Jf. Carrasco et Dh. Bromwich, A CASE-STUDY OF A MIDTROPOSPHERIC SUBSYNOPTIC-SCALE CYCLONE THAT DEVELOPED OVER THE ROSS SEA AND ROSS ICE SHELF OF ANTARCTICA, Antarctic science, 7(2), 1995, pp. 199-210
Satellite imagery, synoptic-scale analyses and automatic weather stati
on data were used to study a subsynoptic-scale cyclone that developed
over the Ross Sea and Ross Ice Shelf areas of Antarctica. A pre-existi
ng subsynoptic-scale midtropospheric cyclone descended from southern V
ictoria Land into the semi-permanent baroclinic environment over the s
outh-western corner of the Ross Sea. The subsynoptic-scale cyclone the
n developed into a frontal system travelling south-eastward over the R
oss Ice Shelf and decayed five days later over Marie Byrd Land. It is
concluded that stretching of the subsynoptic-scale low, while descendi
ng over 2000 m from the high plateau down to sea level, increased its
cyclonic vorticity via conservation of potential vorticity. This, alon
g with a cold katabatic outbreak into the northern part of the circula
tion, provided the mechanisms for its initial development. Subsequentl
y, cold boundary-layer air over the Ross Ice Shelf spiralled into the
subsynoptic-scale cyclone supporting its further development. An upper
-level synoptic-scale cyclone that approached the area provided the up
per-level support for its ESE displacement and development.