Climatopolis: How Our Cities Will Thrive in the Hotter Future

Matthew E. Kahn

274 pages, Basic Books, 2010

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As the world begins to confront the mounting challenges of greenhouse gas emissions and global climate change, there are two broad categories of responses. Most frequently advocated are mitigation strategies in which emissions of harmful greenhouse gases are reduced. Less frequently discussed are adaptation strategies, in which people, animals, and plants adapt to changing climatic conditions. It is this latter class, specifically adaptation within cities, that Matthew Kahn describes in his thought-provoking book Climatopolis.

Kahn speculates that competition among cities and individual entrepreneurs will lead to fundamental changes in the structure and functioning of cities. Some cities will be well positioned to naturally reduce the very real risks associated with climate change, and others will be poorly situated. All else equal, the former will thrive and the latter will shrink as people vote with their feet. But it is not simply the natural advantages and disadvantages of cities that will speed or slow their growth. Leadership actions in those cities—some motivated by city leaders and others demanded by their residents—may be even more fundamental in determining how cities fare.

An objective evaluation of this approach can help assess which cities will thrive and which will falter with climate change. But such an evaluation remains speculative, because most human decisions about urban adaptation to climate change have not yet been made. And these decisions will change—positively or negatively—the consequences brought about by climate change.

Kahn is no stranger to speculation, and sure enough, speculation pervades his book. But it is speculation informed by deep understanding of the dynamics of cities and the economic forces that motivate invention, innovation, investment, and change.

Kahn’s book is not utopian. He recognizes that many consequences of climate change remain unknowable. He points out that enlightened institutions are failing to implement adaptations to reduce future climate change risks. One reason is that the consequences of global climate change will evolve slowly enough that many institutions can wait to adapt later. And with profound uncertainty about future patterns of climate change, most people don’t know whether particular adaptations will be desirable. They can analyze; they can speculate; but most cannot be certain that particular changes will be worth the cost. City leaders also underestimate the real risks or have incentives to hide such risks. Climatopolis points at but does not sort out these possible reasons for lack of institutional change.

One of Kahn’s focuses is municipal corruption, particularly in developing countries. Corruption takes resources from cities that could be used to make necessary changes. And corruption reduces adaptation, because decisions by corrupt officials are not generally motivated by best long-term outcomes. Even non-corrupt governments can get in the way of adaptation. Regulation can mask market signals needed to motivate individuals and corporations to reduce overall climate risks. For example, buildings constructed in areas that may flood as the sea level rises should face higher insurance premiums than those constructed on higher ground. Such price variations would give market signals that motivate appropriate adaptation. Yet governments may label such differentiation as price gouging, and blunt price variations. Elected governmental members may be too absorbed with the short-term consequences of their actions to focus on the fate of their cities. Their cities will not adapt prospectively to climate change either.

The subtitle of Kahn’s book is How Our Cities Will Thrive in the Hotter Future. They may in fact thrive. But Climatopolis provides plenty of reasons why many cities will not thrive. And the specific adaptations, although not the general process of innovation and adaptation, are highly speculative—not only in their form but also in their consequences. Appropriately, Kahn provides encouragement for readers to develop their own speculations about how individual cities may flourish or falter with climate change.

Kahn characterizes his book as optimistic. It may be. But one is left with a profound sense of not knowing how severe the consequences of climate change will be for any particular city or region of the world. Adaptation ultimately may be insufficient to solve most problems caused by global climate change. And adaptation is definitely not free; typically it requires many costly investments. Even the best adaptation to global climate change will be very costly to the world’s cities.

A careful read of Climatopolis is an invitation not to rely solely on urban adaptation. As the author argues, adaptation should not be the sole strategy to deal with global climate change. Mitigation is still crucial. Yet the U.S. government continues to shun economic incentives, such as carbon taxes or carbon markets, needed for aggressive mitigation.

My advice: Read the book with an open but critical mind. Reading and reflection should stimulate your own speculations about urban adaptation in the face of climate change. And your mind will be nicely stretched, whatever you ultimately conclude about Kahn’s speculations.

James L. Sweeney a professor of management science and engineering at Stanford University, directs the Precourt Energy Efficiency Center and is a senior fellow of the Hoover Institution, the Stanford Institute for Economic Policy Research, and the Freeman Spogli Institute for International Studies.