Al Gore Blows a Deadline

Published March 28, 2008

Al Gore, one of the world’s leading proponents of the crisis theory of global warming, missed a deadline Thursday to set up a debate with a leading expert on forecasting to test the crisis theory.

Scott Armstrong, a professor at the Wharton School at the University of Pennsylvania, issued the Global Warming Challenge to the former Vice President last June.

Gore initially indicated interest in the challenge, but he expressed some concerns.

Armstrong asserted that over the next 10 years he could forecast temperature change more accurately than any climate model that Gore might nominate. Armstrong’s forecast would be that the global mean temperature would not change over the 10 years. It is the so-called “naive model” that has been shown by prior research to be appropriate for complex situations with high uncertainty.

Armstrong proposed each man would put $10,000 into a charitable trust fund, and the one with the most accurate forecast would designate a recipient.

Gore was busy when the issue was first raised, so Armstrong extended the deadline to March 26 for a response and also simplified the bet so Gore merely needed to put a check beside a climate model that would produce forecasts for him. Gore then came back and said he did not believe in money wagers — so Armstrong proposed that they forget the money and just conduct the challenge for scientific purposes

Nothing more was heard from Gore and the deadline passed.

On March 28, Dr. Armstrong then asked Mr. Gore, “When and under what conditions would you be willing to engage in a scientific test of your forecasts?”

Armstrong said, “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 It includes all correspondence between Scott Armstrong and Al Gore.

For more information: Prof. Scott Armstrong 610/622-6480.

Dan Miller, executive vice president and publisher, The Heartland Institute: weekend phone 773/764-5367.

Armstrong was a speaker at the 2008 International Conference on Climate Change, which attracted more than 500 scientists, economists, and policy analysts to New York City March 2-4, 2008. For more information and audio from the conference, visit