TITLE:     Hydrographic variability of the waters overlying the West Antarctic
           Peninsula Continental Shelf
AUTHOR:    EE Hofmann, and JM Klinck
DATE:      9-13 February 1998
PLACE:     AGU/ASLO, Ocean Sciences Meeting, San Diego, CA

ABSTRACT:
  Hydrographic observations from four cruises between January 1993 and
February 1994 are used to provide the first description of variability in
temperature and salinity distributions on the west Antarctic Peninsula
continental shelf.  The largest variation is associated with Antarctic
Surface Water (AASW), which shows large temperature changes due to seasonal
heating and cooling but only small changes in salinity.  The Winter Water
(WW) portion of AASW is eroded during the austral summer and fall and
re-established in the austral winter.  The subpycnocline waters west of the
Antarctic Peninsula are composed of Modified Circumpolar Deep Water (MCDW),
which is a cooled version of the oceanic water mass Upper Circumpolar Deep
Water (UCDW).  MCDW does not undergo seasonal changes in properties.  Some
Lower Circumpolar Deep Water (LCDW) is found on the west Antarctic Peninsula
continental shelf, but its influence on subpycnocline waters is small. The
outer portion of the west Antarctic Peninsula continental shelf is influenced
by meandering of the Antarctic Circumpolar Current (ACC), which provides a
possible mechanism for episodic inputs of UCDW to the continental shelf.  If
true, then the subpycnocline waters on this continental shelf may be exchanged
at periodic intervals.  This across-shelf exchange appears to occur through
deep trenches that transect the shelf.