Five-year seasonal cycle output produced by the NCAR Community Climate
Model Version 1 (CCM1) with R15 resolution is used to evaluate the ab
ility of the model to simulate the present-day climate of Antarctica.
The model results are compared with observed horizontal syntheses and
point data. Katabatic winds, surface temperatures over the continent,
the circumpolar trough, the vertical motion field, the split jet strea
m over the Pacific Ocean, and the snowfall accumulation are analyzed.
The results show that the CCM1 with R15 resolution can well simulate t
o some extent the dynamics of Antarctic climate not only for the synop
tic scale, but also for some mesoscale features (mesoscale cyclogenesi
s). This is reflected in the zonal-mean pattern of vertical motion by
the presence of two convergence centers. The finding suggests that the
CCM1 might also capture the split jet stream over New Zealand in wint
er, but the evidence is mixed. This is inferred to be due to inadequat
e simulation of the thermal forcing over high southern latitudes. The
CCM1 can also capture the phase and amplitude of the annual and semian
nual variation of temperature, sea level pressure, and zonally average
d zonal (E-W) wind. That the CCM1 can simulate some characteristics of
the semiannual variation may be due to the improved radiation treatme
nt compared to the earlier CCM0. The most dramatic shortcomings were a
ssociated with the model's anomalously large precipitation amounts at
high latitudes, which result from the scheme to suppress negative mois
ture values. The simulations of cloudiness and the atmospheric heat ba
lance are adversely affected. A greatly refined moisture budget scheme
is needed to eliminate these problems and may allow the split jet-str
eam feature over the New Zealand area in winter to be accurately repro
duced. A coupled mesoscale-CCM1 model may be needed to adequately simu
late the feedback from mesoscale cyclones to synoptic-scale weather sy
stems, and the katabatic wind circulation.