Denis Wiesenburg - Academia.edu (original) (raw)

Papers by Denis Wiesenburg

Abstract : Between 19 and 22 September 1983, over 50 scientists met at the Naval Ocean Research a... more Abstract : Between 19 and 22 September 1983, over 50 scientists met at the Naval Ocean Research and Development Activity (NORDA) to discuss issues related to the study of biological and chemical processes at oceanic fronts. In lieu of the publication of NORDA Report 78, this document has been printed to distribute the abstracts of the meeting. It was evident from the discussion of this workshop that rapid progress could be made in understanding chemical variability and processes at fronts, if a coordinated plan of research is pursued. The scope of the work to be done is multidisciplinary and extensive; this is a problem that would benefit greatly from a long-range, multi-investigator, coordinated study. The major components of such an investigation would include: 1) satellite and aircraft remote sensing, 2) physical characterization of the frontal system and its exchange processes, 3) measurements of chemical gradients and rates for substances participating in biological, photochemical, and solid phase processes, and 4) determination of the abundance and rates of biological activity associated with a front. It is likely that there is a wide range of frontal systems in the ocean that need to be distinguished. A coordinated investigation would provide the greatest advancement of knowledge for a given investment of resources. Keywords: Marine biology, Chemical oceanography, Upwelling, Gases, Geochemistry, Heat transfer, Salinity, Phytoplankton, Contaminated shelf.

Abstract : Several years ago the Naval Ocean Research and Development Activity initiated a projec... more Abstract : Several years ago the Naval Ocean Research and Development Activity initiated a project to examine the interrelationships between dissolved trace gases and suspended particulate material in the upper water column of the world oceans. The goal of the project was to observe and understand the variations in biological parameters, gas distributions and suspended particulate layers to provide an assessment of in situ gas production mechanisms associated with particulate material. This report is a summary of data collected in the western North Atlantic Ocean in the summer of 1982 aboard USNS LYNCH, Cruise 710-82. Vertical profiles through most of the water column were obtained for the following parameters: conductivity, temperature, salinity, nephelometry, transmissometry, total suspended matter, dissolved and particulate organic carbon, adenosine triphosphate (ATP), chlorophyll and phaeopigments, nutrients (nitrate), nitrite, ammonium, phosphate, silicate), dissolved oxygen and dissolved reduced gases (methane and nitrous oxide). Tables of the measured and certain derived parameters are given, along with descriptions of the collection and analytical procedures.

Proceedings of the 16th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS/GNSS 2003), Sep 12, 2003

Proceedings of SPIE, Aug 12, 1988

ABSTRACT Continuous measurements of spectral upwelling irradiance were made across strong frontal... more ABSTRACT Continuous measurements of spectral upwelling irradiance were made across strong frontal regions in the Western Mediterranean Sea using a surface towed instrument system. Frontal zones in the region can be observed from changes in temperature, salinity, and transmis-sivity. The remote sensing reflectance and the ratio of 441 to 550 nanometer upwelling radiance are shown to discriminate between different water masses across these frontal zones. Surface optical properties are related to the physical processes in the upper water column and are representative of the vertical physical structure. In situ measurements of the spectral upwelling irradiance can improve our interpretation of data from ocean color satellite systems.

Abstract : This report is a summary and analysis of data collected during the spring of 1983 in E... more Abstract : This report is a summary and analysis of data collected during the spring of 1983 in Exuma Sound, Bahamas, and in the Gulf Stream at the Straits of Florida. Vertical profiles in the upper water column were obtained to characterize biological and chemical parameters, which might covary with propeller cavitation susceptibility. Examination of this data set reveals that Exuma Sound is a relatively homogeneous body of water with respect to the biological and chemical measurements that were made. It is an aquatic 'desert', and any measurements made there of a parameter that may be influenced by biological or chemical activity cannot necessarily be extrapolated to other marine environments. This is especially true in regards to the more fertile regions, which exist in higher latitudes and coastal zones.

This document describes the scientific program and field plan for operation GUIDING LIGHT, the pi... more This document describes the scientific program and field plan for operation GUIDING LIGHT, the pilot field experiment for the NORDA project Chemical Dynamics in Ocean Frontal Areas. The study area for GUIDING LIGHT is the western North Atlantic Ocean off the eastern coast of the United States. The operation will be conducted from 18 April to 10 May 1985. The fronts to be examined during this pilot experiment are the Gulf Stream front and shelf-slope front off New England. GUIDING LIGHT will employ rapid sampling and analytical capabilities to measure chemical-biological-physical variations in surface waters at these frontal boundaries. Both shipboard and remotely sensed observations will be made. The field operation will be conducted from one ship (USNS BARTLETT), three aircraft, and the space shuttle (STS 51-B). Participants in GUIDING LIGHT include investigators from the Naval Ocean Research and Development Activity,

Continental Shelf Research, Feb 1, 1997

... Guffy and Mark Spears for measurements of salinity and nutrients, Robert Albers for keeping t... more ... Guffy and Mark Spears for measurements of salinity and nutrients, Robert Albers for keeping the CTD alive during cruise 93E, Ann Jochens for assisting in CTD operations and Capt. Pat Sherrard and the crew of the research vessel JW Powell for their support. Linwood L. Lee III ...

Environmental Science & Technology, May 1, 1982

Page 1. Environ. Sei. Technol. 1982, 16, 278-282 Systems, Parts I and 11, EPA Reports 60017-77-11... more Page 1. Environ. Sei. Technol. 1982, 16, 278-282 Systems, Parts I and 11, EPA Reports 60017-77-113 and 600/7-78-074. Chemosphere 1978, 7, 734. Arthur D. Little Inc. and Rosenblatt, D. H., Research and Development Methods ...

Environmental Science & Technology, Aug 1, 1981

Page 1. Acknowledgment This paper is the result of a collaborative study. The authors express the... more Page 1. Acknowledgment This paper is the result of a collaborative study. The authors express their gratitude to the technical staff of the Bedford Institute of Oceanography and to the officers and men of the research vessel CSS Hudson. ...

The Texas A&M University deep towed pumping system is an apparatus designed to tow a fish-like bo... more The Texas A&M University deep towed pumping system is an apparatus designed to tow a fish-like body containing a pump and a CSTD (conductivity , salinity, temperature and depth) probe at depths down to 150 meters , w h i l e the towing vessel is underway at full speed. This survey unit has the capability of pumping eight liters per minute of sea water to analytical equipment on deck while simultaneously measuring the salinity , tempera ture and depth at which the towed body is deployed. An on-deck data acquisition system and controlling computer automatically record the CSTD data and provide real-time results that can be used in determining the cruise track or the specific area to be surveyed. This system was deployed on R/V GYRE Cruise 77-G-14 (3-7 December 1977) to test recent modifications , as well as to determine the reliabilit y and use fu l ness of a towed pumpi ng sys tem for oceano gra phi c research i n sur face waters. The mechanical system operated reliably and the towed CSTD data was recorded automatically. Sample water pumped from depths down to 108 meters in the Gulf of Mexico was analyzed for salinit y , dissolved oxygen , phosphate , silicate and nitrate. The towed pumping system results compared favorably

Applied and Environmental Microbiology, 1979

The Orca Basin is a hypersaline depression in the northern Gulf of Mexico with anoxic conditions ... more The Orca Basin is a hypersaline depression in the northern Gulf of Mexico with anoxic conditions observed in the lower 200 m of the water column. Measurements of adenosine 5′-triphosphate, heterotrophic potential, and uridine uptake made above and across the interface into the anoxic zone revealed the presence of an active microbial population approximately 100 m above the interface. Biomass and activity decreased at and just below the interface but increased near the bottom, consistent with similar observations made in the Cariaco Trench. The maximum adenosine 5′-triphosphate concentration above the interface of 5.9 ng/liter (2,173 m) is about eight times greater than the value found in oxygenated waters of corresponding depth in the absence of an anoxic zone. The maximum adenosine 5′-triphosphate concentration in the anoxic zone is approximately 15 times greater than that found in oxygenated water of similar depth, suggesting anoxia will support the development of a larger bacteri...

Ocean Science Directorate NSTL, Mississippi 39529-5004 8a. NAME OF FUNDING/SPONSORING ORGANIZATIO... more Ocean Science Directorate NSTL, Mississippi 39529-5004 8a. NAME OF FUNDING/SPONSORING ORGANIZATION Naval Ocean Research and Development Activity 8b. OFFICE SYMBOL (it applicable) 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER 8c. ADDRESS (City, State, and ZIP Code) Ocean Science Directorate NSTL, Mississippi 39529-5004 10. SOURCE OF FUNDING NOS.

Abstract : During June 1987, researchers from the Naval Ocean Research and Development Activity (... more Abstract : During June 1987, researchers from the Naval Ocean Research and Development Activity (NORDA) participated in a cruise in the Norwegian Sea aboard the WFS PLANET. They collected high precision conductivity temperature depth (CTD) measurements at fifty-one (51) stations using a Neil Brown Mark IIIB CTD with an attached in situ fluorometer. The CTD stations were situated along one transect between the Shetland and Faeroe Islands and along three other transects which crossed frontal boundaries in the Norwegian Sea proper. Many of the stations were coincident with orbits of the Navy's GEOSAT satellite. From these data, the dynamic height at each station will be calculated in order to correlate and verify GEOSAT altimetric measurements with oceanographic data along the altimeter ground tracks. This report describes the preliminary results produced by NORDA from the WFS PLANET cruise, NORDMEER 87. The purpose of the cruise is described and a detailed listing of station locations and data collected are provided. All procedures used for instrument calibration, data collection, verification and processing are given. Vertical profiles of potential temperature, salinity (PSS78), sigma theta and relative chlorophyll fluorescence are presented for each station. A plot of potential temperature versus salinity for each station is also given. Contour plots of temperature and salinity for the four transects are used to describe the different water masses in the region.

Ocean Optics IX, 1988

Journal of Marine Systems, 2000

Ž. The northwest NW Gulf of Mexico is marked by strong seasonal patterns in regional and mesoscal... more Ž. The northwest NW Gulf of Mexico is marked by strong seasonal patterns in regional and mesoscale circulation and variable effects of riverinerestuarine discharge, which influence distributions of nutrients, phytoplankton biomass and primary production. During a series of five cruises in the NW Gulf of Mexico in 1993 and 1994, an extensive data set was Ž. Ž. collected including nutrients, phytoplankton biomass chlorophyll a , and photosynthesis-irradiance P-E parameters. Primary production was estimated using P-E parameters in conjunction with profiles of biomass and irradiance. Relatively high biomass and primary production were observed in inner shelf waters during spring conditions of high river discharge. This was attributed to the retention of biomass and nutrients on the shelf by the combination of high river outflow and a westward flow along the inner shelf with consequent onshore Ekman component. During summer, when surface currents shifted towards the north and east, values of nutrients, biomass and primary production were relatively high east of Galveston Bay and decreased outward from the coast. This pattern was apparently a consequence of nutrient inputs from riverine, upwelling and benthic sources. Nutrients, biomass and productivity in the western portion of the study area in summer were generally lower as a result of the upcoast flow of oligotrophic offshore water. Inter-annual variability was observed between November 1993 and 1994 with higher biomass and productivity occurring in November 1993. This was partially attributed to higher river discharge prior to November 1993, retention of biomass and nutrients by the downcoast flow along the inner shelf, and possibly, injection of nutrients onto the shelf at the shelf break. Our findings demonstrate that the interaction of circulation and availability of light and nutrients are largely responsible for variations in primary production. Nitrogen appeared to be the primary limiting nutrient, however, a potential for phosphate limitation was also observed particularly during periods of higher river discharge. Light availability was a critical variable during the fall and winter months, when higher primary production was restricted to shallow waters where vertical mixing was constrained by bottom topography. In deep waters, counteractive changes in nutrient and light availability apparently resulted in minor Ž. temporal variation between seasons. The annual carbon production in the Louisiana-Texas LATEX continental shelf region was estimated to be 159 g C m y2 year y1 , which is within the range of prior estimates for this region. Given that the area of the study region was approximately 140,000 km 2 , this would be equivalent to an areal carbon production of about 22.2 million metric tons.