Digital Commons Network^™

The Influence Of Wave– And Zonal Mean–Ozone Feedbacks On The Quasi-Biennial Oscillation, Eugene Cordero, Terrence R. Nathan

Faculty Publications, Meteorology and Climate Science

The effects of wave and zonal mean ozone heating on the evolution of the quasi-biennial oscillation (QBO) are examined using a two-dimensional mechanistic model of the equatorial stratosphere. The model atmosphere is governed by coupled equations for the zonal mean and (linear) wave fields of ozone, temperature, and wind, and is driven by specifying the amplitudes of a Kelvin wave and a Rossby–gravity wave at the lower boundary. Wave–mean flow interactions are accounted for in the model, but not wave–wave interactions.

A reference simulation (RS) of the QBO, in which ozone feedbacks are neglected, is carried out and the results …

Investigation Of Optimum Sample Number And Timing For Determining Pollution Loads, T. S. Soerens, Marc A. Nelson

Arkansas Water Resources Center Technical Reports

In order to determine the impacts of non point source (NPS) pollution and to develop Total Maximum Daily Loads (Tr\tfDLs), accurate measurements of pollution loads in streams are critical. The objectives of this study were to accurately detemline pollutant loads at two sites by intensive storm sampling, to develop sub-sampling and other data analysis techniques, to detemline the effect of sample interval on load calculation accuracy, and to find the minimum sample interval required to determine storm loads at a required accuracy. The two stream sites used were a 1st order and a 3rd order stream in the Illinois River …

Multiple Spatial Scale Assessment Of Coral Reef And Hard-Bottom Community Structure In The Florida Keys National Marine Sanctuary, Steven Miller, Dione W. Swanson, Mark Chiappone

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

The zoning plan for the Florida Keys National Marine Sanctuary (FKNMS) established 23 relatively small no-fishing zones distributed mostly along the offshore reef tract in 1997. In 1999, a two-stage, stratified random sampling design based on the proportion of coral reef and hard-bottom types within the FKNMS was conducted. Our study focused on differences in coverage, density, and condition of benthic organisms with respect to habitat type, regional variations, and differences between no-fishing zones and reference sites at 80 locations spanning 200 km. Most variables exhibited significant spatial differences by habitat type or between individual no-fishing zones and reference sites …

Announcements: Fall 2000

Drought Network News (1994–2001)

Contents:

2000 National Disaster Medical System Conference

Management Strategies to Mitigate Drought in the Mediterranean: Monitoring, Risk Analysis and Contingency Planning

Potential Use Of Noaa/Avhrr Satellite Data For Monitoring Environmental Change In Turkey, Ali Umran Komuscu

Drought Network News (1994–2001)

In Turkey, desertification has been taking place in areas of low rainfall and minimal vegetative cover. In particular, the central, eastern, and southeastern parts of the country are vulnerable to desertification because of erosion, deforestation, and degradation of vegetative cover. Rivers of those regions are characterized by very high sediment yields. Nearly 60% of the country’s soils are subjected to severe erosion and approximately 450 million tons of sediment are carried to rivers each year. Meanwhile, wind erosion has been a very effective desertification process in central and southeastern parts of the country, where annual rainfall varies around 400–500 mm/year. …

Workshop On Drought-Related Issues In Fars Province, Iran: Critical Points And Resolutions, M. J. Nazemosadat, S. Amin, A. A. Kamgare-Haghighi, D. Khalili

Drought Network News (1994–2001)

As a result of the occurrence of overwhelming severe drought over most parts of the Islamic Republic of Iran, an educational/professional workshop on drought issues was held at the College of Agriculture, Shiraz University in Iran, October 18–19, 2000. The workshop was sponsored by the College of Agriculture, the office of Fars Provincial Government, the Agricultural Bank, and Shiraz Abfa Company. The workshop was mainly focused on the assessment of drought impacts and severity in Fars province, in the southern part of Iran.

The inauguration ceremony was attended by some of the parliament members (from Fars province), the Chancellor of …

From The Director: Fall 2000, Donald A. Wilhite

Drought Network News (1994–2001)

The NDMC hosted the first annual “Drought Monitor Forum” in November. Most of the readers of Drought Network News are probably aware of the Drought Monitor web site (http://enso.unl.edu/ monitor/index.html) and the products that are provided to users. (Mark Svoboda of the NDMC provided an overview of the Drought Monitor product in the Winter/Spring 2000 issue of Drought Network News.) This weekly product, jointly produced by the NDMC, U.S. Department of Agriculture, and NOAA’s Climate Prediction Center, has been widely accepted in the United States, and other countries are considering the adoption of a similar technique for mapping drought …

Improving Drought Early Warning Systems In The Context Of Drought Preparedness And Mitigation, Donald A. Wilhite, M. V. K. Sivakumar, Deborah Wood

Drought Network News (1994–2001)

Effective drought early warning systems are an integral part of efforts worldwide to improve drought preparedness. Timely and reliable data and information must be the cornerstone of effective drought policies and plans. In pursuit of the goal of improving the effectiveness of drought early warning systems, participants of the experts meeting were asked to address three fundamental questions:

1. What is your assessment of the current status of drought early warning systems?
2. What are the shortcomings, limitations, and needs for drought early warning systems?
3. How can drought early warning systems be improved to better support drought preparedness and …

Using The Spi To Monitor The 1999-2000 Drought In Northeastern Argentina, Roberto Zanvettor, Andres Ravelo

Drought Network News (1994–2001)

Drought risk is a major concern across many regions of Argentina because precipitation is extremely variable. One of these regions, the Pampas, is the main agricultural and livestock production area, extending over 60 million hectares. This region was recently surveyed to detect, monitor, and assess the occurrence of drought using a network of 27 meteorological stations and the Standardized Precipitation Index (SPI), developed by McKee et al. (1993). The SPI has various categories that define drought intensities. A period is considered humid when the SPI value is greater than +1 and a period is considered dry when the value of …

Fall 2000, Nsu Oceanographic Center

Currents

No abstract provided.

Experimental Goes Sounder Products For The Assessment Of Downburst Potential, Gary P. Ellrod, James P. Nelson Iii, Michael R. Witiw, Lynda Bottos, William P. Roeder

Aeronautics Faculty Publications

Several experimental products derived from Geostationary Operational Environmental Satellite (GOES) Sounder retrievals (vertical profiles of temperature and moisture) have been developed to assist weather forecasters in assessing the potential for convective downbursts. The product suite currently includes the wind index (WINDEX), a dry microburst index, and the maximum difference in equivalent potential temperature (θe) from the surface to 300 hPa. The products are displayed as color-coded boxes or numerical values, superimposed on GOES visible, infrared, or water vapor imagery, and are available hourly, day and night, via the Internet. After two full summers of evaluation, the products have been shown …

Copper Complexation And Speciation In The Western South And Equatorial Atlantic Ocean, John A. Consolvo

Chemistry & Biochemistry Theses & Dissertations

Presented here are the first data on copper complexation and speciation in the South Atlantic Ocean. Samples were collected at six vertical profile stations and along the surface (1m) transect during the 1996 IOC Baseline Contaminant Survey. Copper complexation measurements were made for the surface transect (1m) samples and three of the six vertical profile stations (1m - ~500m) using differential pulse anodic stripping voltammetry (DPASV) with a thin mercury film, rotating glassy carbon disk electrode (TMFRGCDE).

A strong organic copper complexing ligand (L₁; log K' _cuL1/cu2+ > 11. 8 ± 0 .4) was detected in 57% of all …

Circulation, Vol. 7, No. 3, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 2000 issue of CCPO Circulation featuring article "Worldwide Coastal Ocean Research at CCPO"

Response Of A First-Order Stream In Maine To Short-Term In-Stream Acidification, S. A. Norton, R. Wagai, T. Navratil, J. M. Kaste, F. A. Rissberger

Dartmouth Scholarship

An experimental short-term acidification with HCl at a first-order stream in central Maine, USA was used to study processes controlling the changes in stream chemistry and to assess the ability of stream substrate to buffer pH. The streambed exerted a strong buffering capacity against pH change by ion exchange during the 6-hour acidification. Streambed substrates had substantial cation and anion exchange capacity in the pH range of 4.1 to 6.5. The ion exchange for cations and SO₄^2- were rapid and reversible. The speed of release of cations from stream substrates was Na¹⁺> Ca²⁺ > Mg²⁺ > Al …

Resolving Ambiguities In Gravity Wave Propagation Directions Inherent In Satellite Observations: A Simulation Study, Michael P. Hickey Ph.D., Jason S. Brown

Publications

We simulate space-based, sub-limb viewing observations of airglow brightness fluctuations caused by atmospheric gravity wave interactions with the O2 atmospheric airglow, and we demonstrate that, due to the geometry associated with such observations, the brightness fluctuations observed for the optically thick 0–0 band emission will always appear stronger for waves traveling towards the observer (satellite). The effect should be most noticeable for waves having relatively small vertical wavelengths (∼10 km) and horizontal wavelengths of 50 km or greater. For waves of short (∼100 km) horizontal wavelength, the brightness fluctuation anisotropy with respect to viewing direction may also be evident in …

Spatial And Temporal Changes In Land Use And Land Cover From 1988 To 1992 In The Upper White River Watershed, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Changes in Land Use and Land Cover (LULC) in the upper White River Watershed from 1988 to 1992 were analyzed and plotted using the geographic information system known as Geographic Resources Analyses Support System (GRASS). This portion of the White River Watershed includes two sub-basins the East Fork and the Middle Fork. In addition, LULC changes were determined for two smaller sub-basins, Shumate Creek and Cannon Creek, located in the East Fork of the White River. The sources and methods of interpretation of the 1988 and 1992 of data were different. Thus, there were variations in how certain portions of …

Ground Water In Northwest Arkansas: Minimizing Nutrient Contamination From Non-Point Sources In Karst Terrane, R. K. Davis, J. V. Brahana, J. S. Johnston

Arkansas Water Resources Center Technical Reports

The purpose of the project is to evaluate the effectiveness of Best Management Practices (BPMs) in preventing non-point source contamination of the ground-water resources in the karst terrane of northwestern Arkansas. Limestone and dolomite aquifers in the region are highly vulnerable to contamination. Ground-water studies performed in the region during the last two decades indicate degradation of these carbonate aquifers by nutrients and bacteria. The expeditious growth of the poultry industry during this period, in combination with the inordinate population growth of the region constitute a threat to the ground-water resources from both point sources and non-point sources of contamination. …

Illinois River 1999 Pollutant Loads At Arkansas Higway 59 Bridge, Marc A. Nelson, Thomas S. Soerens

Arkansas Water Resources Center Technical Reports

Automatic water samplers and aU. S. Geological Survey gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling for January 1, 1999 to December 31, 1999.

Interactive 3-D Visualization: A Tool For Seafloor Navigation, Exploration, And Engineering, Larry A. Mayer, Mark Paton, Lindsay Gee, James V. Gardner, Colin Ware

Center for Coastal and Ocean Mapping

Recent years have seen remarkable advances in sonar technology, positioning capabilities, and computer processing power that have revolutionized the way we image the seafloor. The massive amounts of data produced by these systems present many challenges but also offer tremendous opportunities in terms of visualization and analysis. We have developed a suite of interactive 3-D visualization and exploration tools specifically designed to facilitate the interpretation and analysis of very large (10's to 100's of megabytes), complex, multi-component spatial data sets. If properly georeferenced and treated, these complex data sets can be presented in a natural and intuitive manner that allows …

Economics Of Using On-Farm Reservoirs To Distribute Diverted Surface Water To Depleted Ground Water Areas Of The Southern Mississippi Valley Region, Eric J. Wailes, Kenneth B. Young, James Smartt, Gail L. Cramer

Arkansas Water Resources Center Technical Reports

Rapid ground water depletion has become a significant problem for parts of the Southern Mississippi River Valley. In 1997, the Arkansas Soil and Water Conservation Commission (ASWCC) declared six counties in the Grand Prairie of Arkansas critical ground water areas. A proposed solution to the ground water depletion problem in this region is to divert surplus flows from the White River by a canal system to the farmer stakeholders. To make the system work, on-farm reservoirs will be needed to store and manage the diverted surface water for crop irrigation use during the growing season.

Release Of No(X) From Sunlight-Irradiated Midlatitude Snow, R E. Honrath, Matthew C. Peterson, M P. Dziobak, Jack E. Dibb, Matthew Arsenault, S A. Green

Earth Sciences

Photochemical production and release of gas-phase NO(x) (NO + NO2) from the natural snowpack at a remote site in northern Michigan were investigated during the Snow Nitrogen and Oxidants in Winter study in January 1999. Snow was collected in an open 34 L chamber, which was then sealed with a transparent Teflon cover and used as an outdoor flow and reaction chamber. Significant increases in NO(x) mixing ratio were observed in synthetic and ambient air pulled through the sunlit chamber. [NO(x)] enhancements were correlated to ultraviolet sunlight intensity, reaching ~300 pptv under partially overcast midday, mid-winter conditions. These findings are …

Theoretical Basis For The Ce-Qual-W2 River Basin Model, Scott A. Wells, Thomas M. Cole

Civil and Environmental Engineering Faculty Publications and Presentations

The primary objective of this research is to integrate a riverine model into the existing W2 code that would provide the capability for modeling entire watersheds. This task was accomplished by the following steps:

• Formal derivation of governing equations and solution algorithm with general channel slope

• Detailed analysis of algorithm for linking branches and smooth implementation of boundary conditions between branches

• Algorithm development and changes to basic model code (including branch definitions with slope, slope correction to solution algorithm, transfer of momentum between internal branches)

These tasks were performed with the following constraints and initiatives:

• Utilize …

Alteration Processes Of Alkenones And Related Lipids In Water Columns And Sediments, H. Rodger Harvey

OES Faculty Publications

Alkenones produced by the haptophyte algae are currently being used as indices of sea surface temperature in recent and past ocean environments, but limited information is available concerning the impact of biotic and abiotic processes on the integrity of these long chain lipids. This synthesis provides selected background information on major alteration processes that must be considered before such indices can be used with confidence. A number of processes in the water column and surface sediments have the potential to impact the structural integrity of alkenones and compromise their ability as temperature markers. Processes discussed include the alteration of alkenone …

Trajectory Mapping: A Tool For Validation Of Trace Gas Observations, Gary A. Morris, James F. Gleason, Jerald Ziemke, Mark R. Schoeberl

Physics and Astronomy Faculty Publications

We investigate the effectiveness of trajectory mapping(TM) as a data validation tool. TM combines a dynamical model of the atmosphere with trace gas observations to provide more statistically robust estimates of instrument performance over much broader geographic areas than traditional techniques are able to provide. We present four detailed case studies selected so that the traditional techniques are expected to work well. In each case the TM results are equivalent to or improve upon the measurement comparisons performed with traditional approaches. The TM results are statistically more robust than those achieved using traditional approaches since the TM comparisons occur over …

Effects Of Planetary Wave-Breaking On The Seasonal Variation Of Total Column Ozone, Terrence R. Nathan, Eugene C. Cordero, Long Li, Donald J. Wuebbles

Faculty Publications, Meteorology and Climate Science

The effects of planetary wave breaking on the seasonal variation of total column ozone are investigated using a zonally averaged chemical-radiative-transport model of the atmosphere. The planetary wave breaking effects of zonal wavenumbers k=1 and k=2 are significant in the middle latitude stratosphere during Northern Hemisphere (NH) winter, whereas only wave k=1 is important during Southern Hemisphere (SH) winter. The mixing and induced meridional circulation due to the planetary wave breaking increases the seasonal variation of total column ozone in NH (SH) middle latitudes by ∼20% (∼10%).

Conclusions And Recommendations From The Central And Eastern European Workshop On Drought Mitigation

Drought Network News (1994–2001)

The importance of prevention and planning in drought mitigation was the impetus for the Central and Eastern European Workshop on Drought Mitigation, held April 12–15, 2000, in Budapest-Felsoőgöd, Hungary. The workshop was organized and sponsored by several Hungarian agencies: the Ministry of Agriculture and Rural Development; Ministry for Environment; Ministry of Transport, Communication and Water Management; Research and Development Division of the Ministry of Education; and Hungarian Meteorological Service. The United Nations Convention to Combat Desertification (UNCCD), Food and Agriculture Organization (FAO), United Nations Environment Programme (UNEP), World Meteorological Organization (WMO), European Commission Joint Research Centre (EC JRC–ISPRA), European Regional …

India’S Arid Region And The Current Drought, Pratap Narain, K. D. Sharma, A. S. Rao, D. V. Singh, B. K. Mathur, Usha Rani Ahuja

Drought Network News (1994–2001)

We recently surveyed some of the drought-affected areas (Figure 1) in the Indian arid region in a publication entitled “Strategy to Combat Drought and Famine in the Indian Arid Zone.” This article is a summary of the report.

The present drought in the arid and semiarid regions of India is due to the cumulative effect of inadequate rainfall during 1997–99. Twelve states in India are in the grip of severe drought, with Rajasthan, Gujarat, Andhra Pradesh, and Madhya Pradesh (Table 1) being the most affected. The Indian arid zone encompasses 32 million ha and is highly prone to droughts and …

The Drought In Chile And La Niña, Juan Quintana

Drought Network News (1994–2001)

Precipitation is one of the climatic elements most affected by the presence of La Niña in Chile. An important precipitation deficit begins during La Niña events, from latitude 45°S to the north. This deficit prevails most of the year, with winter (April–September) being most vulnerable to these anomalies. The central region of Chile (30°S to 40°S) has negative anomalies, with precipitation values 35% to 100% below the climatologic annual average. These rain deficiencies in Chile are determined by the persistence of anomalies of anticyclonal circulation of middle and subtropical latititudes and an area of anomalies of cyclonic circulation in the …

Talking Imperative For Grieving Farmers, Others, Cheryl Alberts

Drought Network News (1994–2001)

Farmers who are losing their livelihoods to the drought shouldn’t be surprised to feel depressed or angry, and neither should people around them. After all, these farmers are suffering a very real loss and they are grieving.

Farmers who lose a crop in many ways will react as have people who have lost loved ones, said John DeFrain, family and community development specialist at the University of Nebraska here. That is, they go into shock, denial and anger, and not necessarily in that order.

The loss of a crop means a loss of time, expenses, identity and, in some cases, …

From The Director: Summer 2000, Donald A. Wilhite

Drought Network News (1994–2001)

We had a fairly good response to the call in the previous issue of Drought Network News for readers to receive future issues online. I would encourage more of you to consider this option, as it will save distribution costs and expedite receipt of the newsletter. If you are willing to receive the newsletter electronically, please contact Kim Klemsz ([email protected]). Our plan is to notify you via e-mail when each new issue of Drought Network News is available. Back issues of Drought Network News are also available online.

At this writing, I am making final preparations for the Expert Group …