Browsing by Author "Cullen, John J."
Now showing items 1-14 of 14
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Assessment of the relationships between dominant cell size in natural phytoplankton communities and the spectral shape of the absorption coefficient
Ciotti, Aurea M.; Lewis, Marlon R.; Cullen, John J. (2002-03)Size-fractionated chlorophyll concentration and phytoplankton absorption spectra were compared for a wide variety of natural communities. We found that, in general, when phytoplankton abundance increases, larger size-classes ... -
Changes in buoyancy and chemical composition during growth of a coastal marine diatom: Ecological and biogeochemical consequences
Richardson, Tammi L.; Cullen, John J. (1995)Growth and sinking of the coastal marine diatom Thalassiosira weissflogii was studied during experiments in a 2.1 m tall water column. Under nutrient-replete conditions, T. weissflogii grew rapidly in the upper layer of ... -
Inferred influence of nutrient availability on the relationship between Sun-induced chlorophyll fluorescence and incident irradiance in the Bering Sea
Schallenberg, Christina; Lewis, Marlon R.; Dan E Kelley,; Cullen, John J. (American Geophysical Union, 2000 Florida Ave., N.W. Washington DC 20009 USA, [mailto:service@agu.org], [URL:http://www.agu.org], 2008-08)This study examines variability in the relationship between Sun-induced chlorophyll fluorescence and incident solar irradiance as a potential diagnostic of the nutritional status of phytoplankton. The study site is the ... -
Methyl iodide in the NW Atlantic: Spatial and seasonal variation
Wang, Lu; Moore, Robert M.; Cullen, John J. (2009-07)While the global ocean is an important source of atmospheric methyl iodide (CH(3)I), the major producers of CH(3)I within the ocean remain unclear. During a seasonal study in the NW Atlantic, the relationship between CH(3)I ... -
Methyl iodide in the NW Atlantic; spatial and seasonal variation
Wang, Lu; Moore, Robert M.; Cullen, John J. (American Geophysical Union, Washington, DC, 2009)While the global ocean is an important source of atmospheric methyl iodide (CH (sub 3) I), the major producers of CH (sub 3) I within the ocean remain unclear. During a seasonal study in the NW Atlantic, the relationship ... -
Modeling the effects of ultraviolet radiation on embryos of Calanus finmarchicus and Atlantic cod (Gadus morhua) in a mixing environment
Kuhn, Penny S.; Browman, Howard I.; Davis, Richard F.; Cullen, John J.; McArthur, Bruce L. (2000-12)It is well established that ultraviolet radiation (UVR, 280-400 nm) harms aquatic organisms. Reductions in productivity have been reported for phytoplankton, ichthyoplankton, and zooplankton in incubations exposed to UVR. ... -
Ocean Fertilization Science, Policy, and Commerce
Strong, Aaron L.; Cullen, John J.; Chisholm, Sallie W. (2009-09)Over the past 20 years there has been growing interest in the concept of fertilizing the ocean with iron to abate global warming. This interest was catalyzed by basic scientific experiments showing that iron limits primary ... -
Optical detection and assessment of algal blooms
Cullen, John J.; Ciotti, Aurea M.; Davis, Richard F.; Lewis, Marlon R. (1997-07)Concerns about harmful algal blooms (HABs) have grown in recent years. There is a pressing need for robust, quantitative, and cost-effective methods to detect and characterize algal blooms. Critical applications of these ... -
Patterns and Prediction in Microbial Oceanography
Cullen, John J.; Doolittle, W. Ford; Levin, Simon A.; Li, William K. W. (2007-06)No abstract available. -
Predicting and verifying the intended and unintended consequences of large-scale ocean iron fertilization
Cullen, John J.; Boyd, Philip W. (2008)Ocean iron fertilization (OIF) is being considered as a strategy for mitigating rising atmospheric CO2 concentrations. One model for implementation is the sale of carbon offsets. Modeling studies predict that OIF has the ... -
Retrieval of phytoplankton biomass from simultaneous inversion of reflectance, the diffuse attenuation coefficient, and Sun-induced fluorescence in coastal waters
Huot, Yannick; Brown, Catherine A.; Cullen, John J. (2007-06)[1] A model has been developed to retrieve phytoplankton absorption, a proxy for phytoplankton biomass, from observations of reflectance ( R) and the diffuse attenuation coefficient (K-d) collected by moored radiometers ... -
Spectrally weighted transparency in models of water-column photosynthesis and photoinhibition by ultraviolet radiation
Lehmann, Moritz K.; Davis, Richard F.; Huot, Yannick; Cullen, John J. (2004)We present a simple method for describing the influence of variable attenuation of spectral irradiance, Kd(lambda), on water-column photosynthesis and its inhibition by ultraviolet radiation (UV). The approach is based on ... -
Status of the iron hypothesis after the open-ocean enrichment experiment
Cullen, John J. (1995)No abstract available. -
Vertical migration, nutrition and toxicity in the dinoflagellate Alexandrium tamarense
Macintyre, J. Geoff; Cullen, John J.; Cembella, Allan D. (1997)The effect of nitrate-N availability on paralytic shellfish toxin production by the dinoflagellate Alexandrium tamarense was studied in a vertically stratified laboratory water column (tank) where swimming behavior could ...