Including the Stratosphere in Models of Global Climate Change
Marsh, D.R., Mills, M.J., Kinnison, D.E., Lamarque, J.-F., Calvo, N., and Polvani, L.M. 2013. Climate change from 1850 to 2005 simulated in CESM1(WACCM). Journal of Climate 26: 7372-7391.
The six scientists report that "in comparison of tropospheric climate predictions with those from a version of CESM that does not fully resolve the stratosphere, the global-mean temperature trends are indistinguishable," which suggests no improvement in the new model over the old model. However, they state "systematic differences do exist in other climate variables, particularly in the extratropics." And they state "the magnitude of the difference can be as large as the climate change response itself."
Marsh et al. additionally report "both models overestimate the short-term cooling following large volcanic eruptions." And they note "WACCM predicts significantly larger changes in precipitation over Europe, the Mediterranean, and northern Africa," once again stating "the differences in predicted changes between the two models can be larger than the magnitude of the climate change prediction itself." And in regard to this unsettling fact that keeps popping up, they conclude, "when quantifying uncertainty in past and future climate change predictions, it will be important to consider the systematic errors introduced by the choices made on how the upper atmosphere is represented in the model," which suggests the quest for the Holy Grail of climate modeling has yet to be satisfactorily consummated.