Book Review: Drought: An Interdisciplinary Perspective
Cook, Benjamin I. Drought: An Interdisciplinary Perspective. New York: Columbia University Press, 2019. 215 pp. ISBN (paperback): 9–780231– 176897.
By Adam Sweeting, Boston University
The title of Benjamin I. Cook’s Drought: An Interdisciplinary Perspective succinctly states the author’s intention to pre- sent a wide–ranging discussion of the multiple factors that contribute to the extended dry conditions that periodically and sometimes quite dangerously visit the landscape. Unlike a devastating hurricane, droughts, writes Cook, are “slow mov- ing disasters, with effects that accumulate increasingly over weeks, months, and even years as moisture deficits propagate through ecosystems and the hydraulic cycle” (vii). They are also complex systems that sit “at the intersection of climatology, meteorology, hydrology, ecology, agronomy, and even economics.” For Cook, a research scientist at the NASA Goddard Institute for Space Studies, the “fundamentally interdisciplinary nature of drought” poses a challenge to anyone seeking to comprehend fully the impacts and dynamics of such events (viii). The structure of Cook’s book speaks to this challenge, with separate chapters on the various aspects of drought. Such an approach might better be described as multidisciplinary rather than interdisciplinary, since the chapters do not truly come together as a synthetic whole. To be sure, Cook expertly describes the mechanics of drought in clear, user–friendly prose that enables non– specialist readers to come away with a firm understanding of how and why droughts originate. More attention to the social and cultural aspects concerning the human experience of drought, however, would help to deliver on the interdisciplinary promise of the book’s title.
The early chapters cover the basics of how water, the essential ingredient for life, functions within various Earth systems. Chapter 1 traces the hydrological cycle by which water travels by the processes of precipitation, evapotranspiration, and run–off through Earth’s reservoirs (i.e., oceans, clouds, lakes, streams, aquifers). Chapter 2 covers the normal interaction of the water cycle and the global climate system, while Chapter 3 narrows the focus to consider the specific factors in the climate system that give rise to drought. These descriptions are accompanied by informative illustrations, though the small fonts used in the explanatory texts can make them initially hard to decipher. Non–specialist readers seeking a basic understanding of drought will want to pore over these chapters carefully. And, for places where the non– specialist might need assistance understanding the occasional technical or specific scientific term, Cook provides a helpful and thorough glossary.
In the early chapters, Cook also describes the different types of drought (meteorological, hydrological, and agricultural). We learn, too, that not all droughts are the same, and that we must pay particular attention to geographic specifics if we hope to understand them: “A drought in New York, relatively speaking, will still be wetter in terms of absolute values than a normal year in Arizona” (41). Vagaries in the climate system, too, can produce “snow droughts” with devastating im- pacts on historical spring run–off patterns, or “flash droughts” that occur with “little to no advance warning” and can lead to unanticipated agricultural losses (65).
Readers interested in how anthropogenic climate change will affect the frequency and extent of drought will want to ex- amine closely the middle chapters in which Cook takes up the climatological conditions of the early Holocene and the likely impact of rising temperatures on the future hydroclimate. Through the use of paleoclimate proxies such as tree rings and lake sediments, we know that a warm and wet period during the mid–to–late Holocene (~9,000 to 2,000 years ago) gave rise to the so–called Green Sahara. A lush landscape vastly different from the Sahara we know today, the Green Sahara was produced by naturally occurring processes related to slight shifts in Earth’s orbit; subsequent natural changes, in turn, pushed back the green and opened the way for sand. As Cook demonstrates, periods of relative dry- ness and moisture have always occurred. But now, anthropogenic climate change has thrown multiple monkey wrench- es into the natural workings of Earth’s systems. The likely result, Cook shows, will be deeper and more prolonged
droughts, such as the ones that recently descended on California and Syria. Cook describes the technical aspects of these disasters clearly and with great skill. But as with other aspects of the book, the human experience of drought goes missing. What fears, anxieties, or trepidations did they inspire? How might scholars from the social sciences or the humanities respond to them? Where are the poems or novels of drought? One is reminded in this context of John Stein- beck’s depiction of Dust Bowl refugees in the opening chapters of The Grapes of Wrath. A less technical and more fully interdisciplinary discussion would add depth to these otherwise fine explications.
The book’s full promise most closely comes to fruition in Chapter 6, where Cook presents case studies of the 1930s Dust Bowl in America’s central plains and the Sahel drought in West Africa, which lasted from the late 1960s to the early 1990s. Here, we encounter how human land use practices and population trends contributed to soil erosion and degraded land. When these practices intersected with global climate patterns, they amplified the effect of long– term droughts; what began as naturally occurring meteorological events turned into agricultural and economic disasters. Although we do not quite get the sense of the human toll caused by these events, Cook presents them as emerging, at least in part, from human action. Droughts have always occurred and will continue to occur even if humans no longer walked the Earth. But we are here, and our actions are almost certainly making drought conditions worse, with profound implications for ecological and human health. As the climate warms, some parts of the world will see more rain, but others – the American southwest and sub–Saharan Africa, for example – will see much less. The depth and extent of drought will intensify. As we look toward a future defined by anthropogenic climate change, Cook’s case studies offer a timely remind- er of how our land use practices coupled with excessive greenhouse gas emissions will exacerbate dangerous conditions. There will be more of the “slow moving disasters” he describes in the Preface.
In the final two chapters Cook examines land degradation and the tapping of groundwater to support large–scale agriculture, two processes connected with drought that can be made worse by human action. Land degradation, defined here as the “sustained, sometimes irreversible, loss of ecological productivity and ecosystem services” results from soil erosion and compacting through poor soil management and overgrazing (143). How nations and communities manage their soil will emerge as one of the great agricultural challenges in the wake of climate change. So, too, will the way they man- age groundwater in a period when we know drought will intensify. As Cook writes at the close of the final chapter, “water will remain a critical and challenging resource to manage in most regions of the world” (180). The quality of life for the human and non–human will be determined by how we confront the conditions we have created. Water management will indeed be a major resource challenge, and Drought: An Interdisciplinary Perspective does an excellent job of showing why. But how we manage water in our droughty future will also be a spiritual challenge that will test our commitment to environmental justice and the hope that our everyday aesthetic and imaginative encounters with water – the sustainer of life – will not run dry. It is these overtly anthropocentric aspects that go missing in Cook’s otherwise excellent account of the meteorological and hydrological systems that give rise to drought.