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Modeling Precipitation Over the Mediterranean Region
Barkhordarian, A., von Storch, H. and Bhend, J. 2013. The expectation of future precipitation change over the Mediterranean region is different from what we observe. Climate Dynamics 40: 225-244.

It is always good to compare one's expectations of something with real-world situations where that something might be expected to occur; and that is what the authors of a new paper published in Climate Dynamics have done, examining "to what extent the present climate change 'is on the way' towards conditions described by the climate change scenarios at the end of this century."

What was done
According to Barkhordarian et al., they assessed the role of anthropogenic forcing - due to greenhouse gases and sulphate aerosols (GS) - in recently observed precipitation trends over the Mediterranean region in order to determine if the observed trends over the period 1966-2005 (over land) and 1979-2008 (over land and sea) "are consistent with what 22 models project as response of precipitation to GS forcing," where "significance is estimated using 9,000-year control runs derived from the CMIP3 archive."

What was learned
The three researchers discovered that "the observed trends are markedly inconsistent with expected changes due to GS forcing," noting that "observed changes are several times larger than the projected response to GS forcing in the models." But they indicate that "the most striking inconsistency" was "the contradiction between projected drying and the observed increase in precipitation in late summer and autumn."

What it means
Coming to a conclusion that simply could not be avoided, Barkhordarian et al. state that "the detection of an outright sign mismatch of observed and projected trends in autumn and late summer, leads us to conclude that the recently observed trends cannot be used as an illustration of plausible future expected change in the Mediterranean region," once again illustrating the folly of placing too much faith in even the best of climate model projections.

Reviewed 22 May 2013