The Global Warming Challenge

On January 30, 2008, Scott Armstrong gave a talk presenting his findings to the US Senate Committee on Environment and Public Works’ “Examining Threats and Protections for the Polar Bear”. Click here for full text of the talk. The following are selected excerpts. Full text is available of the paper “Polar Bear Population Forecasts: A Public Policy Forecasting Audit” by Armstrong, Green, and Soon.

We conducted forecasting audits of two of the nine administrative reports that were prepared in 2007 to “…Support U.S. Fish and Wildlife Service Polar Bear Listing Decision.” We selected the reports Amstrup et al. and Hunter et al. as they appeared to be the primary forecasting documents. Our concern was to establish whether the reports’ forecasts of the polar bear population over the balance of the 21st Century were the product of scientific procedures.
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By TOM KIZZIA (tkizzia@adn.com)

The following are some excerpts from the article discussing Alaska’s decision whether to list polar bears as endangered or not. Click here for the full text available online.

Ken Taylor has had easier jobs than this one. It’s not like the good old days chasing rhinos, climbing into bear dens and wrestling beluga whales in shallow water.

These days, sitting at a desk as deputy commissioner of fish and game, the veteran wildlife biologist has to muster the best science he can find to argue that Alaska’s polar bears are in good shape and need no special protection from hypothetical doomsday scenarios.

This requires Taylor to stand up to the prevailing wisdom about global warming in most of the world’s scientific community and the public — not to mention some pretty strong opinions in his own department.

But Taylor, the Palin administration’s point man on polar bears, argues that the scientific justification simply isn’t there — at least not yet — to declare the polar bear “threatened” and touch off a cascade of effects under the Endangered Species Act. A decision on the bears is expected from the U.S. Department of the Interior in the next few weeks.

“From my perspective, it’s very difficult to put a population on the list that’s healthy, based on a projection 45 years into the future,” Taylor says. “That’s really stretching scientific credibility.”

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The state also pokes at studies used to predict the future of polar ice, quoting at length from the climate scientists’ own demurrals about margins of error. The chain of predicted problems following from those studies are based on “unsupported conjecture,” the state says.

The state’s critique was based on the work of a consultant, J. Scott Armstrong, a University of Pennsylvania expert on mathematical forecasting who has elsewhere challenged former vice president Al Gore to a $10,000 bet on whether the globe is truly warming.

Scott Armstrong and Kesten Green are two of the over 400 prominent scientists featured in a Senate Report debunking the scientific “consensus” on global warming. The report was released December 20th, 2007, and can be accessed at the U.S. Senate Committee on Environment & Public Works site. The following is a selected excerpt citing Armstrong’s climate challenge to Al Gore, scientific forecasts versus forecasts by scientists, and the recent study of polar bear prediction methodology.

Internationally known forecasting pioneer Dr. Scott Armstrong of the Wharton School at the Ivy League University of Pennsylvania and his colleague Kesten Green of Monash University in Australia challenged Gore to a $10,000 bet in June 2007 over the accuracy of climate computer models predictions. “Claims that the Earth will get warmer have no more credence than saying that it will get colder.” According to Armstrong, the author of Long-Range Forecasting, the most frequently cited book on forecasting methods, “Of 89 principles [of forecasting], the [UN] IPCC violated 72.” Armstrong and Green also critiqued the Associated Press for hyping climate fears in 2007. “Dire consequences have been predicted to arise from warming of the Earth in coming decades of the 21st century. Enormous sea level rise is one of the more dramatic forecasts. According to the AP’s Borenstein, such sea-level forecasts were experts’ judgments on what will happen,” Armstrong and Green wrote to EPW on September 23, 2007.

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After a series of cordial exchanges, Al Gore had said that he was too busy when the challenge was first offered. As a result, Scott Armstrong extended the deadline and simplified the process such that the only actions required of Al Gore are to 1) sign the letter and 2) deposit $10,000 in the Challenge Fund. The letter below explains the new simplified process.

November 28, 2007

Honorable Albert Gore
2100 West End Avenue
Suite 620
Nashville, TN 37203

Dear Mr. Gore,

Thank you for your previous emails and your letter concerning the Global Warming Challenge. You had mentioned that you were looking forward to reading my book, Principles of Forecasting; I believe the principles are critical to making accurate forecasts for global warming.

In earlier communications, your staff mentioned that you were too busy at the time to enter in the Global Warming Challenge. As a result, I am happy to extend the deadline beyond December 1st, 2007, to March 26th, 2008. In addition, I have found a way to make your task much easier. I propose that you place $10,000 on the Hadley Centre Forecasts.

This would merely require that you sign on the “I agree” line at the bottom of this letter. Each of us would then arrange to transfer $10,000 to a trust of your choosing. The money would be invested in mutual funds, and the proceeds would go to the winner’s charity on March 26th, 2018.

As a brief reminder, here is an overview of the original Global Warming Challenge (details can be found at http://theclimatebet.com):

Al Gore is invited to select any currently available fully disclosed climate model to produce the forecasts (without human adjustments to the model’s forecasts). Scott Armstrong’s forecasts will be based on the naive (no-change) model; that is, for each of the ten years of the challenge, he will use the most recent year’s average temperature at each station as the forecast for each of the years in the future.

Details on the 10-year bet would be handled with discussions between me the Hadley Centre. I would ask an independent board to aid in this process of finding an appropriate design and to monitor the progress of the bet. You would be kept up to date, and you would have the right to ask the board to consider changing aspects of the design.

In The Assault on Reason, you stated your interest in the use of science in addressing global warming:

“We must, for example, 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. Americans in both parties should insist on the reestablishment of respect for the rule of reason. The climate crisis, in particular, could cause us to reject and transcend ideologically based distortions of the best available scientific evidence.” p. 10

I believe we have a common goal. Although I expect to win, the purpose of the challenge is to promote interest in a scientific approach to forecasting. Climate experts have done much useful work to explain the past, but their approach to forecasting does not adhere to scientific principles.

Sincerely,

J. Scott Armstrong

For the signature of Mr. Gore:

____________________________________________
I agree to the terms of the Global Warming Challenge with the variations specified in this letter

Dire consequences have been predicted to arise from the warming of the Earth in coming decades of the 21st Century. Enormous rises in sea level represent one of the more dramatic forecasts. A recent article provided sea-level forecasts based on experts’ judgments of what will happen. These judgments are in turn based on experts’ predictions of global warming. The article made no reference to scientific forecasts. As shown in Green and Armstrong (2007) experts’ forecasts have no validity in situations characterized by high complexity, high uncertainty, and poor feedback. Numerous other scientists also criticized this approach.

To date we are unaware of any forecasts of sea levels that adhere to proper (scientific) forecasting methodology and our quick search on Google Scholar came up short. If such forecasts are available, please provide citations and support as to their validity. As a first step, it would be useful to summarize studies that extrapolate long-term trends; this summary could provide a benchmark for comparison with other studies.

We will provide free access to them at publicpolicyforecasting.com and request commentary at theclimatebet.com. Media outlets should be clear when they are reporting on scientific work and when they are reporting on the opinions held by some scientists. Without scientific support for their forecasting methods, the concerns of scientists should not be used as a basis for public policy.

Kesten Green and Scott Armstrong

In the Australian Financial Review (September 8, 2007), Mark Lawson’s article, “Global warming sceptics fuel hot debate” features Dr. Green, and highlights the Green and Armstrong paper. The following is an excerpt:

Global warming sceptics fuel hot debate
(Click here for full text)

Mark Lawson

“Despite being scorned, derided and accused of links with oil companies, the climate change sceptics are still out there and, although the greenhouse lobby will never admit it, occasionally scoring major points. They may also be more numerous than the greenhouse lobby or politicians believe…

A much more serious, if not devastating, attack on greenhouse claims concerning likely future temperature increases was the recent release of a paper entitled Global Warming: Forecasts by Scientists versus Scientific Forecasts.

Written by J. Scott Armstrong, a professor of marketing at The Wharton School, University of Pennsylvania, and Kesten Green, a visiting fellow at the business and economics forecasting unit at Monash University in Melbourne, the paper assessed, as forecasts, the temperature projections made by the Intergovernmental Panel on Climate Change earlier this year. It found little to approve.”

A Congressional Briefing about forecasts of global warming given by Scott Armstrong on Thursday, Sept 13 is now available on YouTube (Part 2 and Part 3). The briefing was based on the Green & Armstrong paper, “Global Warming: Scientific Forecasts or Forecasts by Scientists?” The global warming paper is the first of what they hope will be many forecasting audits of global warming studies to be presented on the new Special Interest Group page at http://publicpolicyforecasting.com.

Although climate scientists have extensive climate knowledge and are aided by computer models, their long-term forecasts are essentially their judgments of what will happen in the decades to come. Unstructured judgments are used to determine the structure and much of the content of climate models. Unstructured judgments are also used to accept or reject model outputs.

Green and Armstrong (2007) found that climate modelers do not use evidence-based principles to forecast. In fact, they violate many principles of forecasting.

One solution to this problem is to combine what is known about forecasting methods with what climate scientists know. Knowledge about forecasting is provided at http://forecastingprinciples.com. In addition, the site lists many experts in forecasting methods who are available as consultants.

Armstrong and Green’s work was featured in the Sydney Morning Herald’s July 7, 2007 article, “Chorus does not justify climate prophecies” by Michael Duffy:

The next week promises some excitement for those who believe global warming threatens our future. Today they can enjoy the Live Earth concert in Sydney. But on Thursday they will have to suffer ABC TV’s showing of The Great Global Warming Swindle, a British documentary sceptical of the orthodoxy…

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Click here for the audio of the interview. Click “Listen now” and move the slider to about 34 minutes to hear the relevant clip.

Making predictions is a difficult business, Dr Kesten Green an expert in the field, says that many scientists when looking at the future impact and extent of climate change fail to take into account the basic principles of forecasting.    

Counterpoint is a program on the Radio National Network of the Australian Broadcasting Corporation, presented by Michael Duffy and Paul Comrie-Thompson.