Aviation A Smaller Contributor To Climate Change Than Previously Thought


Aviation has a smaller impact on climate change than previously thought but it’s also growing rapidly and its effects are more complex than other contributors according to a new study. A team of European climate scientists has recrunched the numbers and determined that aviation is responsible for 3.5 percent of the global warming effect that results from human activities. Previous estimates pegged the aviation contribution at about 5 percent. The new data takes into account some balancing factors in the ways that aircraft pollute.

For instance, nitrogen oxides emitted in aircraft exhaust increase the production of ozone, a major greenhouse gas, but they also destroy methane, a big contributor to atmospheric warming. Also contrails heat and cool the planet at the same time by trapping atmospheric heat while reflecting sunlight. The net result is that contrails are only about half as bad as previously thought. The scientists say that despite the findings, aviation still needs to clean up its act and the COVID-created hiatus in aviation activity isn’t going to help much. “It’s not going to make much difference in the long term,” said researcher David Lee at Manchester Metropolitan University in the U.K.

Russ Niles
Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.

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  1. Never doubt a “scientist.” They always are right; anyone who would doubt or even question them is a Neanderthal “denier.”
    For 45 years, I made a very nice living designing things that “experts” said could not possibly exist. All without living in Missouri.
    Go figure.
    So what, if the expert climate scientists were off by a mere 43%? On the other hand, are the new figures any more believable than the old ones? I guess if they experts say they are, then they must be. Right?
    God save us all from High Priests, um… experts.

  2. Totally agree with YARS.. Scientist notoriously align themselves, and their research, with whatever funding money is available.. Astonishing, even scientist succumb to the influence of money and notoriety.. But, the real shocker, is how naive and assuming people really have become..

  3. The only way to stop these wild speculations that cost us billions in wasted effort is to fine these people personally for those costs. Right now they can screw with the nations economic system without consequence. It’s time they become Personally accountable for damages.

  4. Everyone has their biases and agendas. The specialist or “scientist” can reliably be counted on to produce output that dovetails with their own, or their group’s, established biases and agendas. Our politicians in turn will embrace or ignore the output of those specialists depending on whether it advances or hinders their own personal agenda. Our task, then, is to evaluate the effect of the biases and agendas of others on the final result while simultaneously acknowledging and compensating for our own. Not an easy task, particularly the final step.

  5. It was scientists (and engineers) who brought WWII to an end; gave us antibiotics; showed the world how to get to the moon, and back; improved weather forecasting by two orders of magnitude; developed the semiconductors that created the world we live in today.

    Really want to show your contempt for scientists? Flush your statins and beta-blockers down the toilet. Toss your GPS into a dumpster. Take an oxy-acetylene torch to your cell phone.

    Scientists suffer from the human failings all of us do: arrogance, gullibility, narrow mindedness. But the profession has earned its right for our respect.

    • Kim, what’s the matter with you? Don’t you know that reason and logic like like that have no place on AvWeb? This is a place for armchair quarterbacks and jaded people who think they know more than actual professionals.

    • With apologies to Frank Borman, scientists (like the rest of us) have to earn their wings every day.
      When BS is fed to us as fact; when we’re told that if we question the BS, we’re “deniers,” respect becomes a fast casualty of the fact wars.

      I respect scientists. I deplore BS. One of the things that facilitated my career as an engineer, was a keen gift for discriminating between science and BS. Too bad that gift is such a rare thing among our “leaders.”
      (Just to be clear, Kim, I’m not talking about you – for whom I have profound admiration and respect.)

  6. Yes, everyone has their biases.

    It’s amazing that the first few commenters seem to think that scientists (who devote their life to a profession that requires years of difficult self-disciplined study for average pay and little recognition) have anywhere near the bias of politicians or conspiracy theorists, known for having relatively little education or self-discipline.

    Clearly the world would be a much better place if we would just listen to all the untrained people and avoid the opinions of all these people who dedicate their lives to deeply studying an issue according to a transparent and reproducible logical framework.

    • As the very first poster in this thread, I now apparently have to point out that my comment did NOT even MENTION the idea of bias. I just pointed out that those devoted experts changed their tune – by 43%. That’s not some rounding error. It’s emblematic of a fundamental flaw in the “science.”

      As Ronald Reagan famously said: “Trust. But verify.”
      As I less-famously said: “Scientific consensus is an oxymoron.” And this one: “Beware the folly of conflating education with intellect.”

      • “Scientific consensus is an oxymoron.”

        You’re either being disingenuous, don’t know what you’re saying, or are being intentionally misleading.

        There are plenty of subjects that scientists have reached consensus on, including, but not limited to: evolution, relativity, and the fact that earth is warming, primarily due to human activity.

        Scientists can discuss the degree of these effects, economists can discuss trade-offs, and politicians can discuss what-if anything-to do about them. But they’re incontrovertible facts.

  7. Anti-vaxers base their misguided opinions on defrocked physician/fraudster Andrew Wakefield, the now unlicensed “scientist”, who sold his soul to Big Pharma for ££. Unfortunately his conduct and the failure of the peer review system to expose it before it was in the public domain castes a shadow on all scientific research.

    CNN and Fox News routinely spew intentionally biased data that should never be considered scientifically accurate. True scientific research (i.e. that which is reviewed by and published in reputable journals) remains our best hope for the most reliable information available on any given subject at any given time. Unfortunately, this information is sometimes hard to find.

  8. It is important to remember there is a huge difference between careful, coordinated research leading to theories which actually prove out in the end and simply throwing fistfuls of data at the public, data that is culled to advance a theory that some group is committed to. Unfortunately, the nation is embroiled in just this sort of data food fight over multiple not-yet proven theories which are offered by their proponents as established fact. Come back when it is all over and careful, peer-reviewed analysis of what transpired can be done, then we’ll really know something. Maybe.

  9. But remember. We’re talking about chemtrails. All those airline and military pilots are up there spewing mind-control formulas to advance the eventual triumph of the Deep State. Why, they’re even poisoning the minds of their own children!

  10. Perhaps my comment would be easier for you to understand, if it were expressed as “consensus science.” Either way, it indeed is an oxymoron. Consensus does not make ANYTHING true or “incontrovertible.”

    Scientific consensus held that the world was flat. (It is not.) Scientific consensus held that the Earth was the center of what we now call the solar system. Oops.

    In 1975, Newsweek warned us about global cooling.

    The wonderful thing about REAL science, is that it eschews consensus-as-proof. Somewhere, Galileo is smiling.

  11. Pretty sure if scientists had as much faith in their predictive abilities as their acolytes do, we’d see a lot more scientists cleaning up in Las Vegas and picking winning lottery numbers.