Oceanography and Atmospheric Sciences and Meteorology Commons^™

The High-Frequency Backscattering Angular Response Of Gassy Sediments: Model/Data Comparison From The Eel River Margin, California, Luciano E. Fonseca, Larry A. Mayer, Dan Orange, Neal Driscoll

Center for Coastal and Ocean Mapping

A model for the high-frequency backscatter angular response of gassy sediments is proposed. For the interface backscatter contribution we adopted the model developed by Jackson et al. @J. Acoust. Soc. Am. 79, 1410–1422 ~1986!#, but added modifications to accommodate gas bubbles. The model parameters that are affected by gas content are the density ratio, the sound speed ratio, and the loss parameter. For the volume backscatter contribution we developed a model based on the presence and distribution of gas in the sediment. We treat the bubbles as individual discrete scatterers that sum to the total bubble contribution. This total bubble …

The Compilation And Analysis Of Data Relevant To A U.S. Claim Under United Nations Law Of The Sea Article 76: A Preliminary Report, Larry A. Mayer, Martin Jakobsson, Andy Armstrong

Center for Coastal and Ocean Mapping

No abstract provided.

Studies Of Peroxyacetyl Nitrate (Pan) And Its Interaction With The Snowpack At Summit, Greenland, Kevin M. Ford, Bradley M. Campbell, P B. Shepson, Steven B. Bertman, R E. Honrath, Matthew C. Peterson, Jack E. Dibb

Earth Sciences

Peroxyacetyl nitrate (PAN) was measured in ambient and snowpack interstitial air at Summit, Greenland, in June and July of 1998 and 1999 and at a rural/forest site in the Keewenaw Peninsula of Michigan in January of 1999. At Summit, we found that PAN typically represented between 30 and 60% of NO_y. In the summer of 1999, a significant diel variation in both PAN/NO_y and NO_x/NO_y was observed, but this was much less pronounced in 1998. Experiments during SNOW99 near Houghton, Michigan, indicated that PAN undergoes weak uptake onto snow grain surfaces. At Summit, we …

Long Range Forecast Possibilities For X-Band Radar Construction On Shemya, Brian K. Schroeder

Theses and Dissertations

Current moisture initialization sources lack the spatial and temporal resolution required for mesoscale moisture forecast accuracy critical for military operations. The Global Positioning System (GPS) satellite constellation provides an opportunity to extract accurate moisture observations based on the refraction of the GPS signal through the troposphere. GPS-derived precipitable water (PW) from two different research areas was independently compared with the Air Force Weather Agency s (AFWA's) MM5 PW model output. Results were concurrent with similar studies comparing GPS-derived PW with numerical weather models. The mean correlation in CONUS was 92.5%, while in Alaska it was 72.8%. Mean model biases were …

Hypsometry And Volume Of The Arctic Ocean And Its Constituent Seas, Martin Jakobsson

Center for Coastal and Ocean Mapping

This paper presents an analysis of the Arctic Ocean and its constituent seas for seafloor area distribution versus depth and ocean volume. The bathymetry from the International Bathymetric Chart of the Arctic Ocean (IBCAO) is used together with limits defining this ocean and its constituent seas from the International Hydrographic Organization (IHO) as well as redefined limits constructed to confine the seas to the shallow shelves. IBCAO is a bathymetric grid model with a resolution of 2.5 x 2.5 km, which significantly improved the portrayal of the Arctic Ocean seafloor through incorporation of newly released bathymetric data including echo soundings …

3d Visualization Of Coral Reef Habitat, Brian K. Walker, Richard E. Dodge

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

A bathymetric survey was recently conducted in Southeast Florida (Broward County) during April 2001 using the Laser Airborne Depth Sounder (LADS) system. This four-meter resolution survey encompassed from North Dade County, through the length of Broward County coastline, to south Palm Beach County (approximately 43 km) and from the shore eastward to depths of approximately 40 m (2.5-3.5 km offshore). This georeferenced data was sun shaded at various angles and azimuths and draped with a NOAA NAPP 1:24,000 georeferenced air photograph mosaic. The model was zoomed and tipped to the desired orientations and processed into three-dimensional perspectives. Two views, slightly …

Humidity And Temperature Boundaries For Biofilm Formation In Yucca Mountain, Terry Ann Else, Penny S. Amy, James Jay, Amy J. Smiecinski

Publications (YM)

To determine the long-term success of the recommended Yucca Mountain high-level nuclear waste repository, studies of bacterial colonization and biofilm development are needed. Bacteria involved in microbially-influenced corrosion and degradation are known to form biofilms with the potential to impact the integrity of repository packaging and structural materials. Temperature and humidity are environmental factors that can greatly affect biofilm formation. Therefore, it is necessary to determine the temperature and humidity conditions that affect biofilm formation. Microcosms, which simulated the repository environment of Yucca Mountain, were placed at temperatures ranging from 30° C to 70° C and in relative humidities ranging …

Geometric And Radiometric Correction Of Multibeam Backscatter Derived From Reson 8101 Systems, Jonathan Beaudoin, J.E. Hughes Clarke, Edward J. Van Den Ameele, James V. Gardner

Center for Coastal and Ocean Mapping

A common by-product of multibeam surveys is a measure of the backscattered acoustic intensity from the seafloor. These data are of immense interest to geologists and geoscientists since maps of the acoustic backscatter strength can be used to infer physical properties of the sea bottom, such as impedance, roughness and volume inhomogeneity. Before such maps can be created from multibeam acoustic backscatter data, however, two tasks must be performed.

1. The data must be geographically registered using the bathymetric profile collected by the multibeam (which accounts for full orientation and refraction), as opposed to using the traditional flat-seafloor assumption. This …

Pesticide Ground Water Monitoring Project Phase Viii, K. F. Steele, M. A. Nelson, T. Nichols, R. Polite, H. D. Scott, Charles Armstrong

Arkansas Water Resources Center Technical Reports

During Phase VIII monitoring (March 24, 2000 to June 30, 2001 ), 86 samples were collected from 77 new wells and 9 samples were collected from wells with previous detectable herbicide.

Three Years And Counting: What’S New With The Drought Monitor, Mark D. Svoboda, Michael J. Hayes, Rich J. Tinker

National Drought Mitigation Center: Faculty Publications

Operational since late summer 1999, the Drought Monitor (http://drought.unl.edu/monitor/) has refused to remain static. This unique weekly product attempts to make an assessment of current drought conditions in the contiguous United States, Hawaii, Alaska, and Puerto Rico. Four entities now share in authoring the map: the National Drought Mitigation Center (NDMC), Climate Prediction Center (CPC), United States Department of Agriculture (USDA), and National Climatic Data Center (NCDC).
The Drought Monitor effort has led to the development of new products and has reinforced the need for improvement and support of existing climate networks critical to monitoring our nation’s climate. One of …

Shouldn’T Snowpacks Be Sources Of Monocarboxylic Acids?, Jack E. Dibb, Matthew Arsenault

Earth Sciences

We report the first measurements of the mixing ratios of acetic (CH₃COOH) and formic (HCOOH) acids in the air filling the pore spaces of the snowpacks (firn air) at Summit, Greenland and South Pole. Both monocarboxylic acids were present at levels well above 1 ppbv throughout the upper 35 cm of the snowpack at Summit. Maximum mixing ratios in Summit firn air reached nearly 8 ppbv CH₃COOH and 6 ppbv HCOOH. At South Pole the mixing ratios of these acids in the top 35 cm of firn air were also generally >1 ppbv, though their maximums …

Zooplankton, Tracey Sutton, Scott E. Burghart

Marine & Environmental Sciences Faculty Reports

No abstract provided.

Artificial Keys To The Genera Of Living Stalked Crinoids (Echinodermata), Michel Roux, Charles G. Messing, Nadia Améziane

Marine & Environmental Sciences Faculty Articles

Two practical, illustrated, dichotomous keys to the 29 genera of living stalked crinoids are provided: one for entire animals and one for stalk ossicles and fragments. These are accompanied by (1) an overview of taxonomically important morphology, and (2) an alphabetical list by family and genus of the ∼95 nominal living species and their distribution by region. This is the first compilation of such data for all living stalked crinoids since Carpenter (1884) recognized 27 species in six genera in his monograph based on the H.M.S. CHALLENGER Expedition collection.

Oceanic Transport And Life History Of The Tropical Western Atlantic Opossum Pipefish, Microphis Brachyurus Lineatus, Sarah Frias-Torres

Theses and Dissertations

The opossum pipefish, Microphis brachyurus lineatus, is a tropical migratory syngnathid. Adults live and breed in freshwater tributaries in specific emergent vegetative habitats. Juveniles associate with pelagic Sargassum in the tropical western Atlantic. Reproduction occurs during the wet season (May-November). Juvenile recruitment occurs during the dry season (December-April). The objective of this dissertation is to study the east Florida breeding population in the freshwater tributaries of the Indian River Lagoon and focus on: 1) Larval drift to the Gulf Stream and, 2) recruitment of pelagic juveniles from the Gulf Stream onto the freshwater breeding habitat. Pouch released larvae face sharp …

Haptic Interface For Center Of Workspace Interaction, Rick Komerska, Colin Ware, Matt D. Plumlee

Center for Coastal and Ocean Mapping

We build upon a new interaction style for 3D interfaces, called the center of workspace interaction. This style of interaction is defined with respect to a central fixed point in 3D space, conceptually within arm's length of the user. For demonstration, we show a haptically enabled fish tank VR that utilizes a set of interaction widgets to support rapid navigation within a large virtual space. The fish tank VR refers to the creation of a small but high quality virtual reality that combines a number of technologies, such as head-tracking and stereo glasses, to their mutual advantage

The Drought Monitor, Mark D. Svoboda, Doug Lecomte, Mike Hayes, Richard Heim, Karin Gleason, Jim Angel, Brad Rippey, Rich Tinker, Mike Palecki, David Stooksbury, David Miskus, Scott Stephens

National Drought Mitigation Center: Faculty Publications

There is a need for improved drought monitoring and assessment methods in the United States. Drought is the most costly natural disaster [Federal Emergency Management Agancy (FEMA 1995; Wilhite 2000)], but it is often neglected by developers of assessment and forecast products. Drought is more nebulous than other disasters and does not lend itself to traditional assessments or forecast methods. Its relatively slow onset and the complexity of its impacts are reasons for the new assessment methodology. Improvements in drought monitoring and forecasting techniques will allow for better preparation, lead to better management practices, and reduce the vulnerability of society …

Sea Stewards: A Volunteer Ecological Monitoring Program, Nicole D. Fogarty, Mary Enstrom

Marine & Environmental Sciences Faculty Reports

No abstract provided.

An Examination Of Anomalously Low Column Ozone In The Southern Hemisphere Midlatitudes During 1997, Eugene C. Cordero, Terrence R. Nathan

Faculty Publications, Meteorology and Climate Science

[1] Observations from both ground-based and satellite instruments show record low column ozone abundance between 20°S and 40°S during 1997. The 1997 monthly averaged column ozone from the Total Ozone Mapping Spectrometer (TOMS) is up to 25 Dobson units (DU) lower than the TOMS climatological mean (1979–1996) and up to 20 DU below the previous record low values. Observations from the Halogen Occultation Experiment show that below average ozone concentrations during 1997 were confined primarily to the lower stratosphere. Residual circulation statistics calculated from the United Kingdom Meteorological Office temperature analyses indicate that circulation anomalies during 1997 can account for …

Fisheries Research Report No. 134, Vol 1 - Towards An Assessment Of The Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands, F J. Webster, C J. Dibden, C F. Chubb

Fisheries Research Reports

The State Territorial Waters surrounding the Abrolhos Islands are gazetted as a Fish Habitat Protection Area and vested with the Minister for Fisheries under the Fish Resources Management Act 1994. Three Fisheries Management Papers have identified management priorities for the marine environment at the Abrolhos Islands:

• Management of the Houtman Abrolhos System
• Aquaculture Plan for the Houtman Abrolhos Islands
• Sustainable Tourism Plan for the Houtman Abrolhos Islands.

These plans and other national and international obligations to examine the effect of extractive and non-extractive anthropogenic activities on marine habitats (eg. Environment Protection and Biodiversity Conservation Act 1999) led to …

Fish Assemblages Associated With Artificial Reefs Of Concrete Aggregates Or Quarry Stone Offshore Miami Beach, Florida, Usa, Brian K. Walker, Bruce Henderson, Richard E. Spieler

Marine & Environmental Sciences Faculty Articles

Few studies have compared the suitability of different artificial reef construction materials in terms of their efficacy in acquiring diverse faunal assemblages. We compared the fishes associated with 12 co-located reefs constructed of limestone quarry boulders, concrete-gravel aggregate, or concrete-tire aggregate (four of each substrate) in 7 m of water, 200 m offshore Miami Beach, Florida, USA. All 12 reefs were deployed 100 m apart the same day in two lines of six. The four quarry stone reefs consist of a pile of 50 boulders each. The remaining eight reefs, of concrete-gravel aggregate and concrete-tire aggregate, were each constructed with …

Spring 2002, Nsu Oceanographic Center

Currents

No abstract provided.

Vertical Distributions Of Zooplankton At The Mouth Of Chesapeake Bay And Calibration Of Backscatter From An Acoustic Doppler Current Profiler, Arthur Keith Jenkins

Biological Sciences Theses & Dissertations

This study investigated the physical factors influencing the vertical distribution of zooplankton at the mouth of the Chesapeake Bay and attempted to derive biological data from acoustic Doppler current profiler (ADCP) backscatter. A single site was occupied in the North Channel at the mouth of Chesapeake Bay (37° 04' N, 75° 58' W) from 17.0–19.7 November 1999. Temperature, salinity, fluorescence, light transmission, current velocity and backscatter were measured throughout the sampling period. Plankton samples were collected every hour from 3.5, 7.5, and 11.5 m.

We found little association between ADCP backscatter and plankton concentrations, but stronger correlations between backscatter and …

Quantification Of The Effects Of Data Denial And Limitation In Mm5 Initialization On Forecast Accuracy, Robert W. Evans

Theses and Dissertations

The current hub-and-spoke network in the European Theater is made up of locations built and organized around a Cold War threat. The threat of large-scale attrition warfare seems to have passed, and the threat of multiple, smaller scale contingencies has placed greater demands on the US military's ability to transport equipment and personnel to multiple locations simultaneously. This research effort utilizes a Multiple Objective Linear Programming (MOLP) model to analyze optimal hub locations in USEUCOM. The model used to analyze the network was developed in Microsoft Excel and followed MOLP techniques to determine the trade-offs between the two constructs of …

The Horizontal Extent Of Lightning Based On Altitude And Atmospheric Temperature, David R. Vollmer

Theses and Dissertations

Due to multiple factors, including an increase in military operations tempo and the improved resolution of meteorological models, demand for access to customized aviation weather products has increased exponentially. This has given rise to a need for a multi-purpose interactive aviation weather product generation software solution. This software solution must be platform-independent, multiple data source access configurable, robust, extensible or upgradeable, user-friendly, and an improvement over current visualization applications used in the operational military aviation weather community. This thesis determines whether Unidata MetApps meets these criteria. A software reuse and component-based engineering approach was taken in this thesis. Two experimental …

Gps-Derived Precipitable Water Compared With The Air Force Weather Agency's Mm5 Model Output, Patricia A. Vollmer

Theses and Dissertations

Lightning poses a threat to aircraft in flight. To mitigate this threat, the U.S. Air Force requested a study of lightning distances. Three-Dimensional lightning data were examined for this study, spanning 1 March 1997 to 31 May 2001 and obtained from the Lightning Detection and Ranging System (LDAR) at the Kennedy Space Center, FL. The LDAR data points were first grouped into lightning flashes and branches using spatial and temporal criteria. Rawinsonde data were vertically interpolated to determine the temperature at the flash source point and each branch end point. The horizontal distance from flash sources to branch end was …

Near-Real-Time Applications Of A Mesoscale Analysis System To Complex Terrain, Steven M. Lazarus, Carol M. Ciliberti, John D. Horel, Keith A. Brewer

Aeronautics Faculty Publications

Several mesoscale data analysis systems are reviewed, of which one is then adapted and applied to the complex terrain of northwest Utah and the western United States. The analysis system relies on the simple, but computationally efficient, successive correction methodology. Near-real-time three-dimensional mesoscale analyses are produced hourly over northwest Utah at 1-km horizontal resolution while analyses are produced every 15 min for surface fields over northwest Utah and the western United States. Surface analyses over the western United States are also generated at 0000 and 1200 UTC to help to initialize 36- h mesoscale model forecasts. Comparisons between the 1-km …

Suitability Of Unidata Metapps For Incorporation In Platform-Independent User-Customized Aviation Weather Products Generation Software, Harmen P. Visser

Theses and Dissertations

The Air Force Combat Climatology Center (AFCCC) is tasked to provide long-range seasonal forecasts for worldwide locations. Currently, the best long-range temperature forecasts the weather community has are the climatological standard normals. This study creates a stepping-stone into the solution of long-range forecasting by finding a process to predict temperatures better than those using climatological standard normals or simple frequency distributions of occurrences. Northern Hemispheric teleconnection indices and the standardized Southern Oscillation index are statistically compared to three-month summed Heating Degree Days (HDDs) and Cooling Degree Days (CDDs) at 14 U.S. locations. First, linear regression was accomplished. The results showed …

Extratropical Transition Of Southwest Pacific Tropical Cyclones. Part I: Climatology And Mean Structure Changes, Mark R. Sinclair

Applied Aviation Sciences - Prescott

A database of tropical cyclone best track and intensity information for the southwest Pacific Ocean basin is used to construct a 28-year climatology for tropical cyclones that move into middle latitudes. Of the nine or so tropicalcyclones that form each year, an average of about three can be expected to migrate south of 35°S, with the greatest fraction in March. Storms entering the Tasman Sea west of New Zealand (NZ) move almost due south on average and retain greater intensity than those to the east of NZ, where storms decay quickly while moving rapidly away to the southeast. Storms east …

Estimation Of Atmospheric Precipitable Water Using The Global Positioning System, David A. Garay

Theses and Dissertations

This research focuses on using the Global Positioning System (GPS) for atmospheric precipitable water (PW) estimation. Water vapor, measured in terms of PW, plays a crucial role in atmospheric processes and short-term weather forecasting. Traditional methodologies for measuring atmospheric water vapor distributions have known inadequacies, resulting in the motivation to gain good water vapor characterization via GPS. The ability to accurately forecast cloud formation and other weather phenomenon is critical, especially in the case of military operations. Using a network of GPS receivers, it is possible to estimate precipitable water throughout the network region with better accuracy than traditional methods …

Verification Of Mm5 Cloud Microphysics Schemes For East Asia, Dean J. Carter

Theses and Dissertations

Using the 3-Dimensional Variational Analysis data assimilation scheme and the (MM5), input observations were denied in three different categories: total, upper air, and surface observation denial. Two control groups were run using all available data as received by AFWA. The main control group used a 6 hours old first guess as a baseline. The data denied test cases and the secondary control group used a 30-hour old first guess because it was not possible to deny data from the first guess. The secondary control group was used to estimate errors resulting from the use of different first guess forecasts between …