The Global Warming Challenge

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Archive for the ‘media’ Category

Boxer and Armstrong Q&A

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The following is video of the Q&A portion of Examining Threats and Protections For the Polar Bear from January 30, 2008, between US Senator Barbara Boxer and Professor J. Scott Armstrong.

Written by climatebet

April 10, 2008 at 11:38 pm

Posted in media

Senator Inhofe: Global Warming Alarmism Reaches A “Tipping Point”

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October 26, 2007: Senator Inhofe addresses the Senate floor for two hours on the tipping point of climate alarmism (full text| video clip 1 | video clip 2). Scott Armstrong’s Global Warming Challenge to Al Gore, along with the Green and Armstrong’s global warming paper (2007) were both mentioned when citing challenges to climate model accuracy:

Internationally known forecasting pioneer Dr. Scott Armstrong of the Ivy League University of Pennsylvania’s Wharton School, challenged Gore to a $10,000 bet in June over the accuracy of climate computer models predictions. Armstrong and his colleague Professor Kesten Green of Monash University’s in Australia, found: “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.”

Written by climatebet

October 26, 2007 at 9:32 pm

Green and Armstrong Call for Scientific Forecasts of Sea Levels

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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 and request commentary at 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

Written by climatebet

September 27, 2007 at 5:43 am

Armstrong’s Congressional Briefing on YouTube

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Congressional Hearing 

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

Written by climatebet

September 16, 2007 at 5:12 am