OS13A-2016
Phytoplankton Bloom Phenology near Palmer Station Antarctica
Monday, 14 December 2015
Poster Hall (Moscone South)
Laura Crews, Stanford University, Stanford, CA, United States, Scott C Doney, Woods Hole Oceanographic Inst, Woods Hole, MA, United States, Maria Kavanaugh, Woods Hole Oceanographic Institution, Woods Hole, United States, Hugh W Ducklow, Lamont -Doherty Earth Observatory, Division of Biology and Paleo Environment, Palisades, NY, United States, Oscar Schofield, Rutgers University, New Brunswick, NJ, United States and David M Glover, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
Abstract:
West Antarctic Peninsula (WAP) phytoplankton bloom phenology is coupled to growing season water column stratification precipitated by seasonal warming and the melting of winter sea-ice. Previous studies document declining bloom magnitude over decadal timescales in conjunction with decreasing sea-ice extent and duration in the Northern WAP, but less work has been to done explain the observed inter-annual variability in this region. Here we use a high-resolution in situ time series collected by the Palmer Station Antarctica Long Term Ecological Research program and satellite ocean color imagery to investigate the underlying mechanisms controlling phytoplankton bloom timing and magnitude near Palmer Station. We pair chlorophyll and CTD measurements collected twice per week during the austral summer, 1992—2003, with satellite ocean color and ice fractional cover data to examine bloom development and within-season trends in mixed layer depth. Initial results suggest a possible shift over time with spring/summer blooms occurring earlier in the growing season reflecting earlier sea-ice free conditions. Net phytoplankton accumulation rates are also computed and compared against growth estimates. Our results can be used to develop and validate models of coastal Antarctic primary production that better represent inter-annual primary production variability.
