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An atmosphere-ocean regional climate model for the Mediterranean area:
Present climate and XXI scenario simulations
V. Artale, S. Calmanti, A. Carillo, A. Dell’Aquila, M. Herrmann, G. Pisacane, PM Ruti * and
G. Sannino, MV Struglia
ACS/CLIM-MOD, ENEA, Roma, Italy; paolo.ruti@enea.it
F. Giorgi, X. Bi, J.S. Pal and S. Rauscher
Abdus Salam ICTP,Trieste, Italy
In the framework of CIRCE EU Project, an atmosphereocean
regional climate model (AORCM) for the
Mediterranean basin, called the PROTHEUS system, is
presented. The PROTHEUS system is composed of the
regional climate model RegCM3 as atmospheric component
and a regional configuration of the MITgcm model as
oceanic component.
The model is applied to an area encompassing the
Mediterranean Sea and the adjacent basin (Fig. 1), where the
fine scale feedbacks associated with air-sea interactions can
substantially influence the spatial and temporal structure of
regional climate. We compare a 40-year simulation with the
PROTHEUS system driven by ERA40 reanalysis fields at
the lateral boundaries with a corresponding simulation
performed with the stand-alone configuration of the
atmospheric model RegCM3. We show that the coupled
system produces realistic features of atmospheric
circulations, land surface climate, ocean sea surface
temperature (SST), ocean surface circulations and air-sea
fluxes.
The main improvement associated with the use of the
coupled system is found by considering the high spatiotemporal
variability of surface fields. First, the coupled
model is able to capture the fine scale spatio-temporal
evolution of observed SST. Second, large changes in air-sea
fluxes are associated to the changes in SST and yield a better
simulation of fine temporal scale climate variability. Given
the successful development of the coupled model system
here described we envisage a number of possible
applications of the PROTHEUS system.
In this perspective, we have also performed a 1951-2050
scenario simulation driven by ECHAM5-MPIOM fields at
the lateral boundaries. Preliminary results from this run are
here shown.
Figure 1. Domain for: a) RegCM and b) MITgcm
with corresponding topography. Units are m.