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Earth Science

CO2 Levels Reach 400ppm at Mauna Loa For First Time On Record 497

Titus Andronicus writes "Today, NOAA reported, 'On May 9, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 parts per million for the first time since measurements began in 1958.' For comparison, over the last 800,000 years, CO2 has ranged from roughly 180 ppm to 280 ppm. 'For the entire period of human civilization, roughly 8,000 years, the carbon dioxide level was relatively stable near that upper bound. But the burning of fossil fuels has caused a 41 percent increase in the heat-trapping gas since the Industrial Revolution, a mere geological instant, and scientists say the climate is beginning to react, though they expect far larger changes in the future.' The last time Earth had 400 ppm was probably more than 3 megayears ago."
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CO2 Levels Reach 400ppm at Mauna Loa For First Time On Record

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  • LOL (Score:2, Interesting)

    by Anonymous Coward

    Megayears? Someone trying to sound smarter than they are?

  • by Anonymous Coward on Friday May 10, 2013 @06:01PM (#43689671)

    i hope there's a special place in hell for people who spent the 70's til present denying climate change - you know who you are. Unfortunately it will be the same place in hell as everyone else when it gets too hot around here.

    • So I don't want to add to the debate around whether or not global warming is actually occurring or not but just assume that it is. How exactly is global warming bad?

      So glaciers melt - they have melted before and came back in a few million years there is no reason to believe that this will not occur again. So we lose access to them now but this would happen eventually anyway. Sure not in our lifetimes but across the millions or billions of years before the sun kills the planet completely ice will come a

    • by rusty0101 ( 565565 ) on Friday May 10, 2013 @10:13PM (#43691715) Homepage Journal

      As pointed out by Lionel Dricot at [], there is a cost of changing your position. A large number of climate deniers have invested themselves in the position they have taken, and unless they can find a benefit to changing their position that outweighs the investment they have made, they are likely to stand firm in their state of denial.

      Potentially a far more useful technique, than bashing them over the head with the facts, is to start by having them review the facts surrounding the level of CO2 in the atmosphere, and then ask them to provide proposals as to why those levels have changed in the timeframe they have. That engages them in the process of actually doing science, as once they have proposed a hypothesis as to what may be causing an increase in CO2, those hypotheses can be tested. (I.e. it's the destruction of the rainforest - what does satellite data show about the circulation of O2 generated in the rainforest? It tends to stay in the area of the rainforests. Volcanoes emit CO2! Have we seen a tremendous increase in volcanic activity in the past century? No. Etc.) Start getting them to invest in looking at possibilities that can be tested, rather than having them try to change their minds based on decisions they have invested in.

      Nah, it probably won't work, but it seems to me to be better than trying to sit and debate the topic with people who've come to the table already decided that no matter what the logic of proof that's provided, they are not going to change their position.

    • The 1970's climate scare was global cooling, which was ultimately dropped as incorrect. That gives a large precedent to not caring about (regardless of denying or not) the next climate scare.

      • by rve ( 4436 )

        The 1970's climate scare was global cooling, which was ultimately dropped as incorrect. That gives a large precedent to not caring about (regardless of denying or not) the next climate scare.

        Global cooling incorrect? Ice ages are a theory very well supported by evidence. As long as there are still permanent ice caps on the poles and glaciers in the mountains, there is no indication whatsoever that the holocene is a 'post' glacial. We are 10000 years into an interglacial, which on average have been lasting about 10k years. The 'flips' between glaciation and interglacial are very sudden (on a geological scale) after a period of slow decline. This wasn't a baseless climate scare, because there is

  • Dupe (Score:5, Informative)

    by Hentes ( 2461350 ) on Friday May 10, 2013 @06:05PM (#43689715)

    Dupe [].

    • NOT Dupe (Score:4, Informative)

      by alexhs ( 877055 ) on Friday May 10, 2013 @07:10PM (#43690317) Homepage Journal

      Actually this is a follow-up :

      2013-05-05 : "individual observations [...] have exceeded 400 parts per million" "The daily average observation has crept above 399 ppm" "the daily observation will break the 400 ppm milestone within a few days"
      2013-05-09 : "the daily mean concentration of carbon dioxide [...] surpassed 400 parts per million"

      Of course, Soulskill should have referenced timothy, they were obviously aiming for the dupe, but new data arrived in the meantime.

  • The summary seemed to lead in a specific direction - the 'for comparison' referring to 800k years isn't based on info from other types of measurements, pre-1958 at that site.

    Interesting bits from the Mauna Loa wiki []
    - It's a volcano
    - It's been erupting for at least 700k years
    - It may have emerged above sea level 400k years ago
    - Oldest dated rocks are less than 200k years old
    - It's drifting away from the hotspot and will go extinct in the next 500k=1m years
    - It erupted last from Mar-Apr of 1984
    - Atmosphere obs

  • by kenh ( 9056 ) on Friday May 10, 2013 @06:27PM (#43689933) Homepage Journal

    No less an authority than the United Nations pins a full 9% of all human-related CO2 production on cows, but it's worse than that:

    When emissions from land use and land use change are included, the livestock sector accounts for 9 per cent of CO2 deriving from human-related activities, but produces a much larger share of even more harmful greenhouse gases. It generates 65 per cent of human-related nitrous oxide, which has 296 times the Global Warming Potential (GWP) of CO2. Most of this comes from manure.

    And it accounts for respectively 37 per cent of all human-induced methane (23 times as warming as CO2), which is largely produced by the digestive system of ruminants, and 64 per cent of ammonia, which contributes significantly to acid rain.

    Source: Rearing cattle produces more greenhouse gases than driving cars, UN report warns []

    • by bug1 ( 96678 )

      Or it our fondness for beef...

      Yes please, we blame it on the cows and not the people.

      Now we just have to kill all the cows and livestock, then i can use all my fossil fuels until I have none left.

      Because what we really need in this debate is more excusses.

    • Very interesting, but I'm having a hard time making sense of the numbers - not an expert. All the figures stated are relative, and not always relative to each other. What I would like to know: what percentage of the combined global warming potential (or CO2 equivalent) of all greenhouse gases can be attributed to livestock? Not in % of methane, % of CO2, % compared to transit pollution, etc.

      I did try to find that information in the source you linked, but failed. I also downloaded the "full report" from 2

  • Experts fear that humanity may be precipitating a return to such conditions — except this time, billions of people are in harm’s way.

    Are climate scientists really the best people to decide what to go about global climate change? They study the effects and may be able to predict things like rise in temperature, oven levels, ocean acidity and things like that, but they only solution they seem to propose is that we stop emitting carbon dioxide. Isn't it possible that other lifestyle changes could m

  • Am I the only person worried about the macadamia nuts?

  • Am I the only one that thinks taking CO2 concentration measurements near one of the most active volcanic regions in the world is not such a good idea? Not saying the measurements are wrong, it just seems like they could have picked a better spot...

  • In my greenhouse (for medical marijuana) the CO2 is increased to 3000PPM. The plants love it and produce some of the most potent bud I've ever smoked.

    Point is -- we need more medical marijuana and industrial hemp to suck up the extra CO2 from the atmosphere. Hemp and algae are the best ways to remove CO2 from the air. And unless you know of someway to get high off algae, I say let's go with reefer.

  • 800,000 years out of 4+ billion years is a drop in a bucket.
  • [] (from 2008)
    "The record clearly demonstrates that [CO2 levels were] significantly higher than usually reported for the Last [Glacial] Termination, with levels of up to ~425 ppm about 12,750 years ago, which exceeds the present CO2 concentration of 395 ppm."

    This explains thoroughly that
    a) it's fundamentally a fallacy to compare Vostok data with Mauna Loa CO2 results (from 3000+ m altitude), and
    b) that CO2 values frequently exceeded 400 in both this and the last ce

  • by Chas ( 5144 ) on Friday May 10, 2013 @10:04PM (#43691663) Homepage Journal

    Hello? Seven BILLION people?
    And enough livestock to actually feed a good chunk of them?
    Hell, the planetary population only two billion in something like 1925?
    Yet we've nearly quadrupled population in the last 90 years?
    Roughly half of which live in central and eastern Asia? Countries where their pollution output would shame early 20th century industrialists?
    Yeah, fossil fuel has a good deal to do with it. But let's not pretend the sheer mass of humanity itself isn't contributing greatly to increased CO2.

  • by DJ Particle ( 1442247 ) on Friday May 10, 2013 @10:07PM (#43691669) Homepage
    ...the fact that there are 7 times as many humans on Earth as there was even a couple hundred years ago.

    Not saying fossil fuels aren't contributing, but surely the population issue has to be a contributing factor too.

"Mach was the greatest intellectual fraud in the last ten years." "What about X?" "I said `intellectual'." ;login, 9/1990