This morning, there was lot of noise in the Dutch media (unfortunately in Dutch only) about new research that was claiming a dramatic warming of 4 degrees in 2050. The news report quoted Dutch econometricians from the University of Tilburg. They had done a statistical analysis of temperature data and the influence of CO2 and solar radiation and concluded that aerosols masked much more of the warming of greenhouse gases than previously thought. This also means there is more warming in the pipeline for the future if the trend of global brightening, that has been detected by researcher Martin Wild of ETH in Zürich, will continue in the coming decades. They also draw policy conclusions from their research stating that in order to avoid more than 2 degree warming more drastic measures are to be taken. This news was copied by many Dutch news outlets.
Science has spoken. We need to stop questioning at this point, and all turn in our SUV’s
But, in order to get their results, the scientists used a certain database from CRU, called “CRU TS 2.0”
And the documentation to that database says:
Q1. Is it legitimate to use CRU TS 2.0 to ‘detect anthropogenic climate change’ (IPCC language)?
CRU TS 2.0 is specifically NOT designed for climate change detection or attribution in the classic IPCC sense. The classic IPCC detection issue deals with the distinctly anthropogenic climate changes we are already experiencing. Therefore it is necessary, for IPCC detection to work, to remove all influences of urban development or land use change on the station data.
In contrast, the primary purpose for which CRU TS 2.0 has been constructed is to permit environmental modellers to incorporate into their models as accurate a representation as possible of month-to-month climate variations, as experienced in the recent past. Therefore influences from urban development or land use change remain an integral part of the data-set. We emphasise that we use all available climate data.
If you want to examine the detection of anthropogenic climate change, we recommend that you use the Jones temperature data-set.