Archive for the ‘j scott armstrong’ Category
With October 2013′s global mean temperature data in, we now have 70 months of evidence on the accuracy of Mr Gore and the IPCC’s alarming warming forecast of temperatures increasing at a rate of 0.03ºC per annum. If Mr Gore’s forecast were valid and unbiased, we would expect actual temperatures to be higher than his forecast roughly half of the time and lower roughly half of the time. We checked the record of The Bet. It turns out that, to date, the actual global mean temperature has been higher than Mr Gore’s forecast less than one-quarter (23%) of the time. By contrast, the measured temperature has been warmer than the no-change benchmark, Professor Armstrong’s bet, 46% percent of the time; very close to the ideal of 50%. The updated chart is to the right.
“There are no scientific forecasts of dangerous global warming” shouts a new article in the Financial Post. Readers of this blog know that already, but will likely want to read what the op-ed titled “Climate forecast: All’s well, despite what the IPCC says” by Kesten Green, Scott Armstrong, and Willie Soon has to say about the implications for government policy. It has already attracted lively discussion. The article is here.
The authors claim to provide the only scientific forecast of long-term climate, namely the naive no-change or no-trend forecast that is the basis of Professor Armstrong’s notional bet with Mr Gore. The forecast was originally published in 2009, and the International Journal of Forecasting article can be found here. The authors’ current working paper investigating possible improvements to climate forecasting for policy makers is here.
The September global temperature anomaly was the highest it’s been since January, and is close to Mr Gore’s “forecast” for the month. The balance of the bet remains firmly in Professor Armstrong’s favour, however: The error of the red-hot alarmist projection is to date nearly 20% higher than the error from the scientific cool-green no-trend forecast. See the updated chart (color coded) and table to the right.
The Nongovernmental International Panel on Climate Change (NIPCC) has released a new report on the science of climate change: Climate Change Reconsidered II: Physical Science. The key takeaway messages are (1) the human impact on climate is very small and (2) any change in temperatures that might be occurring or will occur in the future is so small that it will not be noticed against the climate’s entirely natural variability.
As part of the NIPCC’s process for preparing this volume, scores of scientists from around the world evaluated the most up-to-date research on the physical science of climate change. This report is at least as comprehensive and authoritative as the reports of the United Nations-funded Intergovernmental Panel on Climate Change (IPCC) … and the NIPCC report is faithful to the scientific method. Whereas the mission of the IPCC is to find a human impact on climate change and thus justify government control of greenhouse gas emissions and our economy, the NIPCC has no agenda other than discovering the truth about climate change.
Section 1.1.1 of the report addresses forecasting principles and methods, and was co-authored by J Scott Armstrong and Kesten C Green. It is on p.14 of the Chapter 1 of the report, which is available here.
At 0.16°C, the August 2013 global average temperature anomaly is again below the no-change forecast of 0.208°C. For the 68 months of the bet now behind us, the average temperature has been equal to or below the no-change forecasts for 38 months or 56% of the time. For the latest data and chart on the Armstrong-Gore climate bet, click on the updated chart in the column to the right.
The Doctors for Disaster Preparedness Conference in Houston (July 12 to 15 2013) featured several talks related to the dangerous manmade global warming alarm, including one from theclimatebet.com’s Professor Scott Armstrong. A video of his talk, “Evidence-Based Forecasting for Global Warming”, is available here. Willie Soon’s talk, “Five or more failed experiments in measuring global sea level change”, is available here, and Antony Watts’s talk, “Ten tests to determine whether you should be concerned about global warming” is available here.
Scott Armstrong and Willie Soon both spoke on long-term climate forecasting—Armstrong on temperatures and Soon on sea levels—on 13 and 14 July 2014 at the Doctors for Disaster Preparedness Meeting in Houston, Texas. Scott Armstrong’s talk was titled “Evidence-based forecasting for global warming” and the slides are available here. Willie Soon’s talk was titled “Five or more failed experiments in measuring global sea level change” and a video recording of it is available, here.
Both scientists describe how alarming forecasts have been derived for these poorly understood situations using complex mathematical models with many variables and judgmental adjustments. These procedures violate The Golden Rule of Forecasting, which requires forecasters to be conservative, especially in the presence of great uncertainty.
We have belatedly updated the Armstrong-Gore bet graph, to the right. Those of you with keen eyes and good memories may notice some differences in the plot of the temperature series. The UAH global mean temperature anomaly series has been revised to Version 5.6. Information about the revision is available here.
With the release of the June figure, for the second time in 2013 Al Gore’s putative global mean temperature forecast was more accurate than the no-change forecast, .005°C more accurate.
The May 2013 data has been released and shows the monthly temperature anomaly was below the 2007 average that is the starting point of the Armstrong-Gore graph for the fourth month running. So far, the total error of Mr Gore’s warming forecast is 21% larger than the error of Professor Armstrong’s no-change forecast. See the updated Climate Bet graph at right for the details.
It occurred to us that the bet would have been fairer to Mr Gore and the IPCC if we had used the data that were available to Mr Gore when he released his movie “An Inconvenient Truth”, during 2006, as the base-year for The Bet. (The base year that we use for The Bet, 2007, was the most recent data available when Professor Armstrong issued his challenge to Mr Gore.) And so we re-ran The Bet using the 2005 average (the latest full year available to Mr Gore when he released his movie) as the base year. Mr Gore’s forecast in the re-run is for a 0.03ºC p.a. increase from the 2005 average and Professor Armstrong’s is simply the 2005 average.
In the event, re-running The Bet from 2008 to date using 2005 as a base results in a total error for the Gore/IPCC alarming warming forecast that is 31% larger than the error of the no-change forecast. We think Mr Gore would likely prefer to stick with the current Bet arrangement, even though it is not as fair.
After spiking in January, temperatures in April were again well below the 2007 average that is Scott Armstrong’s forecast. (See the updated chart to the right for the state of the bet.) Over the duration of the 64 months to date of the bet, temperatures have been greater than Mr Gore’s IPCC-based warming forecast for 15 months or less than 23% of the time. In contrast, temperatures have been less than Professor Armstrong’s evidence-based forecasts for 36 months or more than 56% of the time. None of the forecasts was exactly equal to the actual temperature. The results support the contention that Mr Gore and the IPCC’s dangerous warming forecasts are insufficiently conservative given the state of knowledge about climate, and that the Green, Armstrong, and Soon (2009) no-change model provides a better representation of the considerable uncertainty that exists.