By now most German readers here know the excellent site by global warming science skeptics Dr. Sebastian Lüning and Prof. Fritz Vahrenholt. The two authored the book “Die kalte Sonne“, which upset the German climate science establishment. The book is also available in English under the title: The Neglected Sun.
At their Die kalte Sonne site the pair has, as usual, another outstanding post on global warming and on how it has so far been totally exaggerated.
Global Temperature Rise Far Below “Most Probable” Model Projection
By Dr. Sebastian Lüning and Prof. Fritz Vahrenholt
(Translated/edited by P Gosselin)
Who doesn’t like looking through old books? Recently “Die kalte Sonne” chief editor Sebastian Lüning picked out from his living room bookshelf a copy of Klimaänderungen by Christian Schönwiese, which was published by Springer Verlag in 1995:
In English the title of the book by Christian Schönwiese reads “Climate Change: Data, Analyses, Prognoses”.
Flipping through the pages one comes across a figure depicting the projected temperature rise by 2100 (page 179, Fig. 54). How did scientiosts back then estimate the temperature development in the year the second IPCC report was released? Shown in the following figure are three estimates: a high estimate (if things really get serious), a best estimate (most probable warming) and a low estimate (if the climate danger is not as bad as feared).
Figure 1: Temperature prognosis up to 2100. From: Schönwiese 1995.
Some 20 years later we are now able to look back and check to see just how well the predictions are turning out. Is the prediction right, wrong, or perhaps not even close?
We’ve taken the liberty of superimpsing on the 1995 – 2015 measured temperature curve to the above chart. To do this we used the global HadCRUT-data series. Quick and dirty, Figure 2 shows the result with the added 20 years of data.
Has nature followed along the projection? The real temperatures are actually slightly below the low estimate:
Figure 2: Temperature prognoses by Schönwiese, 1995, with superimposed temperature plot of HadCRUT 1995-2015 series (red). Chart of temperature vs time. “Schon eingetreten” – already measured; “Beobachtung” – observed; “hohe Schätzung” – high estimate; “Bestschätzung” – best estimate; “niedrige Schätzung” – low estimate.
So what could this possibly mean? According to the IPCC reports, the ‘transient’ short term TCR climate sensitivity is somewhere between 1.0-2.5°C warming for each doubling of CO2 concentration (Figure 3). That translates to a long-term ECS Climate Sensitivity of 1.5-4.5°C. Obviously the real temperature trend is currently below the lowest scenario.
Using the IPCC range, everything is pointing to a CO2 climate sensitivity of 1.0°C (TCR) or 1.5°C (ECR). Of course this is nowhere mentioned in the latest IPCC report. In the meantime curves and data have been shifted about, jerked around, and distorted so that the original prognoses over the years can be propped up. Of course none of it makes sense, but that is just the way it is. Complaints aren’t going to help. As the old saying goes: The one in charge is the one who is pulling the strings.
Figure 3: Overview of the IPCC reports for climate sensitivity. From Lewis & Crok (2014).