A5011237257- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Oceanographic and Atmospheric Processes
- Microbial Community Ecology and Physiology
- Atmospheric and Environmental Gas Dynamics
- Spectroscopy Techniques in Biomedical and Chemical Research
- Calibration and Measurement Techniques
- Infrared Target Detection Methodologies
- Polar Research and Ecology
- Marine and fisheries research
- Photonic and Optical Devices
- Spectroscopy and Laser Applications
- Atmospheric chemistry and aerosols
- Advanced Semiconductor Detectors and Materials
- Coral and Marine Ecosystems Studies
- Atmospheric aerosols and clouds
- Laser-induced spectroscopy and plasma
- Arctic and Antarctic ice dynamics
- Marine and Offshore Engineering Studies
- Advanced Chemical Sensor Technologies
- Environmental Monitoring and Data Management
- CCD and CMOS Imaging Sensors
- Spectroscopy and Chemometric Analyses
- Optical Systems and Laser Technology
- bioluminescence and chemiluminescence research
Millersville University
2011-2020
Optra (United States)
2006-2013
Lamont-Doherty Earth Observatory
2003-2009
Columbia University
2003-2009
Bigelow Laboratory for Ocean Sciences
2000
University of Rhode Island
1989
Biogenic sources contribute to cloud condensation nuclei (CCN) in the clean marine atmosphere, but few measurements exist constrain climate model simulations of their importance. The chemical composition individual atmospheric aerosol particles showed two types sulfate-containing air masses addition mass-based Estimated Salt particles. Both sulfate lack combustion tracers and correlate, for some conditions, or seawater dimethyl sulfide (DMS) concentrations, which means source was largely...
Spectral backscattering coefficients were determined for 29 species of cultured marine plankton representing 12 classes using a fixed-angle meter. Using multi-angle scattering meter, the volume function was measured and proportionality constant (χ) between β(141°) bb as 0.82 (±0.01 SE), less than χ value 1.08 reported natural waters. Backscattering efficiencies (at 440 nm) cultures varied 0.0023 0.081 showed little spectral variation. Plankton at 510 nm lowest variability when normalized to...
We use continuous and discrete measurements of the dissolved O 2 /Ar ratio in mixed layer to investigate dynamics biological productivity during Southern Ocean Gas Exchange Experiment March April 2008. Injections SF 6 defined two water masses (patches) that were followed for up weeks. In first patch, was supersaturated, indicating net production organic carbon. second rapidly decreasing could only be reasonably explained if experiencing a period heterotrophy. The observations rule out...
[1] Optical properties and primary production were measured during the Southern Ocean (SO) Gas Exchange Experiment (GasEx) (March–April 2008). To assess evaluate these derived from remote sensing, absorption coefficients sensing reflectance (Rrs) with quasi-analytical algorithm compared those in situ measurements both an ac-9 optical instrument deployed on a profiling package discrete water samples analyzed using filter pad spectrophotometry. Total Rrs retrievals found, average, to be ∼12%...
Light scattering properties of biogenic CaCO 3 particles [particulate inorganic carbon (PIC)] were determined on cultured calcifying algae and field‐derived particles. The separated from particulate organic (POC) with a flow cytometer, volume‐scattering functions measured laser light‐scattering photometer, particle composition was using atomic absorption spectrometry. Small calcite coccoliths best sorted by gating the ratio horizontally polarized forward light vertically scattering; plated...
Abstract The database on ocean primary productivity comprises over two decades (1985–2008) of data that the authors have participated in collecting, using assimilation inorganic 14 C through photosynthesis, incubations carried out situ. dataset is perhaps unique it uses, overwhelmingly, consistent methodology while covering a wide geographic range. Ancillary are included. Using database, hoped investigators can test for relationships among environmental drivers productivity, meaning method...
Viruses represent one of the most abundant, ocean‐borne particle types and have significant potential for affecting optical backscattering. Experiments addressing light‐scattering properties viruses heretofore not been conducted. Here we report results laboratory experiments in which volume‐scattering functions several bacterial (bacteriophages) were measured at varying concentrations with a laser photometer using He‐Ne and/or Argon ion (632.8 514.0 nm, respectively). Four size examined,...
We investigated mixed‐layer bioluminescence from early April to late September (in 1989, May 1991, July 1983 and 1990, August 1988 1989) at stations near the Marine‐Light ‐ Mixed Layers (MLML) bio‐optical moorings site. Volume‐specific potential (BPOT, photons per unit volume) epipelagic organisms was estimated directly with a pump‐through photometer (BP) in 1983, 1988, 1991. For all cruises, BPOT also by summing for volume of seawater, measurements each species′ total stimulable multiplied...
Flow field‐flow fractionation (flow FFF) with power field‐strength programming was used to size fractionate submicron particles (colloids) in coastal seawater. All analyses filtered seawater as carrier solution preserve the native chemical environment of colloids. Our fractograms show colloid distributions major peaks centered at 50 60 nm for samples that were fractionated immediately following preconcentration step. Preconcentrated had aged 2 5 d revealed presence an additional larger sized...
Temporal and spatial acoustic backscatter estimates of Zooplankton biomass were made using an unmodified hull‐mounted 153‐kHz Doppler current profiler (ADCP) during the May 1991 Marine Light‐Mixed Layers (MLML) cruises to North Atlantic. Relative from ADCP was converted individual plankton taxa abundances weights samples collected cruises. There a small but consistent diel pattern in 20 250‐m depth‐integrated backscatter, with highest values darkness. Removal signal harmonic analysis...
A fine‐scale survey of physical, chemical, and optical properties was done across the shelfbreak front in Middle Atlantic Bight region south Martha's Vineyard, Cape Cod (70.5°W) during late summer 2002. The displayed physical biological structure typical for this season: a density‐compensating with strong horizontal T S gradients, chlorophyll maximum layer that deepened seaward direction front, became detached beneath jet, reappeared on deeper greater density surface side then shoaled again...
Bio-optical characteristics of phytoplankton and carbon assimilation were measured in the NW Atlantic Ocean near continental shelf break South New England (40°N/70°W) August 2002. Discrete samples included: chlorophyll a (Chl a), absorption (aph), photosynthetic versus irradiance (P E) response using fixation, maximum quantum yield for charge separation at Photosystem II (PSII) (Fv/Fm) its recovery kinetics functional cross-section (σPSII). In this study, we present robust empirical...
A study on the growth in size and weight of Winter Flounder, Pseudopleuronectes americanus (Walbaum), was conducted from samples collected during summers 1979 1980, bay Saint-Fabien-sur-Mer (Québec) south shore Lower St. Lawrence Estuary. Age determined by otolith readings length–weight relationships were calculated. Linear equations not statistically different for males females. On other hand, found to be higher females than equal sizes. This relationship also varies with sampling period, a...
Biological uptake rates of inorganic carbon and nitrate were measured during two sequential tracer release gas exchange experiments, together known as the Southern Ocean Gas Exchange Experiment (SO GasEx) in southwest Atlantic sector Antarctic Zone (51°N, 38°W). Primary productivity estimated from 14 C incubations ranged 26.7 to 47.2 mmol m −2 d −1 first experiment (Patch 1) 13.7 39.4 second 2). Nitrate‐based 15 NO 3 5.8 13.1 Patch 1 1.9 7.1 2. The average ratio nitrate‐based primary...
OPTRA is developing a two-band midwave infrared (MWIR) scene simulator based on digital micromirror device (DMD) technology; this intended for training various IR threat detection systems that exploit the relative intensities of two separate MWIR spectral bands. Our approach employs DMDs, one each band, and an efficient optical design which overlays scenes reflected by through common telecentric projector lens. Other key components include miniature thermal sources, bandpass filters,...