Earth’s Atmosphere: A Thin Blue Line, Not an Endless Dumping Ground for Carbon Pollution

By Tom Yulsman | June 2, 2014 5:18 pm
thin blue line atmosphere

The moon seems to float atop the thin blue line of Earth’s atmosphere in this photo taken on July 20, 2006 over the South China Sea by an astronaut aboard the International Space Stations. Blue light is scattered by atmospheric gases more than other wavelengths of light, thus giving the atmosphere a blue halo. (Please see other ‘thin blue line’ images in the gallery below. Source: NASA)

As debate over regulations proposed by the Obama Administration today to reduce emissions of heat-trapping carbon dioxide inevitably becomes shrill, you might keep in mind the image above, and six others in the gallery below.

They dramatize an important fact: Our atmosphere is not an endless dumping ground. In fact, when seen from the vantage of space, it looks like not much more than a thin blue line.

By 2030, the proposed regulations would cut carbon emissions from U.S. power plants by 30 percent below 2005 levels. That cut would result in 2 billion fewer metric tons of carbon dioxide being dumped into the atmosphere each year — an amount equal to the emissions from powering more than half the homes in the United States.

But the ambitiousness of the plan depends quite a lot on how you look at it. U.S. carbon emissions have actually been declining without the proposed rules, and we’ve made a quite a lot of progress. In fact, as of 2013, energy-related emissions were already nearly 10 percent below 2005 levels, thanks to a switch from coal to natural gas for producing electricity, as well as gains in energy efficiency, increased use of renewable energy, and the Great Recession of 2007-2008.

I’ll have more to say about this in a post later in the week. But for now, I thought I’d take this visual approach (make sure to enlarge the images):


Thunderclouds Atmosphere and SunCrescent Moon Earth's Limb and AtmosphereClouds and Atmosphere from Space ShuttleClouds Atmosphere and MoonCrescent Moon and Earth's AtmosphereNoctilucent Clouds Earth's Limb and AtmosphereSunset from Space Shuttle Columbia and Atmosphere

I think you’ll agree that the images are stunning in their own right. But I think they also can help us wrap our minds and hearts around a salient point: In a relatively brief period of time, we humans have managed to fundamentally alter the chemistry of one of our planetary life support systems: the Earth’s atmosphere. In so doing, we’re running increasing risks from climate change.

atmosphere blue line

Source: U.S. EIA

So, just how big a step forward is the Obama Administration proposing to take? How much of a difference will it make to the atmosphere? More about that in a day or so.

But for a preview, click on the thumbnail at right from the U.S. Energy Information Administration. It shows projections for world energy-related carbon dioxide emissions out to 2040, for the developed nations (OECD) and still developing nations (non-OECD).

We still have a lot of work to do.

  • Das Dabu

    You would think that a science magazine would know that carbon is NOT pollution. Politics.

    • Fred funk

      Indeed, and the nerve of them to dispute that the world is 6000 years old. Tyranny.

      • Das Dabu

        LOL, talk science and you insult. Thats all you have to offer.

      • Tom Yulsman

        Fred: Mr. Dabu (or whatever his real name is) did not say anything about the world being 6,000 years old. So please debate him on the facts and leave the ad hominem attacks for another blog. They’re not welcome here.

        • Fred funk

          Are you aware that many, perhaps the majority of “commenters” on sites like this are paid shills for groups financed by big oil? Treating them as legitimate commented and engaging them lends them an air of credibility that they don’t deserve. The burden of rebuttal rests with the climate change deniers. Until they come forward with more than ridiculous conspiracy and half truths financed by the handful of scientists on their payroll, they should absolutely not be debated, but instead ridiculed.

          • Tom Yulsman

            Fred: If you want to ridicule people, I ask politely that you do it somewhere else. I don’t care what the rationale might be for doing it. It is simply not welcome here.

          • Buddy199

            Those deniers really steam your beans.

      • Buddy199

        You know, running through a field of straw men with a flame thrower also causes CO2 to rise.

    • Tom Yulsman

      My dictionary defines pollution in this way: “the presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects: the level of pollution in the air is rising.” The true politics here is to deny the overwhelming body of science showing that anthropogenic carbon dioxide has no harmful effects.

  • Uncle Al

    A social advocate makes virtue of failure. The worse the cure the better the treatment – and the more that is required. The Carbon Tax on Everything must be doubled, trebled. Revelation 22:7 can be gauged, renormalized, perturbation theoried, dualed, promoted into higher dimensions, exhaustively peer reviewed and published until is true.

  • Rick

    80% of the atmosphere is below -10 miles-. Think about that for a moment. You probably drive further than that every day…

  • Fred funk

    Science is to conservatives what kryptonite is to superman…

    • Buddy199

      Liberals, like conservatives, tend to believe the science that supports their ideology. For many liberals, the unscientific belief that GMO’s are dangerous fits their anti- big business bias. Conservatives tend to believe that the gloom and doom with climate change is vastly hyped considering the apocalyptic predictions made over the past couple of decades have failed to materialize as predicted.

      • Tom Yulsman

        Buddy: You are right that people employ science to argue from their pre-determined ideological positions. I’d add that on the issue of climate change, politics has become thoroughly scientized. But you give conservatives a pass here. (Perhaps because you lean toward a conservative point of view? ;-) )

        • Buddy199

          The majority of conservatives recognize that global temps have increased in fits and starts approx. 1.5 C over the past 150 years as CO2 levels have increased steadily. They just think that there are a number of factors other than human generated CO2 at play. That the models have been very inaccurate. That the catastrophism isn’t justified due to the lack of an uptrend in extreme weather events. And they certainly disagree with the policy “fixes” that would hurt economic growth and peoples lives. Call us crazy,

          • Fred funk

            We are still waiting for your peer-reviewed science. Cut and paste info from opinion pieces written by Koch Bros. groups are amusing, but simply reinforce the fact that you lack any credibility.

          • Buddy199

            One word: de-caf.

          • Tom Yulsman

            Hold on now. Technically speaking, is that two words connected with a hyphen? Well, uhm, I guess not. (Maybe I need some too?)

      • Fred funk

        False equivalency. How emabarssing for you.

  • dlmullan

    Discover discredited itself with this article. No science there. How about interviewing Piers Corbyn? Ben Davidson Or, Dr. Pierre Latour? i guess real science that isn’t politically motivated by the corrupt UN is too much to ask for in a science magazine…

    • Fred funk

      Post the citations for their peer-reviewed articles. Oops, they haven’t published any peer-reviewed research. How embarrassing for you.

    • Fred funk

      You tube….lol.

    • Tom Yulsman

      Piers Corbyn is not a climate scientist. He conducts no climate science research, and he does not publish in peer-reviewed climate science publications. His ideas are actually beyond wacky. He claims to be able to predict the weather many months hence based in large measure on solar activity — claims that are laughable on their face but have also been debunked. He says there is no evidence that CO2 influences climate in any way, a view that is akin to saying that there is no evidence for biological evolution, or that there is no evidence that gravity is created by mass warping the fabric of spacetime.

      As for Discover “discrediting itself with this article”: First, Mr. Dlmullan, or whatever your real name is, this is a blog. Discover hosts it. But it is my product, and no editor from Discover approves what I write before it is published. Second, there is actually nothing in this post that brings discredit to the magazine. Lastly, and most important: If you consistently don’t like what I present here, you might consider finding a blog that is more in synch with your own biases, as opposed to one that might challenge you to think outside your comfort zone.

      • dlmullan

        well someone should approve it… and i use my real name b/c i am not fake or a shill. i do not like people on their blogs or anyone else’s posting fake or misleading information and that is what this is. i am educated and astute. why should i leave when i have done nothing wrong but point out the false claims of a writer?

  • OWilson

    Oh hum, the luddite march towards doomsday continues.

    It’s always “increasing risks”, some 10, 50 or a hundred years from now.
    Doomsday projections never materialize, but there’s always next year.

    Repent, give up your worldly goods and ye shall be saved”.

    This stuff was old a thousand years ago.

    By the way what does that last 35 years of satellite data show, vis a vis temperature, sea level rise, and polar ice cover.

    To much science there?



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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