CO2 Levels Highest in Human History
Carbon dioxide reaches 400ppm milestone
By John Johnson, Newser Staff
Posted May 10, 2013 5:40 PM CDT
A coal plant at sunset in Emmett, Kansas.   (AP Photo/Charlie Riedel)

(Newser) – Scientists have been anticipating this milestone for a while, but they won't be breaking out the champagne now that it's here: Carbon-dioxide levels in the atmosphere passed the mark of 400 parts per million yesterday for the first time in human history, reports the BBC. The National Oceanic and Atmospheric Administration made the declaration based on readings of the heat-trapping gas at a station on the Mauna Loa volcano in Hawaii. (Another monitoring program run by the Scripps Institution of Oceanography hasn't quite gotten to 400 yet, but it supports the NOAA figure and chalks up the difference to a technicality.)

A few reactions:

  • New York Times: It's "just an odometer moment in one sense, but also a sobering reminder that decades of efforts to bring human-produced emissions under control are faltering."
  • National Geographic: "The last time the concentration of CO2 was as high as 400 ppm was probably in the Pliocene Epoch, between 2.6 and 5.3 million years ago. Until the 20th century, it certainly hadn't exceeded 300 ppm, let alone 400 ppm, for at least 800,000 years."
  • “It symbolizes that so far we have failed miserably in tackling this problem,” says the NOAA's Pieter P. Tans.

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May 17, 2013 4:21 PM CDT
"I_was_thinking" was thinking that "I_hate_to_say" sounds a little too reasonable and effective in fighting the denialist junk science being peddled by paid trolls on newser. So I will issue the same invitation which I have issued to every other global warming skeptic on newser who denies that 97% of qualified climate scientists have concluded human caused CO2 is the culprit . Because I have been so effective on newser, it behooves the science denying agenda of "I_was_thinking" to put up a link to a "source" that spreads the kinds of skepticism/propaganda that Exxon-Mobile and the Koch Brothers have spent over $100 Million to peddle through corporate controlled media over the past 15 years. The Wall Street Journal is a Murdoch controlled enterprise with exactly the same right wing agenda as Fox News, Rush Limbaugh, etc. Nice try, "I_was_thinking." If you have any credibility whatsoever you will email me at the address provided on my profile and enter into a discussion that is not protected by the anonymity that cowardly paid trolls hide behind.
May 14, 2013 9:28 PM CDT
It is ill-informed to believe that doubt of "man made" global warming is the same as climate change. While many doubt "man-made" as the primary causation, few would deny that climate change is occurring now, has occurred in the past, and will occur in the future. Many well educated, well informed scientist doubt "man-made" global. A simple web search will show this, ex.
May 14, 2013 9:23 PM CDT
I wonder how they checked CO2 levels 5 million years ago ?