A sensitivity study to evaluate the greatest impact that sea-ice anoma
lies around Antarctica could have on the global atmospheric circulatio
n is conducted with the National Center for Atmospheric Research Commu
nity Climate Model, Version 2. A 15-year seasonal cycle simulation is
performed in which all sea ice around Antarctica is removed and replac
ed by year-round open water at -1.9 degrees C. The results are compare
d to a standard 15-year seasonal cycle run with boundary conditions se
t for the present climate. The comparison shows that substantial chang
es in pressure, vertical circulation, and precipitation are found in b
oth hemispheres as a result of Antarctic sea-ice removal. These anomal
ies are more significant in the southern hemisphere during May-Septemb
er, whereas the anomalies are more notable in the northern hemisphere
during September-November, a result which was not present in previous
perpetual simulations. Convective precipitation increases and large-sc
ale precipitation decreases as the circumpolar trough moves closer to
Antarctica in response to the sea-ice removal. Positive and negative a
nomalies form a wave-like train in the troposphere. The anomalies incl
ude the delayed onset of the winter monsoon over northern China during
September. This result is in basic agreement with an observational st
udy that found monsoon parameters are correlated with Antarctic sea-ic
e characteristics. In addition, the mean meridional circulation and co
nvective precipitation have a monthly modulation of roughly 5% in the
tropics. Mechanisms for the global atmospheric propagation of the impa
ct of the Southern Ocean surface heating anomalies are examined.