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Full-Text Articles in Physical Sciences and Mathematics

Scientific Basis For Safely Shutting In The Macondo Well After The April 20, 2010 Deepwater Horizon Blowout, Stephen H. Hickman, Paul A. Hsieh, Walter D. Mooney, Catherine B. Enomoto, Philip H. Nelson, Larry A. Mayer, Thomas C. Weber, Kathryn Moran, P. B. Flemings, Marcia Mcnutt Dec 2012

Scientific Basis For Safely Shutting In The Macondo Well After The April 20, 2010 Deepwater Horizon Blowout, Stephen H. Hickman, Paul A. Hsieh, Walter D. Mooney, Catherine B. Enomoto, Philip H. Nelson, Larry A. Mayer, Thomas C. Weber, Kathryn Moran, P. B. Flemings, Marcia Mcnutt

Center for Coastal and Ocean Mapping

As part of the government response to the Deepwater Horizon blowout, a Well Integrity Team evaluated the geologic hazards of shutting in the Macondo Well at the seafloor and determined the conditions under which it could safely be undertaken. Of particular concern was the possibility that, under the anticipated high shut-in pressures, oil could leak out of the well casing below the seafloor. Such a leak could lead to new geologic pathways for hydrocarbon release to the Gulf of Mexico. Evaluating this hazard required analyses of 2D and 3D seismic surveys, seafloor bathymetry, sediment properties, geophysical well logs, and drilling …


Overview Of The 2007 And 2008 Campaigns Conducted As Part Of The Greenland Summit Halogen-HoX Experiment (Gshox), J L. Thomas, Jack E. Dibb, J Stutz, R Von Glasow, Steve Brooks, L Gregory Huey, Barry Lefer Nov 2012

Overview Of The 2007 And 2008 Campaigns Conducted As Part Of The Greenland Summit Halogen-HoX Experiment (Gshox), J L. Thomas, Jack E. Dibb, J Stutz, R Von Glasow, Steve Brooks, L Gregory Huey, Barry Lefer

Earth Sciences

From 10 May through 17 June 2007 and 6 June through 9 July 2008 intensive sampling campaigns at Summit, Greenland confirmed that active bromine chemistry is occurring in and above the snow pack at the highest part of the Greenland ice sheet (72°36´ N, 38°25´ W and 3.2 km above sea level). Direct measurements found BrO and soluble gas phase Br mixing ratios in the low pptv range on many days (maxima < 10 pptv). Conversion of up to 200 pg m−3 of gaseous elemental mercury (GEM) to reactive gaseous mercury (RGM) and enhanced OH relative to HO2 plus RO2 confirm that active bromine chemistry is …


Calibration Of Multibeam Echo Sounders: A Comparison Between Two Methodologies, Carlo Lanzoni, Thomas C. Weber Nov 2012

Calibration Of Multibeam Echo Sounders: A Comparison Between Two Methodologies, Carlo Lanzoni, Thomas C. Weber

Center for Coastal and Ocean Mapping

Multibeam echo sounders (MBES) are widely used in applications like seafloor imaging, fisheries, and habitat mapping. Calibration of acoustic backscatter is an important aspect of understanding and validating the performance of a MBES. Combined transmit/receive beampattern calibrations were performed on a 200 kHz Reson Seabat 7125 MBES in the acoustic tank of the University of New Hampshire utilizing two different methodologies. The first methodology employs fixed standard target spheres and a high accuracy/high resolution rotation mechanism. This method, similar to that proposed by Foote et al ["Protocols forcalibrating multibeam sonar", J. Acoust. Soc. Am. 117(4), 2005], is designed for a …


Spectral Absorption Of Biomass Burning Aerosol Determined From Retrieved Single Scattering Albedo During Arctas, C A. Corr, S R. Hall, B E. Anderson, Kirk Ullman, A J. Beyersdorf, Kenn L. Thornhill, Michael J. Cubison, Jose L. Jimenez, Armin Wisthaler, Jack E. Dibb Nov 2012

Spectral Absorption Of Biomass Burning Aerosol Determined From Retrieved Single Scattering Albedo During Arctas, C A. Corr, S R. Hall, B E. Anderson, Kirk Ullman, A J. Beyersdorf, Kenn L. Thornhill, Michael J. Cubison, Jose L. Jimenez, Armin Wisthaler, Jack E. Dibb

Earth Sciences

Actinic flux, as well as aerosol chemical and optical properties, were measured aboard the NASA DC-8 aircraft during the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) mission in Spring and Summer 2008. These measurements were used in a radiative transfer code to retrieve spectral (350-550 nm) aerosol single scattering albedo (SSA) for biomass burning plumes encountered on 17 April and 29 June. Retrieved SSA values were subsequently used to calculate the absorption Angstrom exponent (AAE) over the 350-500 nm range. Both plumes exhibited enhanced spectral absorption with AAE values that exceeded 1 (6.78 ± …


Potentially Polluting Marine Sites Geodb: An S-100 Geospatial Database As An Effective Contribution To The Protection Of The Marine Environment, Giuseppe Masetti, Brian R. Calder, Lee Alexander Nov 2012

Potentially Polluting Marine Sites Geodb: An S-100 Geospatial Database As An Effective Contribution To The Protection Of The Marine Environment, Giuseppe Masetti, Brian R. Calder, Lee Alexander

Center for Coastal and Ocean Mapping

Potentially Polluting Marine Sites (PPMS) are objects on, or areas of, the seabed that may release pollution in the future. A rationale for, and design of, a geospatial database to inventory and manipu-late PPMS is presented. Built as an S-100 Product Specification, it is specified through human-readable UML diagrams and implemented through machine-readable GML files, and includes auxiliary information such as pollution-control resources and potentially vulnerable sites in order to support analyses of the core data. The design and some aspects of implementation are presented, along with metadata requirements and structure, and a perspective on potential uses of the database.


Characteristics Of Tropospheric Ozone Depletion Events In The Arctic Spring: Analysis Of The Arctas, Arcpac, And Arcions Measurements And Satellite Bro Observations, T P. Kurosu, Yuhang Wang, T P. Kurosu, K Chance, A Rozanov, A Richter, S J. Oltmans, A M. Thompson, Jonathan Hair, Marta Fenn, Andrew Weinheimer, Thomas B. Ryerson, S Solberg, L Gregory Huey, J Liao, Jack E. Dibb, J A. Neuman, J Nowak, B Pierce, M Natarajan, J Al-Saadi Oct 2012

Characteristics Of Tropospheric Ozone Depletion Events In The Arctic Spring: Analysis Of The Arctas, Arcpac, And Arcions Measurements And Satellite Bro Observations, T P. Kurosu, Yuhang Wang, T P. Kurosu, K Chance, A Rozanov, A Richter, S J. Oltmans, A M. Thompson, Jonathan Hair, Marta Fenn, Andrew Weinheimer, Thomas B. Ryerson, S Solberg, L Gregory Huey, J Liao, Jack E. Dibb, J A. Neuman, J Nowak, B Pierce, M Natarajan, J Al-Saadi

Earth Sciences

Arctic ozone depletion events (ODEs) are caused by halogen catalyzed ozone loss. In situ chemistry, advection of ozone-poor air mass, and vertical mixing in the lower troposphere are important factors affecting ODEs. To better characterize the ODEs, we analyze the combined set of surface, ozonesonde, and aircraft in situ measurements of ozone and bromine compounds during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC), and the Arctic Intensive Ozonesonde Network Study (ARCIONS) experiments (April 2008). Tropospheric BrO columns retrieved from satellite measurements and back …


Using A Cruise Report To Generate Xml Metadata, Briana M. Sullivan Oct 2012

Using A Cruise Report To Generate Xml Metadata, Briana M. Sullivan

Center for Coastal and Ocean Mapping

Since 2005 metadata generation at the Center for Coastal and Ocean Mapping/Joint Hydrographic Center has slowly evolved from a painful and tedious process of copying and pasting, to generate hundreds of files, to using an automated system that generates 90% of the needed metadata from the data collected on cruises. However there remained one piece missing to the automated system- the wordy part of the metadata that deals with information such as the attribute accuracy report, abstract and the process description. This information cannot be mined from the raw survey data. This paper illustrates how to generate a template from …


Modular Autonomous Biosampler (Mab)- A Prototype System For Distinct Biological Size-Class Sampling And Preservation, Arthur Trembanis, Craig Cary, Val E. Schmidt, Don Clarke, Tristan Crees, Eric Jackson Oct 2012

Modular Autonomous Biosampler (Mab)- A Prototype System For Distinct Biological Size-Class Sampling And Preservation, Arthur Trembanis, Craig Cary, Val E. Schmidt, Don Clarke, Tristan Crees, Eric Jackson

Center for Coastal and Ocean Mapping

Presently, there is a community wide deficiency in our ability to collect and preserve multiple size-class biologic samples across a broad spectrum of oceanographic platforms (e.g. AUVs, ROVs, and Ocean Observing System Nodes). This is particularly surprising in comparison to the level of instrumentation that now exists for acquiring physical and geophysical data (e.g. side-scan sonar, current profiles etc.), from these same platforms. We present our effort to develop a low-cost, high sample capacity modular,autonomous biological sampling device (MAB). The unit is designed for filtering and preserving 3 distinct biological size-classes (including bacteria), and is deployable in any aquatic setting …


Measurement Of Micro-Bathymetry With A Gopro Underwater Stereo Camera Pair, Val E. Schmidt, Yuri Rzhanov Oct 2012

Measurement Of Micro-Bathymetry With A Gopro Underwater Stereo Camera Pair, Val E. Schmidt, Yuri Rzhanov

Center for Coastal and Ocean Mapping

A GO-PRO underwater stereo camera kit has been used to measure the 3D topography (bathymetry) of a patch of seafloor producing a point cloud with a spatial data density of 15 measurements per 3 mm grid square and an standard deviation of less than 1 cm A GO-PRO camera is a fixed focus, 11 megapixel, still-frame (or 1080p high-definition video) camera, whose small form-factor and water-proof housing has made it popular with sports enthusiasts. A stereo camera kit is available providing a waterproof housing (to 61 m / 200 ft) for a pair of cameras. Measures of seafloor micro-bathymetrycapable of …


Chum: Chart Update Mashup, Briana M. Sullivan Oct 2012

Chum: Chart Update Mashup, Briana M. Sullivan

Center for Coastal and Ocean Mapping

The Chart Update Mash up (ChUM™) consists of various APIs/Technologies that when brought together allow for intuitive georeferenced visualization of the Critical Chart Updates published by the Office of Coast Survey (OCS). Each component of ChUM™ will be described in this paper with an explanation of how each piece works together to form ChUM™. Figure 1 shows the basic building blocks that make up ChUM™. At the base of the structure (in blue) is the data that OCS disseminates to the public via its website/web-services: Raster Nautical Charts, the CRIT data (critical corrections to the chart), and the Coast Pilot. …


U.S. Law Of The Sea Cruise To Map And Sample The Us Arctic Ocean Margin, Larry A. Mayer, Andy Armstrong Sep 2012

U.S. Law Of The Sea Cruise To Map And Sample The Us Arctic Ocean Margin, Larry A. Mayer, Andy Armstrong

Center for Coastal and Ocean Mapping

U.S. Law of the Sea cruise to map and sample the US Arctic Ocean margin

CRUISE HEALY 1202

August 25 to September 27, 2012

Barrow, AK to Dutch Harbor, AK


An Analysis Of Fast Photochemistry Over High Northern Latitudes During Spring And Summer Using In-Situ Observations From Arctas And Topse, J R. Olson, J H. Crawford, William H. Brune, J Mao, Xinrong Ren, A Fried, B Anderson, E C. Apel, M Beaver, D R. Blake, G Chen, John D. Crounse, Jack E. Dibb, Glenn Diskin, S R. Hall, L Gregory Huey, D Knapp, D Richter, D Riemer, J St. Clair, Kirk Ullman, J Walega, P Weibring, Andrew Weinheimer, Paul Wennberg, Armin Wisthaler Aug 2012

An Analysis Of Fast Photochemistry Over High Northern Latitudes During Spring And Summer Using In-Situ Observations From Arctas And Topse, J R. Olson, J H. Crawford, William H. Brune, J Mao, Xinrong Ren, A Fried, B Anderson, E C. Apel, M Beaver, D R. Blake, G Chen, John D. Crounse, Jack E. Dibb, Glenn Diskin, S R. Hall, L Gregory Huey, D Knapp, D Richter, D Riemer, J St. Clair, Kirk Ullman, J Walega, P Weibring, Andrew Weinheimer, Paul Wennberg, Armin Wisthaler

Earth Sciences

Observations of chemical constituents and meteorological quantities obtained during the two Arctic phases of the airborne campaign ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) are analyzed using an observationally constrained steady state box model. Measurements of OH and HO2 from the Penn State ATHOS instrument are compared to model predictions. Forty percent of OH measurements below 2 km are at the limit of detection during the spring phase (ARCTAS-A). While the median observed-to-calculated ratio is near one, both the scatter of observations and the model uncertainty for OH are at the magnitude of …


Sediment Mixing In The Tropical Pacific And Radiolarian Stratigraphy, Ted C. Moore Jr, Larry A. Mayer, Mitchell Lyle Aug 2012

Sediment Mixing In The Tropical Pacific And Radiolarian Stratigraphy, Ted C. Moore Jr, Larry A. Mayer, Mitchell Lyle

Center for Coastal and Ocean Mapping

The reworking of older radiolarian microfossils into near-surface sediments of the tropical Pacific has long been the source of confusion for the development of radiolarian stratigraphy and of puzzlement over the mechanism(s) that could effect such pervasive reworking. Widespread dissolution “pits” in the sediments of the tropical Pacific are believed to be associated with hydrothermal circulation cells in the older oceanic crust and are here linked to processes which expose older sections and inject older non-carbonate material into near-bottom waters. Discharging waters of these circulation cells tend to dissolve carbonate in near-surface sediments; thus, only the non-carbonate material (including radiolarians) …


Modeling Chemistry In And Above Snow At Summit, Greenland – Part 2: Impact Of Snowpack Chemistry On The Oxidation Capacity Of The Boundary Layer, J L. Thomas, Jack E. Dibb, L Gregory Huey, J Liao, D Tanner, Barry Lefer, R Von Glasow, J Stutz Jul 2012

Modeling Chemistry In And Above Snow At Summit, Greenland – Part 2: Impact Of Snowpack Chemistry On The Oxidation Capacity Of The Boundary Layer, J L. Thomas, Jack E. Dibb, L Gregory Huey, J Liao, D Tanner, Barry Lefer, R Von Glasow, J Stutz

Earth Sciences

The chemical composition of the boundary layer in snow covered regions is impacted by chemistry in the snowpack via uptake, processing, and emission of atmospheric trace gases. We use the coupled one-dimensional (1-D) snow chemistry and atmospheric boundary layer model MISTRA-SNOW to study the impact of snowpack chemistry on the oxidation capacity of the boundary layer. The model includes gas phase photochemistry and chemical reactions both in the interstitial air and the atmosphere. While it is acknowledged that the chemistry occurring at ice surfaces may consist of a true quasi-liquid layer and/or a concentrated brine layer, lack of additional knowledge …


R/V Kilo Moana Multibeam Echosounder System Review, Jonathan Beaudoin Jul 2012

R/V Kilo Moana Multibeam Echosounder System Review, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

No abstract provided.


On Importance Of Acoustic Backscatter Corrections For Texture-Based Seafloor Characterization, E Fakiris, Yuri Rzhanov, D Zoura Jul 2012

On Importance Of Acoustic Backscatter Corrections For Texture-Based Seafloor Characterization, E Fakiris, Yuri Rzhanov, D Zoura

Center for Coastal and Ocean Mapping

Seafloor segmentation and characterization based on local textural properties of acoustic backscatter has been a subject of research since 1980s due to the highly textured appearance of sonar images. The approach consists of subdivision of sonar image in a set of patches of certain size and calculation of a vector of features reflecting the patch texture. Advance of multibeam echosounders (MBES) allowed application of texture-based techniques to real geographical space, and predicted boundaries between acoustic facies became experimentally verifiable. However, acoustic return from uncalibrated MBES produces artifacts in backscatter mosaics, which in turn affects accuracy of delineation. Development of Geocoder …


The International Bathymetric Chart Of The Arctic Ocean (Ibcao) Version 3.0, Martin Jakobsson, Larry A. Mayer, Bernard Coakley, Julian A. Dowdeswell, Steve Forbes, Boris Fridman, Hanne Hodnesdal, Riko Noormets, Richard Pedersen, Michele Rebesco, Hans Werner Schenke, Yulia Zarayskaya, Daniela Accettella, Andy Armstrong, Robert M. Anderson, Paul Beinhoff, Angelo Camerlenghi, Ian Church, Margo Edwards, James V. Gardner, John K. Hall, Benjamin Hell, Ole Hestvik, Yngve Krisoffersen, Christian Marcussen, Rezwen Mohammad, David Mosher, Son V. Nghiem, Maria Teresa Pedrosa, Paola G. Travaglini, Pauline Weatherall Jun 2012

The International Bathymetric Chart Of The Arctic Ocean (Ibcao) Version 3.0, Martin Jakobsson, Larry A. Mayer, Bernard Coakley, Julian A. Dowdeswell, Steve Forbes, Boris Fridman, Hanne Hodnesdal, Riko Noormets, Richard Pedersen, Michele Rebesco, Hans Werner Schenke, Yulia Zarayskaya, Daniela Accettella, Andy Armstrong, Robert M. Anderson, Paul Beinhoff, Angelo Camerlenghi, Ian Church, Margo Edwards, James V. Gardner, John K. Hall, Benjamin Hell, Ole Hestvik, Yngve Krisoffersen, Christian Marcussen, Rezwen Mohammad, David Mosher, Son V. Nghiem, Maria Teresa Pedrosa, Paola G. Travaglini, Pauline Weatherall

Center for Coastal and Ocean Mapping

[1] The International Bathymetric Chart of the Arctic Ocean (IBCAO) released its first gridded bathymetric compilation in 1999. The IBCAO bathymetric portrayals have since supported a wide range of Arctic science activities, for example, by providing constraint for ocean circulation models and the means to define and formulate hypotheses about the geologic origin of Arctic undersea features. IBCAO Version 3.0 represents the largest improvement since 1999 taking advantage of new data sets collected by the circum-Arctic nations, opportunistic data collected from fishing vessels, data acquired from US Navy submarines and from research ships of various nations. Built using an improved …


Light Field And Water Clarity Simulation Of Natural Environments In Laboratory Conditions, Shachak Pe'eri, Glenn T. Shwaery Jun 2012

Light Field And Water Clarity Simulation Of Natural Environments In Laboratory Conditions, Shachak Pe'eri, Glenn T. Shwaery

Center for Coastal and Ocean Mapping

Simulation of natural oceanic conditions in a laboratory setting is a challenging task, especially when that environment can be miles away. We present an attempt to replicate the solar radiation expected at different latitudes with varying water clarity conditions up to 30 m in depth using a 2.5 m deep engineering tank at the University of New Hampshire. The goals of the study were: 1) to configure an underwater light source that produced an irradiance spectrum similar to natural daylight with the sun at zenith and at 60° under clear atmospheric conditions, and 2) to monitor water clarity as a …


Linking Goniometer Measurements To Hyperspectral And Multi-Sensor Imagery For Retrieval Of Beach Properties And Coastal Characterization, Charles M. Bachmann, Deric Gray, Andrei Abelev, William D. Philpot, Marcos J. Montes, Robert A. Fusina, Joseph Musser, Rong-Rong Li, Michael Vermillion, Geoffrey Smith, Daniel Korwan, Charlotte Snow, David W. Miller, Joan Gardner, Matt Sletten, Georgi Georgiev, Barry Truitt, Marcus Kilmon, Jon Sellars, Jason Woolard, Christopher Parrish, A. Schwarzschild May 2012

Linking Goniometer Measurements To Hyperspectral And Multi-Sensor Imagery For Retrieval Of Beach Properties And Coastal Characterization, Charles M. Bachmann, Deric Gray, Andrei Abelev, William D. Philpot, Marcos J. Montes, Robert A. Fusina, Joseph Musser, Rong-Rong Li, Michael Vermillion, Geoffrey Smith, Daniel Korwan, Charlotte Snow, David W. Miller, Joan Gardner, Matt Sletten, Georgi Georgiev, Barry Truitt, Marcus Kilmon, Jon Sellars, Jason Woolard, Christopher Parrish, A. Schwarzschild

Center for Coastal and Ocean Mapping

In June 2011, a multi-sensor airborne remote sensing campaign was flown at the Virginia Coast Reserve Long Term Ecological Research site with coordinated ground and water calibration and validation (cal/val) measurements. Remote sensing imagery acquired during the ten day exercise included hyperspectral imagery (CASI-1500), topographic LiDAR, and thermal infra-red imagery, all simultaneously from the same aircraft. Airborne synthetic aperture radar (SAR) data acquisition for a smaller subset of sites occurred in September 2011 (VCR'11). Focus areas for VCR'11 were properties of beaches and tidal flats and barrier island vegetation and, in the water column, shallow water bathymetry. On land, cal/val …


Develping A Methodology For The Mapping And Characterization Of The Nigerian Coastline Using Remote Sensing, Olumide Fadahunsi, Shachak Pe'eri, Lee Alexander, Christopher Parrish May 2012

Develping A Methodology For The Mapping And Characterization Of The Nigerian Coastline Using Remote Sensing, Olumide Fadahunsi, Shachak Pe'eri, Lee Alexander, Christopher Parrish

Center for Coastal and Ocean Mapping

Coastline delineation is important in maritime boundary determination, as well as for analyzing coastline change rates due to coastal erosion, sea level change, storms, and other causes. Coastline change rate estimates depend on the uncertainty of the current and historical coastlines used in the analysis, which, in turn, depend on the surveying technologies and techniques that were originally used. Current techniques for coastline mapping include photogrammetric delineation using tide-coordinated aerial imagery. However, in many developing countries, the charted coastlines may have been inadequately and inconsistently mapped largely due to inadequate resources. This paper describes the use of an automated technique …


Development Of A Geo-Spatial Analysis Methodology For Assessing The Adequacy Of Hydrographic Surveying And Nautical Charts, Chukwuma Azuike, Shachak Pe'eri, Lee Alexander, Christopher Parrish, Andy Armstrong May 2012

Development Of A Geo-Spatial Analysis Methodology For Assessing The Adequacy Of Hydrographic Surveying And Nautical Charts, Chukwuma Azuike, Shachak Pe'eri, Lee Alexander, Christopher Parrish, Andy Armstrong

Center for Coastal and Ocean Mapping

IHO Publication C-55 (Status of Hydrographic Surveying and Nautical Charting Worldwide) contains information about the progress of hydrographic surveying and nautical charting for a country with navigable waters under its jurisdiction. Listed primarily as percent coverage, it is difficult to use this information to determine: 1) if the current level of surveying or charting is adequate or in need of action, or 2) can be used to compare different locations. An analysis and assessment methodology has been developed to assess the adequacy hydrographic surveying and nautical charting coverage. Indications of chart adequacy and completeness as depicted on current charts or …


Developing A Gis-Database And Risk Index For Potentially Polluting Marine Sites, Giuseppe Masetti, Brian R. Calder, Lee Alexander May 2012

Developing A Gis-Database And Risk Index For Potentially Polluting Marine Sites, Giuseppe Masetti, Brian R. Calder, Lee Alexander

Center for Coastal and Ocean Mapping

The increasing availability of geospatial marine data provides an opportunity for hydrographic offices to contribute to the identification of “Potentially Polluting Marine Sites” (PPMS). These include shipwrecks, oil rigs, pipelines, and dumping areas. To adequately assess the environmental risk of these sites, relevant information must be collected and converted into a multi-scale geodatabase suitable for site inventory and geo-spatial analysis. In addition, a Risk Index – representing an assessment of the magnitude of risk associated with any site – can be derived to determine the potential impacts of these PPMS. However, the successful collection and integration of PPMS information requires …


Usage Of Videomosaic For Computer Aided Analysis Of North Sea Hard Bottom Underwater Video For Baseline Study Of Offshore Windmill Park, Aleksej Shashkov, Thomas Dahlgren, Marie-Lise Schlappy, Yuri Rzhanov May 2012

Usage Of Videomosaic For Computer Aided Analysis Of North Sea Hard Bottom Underwater Video For Baseline Study Of Offshore Windmill Park, Aleksej Shashkov, Thomas Dahlgren, Marie-Lise Schlappy, Yuri Rzhanov

Center for Coastal and Ocean Mapping

Windmill park on the open North Sea coast at Hävsul area in Norway is one of the first in the world to be build on such extreme high-energy coast. To determine possible environmental impact of this project, baseline study was performed in 2010-2011. Two areas, impacted (area where windmill park is planned to be build) and reference were chosen. For hard bottoms work class ROV was used to take underwater video, as no traditional sampling methods are suitable for such environment and depths. The system was equipped with powerful (400 Watt) xenon lights, USBL navigation and HDTV color camera. For …


Establishing A Multibeam Sonar Evaluation Test Bed Near Sidney, British Columbia, Rob Hare, Clay Whittaker, J.E. Hughes Clarke, Jonathan Beaudoin May 2012

Establishing A Multibeam Sonar Evaluation Test Bed Near Sidney, British Columbia, Rob Hare, Clay Whittaker, J.E. Hughes Clarke, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

The Canadian Hydrographic Service (CHS), Naval Oceanographic Office (NAVOCEANO) and the Ocean Mapping Group of the University of New Brunswick (OMG) collaborated on establishing a multibeam sonar test bed in the vicinity of the Institute of Ocean Sciences in Sidney, British Columbia Canada. This paper describes the purpose of the sonar evaluation test bed, the trials and tribulations of two foreign governments collaborating on projects of mutual interest, the evaluation areas and their characteristics for sonar testing, and sample results of sonar evaluations using this test bed. Some target detection comparisons of several systems over a range of artificial sonar …


Beyond The Chart: The Use Of Satellite Remote Sensing For Assessing The Adequacy And Completeness Information, Shachak Pe'eri, Chukwuma Azuike, Lee Alexander, Christopher Parrish, Andy Armstrong May 2012

Beyond The Chart: The Use Of Satellite Remote Sensing For Assessing The Adequacy And Completeness Information, Shachak Pe'eri, Chukwuma Azuike, Lee Alexander, Christopher Parrish, Andy Armstrong

Center for Coastal and Ocean Mapping

Chart adequacy and completeness information consists of the symbols, abbreviations and warnings used to inform mariners of the level of confidence that should be given to data on a nautical chart. This information is derived both from the nautical chart and sailing directions. However, analysis based solely on these datasets is limited without access to the sources (e.g., smooth sheets). Publically-available, multi-spectral satellite imagery and published algorithms can be used to derive estimates of the relative bathymetry in shallow, clear waters. In this study, we evaluate the potential of these methods for supplementing the procedure to assess the adequacy of …


The Impact Of Sea State Condition On Airborne Lidar Bathymetry Measurements, Torbjorn Karlsson, Andreas Axelsson, Shachak Pe'eri May 2012

The Impact Of Sea State Condition On Airborne Lidar Bathymetry Measurements, Torbjorn Karlsson, Andreas Axelsson, Shachak Pe'eri

Center for Coastal and Ocean Mapping

Due to a large number of available Airborne Lidar Bathymetry (ALB) survey datasets and scheduled future surveys, there is a growing need from coastal mapping communities to estimate the accuracy of ALB as a function of the survey system and environmental conditions. Knowledge of ALB accuracy can also be used to evaluate the quality of products derived from ALB surveying. This paper presents theoretical and experimental results focused on the relationship between sea surface conditions and the accuracy of ALB measurements. The simulated environmental conditions were defined according to the typical conditions under which successful ALB surveys can be conducted. …


Seafloor Characterization For Trawlability Using The Simrad Me70 Multibeam Echosounder In The Gulf Of Alaska, Jodi L. Pirtle, Thomas C. Weber, Chris Rooper, Christopher D. Wilson, Brian R. Calder May 2012

Seafloor Characterization For Trawlability Using The Simrad Me70 Multibeam Echosounder In The Gulf Of Alaska, Jodi L. Pirtle, Thomas C. Weber, Chris Rooper, Christopher D. Wilson, Brian R. Calder

Center for Coastal and Ocean Mapping

No abstract provided.


The Carrington Event Not Observed In Most Ice Core Nitrate Records, E W. Wolff, M Bigler, M. A. J. Curran, Jack E. Dibb, M M. Frey, M Legrand, J R. Mcconnell Apr 2012

The Carrington Event Not Observed In Most Ice Core Nitrate Records, E W. Wolff, M Bigler, M. A. J. Curran, Jack E. Dibb, M M. Frey, M Legrand, J R. Mcconnell

Earth Sciences

The Carrington Event of 1859 is considered to be among the largest space weather events of the last 150 years. We show that only one out of 14 well-resolved ice core records from Greenland and Antarctica has a nitrate spike dated to 1859. No sharp spikes are observed in the Antarctic cores studied here. In Greenland numerous spikes are observed in the 40 years surrounding 1859, but where other chemistry was measured, all large spikes have the unequivocal signal, including co-located spikes in ammonium, formate, black carbon and vanillic acid, of biomass burning plumes. It seems certain that most spikes …


Extracting More Data From Lidar In Forested Areas By Analyzing Waveform Shape, Thomas Adams, Peter Beets, Christopher Parrish Mar 2012

Extracting More Data From Lidar In Forested Areas By Analyzing Waveform Shape, Thomas Adams, Peter Beets, Christopher Parrish

Center for Coastal and Ocean Mapping

Light Detection And Ranging (LiDAR) in forested areas is used for constructing Digital Terrain Models (DTMs), estimating biomass carbon and timber volume and estimating foliage distribution as an indicator of tree growth and health. All of these purposes are hindered by the inability to distinguish the source of returns as foliage, stems, understorey and the ground except by their relative positions. The ability to separate these returns would improve all analyses significantly. Furthermore, waveform metrics providing information on foliage density could improve forest health and growth estimates. In this study, the potential to use waveform LiDAR was investigated. Aerial waveform …


Public Knowledge About Polar Regions Increases While Concerns Remain Unchanged, Lawrence C. Hamilton, Matthew J. Cutler, Andrew P. Schaefer Feb 2012

Public Knowledge About Polar Regions Increases While Concerns Remain Unchanged, Lawrence C. Hamilton, Matthew J. Cutler, Andrew P. Schaefer

The Carsey School of Public Policy at the Scholars' Repository

The authors of this brief conduct the first comparative analysis of the polar questions that were part of the National Opinion Research Center's 2006 and 2010 General Social Survey. Developed by scientists at the National Science Foundation's Office of Polar Programs, these questions covered topics such as climate change, melting ice and rising sea levels, and species extinction. The authors report that the public's knowledge about the north and south polar regions significantly improved between 2006 and 2010--before and after the International Polar Year. In addition, respondents who know more about science in general, and polar facts specifically, tend to …