Gardner, W. D.. TAMU, wgardner@ocean.tamu.edu
Richardson, M. D.. TAMU, mrichardson@ocean.tamu.edu
Walsh, I. D.. OSU, walsh@oce.orst.edu
Smith, W. O.. VIMS, wos@vims.edu

 
POC DISTRIBUTIONS AND PHYSICAL FORCING IN THE ANTARCTIC POLAR FRONT ZONE
 
The objective of the Antarctic Environment and Southern Ocean Process Study (AESOPS) was to characterize the biogeochemical processes between 53 S and the ice edge. Hydrographic sections and 2-day process stations were made from north of the Antarctic Polar Front Zone (APFZ) to the pack ice edge along 170 W to explore POC/particle dynamics in relationship to production and export flux. Seasonal and spatial changes in POC and chlorophyll were measured by calibrating continuous measurements with a transmissometer and a fluorometer with discrete measurements of POC and chlorophyll from bottle samples. A phytoplankton bloom appeared to advance southward from November to February with the melting of ice to 65 S with little influence from the position of the APFZ. In early February the ice rapidly retreated to 74 S, opening a vast expanse of water where the bloom was patchy rather than spreading uniformly southward. By early March, no bloom conditions could be found even as far south as 71.3 S. Some waters appeared never to have experienced a bloom during this season. There appeared to be plenty of light and nutrients in February/March, so a major unanswered question is what caused the bloom to die out?
 
Day: Thursday, Feb. 4
Time: 03:30 - 03:45pm
Location: Sweeney Center
 
Code: SS31TH0330S