Summary: Up in the Air: Part 3 and Afterword

Elizabeth Kolbert opens Part 3, Chapter 1 by describing an email offering to “scrub subscribers’ carbon emissions from the air.” This company, Climeworks, will inject the carbon dioxide (CO₂) half a mile below ground, “where the gas would harden into rock.” Kolbert subscribes to the service and after a year decides to visit the operation in a lava field in southern Iceland. It is located in a geothermal plant—one that relies on steam from underground—called the Hellisheiði Power Station owned by Reykjavik Energy.

She is met there by Edda Aradóttir, a managing director at the energy company. While a relatively clean form of energy, geothermal energy does produce unwanted gases that contribute to global climate change, including CO₂. So Reykjavik Energy uses a machine to capture its CO₂, dissolves the gas in water, and injects it back underground. Calculations by Aradóttir, among others, suggest that the dissolved gas will then react with volcanic rock and mineralize. Aradóttir displays proof that her calculations work: a rock core that is shot through with small holes filled with calcium carbonate representing captured CO₂ emissions.

Kolbert pivots to the topic of when people began altering the atmosphere. One theory traces the process to 8,000 or 9,000 years ago, when farmers first domesticated wheat in the Middle East and rice in Asia. The fields they cleared through burning released CO₂ into the air. A more widely held view traces the start to the late 18th century and the invention of the steam engine, when CO₂ emissions began to rise at a dizzying pace.

Humans now emit nearly 40 billion tons annually. One-third of the molecules of the gas in the atmosphere were created by humans. As a result, average global temperatures have risen by 2 degrees Fahrenheit. Kolbert lists the effects: deeper droughts, fiercer storms, deadlier heat waves, more intense wildfires, rising sea levels, melting Antarctic ice. Entire small nations will be uninhabitable. The “threshold of catastrophe” is an average global temperature rise of 3.6 degrees Fahrenheit. To stay under this threshold, global emissions would need “to fall nearly to zero within the next several decades.” This would require changing agricultural systems, manufacturing, and reliance on gas and diesel for power “and replacing most of the world’s power plants.”

Removing CO₂ from the atmosphere could, however, stave off disaster. The concept, called negative emissions, was developed by physicist Klaus Lackner in the 1990s. Kolbert visits the Center for Negative Carbon Emissions, which Lackner founded at Arizona State University in 2014, together with the scientist. A project in development is a powder that can absorb CO₂ when dry and release it when wet. A machine “the size of a semi-trailer” could use the process to remove a ton of CO₂ every day. It would take 100 million such units to keep up with current global emissions, but Lackner thinks this is possible. He believes humans need to change their thinking about CO₂ and consider it to be like sewage—a problem to be solved rather than one that needs to be eliminated.

Kolbert points out that once CO₂ is in the air, it remains. Cutting emissions is not the solution because even if the world cut emissions in half, the levels wouldn’t drop. They would merely rise more slowly. Nor could emissions be cut in an equal way. The United States has 4% of the world’s population but creates nearly 30% of emissions. In contrast, India will soon be the world’s most populous nation but creates only 3% of emissions. These inequalities have led international climate agreements such as the Paris Climate Agreement, adopted by nearly every nation in 2015, to consider the impact of cutting emissions on developing countries.

Returning to the topic of Climeworks, Kolbert discusses its founders, one of whom—Jan Wurzbacher—she interviews at the company’s headquarters in Zurich. He points out some of the downsides of capturing CO₂ from the air. First, it requires energy, which, if it comes from burning fossil fuels, will only create more carbon. Second, storage sites such as the volcanic rock in Iceland aren’t common. Third, the process is expensive. Wurzberger isn’t sure the world is ready to pay for it.

There are other ways to remove CO₂ from the air. “Enhanced weathering” would spread crushed stone over croplands to react with the gas and draw it from the air. A mineral found in volcanic rock could be dissolved in the oceans, letting the seas absorb more CO₂. Planting a trillion trees would remove as much as hundreds of billions of tons of carbon from the atmosphere. A process called BECCS (“bioenergy with carbon capture and storage”) would burn the planted trees to produce power while capturing the emitted CO₂ and burying it underground. A BECCS pilot program was launched in 2019. Problems of scale and expense exist with all these methods.

In Part 3, Chapter 2, Kolbert discusses volcanic eruptions, beginning with an explanation of the Volcanic Explosivity Index. The index uses exponential increases in quantity, such that a magnitude 4 produces over 100 million cubic meters of ejected material and a magnitude 5 produces over a billion. The eruption of Mount Tambora in Indonesia in 1815 was a magnitude 7 that killed thousands and changed Europe’s weather to “gray and cold.” Harvests failed across Europe, causing mass starvation.

Kolbert interviews Frank Keutsch, a chemist. Keutsch explains that volcanos put sulfur dioxide into the stratosphere. With exposure to oxygen, this turns to sulfuric acid, and its particles remain in the stratosphere to cause lower temperatures. His project for Harvard’s Solar Geoengineering Research Program focuses on “solar radiation management.” It speculates that people can learn to cool the world just as volcanoes do in nature, by throwing reflective particles into the air. Keutsch believes the best particle to use is tiny diamonds because they do not absorb energy. But the diamonds would eventually fall back to earth, an idea Keutsch doesn’t like, as the particles could be inhaled. Calcium carbonate, common in rocks, is another possible substance. A different option is to spray sulfur dioxide into the air, but this could damage the ozone layer.

Next Kolbert speaks with David Keith, a physics professor at Harvard. A strong supporter of geoengineering, he founded the Solar Geoengineering Research Program in 2017. He believes the world can achieve significant cuts in carbon emissions and that carbon-removal techniques will eventually be able to handle the rest of the emissions. He worries, however, about the damage that will be done until this point is reached. His proposal is to try to cut warming in half through geoengineering. The director of Harvard’s Center for the Environment, Dan Schrag, also believes that engineering efforts may be the best chance for saving Earth’s ecosystems.

The author discusses the ease with which geoengineering could be done. A plane called a Stratospheric Aerosol Injection Lifter (SAIL) would carry about 20 tons of particles at an altitude of about 60,000 feet. Cooling would begin immediately, but the process has its own downsides. It only masks warming; if the project stops, the temperature would rise dramatically. More particles—or sulfur dioxide—would have to be injected each year. The more particles delivered, the “greater the chance of weird side effects.” As one example, the sky’s appearance would change from blue to white. Rainfall patterns could be disrupted, and solar electricity would dwindle.

David Keith and Frank Keutsch are collaborating on a test to send a small quantity of reflective particles into somewhere treeless at a 12-mile altitude. The test will not have the effects of geoengineering but will show how the concept might work.

Part 3, Chapter 3 begins with a discussion of the US Navy’s Project Iceworm, which involved building a base called Camp Century in Greenland in 1959. The base was to be the launching spot for rail lines that could shuttle nuclear missiles in the direction of the Soviet Union to intimidate the enemy country. The base was threatened, however, by ice that melted and caused the tunnels to contract. By 1967, the base had been abandoned, but the drilling done there in Greenland’s ice sheet yielded important information about the history of the climate.

Kolbert considers this information as she travels to Greenland, a Danish territory, to visit the Danish-led North Greenland Ice Core Project (North GRIP). The project drills out ice cylinders at a depth of nearly 10,000 feet in Greenland’s ice sheet, which is made of layers of snow. The snow has accumulated in a way that the drilling descends “backward in time.” For instance, at a depth of 140 feet, the snow dates from the American Civil War. At a depth of 5,350 feet, the snow was laid down in prehistory. The team pulls up a cylinder that was made up of snow that fell over 105,000 years ago, as the last ice age was beginning.

The cylinders provide clues to climate history. During the last ice age, called the Wisconsin, the climate of Greenland was variable, with swings of as much as 14 to 15 degrees Fahrenheit. Climate records in other places around the world also showed extreme temperature swings, known as Dansgaard-Oeschger (D-O) events.

The last 10,000 years, however, have had a stable climate. Scientists hypothesize that the temperature swings might be related to “a loss of sea ice in the Arctic.” Given the present loss of Arctic sea ice due to global warming, this is problematic. As the temperatures on the ice sheet have risen by over 5 degrees Fahrenheit since 1990, Greenland has gone from losing 30 billion tons of ice a year to over 250 billion tons a year. The rate compares to the D-O events recorded in the island’s ice cores. At some point, Greenland’s entire ice sheet might disintegrate.

Sea levels have varied widely in the past, like temperatures. At the end of the Wisconsin ice age, there were times when they rose a foot every 10 years. Today they are rising again, threatening coastal cities. One proposal to combat seal-level rise is by blocking the mouth of a large glacier in Greenland.

Kolbert brings the book to a close by describing it as being about “people trying to solve problems created by people trying to solve problems.” She says that all the scientists and engineers to whom she spoke were enthusiastic about their work but that “this enthusiasm was tempered by doubt.” She describes their attitude as one of “techno-fatalism.” The scientists and engineers know they can’t improve on nature. All they can do is offer their best ideas. In this context, the ideas must be considered, however far-fetched a concept such as gene drives or geoengineering might be. Furthermore, they are only presenting the concepts; it is up to future governments to implement them. She ends by imagining a world that has launched “a fleet of SAILs,” the planes carrying particles to be injected into the sky. If despite the launching of particles, global emissions continue to rise, the result would be a never-before-seen climate where “silver carp glisten under a white sky.”

In her afterword, Kolbert says that books about the environment tend to end with “the additional three pages” describing why there is reason to be optimistic. She can’t do so, however, in part because of COVID. The virus could have been contained when the first cases were reported at the end of 2019, but “politics intervened.” Chinese authorities tried to hush up reports of the virus. As a result, a month after the first cases, COVID was present in two dozen countries.

The response to the virus was similar to the ones Kolbert has described in Under a White Sky to combat human-made threats to the environment. The answer was a “bio-technofix,” a rush to develop a vaccine. While the vaccines were indeed created, COVID remains endemic, likely to continue circulating.

She concludes by saying that there are things individuals can do to combat climate change, from riding bikes to taking political action. However, she wants to be honest about “the scale of the challenge.” Once processes of global action have been set in motion, it is extremely hard to stop them. Ultimately, it is the choices people make now that will determine the future of life on Earth. There’s no avoiding this fact because “this marvelous, fragile planet is all we’ve got.”

Analysis: Up in the Air: Part 3 and Afterword

The scientists who work at solutions to carbon emissions in the atmosphere share the belief that cutting carbon emissions is not the answer to the looming crisis. Kolbert agrees, pointing out that cutting global emissions would require changing agricultural systems, manufacturing, and reliance on fossil fuels for power and even replacing most power plants. Furthermore, emissions can’t be cut in an equitable way. As an example, it would be unfair to India to force it to cut emissions to the same extent as the United States, given that India creates only 3% of emissions while the United States creates nearly 10 times as much. 

The projects being developed by the scientists Kolbert interviews present problems of scale and expense. One is Klaus Lackner’s negative emissions process. It would rely on 100 million trailer-sized units that capture carbon dioxide when dry and safely release it when wet. Lackner doesn’t think the figure is daunting. It is his perspective that people first need to stop thinking of carbon dioxide as something unethical. It should be treated, rather, like sewage, as an inevitable problem that needs to be dealt with in a healthy way. The statistics that Kolbert provides in Part 3, Chapter 3 about the link between global warming and rising sea levels show that something must be done. As she points out, solutions such as geoengineering may sound “entirely crazy,” but if it can slow the Greenland ice sheet’s melting, it must be considered.

Kolbert was criticized by Guardian critic Ben Ehrenreich for failing to ask “certain glaring questions,” such as who profited from the technologies that brought humanity to this crisis. Ehrenreich points to the “asymmetrical network of exploitation that has overtaken the planet” so that the wealthy profit and the rest of the world suffers. He says, “The possibility of social change has been excluded from the start.” Yet this is not Kolbert’s concern. Her point is that humankind is at a point where the processes of global change have been set in motion and that however great the challenges of dealing with them may be, we must face them one way or another. We have no choice if we are to save “this marvelous, fragile planet.”