Introduction
In "Under a White Sky," Elizabeth Kolbert takes readers on a journey through the complex and often paradoxical world of human intervention in nature. The book explores how our attempts to control and manipulate the environment have led to unforeseen consequences, and how we are now forced to intervene even further to address the problems we've created.
Kolbert, known for her Pulitzer Prize-winning book "The Sixth Extinction," brings her signature blend of scientific inquiry and engaging storytelling to this exploration of the Anthropocene – the current geological age defined by human impact on the planet. Through a series of fascinating case studies and interviews with scientists, engineers, and conservationists, she paints a vivid picture of the challenges we face and the sometimes bizarre solutions we're developing to combat them.
The title of the book refers to one potential outcome of our efforts to combat climate change: a future where solar geoengineering has turned our blue sky white. This image serves as a powerful metaphor for the unintended consequences of our actions and the difficult choices we may need to make to ensure our survival on this planet.
The Disappearing Louisiana Coastline
Kolbert begins her exploration with a visit to Plaquemines Parish in Louisiana, one of the fastest-disappearing places on Earth. This region, situated at the southeasternmost tip of the state, now consists of little more than two narrow strips of land clinging to the end of the Mississippi River.
The author paints a vivid picture of a landscape in flux, where even teenagers can remember buildings that once stood on land now submerged beneath the water. This rapid land loss is not unique to Plaquemines Parish but is happening along the entire Louisiana coastline. Every hour and a half, an area equivalent to a football field disappears beneath the waves.
The irony of this situation is that the very system designed to protect the land is causing its destruction. The vast network of artificial levees, floodwalls, and retaining walls built to keep the water at bay is actually responsible for the coastline's rapid shrinkage.
Kolbert explains the historical context of this problem. Before human intervention, the Mississippi River carried hundreds of millions of tons of sediment south each year. The annual spring floods would deposit this sediment onto the surrounding plain, gradually building up the Louisiana coastline over time.
However, when French settlers arrived in Louisiana, they began constructing levees to prevent the river from flooding their cities. While these levees have largely succeeded in their primary goal, they've also disrupted the natural process of land formation. The Mississippi can no longer deposit its sediment, meaning no new earth is being layered atop the old. Simultaneously, the existing soil, which is soft and watery, is becoming more compact over time, leading to land shrinkage.
To combat this issue, humans are now attempting to do the river's job. Kolbert describes an ongoing project that involves using a massive drill-bit to stir up sediment from the river bed, which is then sucked through a pipe and discharged to create new land areas. While this effort is admirable, it simply can't keep pace with the rate of land loss.
In response to this crisis, the Mississippi's Coastal Protection and Restoration Authority has proposed a bold solution: punching eight massive holes through the levees surrounding the Mississippi. The idea is to "reestablish the natural sediment deposition process." Kolbert points out the irony in this plan – humans must intervene again to allow a "natural" process to resume.
This case study sets the tone for the rest of the book, highlighting the complex relationship between human intervention and natural processes, and the often unexpected consequences of our attempts to control nature.
The Chicago Sanitary and Ship Canal: A Tale of Unintended Consequences
From Louisiana, Kolbert takes us to Chicago, where another example of human intervention in nature has led to unforeseen ecological challenges. The focus here is on the Chicago Sanitary and Ship Canal, a 160-foot-wide waterway that plays a crucial but unglamorous role in the city's infrastructure.
The author provides historical context, explaining that before the canal's existence, all of Chicago's waste – including human feces, animal manure, and rotting animal parts – was dumped directly into the Chicago River. This waste would then flow into Lake Michigan, the city's only source of drinking water, leading to frequent outbreaks of typhoid and cholera.
The Sanitary and Ship Canal, opened around 1900, was designed to solve this problem. It literally changed the direction of the Chicago River, making it flow away from Lake Michigan and into the nearby Illinois River instead. While this engineering feat successfully addressed the waste issue, it created a new set of ecological problems that required further intervention.
Kolbert explains that the canal connected Lake Michigan to multiple nearby rivers, ecosystems that were once separate. This new connection allowed for easy travel not just for humans, ships, and waste, but also for fish. The author emphasizes the significance of this seemingly small detail, pointing out that ecosystems in Lake Michigan and the surrounding rivers are fragile. The introduction of non-native species can have devastating effects.
To address this new threat, the U.S. Army Corps of Engineers installed electric barriers in the canal, designed to keep out certain fish species. Kolbert introduces us to the current "public enemy number one" – the Asian carp. This term actually refers to four different species of fish that were brought to the Mississippi River in the 1960s as a biological control measure to manage aquatic weeds.
The author vividly describes the voracious appetite of these carp, which feed almost constantly and can outcompete or overeat native species, greatly disrupting the ecosystem. The potential consequences of even a single carp breaching Lake Michigan through the Sanitary and Ship Canal could be disastrous.
While the electric barriers have been effective so far, they aren't foolproof, necessitating additional solutions. Kolbert introduces us to Kevin Irons from the Illinois Department of Natural Resources, who came up with an unusual idea: CarpFest, an event designed to create demand for carp. The thinking behind this was that humans are skilled at overfishing, so why not harness this ability to address the carp problem?
This anecdote serves as another example of the complex and often counterintuitive solutions we devise to address problems created by our earlier interventions in nature. Kolbert expresses skepticism about the effectiveness of this particular solution, highlighting the ongoing challenges we face in managing the unintended consequences of our actions.
Gene Editing: A New Frontier in Ecosystem Management
Kolbert then shifts our attention to a more controversial and cutting-edge approach to managing invasive species: genetic modification. She takes us to Australia, where the introduction of cane toads in the mid-1800s has had devastating consequences for native species.
The author provides a vivid description of these amphibians: large, splotchy brown creatures weighing up to six pounds, with eyes set in thick ridges giving them a permanently leery expression. Originally brought to the Caribbean to combat beetle grubs that were destroying sugarcane plants, the toads were later introduced to Australia, where they quickly spread and made themselves at home.
Kolbert explains that the major problem with cane toads is their toxicity. When frightened or eaten, the toads' glands release an enzyme called bufotoxin hydrolase, which mixes with the toad's natural poison and multiplies its potency a hundredfold. This potent combination is deadly to many native Australian species that have no evolutionary experience with such toxins.
While Australians have devised various ingenious methods for trapping and killing the toads, scientists have proposed a different solution: genetic modification. Kolbert introduces us to scientist Mark Tizard, who wondered if it might be possible to disable the genes responsible for producing the deadly enzyme, effectively creating detoxified toads.
The author then explains how another scientist, Caitlin Cooper, used CRISPR technology to edit out the gene that codes for bufotoxin hydrolase in cane toads. CRISPR, Kolbert clarifies, encompasses several different techniques, but essentially involves cutting out a section of DNA and either disabling it or replacing it with something new.
The challenge now lies in determining what to do with these newly detoxified toads. One potential solution is to use them as a training device for native animals. Australia has no native toad species, so local animals don't instinctively know to avoid eating them. By feeding animals the detoxified toads, they would get sick but not die, potentially learning to steer clear of toads in the future.
Kolbert acknowledges that the idea of gene-editing animals feels uncomfortable to many people. However, she presents Tizard's counterargument: the environment they're working with is already genetically modified by the presence of invasive species – their entire genomes don't belong there. In contrast, gene-editing involves altering just small pieces of DNA, with the ultimate goal of restoring balance to traumatized ecosystems.
This case study introduces readers to the complex ethical and practical considerations surrounding the use of advanced biotechnology in conservation efforts. It raises important questions about the extent to which we should intervene in nature and the potential risks and benefits of such interventions.
The Plight of the Devils Hole Pupfish
Kolbert next takes us to the edge of Death Valley, California, to explore a unique case of species conservation. Here, in a cavern known as Devils Hole, swims one of the rarest fish in the world: the Devils Hole pupfish.
The author paints a vivid picture of these tiny, deep blue, inch-long fish, explaining that their name comes from the male pupfish's habit of wrestling each other in a way that vaguely resembles puppies at play. What makes these fish truly remarkable is their extreme rarity – they exist only in this one location.
Kolbert describes the extraordinary efforts made by biologists to ensure the survival of this species. Four times a year, a team from three different government agencies travels to Devils Hole to conduct a pupfish census. The author reveals that in 2006, they counted just 38 pupfish, though the number has since grown to over two hundred.
The story of how the pupfish's numbers dwindled so low is a familiar tale of human intervention and unintended consequences. In the 1950s and '60s, developers began buying up land near Devils Hole and pumping water from the aquifer that feeds it. Over time, this greatly reduced the size of a part of Devils Hole called "the shelf," where the pupfish lay their eggs and find food.
By 1972, the shelf had shrunk to barely a quarter of its original size. While a Supreme Court order eventually halted the pumping and water levels rose again, they remained much lower than before, leaving the food web fragile and unstable. To ensure the pupfish's survival, the National Park Service now delivers supplemental meals to Devils Hole.
But the efforts to save the pupfish don't stop there. Kolbert describes a fake version of Devils Hole, located about a mile from the real one. This hundred-thousand-gallon refuge tank is designed to mimic the cavern in every way except for those that harm the pupfish. When the author visited in 2013, about fifty adult fish lived in this artificial habitat.
Kolbert uses this example to raise a philosophical question: Why do we go to such lengths to save a single species of tiny fish? She acknowledges that our planet has seen numerous extinction events throughout its history. Yet, for some reason, we take issue with being responsible for another species' destruction.
This has led to the creation of what Kolbert calls "conservation-reliant animals" like the pupfish. After pushing them to the brink of extinction through our actions, these species can now only survive with our continued assistance. This case study serves as a poignant example of the complex relationship between human activity and biodiversity conservation, highlighting the ongoing responsibilities we've created for ourselves through our interventions in nature.
Coral Reefs: Assisted Evolution in the Face of Climate Change
Kolbert then turns our attention to one of the most visible and alarming consequences of climate change: the destruction of coral reefs. She begins by highlighting the devastating impact on Caribbean coral reefs in the 1980s, where a combination of development, overfishing, and pollution led to the disappearance of half of the Caribbean's coral in just one decade.
The author emphasizes that this problem isn't limited to the Caribbean. Climate change is warming the oceans to temperatures many corals can't tolerate. Kolbert cites a specific example from 1988, when a major spike in water temperatures resulted in the death of more than 15 percent of corals worldwide.
But warming is just one aspect of the problem. Kolbert explains that changes in ocean chemistry caused by fossil fuel emissions are also threatening coral reefs. With all these issues combined, the world's reefs are in danger of disappearing forever. However, she introduces a glimmer of hope: the possibility of saving the reefs with a little help from evolution.
The author introduces us to Ruth Gates, a marine biologist with a particular passion for corals. Despite being deeply saddened by the destruction of the reefs, Gates had hope that they could be saved – and she had an innovative idea about how to do it.
Kolbert explains the process of coral bleaching: when water temperatures rise, corals expel the tiny plants that live in their cells, causing the corals to turn white and ultimately die. However, Gates knew that after a bleaching event, some corals can bounce back by attracting new plants. She wondered if this resilience was due to genetic advantages in certain corals, and if so, whether it would be possible to breed corals for these advantageous traits.
Although Gates sadly passed away before she could see her experiments through, other scientists are now testing out her ideas. Kolbert describes the process: corals are first exposed to high levels of stress. Those that survive are then selectively crossbred. Their offspring are subjected to even more stress, and the process repeats. Over time, this creates a kind of assisted evolution, resulting in "super corals" that could potentially be used to repopulate the world's coral reefs.
The author acknowledges that it's unlikely corals will adapt naturally before the oceans grow too hot, making this assisted evolution potentially our only option. We're faced with a stark choice: help corals evolve at a more rapid pace, or simply let them die.
Kolbert emphasizes that the latter option isn't as simple as it might seem. The number of creatures that depend on reefs for survival is unknown, and their fate is tied to that of the corals. However, she also notes that even breeding "super corals" may not be enough – what we really need is to address the root cause by tackling climate change.
This case study illustrates the extreme measures we're considering to save ecosystems threatened by climate change. It raises important questions about the ethics and practicality of such interventions, and whether they can truly succeed without addressing the underlying causes of environmental degradation.
Carbon Removal: Fighting Fire with Fire
As Kolbert delves deeper into the climate crisis, she introduces us to the concept of carbon removal as a potential solution to combat global warming. She begins by providing historical context, explaining that for the last ten thousand years or so, Earth has enjoyed a period of remarkably stable climate. This stability allowed humans to settle permanently, build farms and cities, and develop civilizations.
However, our success came at a cost. As we chopped down and burned forests to clear land, we released CO2 into the atmosphere. While these quantities were initially small, they were impactful, causing overall atmospheric CO2 levels to remain constant when they should have been falling in accordance with natural cycles.
Kolbert emphasizes that since then, human influence over emissions – and by extension, the climate – has only grown stronger. We may have reached a point where simply reducing our emissions is no longer sufficient; we may need to actively remove carbon from the atmosphere.
The author vividly describes the potential consequences of high atmospheric CO2 levels: longer droughts, fiercer storms, and increasingly devastating heatwaves. She notes that scientists have difficulty predicting exactly how hot the world can get before we reach a point of no return, though officially, the threshold is set at an increase of 2 degrees Celsius.
Kolbert explains that staying below this 2-degree threshold would require major changes: revamping agriculture, transforming manufacturing, and scrapping all traditional gas- and diesel-powered vehicles. Recognizing the enormity of this task, she introduces carbon removal as a potential solution that could swing the math in our favor.
The basic idea behind carbon removal is to extract large amounts of CO2 from the atmosphere, essentially creating negative emissions. Kolbert describes various methods of carbon removal, focusing on one that uses rocks, which are one of Earth's largest reservoirs of CO2.
She takes us to a power station in Iceland, where CO2 is captured rather than allowed to escape into the air. This captured CO2 is then mixed with water, creating a kind of high-pressure club soda. This mixture is injected deep underground, where it reacts with the volcanic rock that exists in Iceland and then mineralizes.
Kolbert points out an interesting fact: this process would eventually happen naturally without human intervention. All the CO2 we've emitted would, over time, return to the earth and turn to stone. The problem is that this natural process would take hundreds of thousands of years – time we simply don't have in the face of rapid climate change.
This case study illustrates how we're attempting to accelerate natural processes to combat the very problems we've created. It raises questions about the scale at which we need to intervene in natural systems to address climate change, and whether such interventions can be effective and sustainable in the long term.
Solar Geoengineering: A Controversial Solution
In the final section of her book, Kolbert introduces us to one of the most controversial proposed solutions to climate change: solar geoengineering. She begins with a historical anecdote about the eruption of Mount Tambora in Indonesia in 1815, which released over a hundred million tons of gas and fine particles into the atmosphere. These particles blocked the sun, resulting in frigid temperatures that caused harvests to fail and potentially millions of people to starve.
While this event was clearly a catastrophe, Kolbert suggests that it might teach us something about fighting climate change. If volcanoes can lower global temperatures by adding particles into the atmosphere, could we potentially do the same?
The author explains that this is the basic principle behind solar geoengineering. The idea involves using airplanes to fly up to the stratosphere – the second-lowest layer of the atmosphere – and pump it full of reflective particles. This would result in less sunlight reaching the planet, thereby cooling temperatures.
However, Kolbert is quick to point out the catch. While solar geoengineering would address the symptoms of climate change, it wouldn't tackle the root cause: global carbon emissions released through human industry. In fact, she argues that it would make us utterly dependent on the particle payloads keeping the planet cool.
The author outlines several potential issues with this approach. First, the particles injected into the atmosphere would eventually fall back down, meaning we'd have to keep replenishing them. She raises the question of what might happen if an external event – like a war or a pandemic – caused us to temporarily stop these injections. The result could be a sudden, shocking spike in global temperatures as all the warming that had been diverted suddenly entered the atmosphere.
Furthermore, Kolbert explains that to keep up with ongoing warming, the payloads would need to grow ever bigger, and the flights ever more frequent. This escalation increases the likelihood of strange side effects. One particularly striking potential consequence she mentions is a change in the appearance of the sky itself. Due to the color of the particles, our familiar blue skies could turn white – hence the title of the book.
Despite these concerns, Kolbert notes that several scientists have described solar geoengineering as "inevitable." She leaves us with the unsettling image of a future where, in our efforts to combat global warming, we gaze up at a white sky rather than a blue one.
This final case study serves as a powerful illustration of the extreme measures we're considering in our fight against climate change. It highlights the potential for unintended consequences in our attempts to manipulate the environment on a global scale, and raises important questions about the risks we're willing to take to ensure our survival on this planet.
Conclusion
In "Under a White Sky," Elizabeth Kolbert takes us on a journey through the complex and often paradoxical world of human intervention in nature. From the disappearing coastlines of Louisiana to the gene-edited toads of Australia, from the conservation-reliant pupfish of Death Valley to the potential white skies of a geoengineered future, she paints a vivid picture of the Anthropocene – an age defined by human impact on the planet.
Throughout the book, Kolbert highlights a recurring theme: our attempts to solve problems often create new, unforeseen issues that require further intervention. The levees built to protect Louisiana from flooding are causing its coastline to disappear. The canal designed to keep Chicago's drinking water clean has become a potential gateway for invasive species. Our efforts to combat climate change might lead to a future where we're dependent on continual technological intervention just to maintain a habitable planet.
Yet, Kolbert also shows us the ingenuity and determination of scientists, engineers, and conservationists who are working tirelessly to address these challenges. From breeding "super corals" to withstand warming oceans, to capturing and mineralizing carbon dioxide, to considering radical solutions like solar geoengineering, humans are pushing the boundaries of science and technology in our efforts to save our planet – and ourselves.
The author doesn't shy away from the ethical dilemmas these interventions raise. Should we genetically modify species to help them survive in a changing world? Is it right to devote enormous resources to saving a single species like the pupfish? Are we prepared for the potential consequences of geoengineering our planet?
Kolbert leaves us with a sobering realization: in many cases, the choice is no longer between intervention and leaving nature alone. We've already intervened, often with devastating consequences. Now, our choice is between further intervention and allowing the collapse of ecosystems and species we've pushed to the brink.
"Under a White Sky" is not a book of easy answers or false optimism. Instead, it's a clear-eyed look at the reality of our situation and the complex, often uncomfortable solutions we're considering. It's a call for us to recognize the full extent of our impact on the planet and to take responsibility for the world we're creating.
As we face the challenges of the Anthropocene, Kolbert's book reminds us that our fate is inextricably linked with that of the natural world. The solutions we devise, however innovative or extreme, must ultimately aim to restore balance to the ecosystems we've disrupted. Whether we succeed in this monumental task will determine not just the color of our sky, but the very future of life on Earth.