The Global Warming Challenge

Michael Goldfarb’s article “The Polar Bears Are All Right” in the Weekly Standard questions the current push to have polar bears listed as a “threated species” as a policy implemented under climate change. Below is an excerpt, full text available.

Polar bears, on the other hand, are expected to see few benefits, even if the threat they face from warming is a matter of dispute. Lindzen flatly describes worry over polar bears as “gibberish.” “Polar bears are going up in number,” he says. “They’re not worried; they can swim a hundred kilometers.” The notion of threatened polar bear populations was recently challenged by J. Scott Armstrong, a professor at the Wharton School of Business at the University of Pennsylvania. In an article for the journal Interfaces, Armstrong and his coauthors argued that a series of complex and “erroneous assumptions” undergird much of the research showing polar bears at risk, and they offer compelling evidence that the animals have survived far warmer conditions in the past.

Still there is a push to have the polar bear officially listed as a “threatened species.” Hugh Hewitt, who practices natural resources law in addition to hosting a radio show, explained in a recent column that the move would clear a path for environmentalists to “argue that every federal permit that allows directly or indirectly for increased emissions of hydrocarbons is a federal act that might impact the polar bear.” Such permits would thus be subject to a new range of environmental regulations affecting all manner of industry.

April 15, 2008

J. Scott Armstrong

I have been working on a book on persuasion for the past 14 years. Having reviewed the evidence, I concluded that rational arguments are not effective in leading people to change strongly held opinions—especially not in the short term. This intransigence is a problem, because if peoples’ opinions are at odds with the facts, they are likely to act and vote in ways that cause harm to themselves and others.

There is a solution, however, and that is to persuade oneself. In other words, in order to reduce the risk of making bad decisions each of us should identify what information would, if it existed, lead us to change our opinion about important issues—such as whether humanity is faced with a problem of dangerous manmade global warming.

My own self-persuasion journey on the topic of global warming started more than a year ago. Needing a featured talk for the International Symposium on Forecasting in June 2007, I discussed possible topics with Kesten Green. We concluded that global warming was an important issue that hinged on long-term forecasts. As it happened, Kevin Trenberth, an IPCC lead author, was a keynote speaker at the symposium. I sent him a cordial note and asked him if he would share his slides with me prior to the conference. He said “no.” This experience was repeated in my contacts with other people who warn of dangerous global warming. When I have asked for evidence, data, or published papers to support their position (such as the statement that all scientists agree that global warming will occur in the future), I have typically received either no reply or a refusal. Such behavior is strange for scientists. In contrast, global warming skeptics have been anxious to make their papers and the data available.

My review of the evidence led me to become a skeptic. Indeed, we were unable to find a single scientific forecast of global warming despite contacting over one hundred global warming advocates directly, and also issuing our request in talks, on email lists, and on web sites. We kept the global warming advocates informed of our research and asked them for suggestions and peer review. In return we received mostly silence although there were some nasty comments and some people who asked that they be removed from our mailing list.

My conclusion is that the scientific evidence clearly favors the skeptics’ position. In addition, I believe that the global warming advocates have violated many of the tenets of the scientific method; the global warming advocates say that it happens on both sides, but that has not been my observation.

So I have made a decision based on the evidence that I needed to convince me. In addition, in our papers, we have also described the information that would change our minds yet again—in effect, proper forecasts would convince us. We are hoping to do some of this forecasting ourselves, but it is costly and so far we have not obtained funding. Our two papers to date (available at http://publicpolicyforecasting.com) have been written with no funding.

The problem is essentially a forecasting problem. Those who are forecasting global warming have demonstrated little knowledge of how to forecast. This is unfortunate as there have been many useful (and often surprising) findings from the research on forecasting that have been published, especially over the past half century. Moreover, global warming advocates tend to become upset when the research findings are pointed out and they claim that different principles apply to them. We have replied by asking them to tell us which principles differ and to provide the evidence for their assertions. They seldom reply, and when they do, they do not provide evidence; at least, not yet.

April 9, 2008

The Honorable Barbara Boxer
Chairman, Committee on Environment and Public Works
United States Senate
Washington, D.C. 20510

Dear Senator Boxer,

Since presenting the presentation of my testimony on the validity of the government polar bear forecasts at your U.S. Senate Environment and Public Works Committee hearing on January 30 of this year, I along with my co-authors Kesten Green of Monash University in Australia and Willie Soon of the Harvard-Smithsonian Center for Astrophysics, have continued to work on our research paper on the methods that were used to make the forecasts. Thanks to extensive peer review, we have made many improvements. I enclose a copy of the paper. The current version of the paper is always available at http://publicpolicyforecasting.com.

I am pleased to inform you that it has now been accepted (subject to further revisions) by Interfaces. Thus, it stands as the only peer-reviewed study on polar bear forecasting that has been accepted for journal publication.

We found the forecasts of declining polar bear numbers contained in the government’s administrative reports were not the product of scientific forecasting methods. Given the large current population of bears and the upward trend in the population, our findings lead to the conclusion that there is no scientific basis for listing polar bears. Indeed, a reliance on evidence-based forecasting suggests that it is more likely that the polar bear population will increase rather than decrease.

I would be happy to discuss the details of our paper with you.

Sincerely,

Professor J. Scott Armstrong, The Wharton School

armstrong@wharton.upenn.edu
jscottarmstrong.com

Professor J. Scott Armstrong responds to Andrew C. Revkin’s April 1st New York Times article, “Gore Group Plans Ad Blitz on Global Warming” through Google News Comments:

Gore’s Global Warming Campaign Raises Ethical and Legal Questions

As a professor who has taught advertising at the Wharton School since the 1970s, I wonder whether Mr. Gore’s advertising campaign raises ethical and legal concerns.

Advertisers should be able to support their claims. Yet, as I have pointed out to Mr. Gore on numerous occasions since June 2007, there are no scientific forecasts to support claims of global warming. Details on this conclusion can be found in a paper that I and Dr. Kesten Green published titled, “Global Warming: Forecasts by Scientists versus Scientific Forecasts,” (available in full text at http://publicpolicyforecasting.com). Advertisers should be expected to support their claims. In this regard, on June 19, 2007, I asked Mr. Gore to participate in a Global Warming Challenge to test his theories (see http://theclimatebet.com ). He has not agreed to the challenge.

On page 10 of his book, The Assault on Reason, Mr. Gore stated:

“We must . . . stop tolerating the rejection and distortion of
science. We must insist on an end to the cynical use of pseudostudies
known to be false for the purpose of intentionally clouding the
public’s ability to discern the truth. . . . The climate crisis, in
particular, could cause us to reject and transcend ideologically
based distortions of the best available scientific evidence.”

Consistent with this, in March of this year I asked him: “When and under what conditions would you be willing to engage in a scientific test of your forecasts?”

I am still waiting for an answer.

I expect that Mr. Gore’s campaign will avoid two-sided messages such as might might be found in educational programs or in messages related to health (e.g., pharmaceutical advertising). Instead they will be based heavily on innuendos, anecdotes, emotion, and repetition of claims. These are approaches that are commonly used for propaganda campaigns that lack scientific evidence.

J. Scott Armstrong

The U. S. government commissioned studies to support the listing of polar bears as a threatened or endangered species. Polar bear numbers are currently high and the population has been increasing rapidly in recent decades. Everyone likes polar bears, so this is good news. A decision to list would require forecasts that the current upward population trend will reverse. The government studies concluded that polar bear populations would decrease substantially.

Decision makers and the public should expect people who make forecasts to be familiar with the scientific principles of forecasting just as a patient expects his physician to be familiar with the procedures dictated by medical science. Three scientists, J. Scott Armstrong of the University of Pennsylvania, Kesten Green of Monash University, and Willie Soon of The Harvard-Smithsonian Center for Astrophysics, audited the government studies to assess whether they were consistent with forecasting principles. Their paper, “Polar Bear Population Forecasts: A Public-Policy Forecasting Audit,” has been accepted for publication in the management science journal Interfaces. It is the only peer-reviewed paper on polar bear population forecasting that has been accepted for publication in an academic journal.

They concluded that the government forecasts were based on false assumptions and their polar bear population forecasts contravened many principles for scientific forecasting. Indeed, the reports followed fewer than one-sixth of the relevant principles. Given the importance of the forecasts, all principles should be properly applied. In short, the government reports do not provide relevant information for this decision.

Research shows that for issues such as the population of polar bears—situations that are complex and where there is much uncertainty—the best forecast is that things will follow a “random walk;” in effect, this model states that the most recent value is the best forecast for all periods in the future. Because the polar bear population has been increasing over recent decades, however, a continuation of that trend over the short term is possible.

Copies of Armstrong, Green and Soon’s forthcoming paper are available at http://publicpolicyforecasting.com.

The extended due date for the Global Warming Challenge passed with no word from Mr. Gore. Although he and Professor Armstrong have had a number of communications, Mr. Gore offered no response to the key question:

“When and under what conditions would you be willing to engage in a scientific test of your forecasts?”

Validation of forecasting methods is a key issue in climate change because, although we know that climate varies, we have been unable to locate a single scientific forecast that supports global warming. If Mr. Gore or anyone else is aware of such a forecast, they should reveal the source to the scientific community. Claims that science supports global warming forecasts have, to date, failed to provide sources.

A history of the Global Warning Challenge is provided at http://theclimatebet.com. It includes all correspondence between Scott Armstrong and Al Gore. The site will post all papers that purport to provide scientific forecasts of global warming. The papers must provide full disclosure on how the forecasts were made, as full disclosure is one of the basic principles of science.

Scott Armstrong’s letter to Al Gore follows:

March 28, 2008
Honorable Albert Gore
2100 West End Avenue,
Suite 620
Nashville, TN 37203
Fax: 615-327-2227

Dear Mr. Gore,

The extended deadline for the Global Warming Challenge has passed and, despite the fact that I have responded to all of your concerns to date regarding the challenge, you have not been willing to engage in a scientific test of your forecasts of dangerous global warming.

Despite our literature searches and our appeals both on the Internet and in our published paper on climate change, my colleague and I have been unable to find a single scientific forecast to support global warming. If you are aware of such a study, I appeal to you directly to reveal it to the scientific community so that it can be subject to peer review and so the public can see the scientific basis for your claims.

In addition we need to continue scientific studies. Thus, I pose this question:

“When and under what conditions would you be willing to engage in a scientific test of your global warming forecasts?”

I look forward to your responses. By your own words, the global warming issue remains an important one for the future of the world. Given the enormous expenditures on this issue, I hope that as a concerned and influential citizen, you will take an active role in encouraging the application of science to this issue.

Sincerely,

J. Scott Armstrong

Armstrong’s AEI talk titled Strengths and Weaknesses of Climate Models on Tuesday, February 26th, 2008 is available at the American Enterprise Institute for Public Policy Research website in both audio and video format.

Other attendees included: Daniel Botkin, a research professor in the Department of Ecology, Evolution and Marine Biology at the University of California, Santa Barbara; Orrin Pilkey, the James B. Duke Professor Emeritus of Geology at Duke University; Jim Manzi, CEO of Applied Predictive Technologies; Stephen F. Hayward, AEI’s F. K. Weyerhaeuser Fellow; and Kenneth P. Green, a resident scholar at AEI.

On Tuesday February 26th, 2008, Scott Armstrong will speak at a panel on the Strengths and Weaknesses of Climate Models, hosted by the American Enterprise Institute in Washington D.C. A summary of the event is available by clicking on, and full event details are available at the AEI website.

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On June 19, 2007, Professor Armstrong proposed the Global Warming Challenge to Mr. Gore in an effort to stimulate a scientific approach to forecasting climate change. The Challenge asked that Armstrong and Gore each put $10,000 into a Charitable Trust Fund on December 1, 2007. Armstrong bet that over the next ten years he could forecast temperature change more accurately than any climate model that Mr. Gore might nominate. (Armstrong’s forecast would be that global mean temperature would not change over the ten years.)

On July 6, Mr. Gore sent a cordial reply stating that he was too busy. In response, on November 28, 2007, Dr. Armstrong extended the deadline to March 26, 2008, and made the task easier: Mr. Gore was asked merely to provide a checkmark beside a leading climate model and to sign his name.

Mr. Gore’s spokesperson replied on Armstrong’s answering phone on around February 5. The caller apologized for being so late for responding to the November 28 letter. She said, “Senator Gore declines.” No reason was given. She said to call if there were any questions. Attempts to reach her by phone failed despite leaving callback messages. Armstrong then contacted her by email with questions for Mr. Gore:

“You have made dramatic forecasts of a dire future and have asked people to make big sacrifices on the basis of those forecasts. I would be grateful if you would explain:

1. Why are you unwilling to back your forecasts in a challenge intended to promote scientific forecasting of climate change?

2. Under what conditions would you be willing to back your forecasts in a challenge against my forecasts from a simple scientific method that is appropriate in situations of high uncertainty: the naïve “no change” method?”

The spokesperson said that with respect to question #1, “Mr. Gore simply does not wish to participate in a financial wager.” Armstrong responded that it was fine by him and that we could “merely do it for its scientific value.” The spokesperson said that she would ask Mr. Gore. Armstrong asked if Mr. Gore would also respond to question #2.

The second question is of particular importance given that we have not been able to find any scientific forecasts to support global warming –or any that would support negative effects from global warming –or any to support the notion that efforts to reduce man-made CO2 would have a favorable impact on the climate. See Green & Armstrong’s paper “Global Warming: Forecasts By Scientists Versus Scientific Forecasts,” Energy & Environment 18 (2007), 995-1019.

Armstrong said that this is a scientific issue, not a political issue. Opinion polls do not provide a scientific approach in this situation, even when some of the respondents are climate experts. However, procedures do exist that would allow us to make scientific forecasts.

Meanwhile, Professor Armstrong awaits Mr. Gore’s response to the revised challenge.