By the end of this century, Chicago could face the kind of searing summer heat that Las Vegas sees now. Phoenix could hit 110 degrees, 60 or more days a year.

That's not wild speculation. It's the official position of 13 federal agencies on climate change, released late last year with a warning: Local governments need to do more to prepare. Every road they build, every storm drain they put in, will have to hold up under conditions that modern civilization has never seen.

How do you plan for that? Researchers at RAND have been working on that problem for years now. Their solution: Don't try to guess what the future might bring; imagine an entire range of possible futures, and then look for solutions that work regardless of which one comes to pass. If that sounds complicated, it is.

Local governments, though, struggling with big, expensive decisions in the face of climate change, need something more than computer models. They also need public buy-in. Working with a grant from the MacArthur Foundation, Lempert and other researchers developed a decisionmaking framework to help local governments think through climate change. Its purpose is to cut through the politics and get people talking about ideas and solutions, which can then be fed into the computers.

The framework flips traditional decisionmaking on its head. To understand how, imagine buying a new family car. You think about what the next few years are likely to bring, and then buy the car that you think will best meet your needs. The idea here is like selecting the car first, and then running it through hundreds or thousands of possible scenarios—children? a move? a new job?—to see how well it holds up.

The framework allows communities to stress-test ideas and weigh the trade-offs, without requiring everyone to agree from the start on a single vision of the future. It gives them a way to think through low-regret changes they can make, and what it would take to pursue more transformative changes. It's a way through uncertainty on decisions involving many voices and different jurisdictions—a way forward for a place like the greater Pittsburgh region.

Read the full article about addressing the impacts of climate change by Doug Irving at RAND Corporation.