Seasonal cycles of pelagic production and consumption

An eddy‐permitting coupled physical‐biological model of the North Atlantic: 2. Ecosystem dynamics and comparison with satellite and JGOFS local studies data

“…The maps of surface chlorophyll and primary production, presented in section 3 of the paper, demonstrate that the main patterns and geographical distributions of biological provinces as defined by Longhurst [1995] In order to reach a more quantitative assessment of the coupled model's performance, data from three JGOFS local study sites in different biogeochemical provinces have been used: BATS in the western part of the subtropical gyre, NABE 47øN in the North Atlantic drift region, and EUMELI in the trade wind domain. This led to the identification of two principal model deficiencies.…”

“…We begin with the BATS site in the western subtropical gyre, before analyzing the model results at the NABE 47øN site in the North Atlantic drift province as defined by Longhurst [1995]. Finally, the results of an oligotrophic regime in the trade wind domain in the eastern subtropical gyre will be presented and compared with data taken during the EUMELI cruises.…”

“…These sites are the Bermuda Atlantic Time-series Study (BATS), 32øN, 65øW; the North Atlantic Bloom Experiment (NABE), 47øN, 20øW site; and the EUMELI oligotrophic site (21øN, 31øW). These individual sites may be viewed as representatives of different ecological provinces, ranging from the trade wind region to the northern boundary of the westerlies domain as classified by Longhurst [1995].…”

Role of iron, light, and silicate in controlling algal biomass in subantarctic waters SE of New Zealand

“…Whereas the majority of studies have focused on the waters south of the PF, comparatively little is known about SA waters [Longhurst, 1995;Banse, 1996]. Data are available on phytoplankton biomass (primarily inferred from coastal zone color scanner (CZCS) remote sensing and data archives [Longhurst, 1995;Banse, 1996 [Chang and Gall, 1998] in SA waters. However, little is known about the role of environmental factor(s) in controlling phytoplankton growth and/or determining the size structure of the algal assemblage in SA waters.…”

Major challenges confronting marine biogeochemical modeling

“…Rudimentary, often incomplete community structure models also have been proposed, but as yet, no general model form has gained wide acceptance. Considerable debate has centered on whether it is better to predict species composition or at a minimum functional characteristics, prognostically, parameterize structural responses through more simplified allometric relationships [e.g., Armstrong, 1994], or specify fixed biogeographical regimes in space and time [Longhurst, 1995]. Improved basin-and global-scale compilations of in situ plankton size spectra [Chisholm, 1992], pigment fioristics, and phytoplankton and zooplankton community composition are needed for model testing and satellite algorithm development.…”