stop growing (or even die. ) so the extension of warmth in terms of longer “warm” seasons also extends longer (and hotter) periods too hot for growth of the plants that are used to it. Light will not change from climate change, though cloud cover, unpredictably, could (more clouds reflect more sunlight, but also traps more heat, particularly at night when it is critical to cool off some), but day night time won’t change.

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By Mark from New England (Nashua NH 03064)
on July 2nd, 2014

No.

Reply to this comment

By Anetha Prater (salado, TX 76571)
on July 1st, 2014

Mother Earth will correct herself - whether mankind can live through the correction is another thing.  The correction can be tolerable or it can be catastrophic.  It’s up to us.

Reply to this comment

By bob (wa)
on July 1st, 2014

Eventually global warming will kill s significant amount of humans, thus lowering the co2 and stabilizing.

Reply to this comment

By T. Whitney (Dayton, OH)
on July 1st, 2014

After a fair amount of reading, I am convinced that scientists have no clue how an increase in the CO2 level will affect the feedback mechanisms - it may trap heat, melting the ice caps, and causing an extended interglacial warming period; or, the melting ice caps may decrease salinity, interrupting the ocean currents, pitching the balance into rapid cooling.  OR, an unforseen event - suddenly increased or decreased solar output - may pitch the balance either way.

The system is just too complicated, and we don’t have enough data to know.

The best thing we can do is prepare for climate change.  Even if we slow the rate of CO2 burping into the atmosphere - if it even makes a difference - there is no way we can control the the events that natural history has shown lead to multiple glacial periods in the past.

If we don’t prepare - which involves means of relocating millions of people and absorbing them into local communities - there WILL be significant death, resulting in stabilization of the environment.  The earth doesn’t care if we are here or not - it will continue on.  It’s just the nature of our existence.

Sorry to be so glum.

Reply to this comment

By rlp2451 (15541)
on July 1st, 2014

Does it not make anyone wonder that the observatory sits next to an active volcano that recently has shown signs of greater acivity?

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By David Ballard (San Rafael CA 94903)
on July 1st, 2014

How about requiring all new construction to get 50% of its predicted usage energy from solar power? Easy to install solar panels when building is being built, give tax rebate, creates jobs, etc. No solar panels no building permit.

More utopian/not-so-realistic idea require all buildings already standing to retrofit and get at least 25% of current power usage from solar.

Reply to this comment

By James Richard Tyrer (Green Valley, AZ, 85614)
on July 5th, 2014

It isn’t actually possible for buildings to “get” 50% of their energy use from solar panels without storage.  The typical grid tied installation is either drawing from or feeding into the grid on a minute to minute basis effectively using the gird as though it was a battery.  The problem is that the grid isn’t a battery and does not provide storage.  So, if too many people do this, the grid will become unstable.

Reply to this comment

By face (32507)
on July 1st, 2014

Please stop with the warning the earth is getting hotter.  We know that the sun is in its hottest cycle and that an increase in solar flares hit the earth.  We know that trees remove co2 from the air yet we are increasing the cutting of trees.  We know that wild fires increase the co2 but you can’t stop them.  We know volcanoes add to co2 levels but we can’t stop them.  So what’s the answer.  There isn’t any.  It is what it is. If every country stopped driving it would do nothing to stop global warming.  The earth is changing.  The solar system is changing and man cannot do a thing to stop it.

Reply to this comment

By Harvey Spooner (Rochester, NY)
on July 4th, 2014

The only thing a good man-made climate change denier can do is to figure out a way to profit from it!

Sadly, I have kids who will have to live through this.  I will be gone, and so will all of those rich-old-white-guys who insist there is no cause for alarm.  They are capitalists, not scientists.  Note, however, that a few prominent capitalists are starting to get the message.  If only the Koch brothers and others like them cared about their kids’ lives (and grand-kids’) as much as they care about money.

Reply to this comment

By Snowball
on July 7th, 2014

That’s a Pontius Pilatus point of view. World is getting hotter and it’s our fault, whether you like it or not.

Reply to this comment

By Neo (10000)
on July 4th, 2014

With everything stated in earlier posts, has its foundations, but if one thinks to reduce climate change, it can be done to reduce CO2 from the air (atmosphere), and this is only possible by transferring from fossil fuels to renewable, but it can’t happen over night, the second step would be the planting of fast-growing species of plants as raw material for the trees (because they need a long time to grow), if it is used by fast-growing species of industrial or any other hemp and other fast-growing plant mass, if it shall not would be subject to the laws in general, but would be free planted by all, would reduce CO2 in the atmosphere as well as a temperature that would stop further melting of permafrost and the consequences there of, with the continuation of seasonal plantings such as industrial hemp, every year this kind prezerve enormous amount of carbon back into the biomass, and returned to the lithosphere indirectly and directly ... in time future would likely rise to Mechanisms that are less destructive to the climate ... but the reduction of greenhouse gas emissions can be achieved by fast-growing species such as hemp, returning such plants in the earth’s ecosystem as free plants, which is not subject to any regulations, would reduce carbon saved to wood which are currently a source of cellulose that can take over other biomass, as well as many undiscovered benefits in the accumulation of carbon in plants and also in the earth itself, slowing climate change, and in same time alternative energi, also reduce greenhouse effect.

Reply to this comment

By James Richard Tyrer (Green Valley, AZ, 85614)
on July 5th, 2014

You talk about Carbon Dioxide concentration in the atmosphere but don’t mention actual Global Warming or Climate Sensitivity.  So, you push the Green agenda that we have to do something about Carbon Dioxide, but don’t talk about current climate science.

However, as shown by the NASA Remote Sensing Satellite data for the bottom of the Troposphere air temperature, the average global temperature has not shown any trend for the past 17 years.

https://wattsupwiththat.files.wordpress.com/2014/04/clip_image002.png

As you should know, Global Warming is the result of Climate Sensitivity, not just Green House Gasses.  Without positive feedback due to water vapor and low level clouds, an increase in Carbon Dioxide concentration in the atmosphere would cause only a slight increase in average global temperatures compared to the amount of Global Warming currently attributed to it.  Now some scientists believe that this feedback has changed and with it the sensitivity of the climate to GHGs has been reduced.  This could mean that the warming isn’t going to start again, at least not anytime soon.

An interesting paper published in Science:

CONTRIBUTIONS OF STRATOSPHERIC WATER VAPOR TO DECADAL CHANGES IN THE RATE OF GLOBAL WARMING

http://www.sciencemag.org/content/327/5970/1219.full

[free with registration, membership not required]

These points are science.  If this website is really about science and not about politics, you should consider these points and discuss them.

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