TITLE:   Palmer LTER: Temporal and Spatial Variability of Dissolved Inorganic
         Carbon, Oxygen Saturation and Partial Pressure of Carbon Dioxide in
         Surface Waters West of the Antarctic Peninsula

AUTHORS: Christopher J.  Carrillo, David M. Karl
DATE:    2-4 August 2000
PLACE:   LTER All Scientists Meeting 2000, Long-Term Ecological Research:
	 Unifying Principles & Global Applications, Snowbird, Utah
         
         University of Hawaii, Honolulu, HI. 96822 
	 Poster - Session: Aquatic Studies/Hydrologoy/Geomorphology (F05)

ABSTRACT

Chemical, physical and biological controls on in-situ dissolved inorganic
carbon (DIC) concentrations, oxygen (O2) saturation and fugacity of carbon
dioxide (fCO2) in surface water induce temporal and spatial habitat
variability. The Pal-LTER Program was established in 1990 to study the
Antarctic marine ecosystem in the area west of the Antarctic
Peninsula.  Our component of this multi-disciplinary project includes
measurements of C and O inventories (dissolved gases and solutes), C and O
fluxes (production, particle export and air-to-sea gas exchange) and
microbial community structure and function. This poster summarizes one
aspect of this broader set of research objectives. Dissolved inorganic
carbon, O2 and fCO2 show large interannual and spatial variability
throughout the region. Surface water measurements of fCO2 showed large
onshore to offshore gradients relative to interannual variations. Areas of
undersaturation (values below atmospheric) occured in coastal waters and
were associated with increases in chlorophyll, implying a biological
control. The magnitude and timing of sea-ice throughout the LTER region
and fluctuations in the amount of Antarctic Circumpolar Water upwelled
onto the shelf may explain the interannual and spatial variability shown
here.