A Case for Climate Engineering

Preface

It is possible to cool the planet by injecting reflective particles of sulfuric acid into the upper atmosphere where they would scatter a tiny fraction of incoming sunlight back to space, creating a thin sunshade for the ground beneath.To say that it’s “possible ” understates the case: it is cheap and technically easy.The specialized aircraft and dispersal systems required to get started could be deployed in a few years for the price of a Hollywood blockbuster. I don’t advocate such a quick-and-dirty start to climate engineering, nor do I expect any such sudden action , but the underlying science is sound and the technological developments are real.This single technology could increase the productivity of ecosystems across the PREFACE a case for climate engineering  planet and stop global warming; it could increase crop yields, particularly those in the hottest and poorest parts of the world. It is hyperbolic but not inaccurate to call it a cheap tool that could green the world. Solar geoengineering is a set of emerging technologies to manipulate the climate. These technologies could partially counteract climate change caused by the gradual accumulation of carbon dioxide. Deliberately adding one pollutant to temporarily counter another is a brutally ugly technical fix, yet that is the essence of the suggestion that sulfur be injected into the stratosphere to limit the damage caused by the carbon we’ve pumped into the air. Solar geoengineering is an extraordinarily powerful tool. But it is also dangerous. It entails novel environmental risks. And, like climate change itself, its effects are unequal, so even if it makes many farmers better off, others will be worse off. It is so cheap that almost any nation could afford to alter the earth’s climate , a fact that may accelerate the shifting balance of global power, raising security concerns that could, in david keith  the worst case, lead to war. If misused, geoengineering could drive extraordinarily rapid climate change, imperiling global food supply. In the long run, stable control of geoengineering may require new forms of global governance and may prove as disruptive to the political order of the 21st century as nuclear weapons were for the 20th. Many people feel a visceral sense of repugnance on first hearing about geoengineering. For some, the repugnance crystallizes into moral outrage against the very idea that the topic is being discussed; for others, exposure to debate about geoengineering brings with it an appreciation of the hard choices at its roots and an understanding that there are credible arguments for and against. That intuitive revulsion strikes me as healthy; our gadget-obsessed culture is all too easily drawn to a shiny new tech fix. A narrow focus on a technology’s power too easily blinds us to its risks. It’s tempting to wish climate change away by denying the science or by asserting that a quick shift a case for climate engineering  to new clean energy sources provides an easy way out. But there is no magic bullet. We cannot make sound decisions by supposing the world is as we wish it were: the science of climate risk is solid, and the inertia of the carbon cycle combined with that of the world’s economy mean that efforts to cut emissions can only moderate (but not reverse) climate change over this century. As with the capacity to engineer our own genome, humanity is rapidly developing the capacity to engineer the planetary environment. Geoengineering’s powerful potential demands a broad debate that must include not only credible arguments for and against such an intervention, but also, as with genetic engineering , an appreciation of the large questions it raises about nature and technology on a planetary scale. I myself have concluded that it makes sense to move with deliberate haste towards deployment of geoengineering. You may well reach a different conclusion . My goal is simply to convince you that it’s a hard choice. david keith  * * * In this book I attempt a synoptic view of solar geoengineering for the educated non-specialist who is willing to work their way through some complex arguments. I am not a disinterested bystander. Every author’s story is shaped by their biases.The remainder of this preface discloses some of mine. Wilderness has shaped my life. From weekend canoe trips to long solo ski expeditions in the...