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...NPP was calculated for each grid cell and month as the product of photosynthetically active radiation (PAR), fAPAR, and a light use efficiency (LUE) that depended locally on temperature and moisture [=-=Field et al., 1998-=-]. PAR was derived from Bishop and Rossow [1991] and we used GISTEMP temperature anomalies [Hansen et al., 1999] in combination with the CRU 1961–1990 temperature climatology [New et al., 1999] and TR...

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... [2] The accumulation of organic carbon in marine sediments is a key sink of carbon from the ocean-atmosphere system. Only 1% [Sundquist, 1993] of the yearly 50– 60 Pg C of marine primary production [=-=Field et al., 1998-=-] survives sinking through the water column to reach the seabed, making the processes that occur during sinking key to the efficiency of the biological pump. The large regional variability in sinking ...

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...recipitation. 6. Global net primary productivity Present-day global NPP was predicted to be in the range 46.6}49.5 PgC y~1 (Fig. 3) at the low end of the range estimated by others (48.3}67.6 PgC y~1; =-=Field et al., 1998-=-; 44.4}66.3 PgC y~1; Cramer et al., 1999). Low predicted NPP values could be attributed to somewhat low values of short-wave radiation, which were derived from cloud cover in the global observational ...

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...Res., 114, C02004, doi:10.1029/2008JC004979. 1. Introduction [2] Ocean primary production (PP) is a crucial component of the Earth’s biogeochemical cycles of carbon and other major chemical elements [=-=Field et al., 1998-=-]. Net primary production (NPP, g Cm2 d1), i.e., total primary production minus the losses due to respiration of the phytoplankton, provides the upper bound for production at higher trophic levels [...

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...nd fisheries science provide the evidence, tools and information to address these criticisms and confirm MPAs as defensible and feasible instruments for pelagic conservation. Debate over the efficacy of protected areas relative to other conservation measures cannot be resolved without further implementation of MPAs in the pelagic ocean. Introduction The marine pelagic environment is the largest realm on Earth, constituting 99% of the biosphere volume [1]. In addition to supplying >80% of the fish consumed by humans [2], pelagic ecosystems account for nearly half of the photosynthesis on Earth [3], directly or indirectly support almost all marine life and even play a major role in the pace and extent of climate change [4]. Pelagic ecosystems (see Glossary), defined here as the physical, chemical and biological features of the marine water column, now face amultitude of threats including overfishing, pollution, climate change, eutrophication, mining and species introductions (Box 1). These threats can act synergistically [5–7] and can fundamentally alter pelagic ecosystems; important ecosystem components have been supplanted by opportunistic species [5,8], and some pelagic ecosystems ha...

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...vidence that iron plays an important role in seasonal phytoplankton dynamics of the Indian Ocean. Satellite fluorescence may also provide a path for monitoring climate-phytoplankton physiology interactions and improving descriptions of phytoplankton light use efficiencies in ocean productivity models. 1 Introduction Phytoplankton are taxonomically-diverse, single-celled organisms that populate the upper sunlit layer of nearly all water bodies on Earth, and they are photosynthetic. Net annual photosynthesis by ocean phytoplankton alone is of similar magnitude as that by all terrestrial plants (Field et al., 1998; Behrenfeld et al. 2001) and it plays a vital role in biospheric carbon cycling. Ocean productivity is strongly impacted by climate variations (Gregg et al., 2005; Behrenfeld et al., 2006a), but quantifying this impact and predicting future change requires an understanding of environmental factors regulating phytoplankton light use efficiencies and growth (Behrenfeld et al., 2008). However, globally characterizing physiological variability has proven far more Published by Copernicus Publications on behalf of the European Geosciences Union. 780 M. J. Behrenfeld et al.: Fluorescence reveals Glo...