Will geoengineering save agriculture from climate change? by Usbek et Rica


The techniques of climate manipulation are experiencing a boom, as it becomes more and more likely that we will one day have to resort to them to fight climate change. In this context, what can we foresee the future of agriculture to be?


Geoengineering has had the wind in its sails for a few years now, in the light of growing concern over climate change. It proposes a radical, efficient and fast solution to global warming, which could prevent the Arctic from melting and food productivity from dropping over the coming decades. Geoengineering is the act of deliberately modifying the climate in order to fight global warming. Two main approaches exist: solar radiation management (SRM), which aims to divert some of the heat that comes from the sun by injecting sulphur dioxide into the stratosphere; and carbon dioxide removal (CDR), which intends to sequestrate enormous amounts of carbon and stock them in the ground or at the bottom of the oceans. Either method would make it possible to dramatically and rapidly reduce the warming of the planet, but scientists working on such high-tech projects all present them as “last resort solutions”, to be used only if we fail to limit our greenhouse gases emissions sufficiently. In fact, their consequences on the fragile balance of our ecosystem are hard to predict, and therefore frightening. And the idea of tackling the symptoms rather than the cause is not highly desirable or exciting either.

But we may soon have no choice.

In order to stabilize the climate now, we’d have to go to zero emissions almost immediately – something nobody thinks is even remotely possible,

wrote Chris Mooney from Wired, three years ago. Which is why geoengineering is starting to be considered by several scientists (such as Nobel Prizewinner Paul Crutzen, or the members of the Intergovernmental Panel on Climate Change, who addressed the issue in a workshop in 2011), as a serious plan B that, even if it is not desirable, must nonetheless be contemplated. Taking action could well mean starting to play God with the climate, sooner than we may think. And the implications for agriculture are inevitably key: how do climate disorders affect it? What would geoengineering do to food productivity, given that we know that SRM geoengineering has effects on precipitation? Who would manage it, to what extent and at what risks?


The inequalities of climate change

Global warming does of course have effects on water and on climate, which are crucial to agriculture. But it actually does not affect everyone in the same way – it perpetuates and even worsens inequalities that already exist. In the regions that get warmer and moister, as in the northern hemisphere, yields are likely to increase by 2020, as estimated by the NGO Universal Ecological Fund (FEU-US). On the contrary, areas that get dryer will see their yields drop, and their arable lands shrink. This concerns mainly southern-hemisphere countries, of course. By 2025, Africa could have lost two thirds of its arable lands to drought. The risks of food shortage are thus growing: according to FEU-US, the world production of wheat could reach a deficit of 14% compared to demand within the next ten years. Rice’s deficit would be 11%, and corn’s 9%. And this shortage is unlikely to affect the richest countries in the first instance (they have climate, among other things, on their side). Ken Caldeira, an atmospheric scientist who researches intentional climate modification at the Carnegie Institution for Science at Stanford University, shares this view. His most recent works with Julia Pongratz have established that crop yields would benefit from geoengineered agriculture… and this is why he believes that SRM techniques might be pursued by southern-hemisphere countries precisely to that end. “Many crops that grow in the tropics are expected to be heat-stressed”, which maylead to “widespread famines in the tropics”, he explained toEnvironmental Research Web.

I think it might be the leaders of those tropical countries who might have the greatest motivation to develop these [geoengineering] systems.

In other terms, “poor people in the tropics who are trying to defend themselves from the legacy of industrial CO2 emissions from the North” would be cornered into having to do something that no one really wishes to do: starting to manipulate the climate to avoid droughts or floods, and to ensure better conditions (notably soil moisture) for their crops.

Who gets to decide?

This brings up a crucial question: if we are ever forced to adopt geoengineering systems, who will get to decide who does what? Geoengineering cannot have a local impact: each and every initiative will have world-wide and systemic effects. And there is a considerable risk of desperate countries and governments, in the aftermath of a climatic catastrophe or to combat food shortage, taking the unilateral initiative of implementing such technologies, without international consultation, and without knowledge of the side effects. What if one single actor decides to « fertilize the oceans with iron in order to sequester carbon dioxide; launch fleets of ships to whip up sea spray and enhance the solar reflectivity of marine stratocumulus clouds; use trillions of tiny spacecraft to form a sunshade a million miles from Earth in perfect solar orbit », in the words of Wired? American futurologist Jamais Cascio fears that it would result in conflicts. In the latest issue of Usbek & Rica, he says:

I have once participated in a simulation exercise about a climatic disaster that would push China to deploy geoengineering unilaterally. This scenario led to a high risk of war with the United States.

He therefore advocates international supervision of geoengineering, to be carried out by the United Nations or the World Health Organization. And what if private companies decide to take the lead on the development of SRM geoengineering? After all, Bill Gates is today the biggest investor in this field, with at least $400 million invested in projects and patents so far. Richard Branson, chairman of the Virgin Group, also strongly supports research, having declared a few years ago: “If we could come up with a geoengineering answer to this problem [of climate change], then Copenhagen [climate conferences] wouldn’t be necessary. We could carry on flying our planes and driving our cars.” For other (less carefree) reasons, typically yield and productivity, the food industry could also want to move forward with the technology.In any case, without a favourable legal framework, private initiatives will not change our climate by themselves. But the question needn’t be shrugged off, for the technologies are soon going to be available – and there are people who are going to want and need to use them. Transparency and consultation between states on this matter should be established as an imperative, and the need to create an ad hoc organization is getting more and more urgent by the minute.

Yet this scenario must not steal the thunder from a far more important and desirable priority: finding a way to meet the Millennium Development Goal in terms of carbon emissions. The possibility of geoengineering must not keep us from dramatically reducing those emissions. Actually, it may force us to make more and more effort, as no one really wants to come to that final option. As Caldeira says about the study he led with Pongratz,

many people argue that we need to prevent climate change. Others argue that we need to keep emitting greenhouse gases. Geoengineering schemes have been proposed as a cheap fix that could let us have our cake and eat it, too. But geoengineering schemes are not well understood. Our study shows that planet-sized geoengineering means planet-sized risks.

For the two scientists, and many more with them, carbon reduction is definitely a safer bet for countering climate change. The efforts of governments, NGOs, companies and citizens are more important than ever – who knows, they might just keep us from having to resort to geoengineering after all.

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