These five ideas will either fix global warming or break the planet

April 22, 2015
Small forest fires are pictured between pine trees at night at Sierra de Tejeda nature park, on a burnt mountain from El Collado mountain pass, near the town of Competa

Small forest fires are pictured between pine trees at night at Sierra de Tejeda nature park in southern Spain early June 30, 2014. REUTERS/Jon Nazca

Extreme weather, water shortages and imperiled polar bears: The effects of climate change are obvious and dire. To stem the tide — literally and figuratively — even educated experts are now pitching ideas straight out of science fiction.

On some level, it’s understandable. The grim reality of climate change poses some well-documented problems for humans. The biggest challenge, so far, has been convincing people to do less harm when it comes to the climate. Despite scientists’ plea to cool it with carbon dioxide (CO2) emissions — the most egregious of greenhouse gases contributing to climate change — CO2 levels continue to surge. Today, we put a whopping 20 times as much carbon into the atmosphere as our planet can remove naturally. To get back to healthy levels, we would have to cut our emissions by a staggering 98 percent.

“Could you imagine living on 2 percent of your annual income?” says David Battisti, an atmospheric scientist at the University of Washington. “That’s the problem: People can’t envision how you’d actually get this done.”

That line of thinking has led a cadre of scientists to explore alternative approaches to combating climate change. These approaches, known colloquially as geoengineering, take drastic steps to artificially manipulate the environment to help cool it. The techniques are big and brash; they are also very risky and in no way ready for prime time.

Despite being untested, and their consequences unknown, discussing such strategies has become less taboo of late, thanks, in part, to an increased sense of urgency to find short-term solutions.

These are the five most-discussed ideas in geoengineering to combat climate change:

1.    Fake a volcanic eruption

When particularly explosive volcanoes erupt, they blast ash and sulfuric acid droplets into the atmosphere, which then morph into tiny reflectors that shield Earth from the sun. The result of this natural cycle is a global cooling effect. To mimic this process, scientists have proposed injecting a layer of sulfur dioxide particles into the stratosphere, most likely via aircraft. All things considered, the process is relatively straightforward and affordable. The estimated price tag is measured in the tens of billions of dollars, compared to the coming annual costs of climate change projected to be between $200 billion to $2 trillion annually.

In abundance, however, these particles gradually chip away at the ozone layer, reducing its ability to absorb the sun’s rays and allowing dangerous radiation through. Another problem: Once injected, the particles tend to spread around the globe and linger for years, making the process hard to undo if things go awry.

2.    Make clouds brighter

Clouds keep things cool by reflecting the sun’s rays away from Earth. The whiter the cloud, the better it is at reflecting the sun. By seeding certain clouds with whitening materials — basically tiny particles of saltwater taken from the ocean below — we can transform them into natural sunshields. This cloud-brightening method costs about as much as the fake volcanic eruption option — roughly the amount Facebook paid for WhatsApp. It’s also less risky than injecting particles into the stratosphere because a weather system’s impact is regional, not global.

But lowering temperatures by blocking the sun’s rays is not without problems. Reducing the heat from the sun also means less water from Earth’s surface evaporates back up into clouds. That means when the clouds drift toward other parts of the world as part of a normal weather pattern, areas expecting rain might not get it anymore. The impact could be devastating and experts warn that altering weather patterns could spark water wars.

3.    Fling a giant sunshield into space

You know those accordion-like sunshades made for car windows to keep the interior cool during summer? Scientists have proposed using that same principle to cool Earth. This technique would launch an enormous set of particle-based reflectors into space, positioning them between the sun and Earth to act as a giant parasol.

We know that this technique could cool Earth efficiently and relatively quickly, but the logistics and cost are serious obstacles. One proposal, for example, would launch a 60,000-mile-long shield containing 15 trillion reflective discs, each roughly 2 feet across, nearly a million miles into space. Even if we could pull that off, once the shade is up there, it’s up there for good.

4.    Scrub the air of CO2

The goal here is to separate CO2 molecules from the air by passing it through chemical filters of a sort, which absorb CO2. This technique actually makes a lot of sense if you’re trying to filter carbon dioxide from, say, the smoke stack of a coal plant before it gets released into the atmosphere. If you try grabbing air out of your backyard, however, things get tougher: only about half a percent of that air is CO2. That’s not a great return rate, as you’d have to put a tremendous amount of air through a filtration process to have much of an impact. “The cost of doing this is astronomical,” atmospheric scientist Battisti said. “We’re talking about a good chunk of the U.S. GDP.”

5.    Enrich the ocean with iron

Studies have shown that dumping iron dust into the ocean encourages the growth of blooms of phytoplankton — microscopic drifting plant life — that absorb atmospheric CO2 from the ocean. The hope is that after these tiny ocean plants die, they descend to the seafloor and take the carbon with them. The more phytoplankton, the more carbon they’ll pull down to the bottom, the thinking goes.

The problem is when phytoplankton sinks, other small ocean organisms consume and excrete them. This recirculates the carbon up to the ocean surface and ultimately back into the atmosphere as CO2. Scientists demonstrated that ocean enrichment, which would require depositing hundreds of tons of iron into the sea, would work, but its effect on temperatures and atmospheric levels of CO2 would be minimal, making the risks associated with mucking around with ocean ecosystems not worth taking.

So, yes, some of these ideas are bonkers and could potentially spark environmental issues much more atrocious than the ones we have now. But the fact that some of these are even on the table should be indicative of an even more terrifying reality: We need a solution to climate change, and we need one fast.


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The ocean is widely seen as a bank for carbon storage, settling dead plankton as a key contributor to this. What do you propose as an alternate mechanism for the carbon that accumulates on the ocean floor?

Posted by JonDW | Report as abusive

Every day I wake up I turn on all the lights in the house, open the windows run the heat on high all day long and idle my two clunky V8 in the driveway for at least 5 hours just to anger my climate change conscious neighbors.

Posted by Macedonian | Report as abusive

Macedonian: I doubt your that ambitious.

Posted by brotherkenny4 | Report as abusive

Macedonian: I doubt your that ambitious.

Posted by brotherkenny4 | Report as abusive

Every day I wake up and laugh at my fat neighbor who leaves his trucks running for 5 hours, while he goes back inside with his extra bedroom lights on. I borrow his vehicles. With his wife in the passenger seat.

Posted by AlkalineState | Report as abusive

We need a solution that will cure Julia Calderone and her fellow eco-nazis of their hysterical non-stop panty wetting over a bunch of bogus computer models

Posted by Armigerous | Report as abusive

We could significantly reduce climate warming (which would be useful whether or not the arcane analyses can be considered scientifically proven) by limiting US per capita energy consumption to levels current in the rest of the world.

Posted by captainbwana | Report as abusive

The fastest, cheapest, most effective method of ending global warming?

Easy, stop funding politically motivated bad science with government grants.

Posted by 1776_Minded | Report as abusive

“Climate change” is now a politicized term and this article impertinently suggests that fast action and lots of money is needed right away. As detailed in “The Future We Want,” the outcome document with 283 demands from the Rio+20 summit, the struggle is between some of those who now control many people and their resources against a competing group that also wants to control other people and their resources. They’re two sides of the same coin when the real political divide is between those who want to control and power against those who have no such desire and want to be left alone as long as they’re harming no one.

Every scheme mentioned is ludicrous when planting trees is the way to go along with technical improvements in the development of cleaner energy and more efficient use of energy. This article is disingenuous when we’re at a point where mitigating the effects of greenhouse gases already added to our atmosphere since 1880 (correlated with temperature that has risen 0.85 degree Celsius) is more important and more effective than the elimination of carbon dioxide emissions by 98% — a job for the 22nd Century while we can only do our best with what we know and can use. Small scale nuclear reactors can eliminate fossil fuel use five to ten times faster than solar, wind, and other renewable energy sources and should be seriously considered.

Posted by JimVan | Report as abusive

Hmmm. Wondering why I bothered to sign-up to Reuters when none of my comments get posted. This is my 3rd in the last 6 hours, yet the previous two have not been posted. While others in the same time frame have been.

Posted by 1776_Minded | Report as abusive

You might have more comments, if you actually allowed comments.

Posted by 1776_Minded | Report as abusive

Over the past 2 years I was in pursue of my thought for 100% fumes neutralizing, electrical filters for oil in oil based vehicles. What a machine can do, hey. With theoretic success, as in reasons for optimism.
I also defined other global warming effects leads and solutions.
My blog where I published my ideas is a 15 min. read, the filters are the bottom post.
I try to get my message to the people, so far I failed. Hope this ok here. ; I’m almost prepared.

Posted by dirkgielen | Report as abusive

The translation of every “DO SOMETHING” panic-monger argument is,


‘Clearly, climate change is a crisis. Its a disaster about to happen. When? To whom? What scale? well, that’s hard to say. But its a *crisis* nevertheless. Exactly the kind of crisis that, oh, should cost taxpayers a few billion a year. Why not? Do you want to be one of the ‘do nothings’? I hope not.’

its all a charade, endlessly repeated, to justify throwing money around and imposing regulations that the same anti-capitalist envirosocialists have had on their wishlist since long before “Global Warming” even existed in the public consciousness.

Call me back when they have a new scam to peddle.

Posted by BBERDUDE | Report as abusive

For those who believe that human-produced CO2 is the proximate cause of global warming, the most practical solution is to increase use of nuclear power, which produces no CO2 emissions. Eventually the environmentalists will be faced with a stark choice: Live on 2% of their former income as the article indicates, or come to their senses and embrace nuclear. I’m sure some would choose the 2% option.

Posted by Randy549 | Report as abusive

whether you agree or disagree.. the sad fact is nothing can or will be done about the problem.

there are 7 billion folks out there trying to survive. Soon to be 9 billion. Each will do what is best for them. Drive to work, heat their home, use plastic products, eat food, drink water…

They will survive and contribute to the problem of ocean pollution, water scarcity, burning carbon, etc etc… or they will join the rebel groups that are just starting to show up around the world.. When poverty hits, when resources get scarce, when the middle class collapses – pitchforks will be replaced with AK47’s and we will have Africa/ISIS all over the place…

Posted by michaelryan | Report as abusive

Humans produce less than 4% of carbon dioxide. The rest is produced naturally. CO2 is increasing at 1.3 parts per million per YEAR.
It takes humans 22 years to increase greenhouse gas concentration 1%.
Total greenhouse gas concentration is around 15,500 with water vapor accounting for 15,000 ppmv.
Water vapor is 7 times more potent a greenhouse gas than carbon dioxide.
The Global Warming Scam has not slowed down Barack Obama, Al Gore, United Nations functionaries, researchers, Earth Day extremists, or “scholars.’
All continue to fly and drive far in excess of the little people they try to command and control.

Posted by Illini | Report as abusive

Not to race to conclusions about the importance of the political game here, but you missed the obvious one. Nuclear Winter. That was the bread and butter of fear and nighttime horror stories since much of the time since the 1940’s. And that was always accepted as a fact, that is, that humans can devastatingly change the Earth..

Posted by stephenweber | Report as abusive

What? Really?

Posted by beofaction | Report as abusive