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Tropical Upper Tropospheric Warming: Models vs. Measurements
Reference
Po-Chedley, S. and Fu, Q. 2012. Discrepancies in tropical upper tropospheric warming between atmospheric circulation models and satellites. Environmental Research Letters 7: 10.1088/1748-9326/7/4/044018.

Background
The authors write that "recent studies of temperature trend amplification in the tropical upper troposphere relative to the lower-middle troposphere found that coupled atmosphere-ocean models from CMIP3 exaggerated this amplification compared to satellite microwave sounding unit (Fu et al., 2011) and radiosonde (Seidel et al., 2012) observations."

What was done
Po-Chedley and Fu, as they describe it, "revisit this issue using atmospheric GCMs [global circulation models] with prescribed historical sea surface temperatures (SSTs) and coupled atmosphere-ocean GCMs that participated in the latest model intercomparison project, CMIP5."

What was learned
The two researchers say their work demonstrated that "even with historical SSTs as a boundary condition, most atmospheric models exhibit excessive tropical upper tropospheric warming relative to the lower-middle troposphere as compared with satellite-borne microwave sounding unit measurements." In addition, they say that "the results from CMIP5 coupled atmosphere-ocean GCMs are similar to findings from CMIP3 coupled GCMs."

What it means
Once again we have numerous climate model results that deviate significantly from real-world measurements; and we see no improvement in this regard between the CMIP3 set of models and the newer and supposedly improved CMIP5 models. This is not what most rational people would call progress.

References
Fu, Q., Manabe, S. and Johanson, C.M. 2011. On the warming in the tropical upper troposphere: models versus observations. Geophysical Research Letters 38: 10.1029/2011GL048101.

Seidel, D.J., Free, M. and Wang, J.S. 2012. Reexamining the warming in the tropical upper troposphere: models versus radiosonde observations. Geophysical Research Letters 39: 10.1029/2012GL053850.

Reviewed 15 May 2013