Intentionally messing with the world’s climate sounds like something only a comic book villain would do.
But in March, at an unprecedented conference in northern California, a group of climate scientists and officials from several countries met to discuss how best to go about doing it.
“Geoengineering” is a blanket term used for a growing number of strategies for blunting the ill effects of global warming. Proponents argue it may be needed as a third option. Cutting emissions of greenhouse gases (mitigation) and preparing to live in a world with an altered climate (adaptation) are already much discussed.
Ironically, this emerging field has mostly reluctant proponents, earning geoengineering the title of “a bad idea whose time has come.”
Any attempts to manipulate Earth’s climate would entail many risks. Even those who favor research say many types of geoengineering should only be used in a worst-case scenario, if abrupt and severe climate change demanded a drastic response.
But geoengineering should join the public discussion, even if at first blush many of these ideas sound more like science fiction than solid science.
Some measures involve so-called solar radiation management – slightly dimming the amount of sunlight reaching Earth to create a cooling effect that would cancel out global warming from greenhouse gases. These ideas include shooting reflective particles into the upper atmosphere or creating “microbubbles” in ocean water that would act as giant mirrors to reflect more sunlight back into space.
“Artificial trees” could absorb CO2 just as real trees do and store it underground. Or perhaps real tree species would be genetically altered to be super efficient CO2 suckers.
One idea, seeding the world’s ocean with iron particles to promote the growth of CO2-gobbling algae, has become an early example of how unintended problems could arise. A new study shows that adding iron may favor growth of a type of algae that is toxic to humans.
Some argue that even researching geoengineering is unethical. They say that learning how to employ such measures will only ensure that they will be used someday – without a real understanding of the unintended consequences.
Rogue nations might act on their own. Countries in the developing world are likely to have the least say in what geoengineering techniques are employed, while suffering from any ill effects. Who will decide what geoengineering is done and what isn’t?
Scientists working on geoengineering ideas insist they should only be used hand in hand with cutting greenhouse-gas emissions, not as a substitute. But opponents worry that geoengineering will be seen as a cop-out, a way to continue profligate coal and oil burning, with geoengineering supplying an easy future fix.
Since the entire world would be affected, an international agreement should govern any use of geoengineering.
But just as the summit in Copenhagen, Denmark, showed the difficulty of agreeing on limits to greenhouse-gas emissions, a geoengineering treaty could be a tough sell as well. Countries will have different priorities, wishing for more or less rainfall, more or less warming, more or less willingness to take risks.
Because the effects of geoengineering could be unpredictable and variable, improved conditions in some parts of the world could be accompanied by worse conditions elsewhere.
Short of a true international treaty, a group of leading scientific nations – the United States, Japan, China, India, Russia, Brazil, and European countries – might join to craft an agreement on how to research and how to test geoengineering.
Any research will have to be carefully thought out. It must be conducted with caution, openness, international cooperation, and humility.
Not beginning, though, risks not being ready should a worst-case scenario arise in future decades. It’s better to determine the best ideas and carefully test them, in order to make implementing geoengineering – if that ever becomes necessary – as low-risk as possible.
Yes, the world could be cracking open a Pandora’s box. But in the case of geoengineering, knowledge is better than ignorance.