TITLE:   Long-Term Ecological Research (LTER) program: Underway
         semi-continuous measurements of surface ocean CO2 concentrations
AUTHORS: CJ Carrillo and DM Karl
DATE:    1997 
Palmer LTER Contribution No. xxx
Antarctic Journal  of the United States, (submitted)

Abstract - 
Accurate estimation of carbon dioxide (CO2) fluxes, coupled with an
understanding of the processes that control these fluxes, is necessary to
predict future CO2 concentrations in the Southern Ocean.  The chemical,
physical and biological controls on in situ CO2 concentrations cause habitat
variability both temporally and spatially.  Open ocean areas presently have
high nutrient concentrations but low standing stocks of phytoplankton and low
rates of primary production.  In sharp contrast to the high nutrient, low
productivity open ocean areas, coastal regions of Antarctica exposed to the
annual advance and retreat of sea ice, sustain seasonal phytoplankton blooms
with high rates of primary  production (Smith and Nelson 1985; Holm-Hansen et
al. 1989).  Consequently, coastal and ice-edge regions of Antarctica could
potentially remove atmospheric CO2, but these local sinks may be offset by
equally large sources of CO2 during winter periods of net heterotrophy or as a
result of the upwelling of CO2-enriched waters.  The seasonal advance of the
ice in the fall and retreat in the spring may also affect the flux of CO2 in
ice-dominated Southern and Arctic Oceans.  Quantifying these fluxes will
require sampling in the dissimilar ecosystems that make up the Southern Ocean.
The Palmer Long-Term Ecological Research (LTER) Program was established in
1990 to study the physical determinants on the Antarctic marine ecosystem.
The central tenet of the LTER program is that the annual advance and retreat
of sea ice is a major physical determinant of spatial and temporal changes in
the structure and function of the Antarctic Marine ecosystem, from total
annual primary production to breeding successes in seabirds (Smith et al.
1995).