One of the main points of criticism of the CO2-dominated climate models is that they fail to reproduce the temperature fluctuations over the last 10,000 years.
This surprises no one as these models assign scant climate impact to major factors, i.e. the sun. As numerous IPCC-ignored studies show, the post-Ice Age temperature curve for the most part ran synchronously with solar activity fluctuations. The obvious discrepancy between modeled theory and measured reality has been brought up time and again.
The journal Climate of the Past Discussions has published a new paper written by a team led by Gerrit Lohmann of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. The group compared geologically reconstructed ocean-temperature data over the last 6000 years to results from modeling. If the models were indeed reliable, as is often claimed, then there would be good agreement. Unfortunately in Lohmann’s case, agreement was non-existent.
Lohmann et al plotted the geologically reconstructed temperatures and compared them to modeled temperature curves from the ECHO-G Model. What did they find? The modeled trends underestimated the geologically reconstructed temperature trend by a factor of two to five. Other scientists have come up with similar results (e.g. Lorenz et al. 2006, Brewer et al. 2007, Schneider et al. 2010).
The comprehensive temperature data collection of the Lohmann team distinctly shows the characteristic millennial scale temperature cycle for many regions investigated, see Figure 1 below. Temperatures fluctuated rhythmically over a range of one to three degrees Celsius. In many cases these are suspected to be solar-synchronous cycles, like the ones American Gerard Bond successfully showed using sediment cores from the North Atlantic more than 10 years ago. And here’s an even more astonishing observation: In more than half of the regions investigated, temperatures have actually fallen over the last 6000 years.