The last four remining candidates in the race for the 2016 Republican presidential nomination vehemently reject the fundamental findings of modern climate science. They tirelessly repeat climate myths, the refutations of which are easily found on websites such as www.skepticalscience.com. In order to obtain political and financial support, especially from sources allied with the fossil fuel industry, they may conclude that they must attack mainstream climate science. Yet science is the best process that humanity has developed to learn about natural laws. These laws show us that today's generation has its hands on the thermostat controlling future climate. Mother Nature, or the physical climate system, is not concerned with anybody’s values or convictions or political litmus tests. Mother Nature is concerned with natural laws. She always wins.

This Introduction specifies the book’s aims. Its main thesis is that a comprehensive examination of Kant’s texts displays the relevance of his ethical, legal, aesthetic, metaphysical, and historical ideas for environmental problems like climate change, despite the standard view of Kant as anthropocentrist, individualist, dualist, and nonconsequentialist. Doing so, the book builds a bridge between environmental philosophy and Kant studies by offering distinctly Kantian solutions to environmental problems. I begin with an overview of the tensions in these philosophical fields, emphasizing that the climate crisis exhibits the value of Kant’s philosophy for contemporary environmental problems. After providing empirical background on climate change, I indicate why philosophy matters for the crisis. A recent greening-the-canon movement in environmental philosophy nonetheless places Kant on the wayside. The Introduction also offers an overview of the chapters.

Chapter 5 aims to review the alleged limitations of Kantian nonconsequentialism and individualism for environmental ethics and climate ethics. I begin by assessing attempts by Hans Jonas to rework Kant’s categorical imperative as a principle for sustainability. After investigating recent efforts to reinterpret the supreme principle of morality as a ground of a sustainability ethic, I outline imperfect Kantian duties for sustainability with climate change in mind. I conclude by reflecting on duties in the face of political corruption. My goals are twofold. First, I argue that the default dismissal of Kantianism in climate ethics due to Kant’s individualism and nonconsequentialism is unfounded. Second, I suggest that contemporary defenders of Kantian sustainability have untapped conceptual resources in the Doctrine of Virtue and Doctrine of Right from The Metaphysics of Morals. The resources in these texts can provide solutions to unaddressed topics in the literature such as regulatory capture.

The measurements on which we base our estimates of the Earth’s global average surface temperature are contaminated by several serious sources of error. One of them is sampling error: We have not made measurements uniformly in space and time with identical instruments at identical locations on Earth over the whole 100-plus years of record. About 70% of the Earth is covered with ocean, and the Southern Hemisphere is nearly all ocean. For many years, few measurements were made at sea because people do not live there. And even within the remaining 30% that is land, there are vast areas (imagine the great ice-covered areas of Antarctica and Greenland) where very few people live and very few measurements were made until relatively recently. Satellite measurements and data from the Argo program, discussed earlier in this book, provide greatly improved ocean data. In general, the atmosphere over the land has warmed more than the atmosphere over the ocean, and largely because of this fact and the uneven distribution of land and ocean, the warming has not been the same in the two hemispheres.

Lewis Fry Richardson (1881–1953) became interested in computational mathematics while the subject was still in its infancy. He was a pioneer in numerical analysis, which for our purposes means using arithmetic intelligently to find approximate solutions to mathematical problems that are too complicated to solve exactly. He tried to work out a mathematical system for predicting the weather. He started by doing theoretical meteorology, deriving equations representing the physical laws that describe the evolution of the familiar meteorological properties such as wind, temperature, pressure, and humidity. Richardson’s first numerical weather forecast, obtained after a great deal of tedious calculating, was not very accurate. In fact, it was wildly inaccurate. But Richardson was ahead of his time. He was a visionary. In the late 1940s, a team of meteorologists and mathematicians using one of the earliest computers produced the first successful numerical weather prediction. By the 1950s, routine weather forecasts were being produced by techniques based closely on Richardson’s method.

The closing chapter of the book illustrates the practical implications of Kant’s political and legal philosophy for climate change. Texts like the Doctrine of Right and Toward Perpetual Peace are used to rethink the complex political and collective challenges of the climate crisis. These, once again, confound the individualist and nonconsequentialist standard reading of Kant. First, I argue that Kant’s state of nature theorizing leads to prescriptions that are compatible with and justify coercive domestic and international policy to address the crisis. Second, I zoom out to consider whether Kant’s political philosophy as a whole remains too conservative or outdated to provide guidance regarding deep climate adaptation, mitigation, and radical institutional reform, answering in the negative. I close by discussing political obligations owed to peoples, interpreted in the face of the Hobbesian call for a global climate leviathan.

When you communicate climate change science, be sure to include information on solutions. Nobody wants to hear about hopelessness, and in the case of climate change, there are many reasons to be hopeful. Climate change poses difficult problems and challenges, but there are lots of solutions that are both creative and practical and that can help solve the problems and overcome the challenges of climate change. There is no silver bullet that solves all the challenges of climate change, but there is lots of silver buckshot, including increased energy efficiency and energy conservation and much more use of sun, wind, and water to provide the energy the world needs. These renewable resources are widely available now and already cost-competitive with fossil fuels. Help people realize that not acting is also making a choice, one that commits future generations to serious climate change impacts. Research suggests that messages that may invoke fear or dismay are better received if they also include hopeful messages. Everything depends on what people and their governments do.

How will the growth of atmospheric concentrations of greenhouse gases affect the climate? When we try to foresee the future global climate, we are not simply extrapolating past behavior. We are using our scientific understanding of how the climate system works. Keeping that distinction in mind, then, the typical benchmark figure by which climate scientists now predict the climate will warm in response to a doubling of CO2 is a range rather than a single number. A range often quoted is 1.5 to 4.5 degrees Celsius (which is 2.7 to 8.1 degrees Fahrenheit). Not long ago, a widely quoted consensus number was the midpoint of this range, 3 degrees Celsius (which is 5.4 degrees Fahrenheit). A similar range, also often quoted, is 2 to 5 degrees Celsius (or 3.6 to 9.0 degrees Fahrenheit). There is more than one way to arrive at such a range, both from observations and from models, and the details are important to scientists doing this research. For other people, it is more important to be familiar with the approximate range, because estimates of climate sensitivity will continue to vary as more research is done.

The physical science portion of the Summary for Policymakers of the latest assessment report of the Intergovernmental Panel on Climate Change states that the best estimate of climate sensitivity, defined as the warming expected at equilibrium from doubling the amount of carbon dioxide in the atmosphere, is 3 degrees Celsius (or 5.4 degrees Fahrenheit). It also states that the global average surface temperature will continue to increase until at least the middle of the current (twenty-first) century. Recalling that the Paris Agreement of 2015 specified a goal or target of limiting warming to 2 degrees Celsius (or 3.6 degrees Fahrenheit), with an even more ambitious aspirational goal of 1.5 degrees Celsius (or 2.7 degrees Fahrenheit), this Summary for Policymakers states that neither of these goals will be met during the twenty-first century unless deep reductions in emissions occur. The report also states that many of the climate changes caused by greenhouse gas emissions cannot be reversed and will persist for hundreds or thousands of years. It cites global sea level rise and the loss of ice sheets and glaciers as examples of changes that will be irreversible on human time scales.

Chapter 2 continues the thread from Chapter 1, moving from objections against Kant in animal ethics to broader concerns in environmental philosophy. I begin with problematic passages from Kant’s critical texts such as the Groundwork for the Metaphysics of Morals and the Critique of Pure Reason. While Kant does not discuss the environment, the standard interpretation of Kant suggests that nature has no intrinsic value and that environments are of mere instrumental worth. Environmental philosophers are warranted to suspect that Kant’s critical philosophy may be a nonstarter given its apparent dualism and anthropocentrism. Next, I examine three camps of Kant defenders who challenge these suspicions. Some commentators defend Kant’s system, others modernize him, and some synthesize Kant with other philosophers such as Aristotle. I assess the merits of their arguments, ultimately recommending a move beyond the standard reading to address the climate crisis.