Lew’s blog today on debunking CO2 global warming by using medieval data is important. I’ve found an article written by one of the co-authors of that scientific article. This article is quite readable, but that will depend on the training of the readers. Their entire paper is free here.
The artificial neural networks (ANN) method they use is a form of sophisticated curve-fitting and extrapolation. They “forecast what temperatures would have been in the absence of human-emission of carbon dioxide – for the last hundred years.”
“We figured that if we could apply the latest data mining techniques to mimic natural cycles of warming and cooling – specifically to forecast twentieth century temperatures in the absence of an industrial revolution – then the difference between the temperature profile forecast by the models, and actual temperatures would give an estimation of the human-contribution from industrialisation.”
“The average divergence between the proxy temperature record from this Northern Hemisphere composite, and the ANN projection for this period 1880 to 2000, is just 0.09 degree Celsius. This suggests that even if there had been no industrial revolution and burning of fossil fuels, there would have still been some warming through the twentieth century – to at least 1980.”
The blue line is an actual temperature series. The orange dotted line is what the ANN forecasted. Greater variation in actual data versus forecasted data is typical of forecasts.
2:14 pm on August 23, 2017
