According to Wallace-Wells, a fourth of the carbon emitted by humans is absorbed by the world’s oceans, leading to a phenomenon known as ocean acidification. This process has a dramatic impact on populations of phytoplankton, which make up the base of countless aquatic food chains. Ocean acidification also threatens coral reefs, which are home to sea life that provides a half a billion people with food and income.

Another troubling phenomenon is ocean anoxification, by which large swaths of ocean water lose oxygen completely, making these dead zones incapable of supporting life. In the past 50 years, the author writes, the amount of anoxified water has increased fourfold. In a worrying observation, the author points out that “dramatic declines in ocean oxygen have played a role in many of the planet’s worst mass extinctions” (97).

As climate change continues, the air will not only become warmer; it will also become dirtier and deadlier. Some of these impacts will be direct, like when droughts produce a harmful phenomenon known as dust exposure. Others are indirect; in 2013, for example, Arctic ice-melt disrupted natural wind-ventilation patterns in China, worsening smog, which that year caused the deaths of 1.37 million people.

Already, over 10,000 people die every day from complications related to air pollution, a number the author points out is more than the total number of people who have been affected by nuclear core meltdowns.