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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 103, NO. C8,
PAGES 15,587–15,600,
1998
Primary production in Southern Ocean waters
Kevin R. Arrigo
Oceans and Ice Branch, NASA Goddard Space Flight Center, Greenbelt, Maryland
Denise Worthen
Science Systems and Applications, Inc., Lanham, Maryland
Anthony Schnell
Department of Biology and Microbiology, University of Wisconsin Oshkosh, Oshkosh
Michael P. Lizotte
Department of Biology and Microbiology, University of Wisconsin Oshkosh, Oshkosh
Abstract
The Southern Ocean forms a link between major ocean basins, is the site of deep and intermediate water ventilation, and is
one of the few areas where macronutrients are underutilized by phytoplankton. Paradoxically, prior estimates of annual primary
production are insufficient to support the Antarctic food web. Here we present results from a primary production algorithm
based upon monthly climatological phytoplankton pigment concentrations from the coastal zone color scanner (CZCS). Phytoplankton
production was forced using monthly temperature profiles and a radiative transfer model that computed changes in photosynthetically
usable radiation at each CZCS pixel location. Average daily productivity (g C m−2 d−1) and total monthly production (Tg C month−1) were calculated for each of five geographic sectors (defined by longitude) and three ecological provinces (defined by sea
ice coverage and bathymetry as the pelagic province, the marginal ice zone, and the shelf). Annual primary production in the
Southern Ocean (south of 50°S) was calculated to be 4414 Tg C yr−1, 4–5 times higher than previous estimates made from in situ data. Primary production was greatest in the month of December
(816 Tg C month−1) and in the pelagic province (contributing 88.6% of the annual primary production). Because of their small size the marginal
ice zone (MIZ) and the shelf contributed only 9.5% and 1.8%, respectively, despite exhibiting higher daily production rates.
The Ross Sea was the most productive region, accounting for 28% of annual production. The fourfold increase in the estimate
of primary production for the Southern Ocean likely makes the notion of an “Antarctic paradox” (primary production insufficient
to support the populations of Southern Ocean grazers, including krill, copepods, microzooplankton, etc.) obsolete.
Received 23
October
1997;
accepted 19
March
1998.
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Citation: Arrigo, K. R., D. Worthen, A. Schnell, and M. P. Lizotte
(1998),
Primary production in Southern Ocean waters,
J. Geophys. Res.,
103(C8),
15,587–15,600.
Copyright 1998 by the American Geophysical Union.
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