Burning Down the House

Although Wallace-Wells protests that he’s not an environmentalist, or even drawn to nature (“I’ve never gone camping, not willingly anyway”), the environment definitely has his attention now. With mournful hindsight, he explains how we were convinced that we could survive with a 2 degrees Celsius increase in average global temperatures over preindustrial levels, a figure first introduced in 1975 by William Nordhaus, a Nobel prize–winning economist at Yale, as a safe upper limit. As 2 degrees was a conveniently easy number to grasp, it became repeated so often that policy negotiators affirmed it as a target at the UN’s 2009 Copenhagen climate summit. We now know that 2 degrees would be calamitous: “Major cities in the equatorial band of the planet will become unlivable.” In the Paris Agreement of 2015, 1.5 degrees was deemed a safer limit. At 2 degrees of warming, one study estimates, 150 million more people would die from air pollution alone than they would after 1.5 degrees. (If we include other climate-driven causes, according to the Intergovernmental Panel on Climate Change, that extra half-degree would lead to hundreds of millions more deaths.) But after watching Houston drown, California burn, and chunks of Antarctica and Louisiana dissolve, it appears that “safe” is a relative statement—currently we are only at 1 degree above preindustrial temperatures.

The preindustrial level of atmospheric carbon dioxide was 280 parts per million. We are now at 410 ppm. The last time that was the case, three million years ago, seas were about 80 feet higher. A rise of 2 degrees Celsius would be around 450 ppm, but, says Wallace-Wells, we’re currently headed beyond 500 ppm. The last time that happened on Earth, seas were 130 feet higher, he writes, envisioning an eastern seaboard moved miles inland, to Interstate 95. Forget Long Island, New York City, and nearly half of New Jersey. It’s unclear how long it takes for oceans to rise in accordance with CO2 concentrations, but you wouldn’t want to find out the hard way.

Unfortunately, we’re set to sail through 1.5 and 2 degree increases in the next few decades and keep going. We’re presently on course for a rise of somewhere between 3 and 4 degrees Celsius, possibly more—our current trajectory, the UN warns, could even reach an 8 degree increase by this century’s end. At that level, anyone still in the tropics “would not be able to move around outside without dying,” Wallace-Wells writes.

Wallace-Wells has been faulted for not offering solutions—but really, what could he say? We now burn 80 percent more coal than we did in 2000, even though solar energy costs have fallen 80 percent in that period. His dismaying conclusion is that “solar isn’t eating away at fossil fuel use…it’s just buttressing it. To the market, this is growth; to human civilization, it is almost suicide.”

He allows that through carbon-capture or geoengineering “or other now-unfathomable innovations, we may conjure new solutions,” but at best, he says, these will “bring the planet closer to a state we would today regard as merely grim, rather than apocalyptic.” Having read for years about geoengineering plans to reflect sunlight back into space by sending up planes to seed the stratosphere with sulfates, and to enhance the reflectivity of clouds by spraying salt to brighten them, and about machines that can suck carbon dioxide from the atmosphere, I know of some who might challenge that—but so far, none of these ideas has reached even a pilot level, let alone commercialization scale.

Current carbon-capture prototypes filter CO2 from a polluter’s exhaust so that it can be converted back into more carbon-based fuel. But this would require building enough machines to cleanse the entire atmosphere of emissions from every company and cookfire, and then burying all that captured CO2 so it can never escape—a huge and dubious undertaking. Likewise, a program to deflect solar radiation by spraying particles—as Mt. Pinatubo’s eruption did in 1991, slightly cooling the climate for two years before its dust settled back to Earth—would have to continue in perpetuity to work. Such a program would alter planetary rainfall patterns in unpredictable ways and do nothing to curb ocean acidification. Imagine getting all the world’s nations to agree to tinker with the atmosphere if it meant some of them might end up even drier than before. Several major environmental organizations that once opposed such schemes are now willing to discuss them (the goals of the Paris Agreement depend on yet-uninvented mass-scale technologies to remove atmospheric carbon), underscoring Wallace-Wells’s argument that the situation is dire indeed.

His book gives other examples of why technology probably can’t get us out of the mess that technology caused in the first place. That includes one of the biggest innovations of the twentieth century: the Green Revolution, which more than doubled grain harvests in the 1960s by selective crossbreeding of wheat, corn, and rice to get extra kernels per stalk. Wallace-Wells notes that Norman Borlaug, the agronomist behind these advances, is credited with saving a billion lives by staving off the famines that eighteenth-century demographic economist Thomas Malthus and Paul Ehrlich, author of The Population Bomb, had both predicted would inevitably result from population growth. But Borlaug never claimed to have eliminated the possibility of more famine. Upon accepting his Nobel Peace Prize in 1970, he warned that without population controls, enhanced food production would paradoxically lead to even more hunger, because people spared by famine would give birth to more people who would continually need more food.

For the rest of his life Borlaug campaigned, in vain, for universal family planning. His efforts were especially undermined when in 1984, at the International Conference on Population in Mexico City, Ronald Reagan instituted the “Global Gag Rule,” prohibiting US funding assistance for any aid program, American or foreign, that mentioned abortion as a family planning option—a rule that every Republican president since has supported. As Borlaug feared, his high-yield cereals, along with the invention of artificial nitrogen fertilizer a few decades earlier, combined to quadruple the global population during the twentieth century—a growth unprecedented in biological history for any large species. As a result, nearly half the unfrozen Earth is now devoted to growing or grazing food for humans, while other species dwindle or just disappear. Food production, reports Wallace-Wells, is also responsible for at least one third of all greenhouse gas emissions (some estimates are as high as one half when all aspects of food consumption—including shipping, refrigeration, and agrochemical costs—are considered).

The Uninhabitable Earth makes only scant reference to the holocaust that climate change is wreaking on biodiversity. (One million species are now at risk of extinction, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services reported recently.)

And that’s just the effects from heat. Absorption of CO2 has already made the ocean 30 percent more acidic, with pH expected to decline “well beyond what fish and other marine organisms can tolerate” by the end of this century, he writes, citing another paper. According to the Intergovernmental Panel on Climate Change, current acidification rates of seas and lakes already may be the highest in 300 million years.

McKibben shares some other harrowing examples of threatened fauna, from insects to lions, but although it’s been understood since Noah’s time that we need other species, readers best relate to our own, so like Wallace-Wells McKibben soon circles back to humans. Major cities like Cape Town and São Paulo (and several in India and China) have come within mere days of running out of water; it’s just a matter of time until one does. Outdoor work and maintenance will be halted more frequently as urban thermometers exceed 120 degrees Fahrenheit. Grain harvests will drop as temperatures rise. Insurance companies will go bankrupt after successive biblical storms destroy trillions of dollars of property. Refugees running everywhere. This won’t stop.