If We Start Geoengineering, There’s No Going Back

By Nathaniel Scharping | January 22, 2018 3:14 pm
(Credit: aaltair/Shutterstock)

(Credit: aaltair/Shutterstock)

When it comes to climate change, speed kills.

The temperature changes that are causing heat waves, intense storms and other climate aberrations are dangerous today because they’re happening so fast. The climate has indeed been as warm, and warmer even, in the past, but it reached those temperature levels over the course of thousands or millions of years — long enough for the changes to occur gradually. This time around, the climate is being altered too fast for animal and plant life to adapt.

A suggested fix for climate change could make the problem even worse.

Fixing the Climate

A new paper out today in Nature Ecology & Evolution looks at how geoengineering — the concept of artificially manipulating the atmosphere to counteract the effects of climate change — would affect biodiversity on Earth. The effects are a bit mixed, but the paper’s real warning note comes from an analysis of what suddenly halting geoengineering efforts would mean. If we begin to alter the climate and then abruptly stop, the consequences would be much worse than if we had never even begun in the first place, the researchers say.

For their analysis, researchers from the University of Maryland, Annapolis, Yale University and Rutgers University assume that humankind decides to begin geoengineering in the year 2020. Governments and scientists in this fictional (though plausible) alternate universe begin injecting sulfur aerosols into the climate at the equator, to the tune of five trillion grams (5 Tg) per year.

This kind of geoengineering is called stratospheric aerosol injection (SAI) and it’s one of the most commonly proposed scenarios for geoengineering. Where carbon dioxide holds onto heat, making the planet warmer, sulfur helps to reflect the sun’s energy, meaning less enters our atmosphere and the planet gets cooler. For evidence that this works, all scientists need to do is look at volcanic eruptions, which pump millions of tons of sulfur dioxide into the atmosphere. There are noticeable dips in average global temperature following large-scale eruptions, and one of the most recent occurred in 1991 when Mt. Pinatubo erupted in the Philippines. Large parts of the planet experienced temperature decreases of almost a full degree Fahrenheit following the eruption.

Five trillion grams is about a quarter of the amount of sulfur that Mt. Pinatubo ejected, so placing that much into the atmosphere every year could be sufficient to cool the climate appreciably. The results would be beneficial on balance, at least as far as we can tell right now, though there is some worry that this kind of geoengineering might skew rainfall in harmful ways.

Don’t Stop

However, the gravest danger that geoengineering poses is that it only masks the real problem. We might spray sulfur into the atmosphere, but there would still be too much carbon dioxide in the atmosphere. Therefore, if we were to stop geoengineering, the climate would snap back to where it was before, and likely get even worse, assuming that we didn’t stop emitting CO2.

That shift wouldn’t happen on a scale of thousands of years, or even of decades, as it is now. If geoengineering were suddenly stopped after 50 years in 2070, the researchers’ analysis shows that the climate would warm by more than a full degree on land in just ten years—that’s an incredible level of volatility when considered at a global scale.

The consequences for plants and animals could be severe. In the researchers’ scenario, temperature changes are estimated to occur three times faster than if climate change had occurred at the predicted rate. That’s a temperature change greater than in any other decade in the historical record, the researchers say, and more than any predicted under the climate forecast they use.

It’s also much faster than most plants and animals can adapt. Regions that harbor some of the greatest biodiversity on Earth, such as tropical oceans, the Amazon basin, Africa and Eurasia, would be most affected, they say. Species living in these regions would face conditions that they had never before experienced and could potentially die out.

Ramping down geoengineering slowly would help to mitigate these problems—but that may not be an option. A geoengineering program would most likely be run by the government, or a coalition of governments, and would thus be subject to changes in political will. And when it comes to international cooperative agreements, nothing is ever guaranteed.

The best solution, the researchers say, is to cut greenhouse gas emissions the old-fashioned ways. To keep temperature increases within the bounds proposed by the Paris Agreement, that means emissions will need to peak by 2020.

CATEGORIZED UNDER: Environment, top posts
  • johnnysandiego

    Ha! You say “start geoengineering” as if we haven’t been doing it for hundreds of years

    • CB

      “as if we haven’t been doing it for hundreds of years”

      Thank you. Burning fossil fuels is geoengineering.

      This is geoengineering too:

      “Creating biochar actually reduces CO₂ in the atmosphere because the process takes a theoretically carbon-neutral process of naturally decaying organic matter and turns it carbon-negative: When plants decay, they emit CO₂, which other plants eventually absorb, and the cycle continues. Biochar stabilizes that decaying matter and accompanying CO₂ and puts it in the ground to stay for — potentially — hundreds or even thousands of years.”

      (Yale Environment 360, “Refilling the Carbon Sink: Biochar’s Potential and Pitfalls”, Dave Levitan, December 9, 2010)

      I’m quite frankly a bit annoyed that authors continue to pen article after article about sulfur aerosols and don’t write a single word about types of geoengineering that would actually fix the problem…

  • beefrits

    Hey Nate, are you suggesting that the know-it-alls screaming about the end of the world due to man-made global warming don’t know enough about complex ecosystems to fix them with a tweak or two? You must be a science denier.

  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    the Amazon basin, Africa and Eurasia, would be most affected
    I am prepared to make that sacrifice. Get your limp-wristed fist out of my wallet.

  • OWilson

    Children are born all over the world, with the opportunity to love, and adapt to Mother Nature and her bountiful gifts.

    Who will we elect as our God, to change the our Blue Marble Earth’s atmosphere?




    The Chairman of the U.N.’s IPCC who was fired for sexual harasement? Who got the temperature predictions wrong, back in 1990?

    Maybe the gang of corrupt tim pot dictators who run that failed Peace Organization, the U.N.? Their pals in the IPCC who’s temperature models failed at the all three scenarios?

    Especially with world agricultural food production setting new records every year, and the standard of living rising across the world!

    At least let us send a team around the world to see how it all works. No decisions made by clerics and bureaucrats in darkened DC Committee rooms, Luxemberg, or academic Ivory Towers, or General Assemblies, folks who have never had a real job in their lives! :)

    If we can’t fix Wars, Terrorism, Nuclear Proliferation, Government corruption, and the living hell of the beautuful children in America’s inner cities, who are kept illiterate and dependent, why should we trust the future of the Earth to these same folks?

  • Muhammad Aljukhadar

    I mentioned the solution to this long time ago in my blog but no one paid attention. Please read and give feedback: “These particles, which are man-made and lighter than sand because they fly via relatively fable airstreams, helps control global warming because when they are fed to the eco-system (e.g., by throwing them from a mountain-top or from an airplane in an air-active area), they (1) block the sun from hitting earth, (2) when sun-heated, they absorb carbon dioxide, becoming darker and heavier in the process, and (3) when eventually the heavier ones hit the earth back, they act as land fertilizer (and primary nutrient for sea’s algae). This product can thus be used by humans to control global warming, while helping reduce desertification.”

    • EdDemian

      Very interesting Mo. And it makes sense. However it sounds very scientific and I avoided science classes. However, I suggest that your theory should be tested in a controlled laboratory. Of course funding and press is everything. Good luck

  • Gallilao

    These Geoengineers are just more frauds trying to bilk the public and/or governments or anyone else they can find that is gullible enough to swindle. These crooks don’t know what climate is, much less be able to affect it.
    Geoengineering is the biggest scientific farce, since the creation of Climate Science and the CO2 boogeyman.
    These Geoengineering frauds should in jail, alongside those Climate Science frauds!
    The notion of geoengineering the climate is hilarious and these fools should be laughed out of town!!

  • Just_Joe

    You want to “cool the Earth”? …then replant all of the trees that have been chopped down… it’ll only take a few centuries (or longer) to “bear fruit”.

  • http://www.librarything.com/profile/Bretzky1 Brett Champion

    As with most problems, the best solution is a combination of solutions. We reduce the amount of greenhouse gases we produce; we reduce the amount of greenhouse gases that are already in the atmosphere; and we do geoengineering to reduce the impact that the existing greenhouse gases have.

    • Joely

      No. This is not a “reasonable people always split the baby” situation. They are MASSIVELY geoengineering right now and the planet is experiencing die-offs of plants, animals, and microorganisms. As we speak the planet is 20 percent darker than it was a decade ago. What these fake news stories are doing is trying to come up with a take that will shut people up as the deleterious effects become so in-your-face that even the “straight clouds in x-formations are natural” set will be asking why they can’t out stop coughing. STOP SUPPORTING YOUR OWN DEMISE!

  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    Already geoengineered!!! Discover magazine never makes a mistake. It says this, and it never makes a mistake.


  • EdDemian

    Humanity has no choice. Geoengineering, baloney, anything we start to do right now is Georemediation and will be for a while, untill we repair the dammage we’ve done so far. We have done this by deforrestation and rampant goat hearding in some parts of the world, but the dammage is not irreversable. There are some signs of hope. China is ahead of the world in reforrestation. That is working fantastically well. Africa is building the Trans-Africa cannal which, when finished, will turn the arrid central African continent into a garden. Russia has started to recharge the Aral Sea to bring it back. The Arabs are planting trees in the desert. Immagine what would happen to the arrid western part of our country, if we diverted just 10% of an Alaskan river that now drains into the Pacific to those areas. Immagine recharging the Ogalalla aquifer, and turnind barren landscape into Carbon scrubbing forrests and world feeding granaries. Half of Californias farmland lies fallow due to lack of water. So we import vegetables from Mexico. As a nation that built the Panama Canal, when others tried and failled, , we seem to have lost our edge.

    • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

      Build anything substantial in America, face a decade of regulatory terror. We have neutered ourselves in deference to imaginary disasters. The AlGore-ithm is Pascal’s Wager. End it.

      • birdpond

        Regulation = protection. Those rules aren’t arbitrary, they arose for good reasons. Like the safety of humans and the planet. Don’t throw the baby out with the bathwater.

    • birdpond

      Yes, deforestation, DEVELOPMENT, the ravenous cattle industry, and wayyyyy too many humans, all trying to outdo the Jones’ as far as ‘standard of living’. Heck, where I live in GA they are bulldozing millions of acres of carbon-sequestering forest and open spaces every year, to put in still more exacerbating roads and commercial development and housing. It’s horrible, like living in a war zone, the things I value and need for my quality of life being forever sacrificed, daily for the almighty $$$. The cute horse farms, living scenic landscapes and biodiverse woodlands are falling like dominoes. And this is in America. If we are unwilling to face our responsibilities, make the tough choices, we are a huge part of the problem. Our unwillingness to change is not due to anything but selfishness and greed. I say we need to lead the world in making positive changes – Not reverse the progress of the previous decades just to appease the oil barons and other industry interests.

      • OWilson

        So you got yours where you live, but you don’t want to give newcomers the same opportunity, right?

        You take the water, electricity, natural gas, cable, roads, telephone, cellular signal, that come to your doorstep, all of which require land from other folks.

        There used to be a word for that NIMBY or something! :)

        “Our unwillingness to change”!

        Are you willing to change?

        Give up your land and move into an aprtment building which is way more efficient? Or is that just for “others” ?

        You sound a lot like Al Gore! :)

        Oil Barons? :)

  • TigerFlame24

    Actually, it’s been going on since 1998. And it is absolutely the cause of global warming.

  • Joely

    This is fake news of the highest order. They’re geoengineering on a massive scale right now and have been for YEARS. To you who are either genuinely this clueless or this much of a mental slave, please let us know where you plan on living when they “successfully” block out the Sun. Oh, and throw in the driving directions to the super-heated place your eternal soul plans to go after a life spent cheering on the demise of Planet Earth. I’ll wait.


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