In This Is the Way the World Ends (St. Martin’s/Dunne, Sept.), a former White House staffer discusses how to battle climate change.

You state, “Climate change needs to stop being a political issue.” How did it become one?

The shift began about two decades ago, when the environmental movement embraced the emerging science of climate change and began to press for action. A number of corporate leaders—largely for political reasons—chose to create coalitions to challenge the consensus. That effort continues to echo today, despite the fact that nearly every major corporate actor now publicly accepts the scientific consensus of climate change. The so-called debate is essentially at an end. What remains is a highly partisan view of the issue.

Early in the book, you describe interviewing an eminent scientist profoundly disheartened by widespread disbelief in science. How are scientists in general coping with this?

Nearly every scientist working in the field continues to believe passionately in their work. While they’re dismayed that millions of people don’t “believe” them, it doesn’t deter them. At the same time, many now despair that leaders will act decisively and quickly to address the threats.

Dealing with climate change, you write, isn’t a matter of saving the planet, but of saving life on Earth. How did you choose the book’s apocalyptic-sounding title?

Our world includes the Earth itself, its human inhabitants, and every creature on it. Our rapidly changing climate is transforming every aspect of the world. Unless we slow, and ultimately reverse, this transformation, the world as we now know it will end.

The book oscillates between causes for optimism and causes for pessimism. Are you an optimist or a pessimist yourself?

I’m a relentless optimist. I truly believe that we will overcome our political differences on this issue and reach a consensus around solutions to reduce carbon emissions and incentives to accelerate the transition toward cleaner energy sources. We’re witnessing the end of the internal combustion engine and the birth of the distributed solar [energy] revolution. Both will be unstoppable within a decade.

You discuss big solutions like a carbon tax. What can individuals do?

Consumers don’t have to make complicated choices. Eating more plant-based food is healthier for you and reduces the pressure to keep cattle on land needed for plants. Every trip on public transportation and decision to walk helps. Use your consumer decision-making to reward responsible companies. Vote out leaders who refuse to deal with the issue. Read and talk about it. This isn’t a problem for future generations. The wolf is at the door, right now.