America’s Climate Choices

The new report by the U.S. National Academies* recommends a road map for the nation’s response to climate change.

Independent Group of Experts Established to Advise Nation and Recommend Course of Action

Today marks the end of a two-year journey — the release of the Committee on America’s Climate Choices‘ final report. The journey had its seeds in the Department of Commerce Appropriations Act of 2008, which called for the National Academy of Sciences to establish a committee to:

“investigate and study the serious and sweeping issues relating to global climate change and make recommendations regarding what steps must be taken and what strategies must be adopted in response to global climate change, including the science and technology challenges thereof.”

In 2008, the National Oceanographic and Atmospheric Administration, a branch of the Commerce Department [pdf], contracted with the National Academies to carry out the study; shortly after, I got a call from National Academy of Sciences President Ralph Cicerone asking me to serve as vice chair of the main oversight committee with the chair, Al Carnesale, former chancellor of the University of California, Los Angeles. Twenty others were selected to serve with us, ranging from climate scientists to economists to business and community leaders to politicians from both sides of the aisle.

In addition to the main committee, four panels were formed and tasked with reporting on the following areas:

Their reports were released last year. The final report, released today, integrates across the four panel reports.

In preparation for the release I’m joining Al and few other committee members in the nation’s capitol to brief members of Congress and the administration on our findings. This afternoon at the National Academies’ Keck Center, we’ll be holding an open town-hall-style meeting on our findings.

Long, Strange Trip

I’ve worked on a number of academy reports, but this one has proved to be especially complicated and memorable. First, it’s unusual for a study to have largely independent teams who must be coordinated to report on and then write a series of reports, which must then be integrated into an overarching report. Second, the study’s mandate was unusual: we weren’t asked to report on just what we know about climate change (something scientists are accustomed to), but also on what we should do about the problem. This meant charting new territory, and so we formed a committee with a broad range of expertise and experience.

The political environment was also rather unusual. At the start, it seemed a certainty that Congress would pass comprehensive climate legislation within months and there was consternation among some members that, if we didn’t hurry our report, it’d be irrelevant. My own opinion at the time was that wasn’t really an issue — our nation’s task would be decades-long and our report should try taking the longer viewpoint.

Of course all that quickly changed. First came “climategate” and then the Tea Party storm that shifted Congress sharply to the right. The idea that Congress would be passing climate legislation moved somewhere to right of nil.

In response, our committee had to make some adjustments — for example, in the wake of the climategate brouhaha, we decided to revisit the original literature on our own to assess the state of the climate science, even though that wasn’t part of our original mandate. In the process, we confirmed various aspects of our approach, such as our decision to take a decades-long view.

Our final report is also unusual for these types of multi-year efforts: since we wanted it to be read by decision makers, we made it short, to the point, and as non-technical as we technically-inclined folks could muster. So if you’re curious, I invite you to read the report for yourself. Meanwhile, here are two top-line conclusions.

The Science Reaffirmed

As noted above, we produced our study over a period when basic tenets of climate science were being questioned in the media and political arenas. After two years of rigorous study, with input from more than 100 experts, the committee confirmed that climate change:

  • is occurring,
  • is very likely caused primarily by human activities, and
  • poses significant risks to human society and the natural environment.

The committee also concluded that these risks indicate a pressing need for substantial action to:

  • limit the magnitude of climate change and
  • prepare for adapting to its impacts.

The longer we wait, the greater the risks we’ll face and the more difficult and expensive our response will be.

A Risk-Management Response: Get Out the Sandbags

Perhaps the report’s most important feature is our recommendation that America’s climate choices be driven by an iterative risk-management approach. For too long the climate change discussion has focused on what we know and how well we know it, and that has paralyzed us.

An example is the environmental community’s debate over the emissions target for 2050. When the river is rising and the threat of a flood looms large, you don’t wait till the experts tell you how high the water will rise to act. No, you get out the sandbags and develop evacuation plans.

America’s climate choices are about the decisions we as a nation must make in the face of risks. The risks of climate change are great, and while we’ll never be able to predict the future with absolute certainty, we do know:

  • the risks grow with every ton of greenhouse gases we emit into the atmosphere, and
  • because of the climate system’s inertia, the impacts of those emissions won’t be fully felt for decades.

It’s imperative to act now, we believe, to limit and adapt to climate change — waiting for any greater certainty about future climate change lacks prudence.

And yet, because of the lack of certainty, it’s not advisable to set a long-term, inflexible course, either. Instead, we recommend a flexible approach that continuously assesses and incorporates new information and knowledge so we can adjust our response accordingly. Our report describes that approach, called an iterative risk-management system, in detail.

When it comes to climate choices, the key thing for all of us to remember is, regardless of what we do or do not do, we are making a choice. Doing nothing is in fact a choice — it’s a choice to live with greater and greater risk.



The U.S. National Academies consist of the U.S. National Academy of Sciences, the U.S. National Academy of Engineering and the U.S. Institute of Medicine.

Latest twitts



Recently commented

  1. Jun 28, 2014 by Curt Richardson

    Green Groks never die they just "pine" away. Thanks for years of making science more unde ...READ MORE

  2. Jun 22, 2014 by Johnf193

    Appreciating the time and energy you put into your blog and in depth information you provi ...READ MORE

  3. Jun 19, 2014 by CrisisMaven

    Sorry to hear. I was a casual but constant reader, though this is my first comment. You do ...READ MORE