Monthly Archives: June 2010

Consensus in precipitation projections

In the AR4, the IPCC presented this figure showing the consensus in precipitation projections for the 21st century, designed to be of use to planning for adaptation and mitigation. The coloured regions show where changes are likely to occur. My … Continue reading

Posted in GCMs, precipitation, projections, variability | 2 Comments

Global mean temperature variability in observations and GCMs

I am often surprised at how different climate models can be. Shown below is the annual mean, global mean surface air temperature from control runs of 21 of the AR4 GCMs, along with the observations (HadCRUT3). The spread in the magnitude of variability is enormous, as seen by eye, but also the timeseries have very different ‘memory’ characteristics. Continue reading

Posted in GCMs, temperature, variability | 7 Comments