Atmospheric carbon dioxide concentrations have crossed a new threshold, the UN's weather agency said Monday, highlighting the urgency of curbing manmade, climate-altering greenhouse gases.
In April, for the first time, the mean monthly CO2 concentration in the atmosphere topped 400 parts per million (ppm) throughout the northern hemisphere, which pollutes more than the south, the World Meteorological Organization (WMO) said.
"This should serve as yet another wakeup call about the constantly rising levels of greenhouse gases which are driving climate change," WMO chief Michel Jarraud said in a statement.
"If we are to preserve our planet for future generations, we need urgent action to curb new emissions of these heat-trapping gases. Time is running out," he warned.
Spring values in the northern hemisphere had previously spiked over the 400 ppm level, but this was the first time the monthly mean concentration of CO2 in the atmosphere exceeded the threshold.
The global annual average is set to exceed the 400 ppm level in 2015 or 2016, the agency added.
The threshold is of symbolic and scientific significance, and reinforces evidence that the burning of fossil fuels is responsible for the non-stop increase in heat-trapping gases, the WMO underlined.
CO2 stays locked in the atmosphere for hundreds of years, and its lifespan in the oceans is longer still.
It is by far the most important greenhouse gas emitted by human activities and was responsible for 85 percent of the increase in radiative forcing, the warming effect on the climate, from 2002-2012.
According to the WMO, the concentration of CO2 in the atmosphere reached 393.1 parts per million in 2012, or 141 percent of the pre-industrial level of 278 parts per million.
The amount of CO2 in the atmosphere has increased on average by two parts per million every year for the past decade.
Explore further:
Historic carbon peak soon to become global average, WMO says

hurricane25
1.8 / 5 (20) May 26, 2014BaconBits
4.4 / 5 (20) May 26, 2014By your idiotic logic human average has been declining because the tallest man lived 80 years ago when in fact, the average height has been increasing. Cherry picked baselines don't win your argument they reveal your intention to deceive.
Captain Stumpy
4.5 / 5 (17) May 26, 2014BaconBits has it right
you see the world like this: http://www.skepti...rame.jpg
whereas SCIENCE will see this: http://www.skepti...rame.gif
this is taken from an article here: http://www.skepti...php?g=47
cantdrive85
1.4 / 5 (18) May 26, 2014https://www.youtu...rwwT6Zps
At least we can rock some badass tunes while we burn....
tommo
4.2 / 5 (15) May 26, 2014Benni
1.8 / 5 (20) May 26, 20143432682
1.9 / 5 (17) May 26, 2014PinkElephant
4.1 / 5 (17) May 26, 2014All aboard the denial Escalator!
http://www.skepti...php?g=47
wheeeeee, what fun...
hurricane25
1.5 / 5 (16) May 26, 2014A case could be made we're within the 50's through 70's again, but the positive forcing should be so strong now comparably it would take a far larger negative to be the reason for the stall. Why don't you alarmist consider the evidence all around you and hone in on this a little? Just saying that all debate is over is silly.
Caliban
4.5 / 5 (16) May 26, 2014PE --do you mind?
hurricane25--
Can't you understand a simple graphic depiction of the duplicitous nature of the claim you are making? PE has already shown it you once, but since you obviously either missed it or didn't understand it, please --have a(nother) look:
http://www.skepti...php?g=47
...now do you get it?
Whydening Gyre
4.3 / 5 (9) May 27, 2014That might explain previous observations of CO2 rises FOLLOWING warming trends. Anybody checking methane levels?
PinkElephant
4.8 / 5 (16) May 27, 2014http://woodfortre...rom:1970
Aside from Spencer's advocacy, how do you explain this?
http://www.nodc.n...CONTENT/
Lastly, I'm not concerned with natural climate variability, even multidecadal cycles like the PDO and AMO. They only add wobbles around the surface temp. trend, not total heat trend. If we were to get off easy for another 30 years thanks to them, we'll only pay all that much harder and faster on the other side of the cycle in the 30 years after.
PluviAL
1.9 / 5 (9) May 27, 2014We should investigate and develop Pluvinergy for two reasons, one is to give people a solution. A second reason is that with our intensive study of climate science it has become clear that civilization will always be threatened not only by human caused climate catastrophe, but by natural variation. We need to have capacity to cool the planet or to warm it. This is what Pluvinergy claims, if it works as proposed is another matter. The point is we need solutions, not just valid scientific facts.
This is why people here cling to their escalator graphs, any little bit of support to deny reality.
Caliban
4.2 / 5 (11) May 27, 2014Okey dokey!
Let's have your link, so that we can LEARN what there is to know about pluvinergy, before we debate its relatives merits, shall we?
Is that asking too much, PluviAl?
Whydening Gyre
3.5 / 5 (6) May 27, 2014I do have a simple question - If we keep in mind this historical record - is there possibly something ELSE causing a global temp rise that we have not considered? Like - Earth itself heating up? Maybe caused by removal of an "insulating blanket" of Oil?
I know, I know - way out there...
rockwolf1000
5 / 5 (8) May 27, 2014Would the answer to that lie in cave and mine shaft temperatures? Are they recorded? Have they changed?
thermodynamics
5 / 5 (11) May 27, 2014All you have to do is to make some calculations of how temperature can change inside the earth. When I took the PE exam for Mechanical Engineering they had a heat transfer problem where they wanted to have us calculate the change in temperature with depth every year for the annual change in average temperature at the surface. It turns out heat does not travel fast through the earth. Cont
thermodynamics
5 / 5 (13) May 27, 2014rockwolf1000
5 / 5 (6) May 27, 2014Thanks.
Although I wasn't too serious about the proposal, and I don't think WG was either, it would be interesting to note if the crust is warming a little. The permafrost layer is getting deeper from the surface and I expect it is retreating towards the poles also. This would be yet another reservoir of latent heat similar to the oceans but obviously absent mixing currents and waves. Thus a much smaller & slower uptake of energy, but the value cannot be zero.
Whydening Gyre
5 / 5 (3) May 29, 2014Was a "thought" experiment...:-)
That said, we need to look at the complete cycle. "Black body" heat absorption generates higher temps causing increased liquid phase water, leading to increased water vapor, leading to higher volume of rain which "washes out" the absorptive factors and which then collect on the earths surface, get covered by the increased surface water, carried down to sea floor, leaving the water reflectivity to then "cool" the planet - Again...
Bottom line is - Earth wins, regardless of us...:-)
Maggnus
4.4 / 5 (13) May 29, 2014http://www.climat...ly-17196
http://www.washin...hivered/
http://www.weathe...20140220
But Benni the Engineer lives in the US and it was cold there! So, because he is an engineer and all, he KNOWS more then all them PAID OFF scientists FOISTING that CONSPIRACY on us!
Captain Stumpy
4.6 / 5 (10) May 29, 2014guess you forgot all about that video I linked to you already... more than once...
http://qz.com/163...n-worse/
try just THIS link... you can just watch the video...
http://www.youtub...m9JAdfcs
I don't know about Magnus, but given that you tend to ignore any evidence that does not conform to the belief that you post about here, & that you ignore as well as argue against observed and empirical data, and that you continually misrepresent climate science...in times like this I find it very difficult to believe that you are an engineer.
Eddy Courant
1 / 5 (6) May 31, 2014ubavontuba
1 / 5 (9) Jun 01, 201410? Only 10? Where have you been? It's been much longer than that. Try 18 years!
http://www.woodfo....3/trend
ubavontuba
1 / 5 (9) Jun 01, 2014Have you ever really examined that chart? Did you know the previously longest step only lasted eight years? We're more than double that now.
ubavontuba
1 / 5 (9) Jun 01, 2014Did you know the oceans have actually been cooling for more than a dozen years?
http://www.woodfo....3/trend
Caliban
5 / 5 (6) Jun 03, 2014Damn, ubybooby --that's really weird, since they've been heating rapidly for the last 6 years!
Looky:
http://www.woodfo....3/trend
Cherrypicking moron.
thermodynamics
5 / 5 (6) Jun 03, 2014What I would like to see from you is a post of any reliable source that shows a "pause" in heating. Your posts show a slow down in warming for the sites that measure surface temperatures. What others have pointed out to you is that those temperatures are not indicative of the heating that can go on by melting ice (isothermal) or heating oceans (high heat capacity).
The concept of the greenhouse effect is that it traps heat, in the form of IR, within the atmospheric envelop. So, that heat goes into heating the earth.
Can you show one link that shows the earth is not being heated as time is marching on?