1BIO-OPTICAL MODELING OF PRIMARY PRODUCTION FROM SEAWIFS OCEAN COLOR DATA FOR THE WESTERN ANTARCTIC PENINSULA REGION

• Main Authors: Raymond C. Smith, Karen S. Baker, Heidi M. Dierssen, Sharon E. Stammerjohn, Maria Vernet
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Southern Ocean; Antarctic Peninsula; Antarc*; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.634.8224; http://pal.lternet.edu/docs/bibliography/Public/208lterc.pdf

Waters of the Southern Ocean are bio-optically distinct. These waters are characterized by a pronounced seasonal variability in incoming solar radiation, low temperatures, generally high inorganic nutrients, as well as the presence, formation, and melting of sea ice. Phytoplankton populations in waters of the Southern Ocean have a maximum chlorophyll-specific carbon fixation rate within the water column which, consistent with low water temperatures, is low compared to those in more temperate waters. The corresponding optical properties of these waters generally show both low chlorophyll-specific absorption and low back-scattering which leads to significantly distinct remote sensing reflectance. As a consequence, algorithms for the estimation of satellite derived chlorophyll and subsequent modeling of primary production are unique for these waters. In this work, we evaluate the spatial and temporal variability of primary production (determined in-situ aboard ship as well as estimated from SeaWiFS ocean color satellite data). We also present the spatial and temporal variability of sea ice extent (estimated from passive microwave satellite data). Even though persistent spatial patterns have been observed over the many years of study (e.g., an onshore to offshore gradient in biomass and a growing season characterized by episodic phytoplankton blooms), this marine ecosystem displays extreme interannual variability in both phytoplankton biomass and primary production. This high interannual variability at the base of the food chain influences organisms at all trophic levels.