Chapter 7
The Simulation of
Weather Types in GCMs:
A Regional Approach to
Control-Run Validation
by Keith R. Briffa
7.1 Introduction
General Cireulation Models (GCMs) attempt to reproduce the threedimensional atmospheric processes whieh result in the surfaee climate that
we experience aeross different regions of the globe. The time and spatial
seales upon which various GCMs operate are mueh eruder (less-well resolved)
than those of the real world. Nevertheless, GCM experiments offer the most
promising approach for gaining insight into the physieal meehanisms underlying past and potential future climates, partieularly at a regional level. It is
this regional detail which is needed to develop and test theories about past
climates and for making predictions about future climates that might eome
about as a eonsequenee of inereasing greenhouse gases.
It should be self evident that there is a need to establish how weIl partieular GCMs suceeed in reproducing modern-day climates (i.e. the accuraey
of eontrol-run simulations). This information represents important diagnosAcknowledgements: The work describedhere was funded by the U.K. Dept. Environment under grant PECD/7/12/78.
The Simulation of
Weather Types in GCMs:
A Regional Approach to
Control-Run Validation
by Keith R. Briffa
7.1 Introduction
General Cireulation Models (GCMs) attempt to reproduce the threedimensional atmospheric processes whieh result in the surfaee climate that
we experience aeross different regions of the globe. The time and spatial
seales upon which various GCMs operate are mueh eruder (less-well resolved)
than those of the real world. Nevertheless, GCM experiments offer the most
promising approach for gaining insight into the physieal meehanisms underlying past and potential future climates, partieularly at a regional level. It is
this regional detail which is needed to develop and test theories about past
climates and for making predictions about future climates that might eome
about as a eonsequenee of inereasing greenhouse gases.
It should be self evident that there is a need to establish how weIl partieular GCMs suceeed in reproducing modern-day climates (i.e. the accuraey
of eontrol-run simulations). This information represents important diagnosAcknowledgements: The work describedhere was funded by the U.K. Dept. Environment under grant PECD/7/12/78.