Counting Carbon

By Keith Kloor | March 1, 2011 4:30 pm

Ever wonder how scientists can determine how much carbon dioxide (CO2) is accumulating in the atmosphere? In this engaging story, science writer Tom Yulsman visits a CO2 monitoring station high up in the Colorado mountains and brings a crucial part of climate science down to earth. Here’s the scene and a snippet of how the data is collected and analyzed:

From a two-room structure in a clearing on the forested slopes of Niwot Ridge, [NOAA’s Duane] Kitzis regularly fills cylinders with ambient air. Then he hauls them back down the mountain to a NOAA lab where infrared analyzers are used to determine with exquisite precision the air’s chemical composition.

These samples are then sent out to the global network of monitoring sites. Since the makeup of each one has been determined to very fine precision, the different groups can use them to verify that their own instruments are providing accurate readings.

In this way, the air Kitzis captures and analyzes is used as the “standard” against which other samples are compared, enabling atmospheric monitoring of CO2 concentrations around the world to be done precisely and in coordination.

I am an empiricist,” Kitzis says. “I like instruments and measuring things.”

But how can Kitzis and his colleagues make sure that everything is kosher in their own lab? Here, the system gets even more complicated, with multiple internal calibrations involving two different sets of cylinders, some of which were collected on Niwot Ridge 25 years ago. (For the gory details, see this publication from NOAA.)

Thanks to these meticulous efforts, there is no scientific doubt about what is happening to the atmosphere.

“We are very certain about the increase in CO2,” [NOAA’s Pieter] Tans says. “In fact, it is the thing that is most certain in our knowledge about climate change.

As someone who once sent Yulsman out to report similar stories (here is one of my favorites), I can tell you that he’s got a knack for distilling the science conducted at high elevations. So go have a look at his latest.

CATEGORIZED UNDER: climate science
MORE ABOUT: climate science
  • BobN

    Neat story.  Kinda of surprised they don’t use lab produced standards for their network but if the testin of the colorado air is rigourous then it  all should be good.

  • Jack Hughes

    This is just weird. I cannot imagine for 1 second that CO2 concentration is the same all over the world at all altitudes and all locations. It’s released in some places and absorbed in  other places.

    But this dude speaks as though there is just one number that represents the whole world.

    Am I missing something? I know that man-bear-pig is evil – but is he (she?) ubiquitous as well?

  • Howard

    You have got to be kidding.  This is the simplest job in the world and Yulsman makes it sound like Kitzis is Jesus Christ and Albert Einstein rolled into one.

    You journo’s cream your jeans for this?  Mid 20th century analytical technology and 18th century field techniques?

    No wonder you swallow the RealKlimate hysteria.

  • Brandon Shollenberger

    The responses to this post are rather strange (exclude BobN’s).  They give the impression of having not read the story being discussed.  For example, I have absolutely no idea how anyone could think the story made it sound like Duane Kitzis was Jesus, Albert Einstein, or any combination thereof.  In actuality, the article was exactly what it should be, and I’m glad Keith Kloor posted a link to it.  My only regret is I already knew a bit about the topic, so the article didn’t really teach me anything.

    Also, Jack Hughes, if you read the story, you will find an answer to your comment.  The work by Kitzis isn’t meant to be some end-all result regarding CO2 levels.  The reason his work is important is it basically sets the standards for the hundred plus sites which measure atmospheric carbon dioxide.  His work helps ensure the conclusions about CO2 levels are rigorous.

  • Howard

    Brandon, I admit a little hyperbole… however, the quote:
    “this is arguably one of the most important environmental jobs on the planet.”
    …about someone who puts air in bottles over and over and over again is a bit rich, don’t you think?  In the real world, we use auto-samplers for this type of mind-numbing drudgery.

    Also, what is there to learn?  His Cat needs a tune-up.  He has an exceedingly boring job that an 8th grader could do.

  • Brandon Shollenberger

    Howard, that wasn’t hyperbole.  Hyperbole is exaggeration.  Exaggeration requires there be some basis.  Nobody ever acted as though Kitzis’s job was particularly intelligent or insightful, and they certainly didn’t act as though it was divine or messianic.  It was simply described as “arguably the most important.”

    That aside, you seem to think the most important environmental job needs to be flashy or something.  There’s no reason for that.  Increasing carbon dioxide levels has been one of the single most important pieces of evidence for global warming.  In part, that evidence is made valid by the rigorous work done by Kitzis.

    Maybe this doesn’t make his job “one of the most important environmental jobs,” but it certainly could be argued that it does.

  • Howard

    Almost every other of the millions of environmental jobs are more important and are not flashy. Think turd-plant operator.

  • Steven Sullivan

    No, *you* think that.  I’m guessing it’s more natural for you.

  • Brandon Shollenberger

    Howard, why would you directly contradict what I said without actually responding to what I said?

  • Howard

    Right ho Steve.  *I* think that the biggest sources of pollution are the highest priority.  My guess is that since it is handled for you quietly and efficiently, you conclude that the underlying problem has evaporated into thin air.  As Grandpappy used to say: “Wish in one hand and poop in the other and see which one fills up first”

    Brandon:  I was just trying to save myself time and you further embarrassment.

    OK Kids.  Picture this.  Stop all climate related research for 10-years or stop treating water and wastewater and the collection of trash for 10-years.  Which action results in more death and disease at the end of that time?

  • Brandon Shollenberger

    Howard, it makes no sense to go from discussing one job to discussing all jobs.  Your scenario isn’t even remotely applicable.

    As for embarrassment, I have no idea what you think you could save me from, but really, it seems like you’re just making things up again.

  • Lazar

    Well written. Appropriate level for the layman with lots of cites for those who wish to investigate further. Loved the bit about the airdale on the back of the cat, the kind of detail I won’t find in journals. Thanks Keith for linking this!


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About Keith Kloor

Keith Kloor is a NYC-based journalist, and an adjunct professor of journalism at New York University. His work has appeared in Slate, Science, Discover, and the Washington Post magazine, among other outlets. From 2000 to 2008, he was a senior editor at Audubon Magazine. In 2008-2009, he was a Fellow at the University of Colorado’s Center for Environmental Journalism, in Boulder, where he studied how a changing environment (including climate change) influenced prehistoric societies in the U.S. Southwest. He covers a wide range of topics, from conservation biology and biotechnology to urban planning and archaeology.


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