"We are already experiencing huge cost externalities from population hypergrowth and profligate fossil fuel use in the form of environmental devastation. Of the earth’s estimated 10 million species, 300,000 have vanished in the past fifty years. Each year, 3,000 to 30,000 species become extinct, an all-time high for the last 65 million years. Within one hundred years, between one-third and two-thirds of all birds, animals, plants, and other species will be lost. Nearly 25 percent of the 4,630 known mammal species are now threatened with extinction, along with 34 percent of fish, 25 percent of amphibians, 20 percent of reptiles, and 11 percent of birds. Even more, species are having population declines. Environmental scientists speak of an “omega point” at which the vast interconnected networks of Earth’s ecologies are so weakened that human existence is no longer possible. This is a variant of the die-off theme […], but it does raise grave questions about the ongoing project of civilization. How long might the Long Emergency last? […] Of course, after a while, an emergency becomes the norm and is no longer an emergency. Global warming is no longer a theory being disputed by political interests, but an established scientific consensus. The possible effects range from events as drastic as a hydrothermal shutdown of the Gulf Stream—meaning a much colder Europe with much-reduced agriculture—to [the] desertification of major world crop-growing areas, to the invasion of temperate regions by diseases formerly limited to the tropics, to the loss of harbor cities all over the world. Whether the cause of global warming is human activity and “greenhouse emissions,” a result of naturally occurring cycles, or a combination of the two, this does not alter the fact that it is having swift and tremendous impacts on civilization and that its effects will contribute greatly to the Long Emergency."