Physical Sciences and Mathematics Commons^™

Determination Of The Seasonal Changes In Nitrate And Phosphate Concentration And Phytoplankton Composition Within Selected Fertilized Lakes, Richard L. Meyer

Technical Reports

No abstract provided.

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …

A Preliminary Mass Balance Model Of Primary Productivity And Dissolved Oxygen In The Mississippi River Plume/Inner Gulf Shelf Region, Victor J. Bierman Jr., Scott C. Hinz, William J. Wiseman Jr., Nancy N. Rabalais, R. Eugene Turner

Faculty Publications

A deterministic, mass balance model for phytoplankton, nutrients, and dissolved oxygen was applied to the Mississippi River Plume/Inner Gulf Shelf (MRP/IGS) region. The model was calibrated to a comprehensive set of field data collected during July 1990 at over 200 sampling stations in the northern Gulf of Mexico. The spatial domain of the model is represented by a three-dimensional, 21-segment water-column .grid extending from the Mississippi River Delta west to the Louisiana-Texas border, and from the shoreline seaward to the 30-60 m bathymetric contours. Diagnostic analyses and numerical experiments were conducted with the calibrated model to better understand the environmental …

Comparison Of Continuous Records Of Near-Bottom Dissolved Oxygen From The Hypoxia Zone Along The Louisiana Coast, Nancy N. Rabalais, William J. Wiseman, R. Eugene Turner

Faculty Publications

Oxygen depletion is a seasonally dominant feature of the lower water column on the highly-stratified, riverine-influenced continental shelf of Louisiana. The areal extent of hypoxia (bottom waters ≤2 mg l−1 dissolved oxygen) in mid-summer may encompass up to 9,500 km2, from the Mississippi River delta to the upper Texas coast, with the spatial configuration of the zone varying interannually. We placed two continuously recording oxygen meters (Endeco 1184) within 1 m of the seabed in 20-m water depth at two locations 77 km apart where we previously documented midsummer bottom water hypoxia. The oxygen meters recorded considerably different oxygen conditions …

Climatic Impact Of The A.D. 1783 Asama (Japan) Eruption Was Minimal: Evidence From The Gisp2 Ice Core, G. A. Zielinski, R. J. Fiacco, Paul Andrew Mayewski, L. D. Meeker, S. Whitlow, M. S. Twickler, M. S. Germani, K. Endo, M. Yasui

Earth Science Faculty Scholarship

Assessing the climatic impact of the A.D. 1783 eruption of Mt. Asama, Japan, is complicated by the concurrent eruption of Laki, Iceland. Estimates of the stratospheric loading of H₂SO₄ for the A.D. 1108 eruption of Asama derived from the SO₄²⁻ time series in the GISP2 Greenland ice core indicate a loading of about 10.4 Tg H₂SO₄ with a resulting stratospheric optical depth of 0.087. Assuming sulfur emissions from the 1783 eruption were only one‐third of the 1108 event yields a H₂SO₄ loading value of 3.5 Tg and a stratospheric …

Wave-Modified Mean Exothermic Heating In The Mesopause Region, Michael P. Hickey Ph.D., R. L. Walterscheid

Publications

We employ a model of wave-driven OH nightglow fluctuations to calculate the effects of gravity waves on the chemical exothermic heating due to reactions involving odd hydrogen and odd oxygen species in the mesopause region. Using a model based on time means and deviations from those means, it is demonstrated that gravity waves contribute to the time-average exothermic heating. The effect can be significant because the fractional fluctuations in minor species density can be substantially greater than the fractional fluctuation of the major gas density. Our calculations reveal that the waves mitigate the exothermic heating, demonstrating their potential importance in …

The Moore's Creek Monitoring Project, D. R. Edwards, T, C, Daniel, J. F. Murdoch, P. F. Vendrell, D. J. Nichols

Technical Reports

No abstract provided.

The U.S. Space Program: Pioneering The Future, Sally Ride

James R. Thompson Leadership Lectures

Sally Ride, director of the California Space Institute and a physics professor at the University of California - San Diego, is one of the most celebrated scientists of our time. A former NASA astronaut, Dr. Ride is perhaps the best known for her pioneering accomplishments as the first American woman in space.

Dr. Ride flew two missions aboard the space shuttle Challenger (1983 and 1984). During the 1983 mission, the crew performed the first satellite deployment and retrieval with the shuttle's robot arm. The 1984 mission demonstrated the potential for satellite refueling by astronauts. Excerpt from the attached program

How Synchronous Are Neogene Marine Plankton Events?, Cinzia Spencer-Cervato, Hans R. Thierstein, David B. Lazarus, Jean-Pierre Beckmann

Cinzia Cervato

An electronic supplement of this material may be obtained on adiskette or Anonymous FTP from KOSMOS.AGU.ORG. (LOGIN toAGU's FTP account using ANONYMOUS as the username andGUEST as the password. Go to the right directory by typing CDAPEND. Type LS to see what files are available. Type GET and thename of the file to get it. Finally, type EXIT to leave the system.)(Paper 94PA01456, How synchronous are Neogene marine planktonevents?, by C. Spencer-Cervato, H. R. Thierstein, D. B. Lazarus, andJ-P Beckmann). Diskette may be ordered from American GeophysicalUnion, 2000 Florida Avenue, N.W., Washington, DC 20009; $15.00.Payment must accompany order. We analyzed …

Drought Vulnerability Of Rainfed Crops In Semiarid Tropics In India: New Methods Of Determining Rainfall Variability, U. S. Victor, N. N. Srivastava, P. Vijay Kumar

Drought Network News (1994-2001)

In dryland areas of India, rainfall is the main source of water for raising crops. For these areas, the greatest problem is not water shortage per se, but rather the tremendous variability in rainfall from year to year and season to season. In planning for the coming season, we currently have little or no ability to predict the date of the onset of rains or their amount, distribution, or duration. However, uncertainty about rainfall is lessened when information is available concerning the possible variability and frequencies of historical occurrences of rainfall. This information can be obtained by coupling water use …

Rainfall Patterns For India’S Karnataka State Show Above-Normal Precipitation For 1994-98, M. B. Rajegowda, D. M. Gowda

Drought Network News (1994-2001)

The Karnataka state, confined roughly within 11.5° N and 18.5° N latitude and 74° E and 78.5° E longitude, is situated on a table land at the point where the western and eastern Ghat range enclose the Nilgiri hill complex. It is enclosed by chains of mountains to its west, east, and south. The state consists mainly of plateau, with a higher elevation of 600 to 900 m amsl in small portions of the extreme north and northwest Karnataka and the whole of the southern half, an elevation of 300 to 600 m amsl in the north, and an elevation …

Circulation, Fall 1994, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1994 issue of CCPO Circulation featuring article "Modeling Circulation and Larval Transport in the Chesapeake Bay"

Representing Nodes And Arcs In 3d Networks, Glenn Franck, Colin Ware

Center for Coastal and Ocean Mapping

This paper introduces six graphical principles for 30 network displays. These are justified with examples from GraphVisualizer3D, a system developed by the authors to investigate the problems of 30 visualization of information networks. GraphVisualizer3D enables the exploration of sulface color, surface texture, object shape, arc shape and labeling conventions.

Viewing A Graph In A Virtual Reality Display Is Three Times As Good As A 2d Diagram, Colin Ware, Glenn Franck

Center for Coastal and Ocean Mapping

An experiment is reported which tests whether network information is more effectively displayed in a three dimensional space than in a two dimensional space. The experimental task is to trace a path in a network and the experiment is carried out in 2D, in a 3D stereo view, in a 2D view with head coupled perspective, and in a 3D stereo view with head coupled perspective; this last condition creates a localized virtual reality display. The results show that the motion parallax obtained from the head coupling of perspective is more important than stereopsis in revealing structural information. Overall the …

Simulations Of The Effects Of Water Vapor, Cloud Liquid Water, And Ice On Amsu Moisture Channel Brightness Temperatures, Bradley M. Muller, Henry E. Fuelberg, Xuwu Xiang

Publications

Radiative transfer simulations are performed to determine how water vapor and nonprecipitating cloud liquid water and ice particles within typical midlatitude atmospheres affect brightness temperatures T-B's of moisture sounding channels used in the Advanced Microwave Sounding Unit (AMSU) and AMSU-like instruments. The purpose is to promote a general understanding of passive top-of-atmosphere T-B's for window frequencies at 23.8, 89.0, and 157.0 GHz, and water vapor frequencies at 176.31, 180.31, and 182.31 GHz by documenting specific examples. This is accomplished through detailed analyses of T-B's for idealized atmospheres, mostly representing temperate conditions over land. Cloud effects are considered in terms of …

Phosphorus Immobilization In Poultry Litter And Litter-Amended Soils With Aluminum, Calcium And Iron Amendments, D. M. Miller, P. A. Moore Jr., T. C. Daniels

Technical Reports

Arkansas produces approximately one billion broilers each year. Phosphorous (P) runoff from fields receiving poultry litter is believed to be one of the primary factors affecting water quality in Northwest Arkansas. Poultry litter contains approximately 20 g P kg-1, of which about 2 g P kg-1 is water soluble. Soils that have received repeated heavy applications of litter may have water soluble P contents of as high as 10 mg P Kg-1 soil. The objective of this study was to determine if soluble P levels could be reduced in poultry litter and litter-amended soils with Al,Ca, and/or Fe amendments. Poultry …

Temporal Alternation Between Light- And Nutrient-Limitation Of Phytoplankton Production In A Coastal Plain Estuary., Jonathan Pennock, Jonathan H. Sharp

School of Marine Science and Ocean Engineering

ABSTRACT: The potential for Light- and nutrient-limitation of phytoplankton production was examined in the Delaware Estuary, USA, by combining a hierarchy of expenmental approaches including smallscale bioassay experiments, ecosystem-level analysis of nutrient concentration and stoichiometric ratios, and light-limitation modeling. Light was found to be the predominate regulator of phytoplankton growth throughout the estuary during the winter period as a result of high turbidity and a wellmixed water column. However, during late spring, phosphorus (P) was found to limit growth. This observation was confirmed at each of the experimental levels, and was related to several factors, including elevated input ratios (230:l) …

Water Quality Conditions In The Tidal Rappahannock River: Longitudinal And Dome Surveys In 1993, Kyeong Park, Albert Y. Kuo

Reports

Previous field surveys and modeling studies (Kuo et al. 1991; Park et al. 1993) indicated the presence of three different water quality regimes in the tidal Rappahannock River (Fig. 1), a western shore tributary of Chesapeake Bay: : Region I - hypoxic conditions during summer in the bottom water between km 0-55 : Region II - high chlorophyll concentration between km 80-147 : Region III - waste water discharges from sewage treatment plants To study the differences among these 3 reaches of the river, two types of field surveys were conducted during the summer of 1993: 1) longitudinal surveys in …

Soluble Acidic Species In Air And Snow At Summit, Greenland, Jack E. Dibb, R. Talbot, M H. Bergin

Earth Sciences Scholarship

Simultaneous measurements of the concentrations of soluble acidic species in the gas, aerosol and snow phases at Summit, Greenland were made during summer 1993. Mean concentrations of gas phase HCOOH, CH₃COOH, and HNO₃ (49±28, 32±17 and 0.9±0.6 nmol m⁻³ STP, respectively) exceeded the concentrations of aerosol-associated HCOO⁻, CH₃COO⁻, and NO₃⁻by 1–3 orders of magnitude. On average, SO₂ concentrations (0.9±0.6 nmol m⁻³ STP) were approximately 1/3 those of aerosol SO₄⁼, but this ratio varied widely due largely to changes in the concentration of …

Ozone Heating And The Destabilization Of Traveling Waves During Summer, Terrence R. Nathan, Eugene Cordero, Long Li

Eugene C. Cordero

The effects of ozone heating on the linear stability of lower stratospheric traveling waves of the summertime, extratropical circulation are examined. Based on coupled equations for the quasigeostrophic potential vorticity and ozone volume mixing ratio, it is shown that the diabatic heating arising from ozone advection can offset the damping due to Newtonian cooling, leading to wave amplification and significant changes in the structure and zonally rectified fluxes of the wave fields in both the lower stratosphere and troposphere. The vertical profile of the zonal mean wind plays a crucial role in determining whether the ozone heating destabilizes eastward and/or …

Circulation, Summer 1994, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Summer 1994 issue of CCPO Circulation featuring article "Large Influences From Small Features: Submarine Canyons"

Ozone Heating And The Destabilization Of Traveling Waves During Summer, Terrence R. Nathan, Eugene Cordero, Long Li

Faculty Publications, Meteorology and Climate Science

The effects of ozone heating on the linear stability of lower stratospheric traveling waves of the summertime, extratropical circulation are examined. Based on coupled equations for the quasigeostrophic potential vorticity and ozone volume mixing ratio, it is shown that the diabatic heating arising from ozone advection can offset the damping due to Newtonian cooling, leading to wave amplification and significant changes in the structure and zonally rectified fluxes of the wave fields in both the lower stratosphere and troposphere. The vertical profile of the zonal mean wind plays a crucial role in determining whether the ozone heating destabilizes eastward and/or …

Benthic Community Responses To Hypoxic Conditions In The Lower Rappahannock River, Virginia, Mary Elaine Smith

Biological Sciences Theses & Dissertations

The effects of seasonal low dissolved oxygen conditions upon benthic macroinvertebrate communities were studied in the lower Rappahannock River, a tributary of the Chesapeake Bay. Benthic communities were sampled during March, June, August, and September 1993 at five equidistant depths (5, 10, 15, 20, and 25 m) extending upwards from the deepwater Virginia Benthic Biological Monitoring Station LE3.4 located in the deep basin just inside the mouth of the Rappahannock River. Infaunal species diversity, richness, biomass, and density were measured along with the vertical depth distribution of organisms within the sediment. Significant sediment differences were found between the shallowest, 5 …

Flow Kinematics And Dynamics Of The Gulf Stream From Composite Imagery, Caitlin Patrice Mullen

OES Theses and Dissertations

A unique set of contemporaneous satellite-tracked drifters and five-day composite satellite images of the North Atlantic is studied in order to infer the near-surface flow kinematics and dynamics of the Gulf Stream. Using fractal and spectral analyses, two kinematic models, and a potential vorticity model, detailed comparisons are made between these data sets.

Fractal and spectral analyses show that the data set is not fractal, there is no geographic variability, and there is not a strong fractal scaling link between the drifter trajectories and composite temperature fronts as had been postulated by several investigators. These results indicate considerably more work …

Estimation Of Stratospheric Input To The Arctic Troposphere: 7be And 10be In Aerosols At Alert, Canada, Jack E. Dibb, David Meeker, R C. Finkel, J Southon, Marc W. Caffee, Leonard A. Barrie

Earth Sciences Scholarship

Concentrations of 7Be and 210Pb in 2 years of weekly high-volume aerosol samples collected at Alert, Northwest Territories, Canada, showed pronounced seasonal variations. We observed a broad winter peak in 210Pb concentration and a spring peak in 7Be. These peaks were similar in magnitude and duration to previously reported results for a number of stations in the Arctic Basin. Beryllium 10 concentrations (determined only during the first year of this study) were well correlated with those of 7Be; the atom ratio 10Be/7Be was nearly constant at 2.2 throughout the year. This relatively high value of 10Be/7Be indicates that the stratosphere …

Drought Profile: Haryana State In North India, K. Kailasa Nathan

Drought Network News (1994-2001)

Haryana state is considered the breadbasket of India, along with the Punjab state. The effects of drought (and mitigation of those effects) are therefore of considerable importance for the state. This article considers the state’s drought “profile” through a study of six drought years in Haryana.

Haryana has a semiarid climate in the southwest and a Gangetic plain environment in the rest of the state. About 50% of the state has a moisture deficit. One of the reasons for adverse crop production in the state during June–September is the early withdrawal or late onset of monsoon rains, which contribute nearly …

Drought And Southern Africa: A Note From The Harare Regional Drought Monitoring Centre, Leonard S. Uganai

Drought Network News (1994-2001)

Drought is a normal part of southern Africa’s climate and one of the most important natural disasters in southern Africa. In fact, it is becoming increasingly unusual for drought not to occur somewhere in southern Africa each year. The dependence of most southern African economies on rainfed agriculture emphasizes the importance of drought early warning products for short- and long-term decision making in various sectors of the national economies of the region. Following the 1991–92 drought, which ravaged more than 80% of southern Africa, many in southern Africa now realize the value of meteorological information in weather-sensitive decisions. Requests for …

Drought In Beijing, 1992-93, Zhuang Xie, Dagang Chen

Drought Network News (1994-2001)

Beijing, located in northeast China, has a semiarid monsoon climate, with summer rainfall providing about 70% of the annual precipitation. This climate is conducive to crop growth, although insufficient summer rainfall in 1992–93 caused reductions in crop yields. Normalized departures of monthly precipitation (DR/R%) are shown in Figure 1. Although some months show above-normal precipitation (for example, November 1992, with a rainfall amount [43.3 mm] 7.5 times the normal), rainfall for the 1993 growing period was marked by negative departures from normal. Of the months of the 1993 growing season, only July recorded above-normal rainfall. Precipitation departures in May, September, …

Droughts Over Homogeneous Regions Of India: 1871–-1990, B. Parathasarathy, A. A. Munot, D. R. Kothawale

Drought Network News (1994-2001)

The summer monsoon (June through September), or southwest seasonal rains, contribute 78% of India’s annual rainfall. It is the greatest climatic water resource of India. The country’s agriculture and food production depend on these rains. Rainfed farming areas in India account for about 70% of the total arable land in the country, with nearly 100 million ha depending on the monsoon rains. The rains also contribute to power generation and industrial production.