Under a White Sky: The Nature of the Future (2021) is a nonfiction book by the Pulitzer-Prize winning American author Elizabeth Kolbert, who is also a staff writer at The New Yorker. In three sections, the book chronicles how humanity has altered the planet’s landscapes, biodiversity, and atmosphere for the worse. It also details how attempts to mitigate the impacts of those alterations are themselves fraught with potential pitfalls. Upon release, the book was shortlisted for the Wainwright Prize for Writing and named one of the best books of the year by Esquire and Publisher’s Weekly, and became a national bestseller.

Summary

The book’s first section opens with a meditation on the metaphoric potential of rivers, which authors ranging from Mark Twain to Heraclitus have used to represent hidden meanings, destiny, and change.

Kolbert then describes the modification of the Chicago River, which underwent a major change in the late 19th and early 20th centuries, with the construction of the Chicago Sanitary and Ship Canal. The Canal reversed the flow of the river so that waste from the city of Chicago would flow not into Lake Michigan—its drinking water supply—but in the opposite direction, toward the Mississippi River and ultimately, the Gulf of Mexico: “a textbook example of what used to be called, without irony, the control of nature” (5).

Nature quickly proved uncontrollable: While the project addressed the immediate issue of waste, it created an unforeseen problem in the form of Asian carp. Introduced to the US to prevent the spread of an invasive plant, the fish quickly escaped from their original release point and spread up the Mississippi. Because the Sanitary and Ship Canal linked the Mississippi and the Chicago rivers, the carp now threaten that ecosystem and the Great Lakes. Projects to prevent carp from reaching the Great Lakes include everything from sending electric currents through the river, to hosting fishing tournaments and other events aimed at encouraging people to see carp as a viable food source. Ultimately, such measures may not come close to addressing the scale of the problem and may have unintended consequences of their own.

In subsequent chapters in this section, Kolbert explores how the modification of the Mississippi River is creating rapid land loss and erosion in Louisiana. While controlling the Mississippi with levees reduced flooding, it deprived the area of the essential sediment replenishment that the river provides. As a result, land is disappearing in places like Plaquemines Parish, which is already below sea level. To address this, officials have implemented artificial means to restore sediment, but this will only protect selective parts of the coastline, even as other parts continue to disappear. The extent of the measures on the Mississippi has made it neither a natural nor a manmade system, but something in between.

The book’s second section describes attempts to manage biodiversity. The Devil’s Hole pupfish is a rare species that only lives in one Nevada pond, where they were likely deposited in the distant past when what is now desert landscape was wetter. In the 20th century, the aquifer that feeds the pond was partially drained by an entrepreneur who wanted to grow alfalfa in the desert. In response, scientists removed several dozen pupfish to create a backup population in an artificial reconstruction of the pond roughly a mile away, while installing an artificial shelf and in the real pond to provide breeding habitat. Such interventions make the pupfish a species pushed to the brink by humanity, and now dependent on humanity for their survival. Other species that fit the category include corals, which provide habitat for an astonishing proportion of all marine life, but are under threat from rising water temperatures and ocean acidification. In order to preserve some corals, researchers are trying to develop corals that are more likely to withstand the ocean conditions under climate change, but such measures are piecemeal, slow, and unlikely to replicate the long process of evolution that has produced coral reefs, some of the most biodiverse environments on the planet.

The final section dives into humanity’s alteration of the atmosphere through the burning of fossil fuels, and the various technologies and techniques that could reverse its ill effects, intervention that is urgently necessary. Carbon capture draws carbon dioxide out of the atmosphere and stores it underground, in trees, or in vegetation at bottom of the ocean. The International Panel on Climate Change models show that keeping global temperature rise below 1.5 degrees Celsius involves carbon capture. Though carbon capture is not complicated and already commonplace on submarines, where carbon dioxide is removed from the air to keep crew safe, the challenge is scale and cost. No current technology comes close to removing the forty billion tons of carbon dioxide currently being released into the atmosphere every year. Solar geoengineering proposes to seed the stratosphere with particles of diamonds or calcium carbonate to prevent the sun’s rays from reaching the earth, slow the increase in temperature. However, once this technology is deployed, it cannot be halted so long as humanity continues to release carbon dioxide. Negative emissions technologies face a similar problem: Offsetting some of the effects of climate change saps some of the urgency from transitioning off fossil fuels.

Ultimately, humanity may not have a choice, as these technologies, fraught with unintended consequences as they may be, could offer the only way to avoid even worse outcomes that are the result of past human decisions. Human attempts to control nature have brought about a future that’s likely to be different from any period in the planet’s history.