Photo: Is geoengineering a silver bullet for climate change?

One of our greatest impacts is global warming, fuelled by massive increases in atmospheric carbon dioxide from burning oil, coal and gas. (Credit: Lee Shelly via Flickr)

By David Suzuki with contributions from Ian Hanington, Communications Manager

Altering environments to suit our needs is not new. From clearing land to building dams, we've done it throughout history. When our technologies and populations were limited, our actions affected small areas — though with some cascading effects on interconnected ecosystems.

We've now entered an era in which humans are a geological force. According to the website Welcome to the Anthropocene, "There are now so many of us, using so many resources, that we're disrupting the grand cycles of biology, chemistry and geology by which elements like carbon and nitrogen circulate between land, sea and atmosphere. We're changing the way water moves around the globe as never before. Almost all the planet's ecosystems bear the marks of our presence."

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One of our greatest impacts is global warming, fuelled by massive increases in atmospheric carbon dioxide from burning oil, coal and gas. Thanks in part to self-preserving industrialists, complicit governments and deluded deniers, we've failed to take meaningful action to address the problem, even though we've known about it for decades. Many now argue the best way to protect humanity from the worst effects is to further alter Earth's natural systems through geoengineering.

Geoengineering to combat climate change is largely untested. Because we've stalled so long on reducing carbon emissions and still aren't doing enough, we may have to consider it. What will that mean?

As it relates to climate change, geoengineering falls into two categories: solar radiation management and carbon dioxide removal. The former involves reflecting solar radiation back into space. The latter is aimed at removing carbon dioxide from the atmosphere and storing it.

Solar radiation management includes schemes such as releasing sulphur aerosols into the atmosphere to scatter sunlight and reduce radiation, creating or whitening clouds by spraying seawater or other materials into the air, and even installing giant reflectors in space. These methods don't affect CO2 levels and so don't address issues like ocean acidification, but they offer possible quick fixes to reduce warming.

An example of carbon removal is fertilizing oceans with iron. Iron stimulates growth of small algae called phytoplankton, which remove carbon dioxide from the sea and release oxygen through photosynthesis. This allows the oceans to absorb additional CO2 from the atmosphere. When the plankton die and sink to the ocean floor, they become buried under other materials, storing the carbon within them.

The Alberta and federal governments have spent billions on their favoured carbon-reduction method, carbon capture and storage — trapping CO2 released by burning fossil fuels and pumping it into the ground — but this method has yet to be perfected.

Many schemes are controversial and have shown mixed results in tests, and the danger of unintended consequences is real, including further catastrophic, irreversible damage to the climate system.

One major drawback with geoengineering is the mistaken idea that it can be a substitute for reducing greenhouse gas emissions that cause climate change. That many geoengineering projects are fraught with danger and would not resolve the problem quickly enough or even effectively — and would do little or nothing to resolve other fossil fuel problems such as pollution — makes this a critical concern.

There's also the matter of who would decide what methods to apply and when and where. The issue of "rogue" geoengineering has also cropped up in my part of the world, when an American businessman working with the Haida village of Old Massett dumped 100 tonnes of iron sulphate into the ocean in 2012 for a salmon restoration and carbon-reduction project.

A U.K. Royal Society study concludes that geoengineering "should only be considered as part of a wider package of options for addressing climate change" and carbon dioxide reduction methods should be preferred over more unpredictable solar radiation management.

Scientists at the Berlin Social Science Research Centre suggest creating "a new international climate engineering agency to coordinate countries' efforts and manage research funding." Because some geoengineering is likely unavoidable, that's a good idea. But rather than rationalizing our continued use of fossil fuels in the false belief that technology will enable us to carry on with our destructive ways, we really need governments, scientists and industry to start taking climate change and greenhouse gas emissions seriously. We can't just engineer our way out of the problem.

August 22, 2013

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May 29, 2014
9:19 PM

Hemp grows 16 ft tall in 100 days and uses massive amounts of Co2. We need hemp to become the largest industry as it was prior to the oil age.

Feb 18, 2014
10:38 AM

We do believe in chemtrails as the crisscrossing above southern Michigan and Ontario are not regular flights! open your eyes and see the situation for what it is also there are other explanations and do not care for the input of people that have their nose right in it and make fun of the general public as if we are retards or simple minded. We are constantly being sprayed world wide now and the pictures speak for themselves with close ups.

Nov 22, 2013
6:11 PM

I’m confused when you appear to deny chemtrails but yet you admit that they are spraying. We are being sprayed here in British Columbia on a regular basis. We can’t have a sunny day without looking up to see the spraying and then haze for days. What is it and why the big secret to the public. If the global warming is so bad then why don’t governments just stop all the main contributors to the problem such as fracking. I personally could deal with being cut back on energy consumption vs being sprayed by an unknown entity and worried sick about what’s happening to the ecosystem.

Sep 06, 2013
11:09 AM

We already have the technology to remove large amounts of atmospheric CO2 while providing food, fuel, fibre, and medicine, saving forests, and ending fossil fuel use. The answer is hemp.

Aug 28, 2013
3:31 PM

@Vicki We could feed the bugs to even tastier critters like fish!

Organic permaculture, forest gardens etc seem to be working in some places. It’s a whole different way of farming and can be much more productive than what we have seen in the past. Most of these techniques use no chemicals at all but do require more labor input. More labor is a good thing when there are plenty of unemployed or underemployed people out there.

Aug 24, 2013
11:29 PM

What would the impact on climate change be of transitioning the food supply from large-scale mechanical agrichemiculture to organic permaculture and neighborhood-scale farming? Or adopting plant- and bug-protein in lieu of a livestock-based diet? I can clearly see how bugs would make a much tastier protein base for fast food than the heavily treated and processed “meat” people kill themselves on now, and it would likely be more wholesome and less toxic. And with less livestock to feed, less menhaden are overfished, allowing them the freedom of the ocean to eat away toxic algae blooms and be the keystone base prey of the Atlantic food web.

Aug 22, 2013
2:39 PM

What does it mean for us when we start re-engineering the environment we evolved within?

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