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Articles 11521 - 11550 of 14144

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Fisheries Research Report No. 119 - Final Report, Frdc Project 95/037: The Biology And Stock Assessment Of The Tropical Sardine, Sardinella Lemuru, Off The Mid-West Coast Of Western Australia, Daniel J. Gaughan, Ronald W. Mitchell May 2000

Fisheries Research Report No. 119 - Final Report, Frdc Project 95/037: The Biology And Stock Assessment Of The Tropical Sardine, Sardinella Lemuru, Off The Mid-West Coast Of Western Australia, Daniel J. Gaughan, Ronald W. Mitchell

Fisheries Research Reports

Exploratory fishing for the tropical sardine, Sardinella lemuru, offshore of Geraldton on the midwest coast of Western Australia in the early 1990s, led to the establishment of a developmental purse seine fishery in this region. This fishery showed potential for substantial expansion, but as there was no information on S. lemuru in WA there was a need to undertake research during the developmental period. The biology and fishery for S. lemuru in WA were therefore investigated over a three year period between July 1995 and June 1998 with the aim of providing stock assessment advice.

The biology of S. lemuru …


A Conceptual Hydrogeological Model For The Lake Warden Recovery Catchments Esperance, Western Australia, R Short May 2000

A Conceptual Hydrogeological Model For The Lake Warden Recovery Catchments Esperance, Western Australia, R Short

Resource management technical reports

The National Land and Water Resource Audit (NLWRA), has identified Dryland Salinity as one of seven major themes for an audit of the nation’s land, water, vegetation and natural resource management. Within this theme, Project 3 has been developed to investigate a key catchment type and how management scenarios will impact on dryland salinity processes. The Lake Warden catchments have been chosen as one of four catchment water balance studies to be undertaken nationally. The catchment water balance analysis will be undertaken using numerical modelling by the CSIRO, Division of Land and Water.


Using The Spi To Identify Drought, C. T. Agnew May 2000

Using The Spi To Identify Drought, C. T. Agnew

Drought Network News (1994–2001)

This article was written in response to the recent analysis of drought in Turkey by Komuscu (1999). The study showed the relationship between drought duration, drought frequency, and drought time scale using the Standardized Precipitation Index (SPI).


Announcements: Spring 2000 May 2000

Announcements: Spring 2000

Drought Network News (1994–2001)

Contents:

Droughts: A Global Assessment

Proceedings of the National Workshop on Dynamic Crop Simulation Modeling for Agrometeorological Advisory Services

Central and Eastern European Workshop on Drought Mitigation

11th Global Warming International Conference and Expo

GLOBE Data Set


Revisiting The Spi: Clarifying The Process, Michael J. Hayes May 2000

Revisiting The Spi: Clarifying The Process, Michael J. Hayes

Drought Network News (1994–2001)

The number of applications using the Standardized Precipitation Index (SPI) around the world continues to increase (e.g., Agnew, pp. 6–12 of this newsletter, and Komuscu 1999). However, there are relatively few publications explaining the SPI, and occasional misconceptions about the index have occurred.

When the SPI was first developed by McKee et al. (1993, 1995), it was meant to address some of the limitations that exist within the Palmer Drought Index (PDI). These first publications were relatively simple introductions of the SPI to the scientific community, appearing in the Proceedings of the Eighth and Ninth Applied Climatology Conferences, respectively, sponsored …


Characteristics Of Drought In Kerala, India, K. K. Nathan May 2000

Characteristics Of Drought In Kerala, India, K. K. Nathan

Drought Network News (1994–2001)

Kerala state in India, which is the first area of the country to experience the southwest monsoon, has a moist and wet climate. Kerala is in the extreme southwestern part of the Indian subcontinent; it borders Karnataka state in the north, Tamil Nadu in the east, and the Arabian Sea in the west (Figure 1). The entire state is one of the 35 meteorological subdivisions in India.

Kerala’s climate is tropical monsoon and tropical savanna, according to Koppen’s climatic classification (Figure 1). The state normally experiences excessive seasonal rainfall, with hot summers (except in the extreme southern districts like Trivandrum, …


Diagrams Based On Structured Object Perception, Pourang Irani, Colin Ware May 2000

Diagrams Based On Structured Object Perception, Pourang Irani, Colin Ware

Center for Coastal and Ocean Mapping

Most diagrams, particularly those used in software engineering, are line drawings consisting of nodes drawn as rectangles or circles, and edges drawn as lines linking them. In the present paper we review some of the literature on human perception to develop guidelines for effective diagram drawing. Particular attention is paid to structural object recognition theory. According to this theory as objects are perceived they are decomposed into 3D set of primitives called geons, together with the skeleton structure connecting them. We present a set of guidelines for drawing variations on node-link diagrams using geon-like primitives, and provide some examples. Results …


An Examination Of Gasoline Pollutants From Two-Cycle Marine Engines Within Lake Mead National Recreation Area, Brian Carter May 2000

An Examination Of Gasoline Pollutants From Two-Cycle Marine Engines Within Lake Mead National Recreation Area, Brian Carter

UNLV Theses, Dissertations, Professional Papers, and Capstones

Jet skis are a very popular "toy" to have in the United States. They account for almost a third of all boat sales, and their numbers are growing rapidly. Unfortunately jet skis use two-cycle engines that pollute at unacceptable levels. Jet ski motors can emit up to 25% of its fuel right back into the water. This alarmed me and I wanted to take a deeper look into how bad jet skis pollute Las Vegas' primary water source. Lake Mead. I looked into how a two-cycle engine differs from a regular engine and I looked at the actual pollutants a …


Re-Evaluation Of Wave Transmission Coefficients For Submerged Breakwater Physical Models, Harry Charles Friebel May 2000

Re-Evaluation Of Wave Transmission Coefficients For Submerged Breakwater Physical Models, Harry Charles Friebel

Theses and Dissertations

Increasing interest in utilizing submerged breakwaters and artificial reefs for shoreline stabilization requires accurate models and relationships for predicting wave attenuation. The objective of this paper is to develop an empirical model as an improvement to existing wave transmission models. This will provide the required design criteria for use in future submerged breakwater designs. An extensive study of existing literature on submerged breakwaters and associated wave attenuation was performed, followed by a detailed statistical analysis of existing data sets to determine an alternate model for the wave transmission coefficient. A total of five data sets from physical model studies were …


The Rural Towns Program : Groundwater Modelling : The Merredin Catchment, J Matta May 2000

The Rural Towns Program : Groundwater Modelling : The Merredin Catchment, J Matta

Resource management technical reports

Agriculture Western Australia (Agwest), as part of the Rural Towns Program, was engaged to test the application of a groundwater model for potential future management options against salinity for the Merredin townsite. This report illustrates some of the options that could be implemented to achieve the objective of salinity management.


Charting Neptune's Realm: From Classical Mythology To Satellite Imagery (Exhibit Guide), Osher Map Library And Smith Center For Cartographic Education Apr 2000

Charting Neptune's Realm: From Classical Mythology To Satellite Imagery (Exhibit Guide), Osher Map Library And Smith Center For Cartographic Education

Osher Map Library Miscellaneous Publications

Charting Neptune's Realm: From Classical Mythology to Satellite Imagery. April 4, 2000 to January 11, 2001

The charts in this exhibition explore how mariners have distinguished one piece of water from any other, by determining what phenomena can be delineated across the vast, trackless ocean and by developing notations to express those phenomena.


An Introduction To The Drought Monitor, Mark Svoboda Apr 2000

An Introduction To The Drought Monitor, Mark Svoboda

Drought Network News (1994–2001)

The idea of better monitoring and assessing drought has been a quest of NDMC director Don Wilhite for more than two decades. He has been an advocate of better climate monitoring, particularly drought monitoring, because drought is a normal, recurring hazard in virtually all of the United States. The challenge is to recognize drought, a slow-onset or “creeping” natural disaster, before a region is in the middle of one.

The most recent surge in interest in drought arose during the 1995–96 drought in the Southwest and southern Great Plains states. At the NDMC we discussed how we could do a …


From The Director: Spring 2000, Donald A. Wilhite Apr 2000

From The Director: Spring 2000, Donald A. Wilhite

Drought Network News (1994–2001)

I hope that those of our readers with Internet access will consider receiving future issues of Drought Network News online. We realize that some of you do not have access to the Internet, so we will continue to publish hard copies of the newsletter. If you are willing to receive the newsletter electronically, please contact Kim Klemsz as soon as possible. Our plan is to notify readers via email when each new issue of Drought Network News is available. Back issues of the newsletter are also available online.

This is a joint winter/spring issue of Drought Network News. It …


Influence Of Advection On Measurements Of The Net Ecosystem-Atmosphere Exchange Of Co2 From A Very Tall Tower, Chuixiang Yi, Kenneth J. Davis, Peter S. Bakwin, Bernard W. Berger, Linsey C. Marr Apr 2000

Influence Of Advection On Measurements Of The Net Ecosystem-Atmosphere Exchange Of Co2 From A Very Tall Tower, Chuixiang Yi, Kenneth J. Davis, Peter S. Bakwin, Bernard W. Berger, Linsey C. Marr

Publications and Research

In most studies of the net ecosystem-atmosphere exchange of CO2 (NEE) using tower-based eddy covariance( EC) systems it has been assumed that advection is negligible. In this study we use a scalar conservation budget method to estimate the contribution of advection to NEE measurements from a very tall tower in northern Wisconsin. We examine data for June-August 1997. Measured NEEo, calculated as the sum of the EC flux plus the rate of change of storage below the EC measurement level, is expected to be constant with measurement height, and we take the differences between levels as a measure of …


Spring 2000, Nsu Oceanographic Center Apr 2000

Spring 2000, Nsu Oceanographic Center

Currents

No abstract provided.


Circulation, Vol. 7, No. 2, Center For Coastal Physical Oceanography, Old Dominion University, Bettina Fach Apr 2000

Circulation, Vol. 7, No. 2, Center For Coastal Physical Oceanography, Old Dominion University, Bettina Fach

CCPO Circulation

Spring 2000 issue of CCPO Circulation featuring article "Cruising the Southern Ocean" by Bettina Fach


Wavelength Modulation Spectroscopy Of Water Vapor And Line Center Stabilization At 1.462 Μm For Lidar Applications, Colleen Marie Fitzgerald Apr 2000

Wavelength Modulation Spectroscopy Of Water Vapor And Line Center Stabilization At 1.462 Μm For Lidar Applications, Colleen Marie Fitzgerald

Electrical & Computer Engineering Theses & Dissertations

Wavelength modulation spectroscopy was employed to investigate water vapor absorption lines in the 1.462 µm wavelength region using an external-cavity diode laser. These measurements were necessary in the development of a lidar (light detection and ranging) instrument for differential absorption measurement of the concentration and movement of water vapor in the Earth's atmosphere. Differential absorption measurements require that the laser frequency remain stable throughout the duration of the measurement. To ensure this stability, the laser output wavelength is monitored and a feedback control loop set up to minimize laser line drift. Three lines were investigated in the 1.462 µm region. …


A Longitudinal Assessment Of Temperament In Octopus Bimaculoides, David Loyd Sinn Apr 2000

A Longitudinal Assessment Of Temperament In Octopus Bimaculoides, David Loyd Sinn

Dissertations and Theses

Cephalopods, including Octopus spp., are highly intelligent molluscs that play major roles in many marine food webs, both as top-level feeders (Ambrose, 1984) as well as by constituting a major source of protein for the animals above them (Lang, Hochberg, Ambrose, & Engle, 1997). They also are fascinating organisms for behavioral studies, with elaborate repertoires of behavior based on plasticity and learning (Wells, 1962a; 1962b; 1978) which in complexity rivals that of the vertebrates. The study of individual differences in behavior is a facet of behavioral research that has recently gained attention in the literature (Gosling & John, 1999). Traditionally, …


Tropospheric Reactive Odd Nitrogen Over The South Pacific In Austral Springtime, Jack E. Dibb, R. Talbot, Eric Scheuer, J D. Bradshaw, S T. Sandholm, D R. Blake, N J. Blake, Elliot Atlas, F Flocke Mar 2000

Tropospheric Reactive Odd Nitrogen Over The South Pacific In Austral Springtime, Jack E. Dibb, R. Talbot, Eric Scheuer, J D. Bradshaw, S T. Sandholm, D R. Blake, N J. Blake, Elliot Atlas, F Flocke

Earth Sciences

The distribution of reactive nitrogen species over the South Pacific during austral springtime appears to be dominated by biomass burning emissions and possibly lightning and stratospheric inputs. The absence of robust correlations of reactive nitrogen species with source-specific tracers (e.g., C2H2 [combustion], CH3Cl [biomass burning], C2Cl4 [industrial],210Pb [continental], and 7Be [stratospheric]) suggests significant aging and processing of the sampled air parcels due to losses by surface deposition, OH attack, and dilution processes. Classification of the air parcels based on CO enhancements indicates that the greatest influence was found in …


Validation Of The Ionospheric Forecast Model (Ifm) Version 3, Michael D. Scott Mar 2000

Validation Of The Ionospheric Forecast Model (Ifm) Version 3, Michael D. Scott

Theses and Dissertations

The purpose of this research was to validate the Ionospheric Forecast Model (IFM) Version 3 to assess its suitability and usefulness as an operational tool. The Ionospheric forecast model is a first principles computer model designed to forecast the state of the global ionosphere to 24 hours. The scope was limited to a comparison of the F2 layer critical frequency (foF2) and peak electron density (hmF2) against observed ionosonde data. The model was run with global solar and geomagnetic indices and Information from Digitial Ionospheric Sounding System (DISS) observations as inputs. The DISS observations were input through the Parameterized Real-Time …


Pesticide Ground Water Monitoring Project - Phase Vii, Terry Nichols Mar 2000

Pesticide Ground Water Monitoring Project - Phase Vii, Terry Nichols

Arkansas Water Resources Center Technical Reports

No abstract provided.


Chemical Nox Budget In The Upper Troposphere Over The Tropical South Pacific, Martin G. Schultz, Daniel J. Jacob, J D. Bradshaw, S T. Sandholm, Jack E. Dibb, R. Talbot, Hanwant B. Singh Mar 2000

Chemical Nox Budget In The Upper Troposphere Over The Tropical South Pacific, Martin G. Schultz, Daniel J. Jacob, J D. Bradshaw, S T. Sandholm, Jack E. Dibb, R. Talbot, Hanwant B. Singh

Earth Sciences

The chemical NOx budget in the upper troposphere over the tropical South Pacific is analyzed using aircraft measurements made at 6-12 km altitude in September 1996 during the Global Tropospheric Experiment (GTE) Pacific Exploratory Mission (PEM) Tropics A campaign. Chemical loss and production rates of NOx along the aircraft flight tracks are calculated with a photochemical model constrained by observations. Calculations using a standard chemical mechanism show a large missing source for NOx; chemical loss exceeds chemical production by a factor of 2.4 on average. Similar or greater NOx budget imbalances have been reported in analyses of data from previous …


Modeling The Growth Dynamics Of Antarctic Krill Euphausia Superba, Eileen E. Hofmann, Cathy M. Lascara Mar 2000

Modeling The Growth Dynamics Of Antarctic Krill Euphausia Superba, Eileen E. Hofmann, Cathy M. Lascara

CCPO Publications

A time-dependent, size-structured, bioenergetically based model was developed to examine the growth dynamics of Antarctic krill Euphausia superba 2 to 60 mm in size. The metabolic processes included in the model are ingestion, a baseline respiration, respiratory losses due to feeding and digestion, and an activity-based respiration factor. The total of these processes, net production, was used as the basis for determining the growth or shrinkage of individuals. Size-dependent parameterizations for the metabolic processes were constructed from field and laboratory measurements. Environmental effects were included through time series of pelagic phytoplankton concentration that were derived from data sets collected west …


An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll Mar 2000

An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll

Theses and Dissertations

Understanding lightning characteristics over land and water is vital to achieving optimal safety and success in Air Force missions. Lightning safety rules are often based on experience rather than a scientific understanding of lightning. Examining lightning characteristics over water and land will assist in a better understanding of lightning and provide answers that can protect human lives and property. Water and land have different compositions and surface conductivity values. A lightning stroke is detected through a change in the electro-magnetic field at the surface. The change in surface conductivity values from land to water can affect the detection of a …


Extensible Markup Language As A Weather Tool, Michael J. Calidonna Mar 2000

Extensible Markup Language As A Weather Tool, Michael J. Calidonna

Theses and Dissertations

This thesis is a proof of concept work that will extend the Core Mapping Application Program Interface (CMAPI) components to include weather data. The CMAPI project is headed by Air Force Research Lab (AFRL)/Information Directorate Information Handling Branch (IFEB) at Rome labs in Rome, New York. This work extends the CMAPI project in two distinct areas. The first goal is to figure out how to overlay and display weather data on a dynamically linked Internet platform. This was accomplished by incorporating existing data from the Air Force Weather Agency (AFWA) into the CMAPI program in a static environment. The other …


A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys Mar 2000

A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys

Theses and Dissertations

This thesis demonstrates the potential for using time-delay neural networks to provide Launch Weather Officers (LWOs) at 45th Weather Squadron (45 WS) with advance warning of wintertime (November-March) peak wind speeds at the Atlas launch pad. The 45 WS provides weather support to the United States space program at Cape Canaveral Air Station, NASA's Kennedy Space Center, and Patrick Air Force Base. Due to the complex wintertime environment produced by the effects of friction and instability, 45 WS LWOs consider wintertime launch pad winds their toughest forecast challenge. Neural networks were developed, trained, and tested using observations of wintertime peak …


Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman Mar 2000

Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman

Theses and Dissertations

This thesis uses statistical analysis to forecast the probability of meeting or exceeding the maximum allowable wind speeds for each of the launch pads at the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). Wind data were collected from the Weather Information Network Display System (WINDS), a collection of 47 meteorological towers located throughout KSC and CCAS, over a period of five winters. A Fortran program was written to calculate conditional probabilities of meeting or exceeding a given threshold speed during eight consecutive one-hour periods, using the current wind direction and peak wind speed as inputs. Forecast probabilities …


A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin Mar 2000

A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin

Theses and Dissertations

Lightning detection is an essential part of safety and resource protection at Cape Canaveral. In order to meet the unique needs of launching space vehicles in the thunderstorm prone Florida environment, Cape Canaveral has the only operational three- dimensional (3D) lightning detection network in the world, the Lightning Detection and Ranging (LDAR) system. Although lightning activity is detected in three dimensions, the current LDAR display, developed 20 years ago, is two-dimensional. This thesis uses modern three-dimensional graphics, object-oriented software design, and innovative visualization techniques to develop a 3D visualization application for LDAR data.


An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson Mar 2000

An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson

Theses and Dissertations

A wet-microburst event on 16 August 1994 at the Kennedy Space Center's Shuttle Landing Facility alerted forecasters from the 45th Weather Squadron (45WS), the provider of weather support to the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS), to the challenges of wet-microburst prediction. Although there was no operational impact, this event caused the 45WS to revise their severe thunderstorm forecasting procedures to specifically address microbursts, resulting in the locally developed Microburst-Day Potential Index (MDPI). MDPI provides a several-hour outlook of microburst potential based on the results of the Microburst and Severe Thunderstorm (MIST) project. The 45WS also …


Quantifying The Protonospheric Effect On Prism, Kelly B. Doser Mar 2000

Quantifying The Protonospheric Effect On Prism, Kelly B. Doser

Theses and Dissertations

The total electron content (TEC) contribution to a Parameterized Real-time Ionospheric Specification Model (PRISM) calculation has been studied using protonospheric TEC measurements made by Global Positioning Satellites (GPS). Including the protonosphere proved challenging to both the calibration of GPS measurements and execution of PRISM. Though 46 days of GPS measurements were acquired, only 40 were successfully calibrated, and only 35 of those were used in the study. Data issues such as availability and completeness as well as measurement quality affected 6 of the days used. Calibration was done at Pittsburgh by excluding all measurements below 40.750 N. latitude cutoff. This …