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1996

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Articles 1 - 30 of 156

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Watershed Prioritization, David G. Parker, Rod Williams, Hubert D. Scott Dec 1996

Watershed Prioritization, David G. Parker, Rod Williams, Hubert D. Scott

Technical Reports

The overall objective of this two-year study was to evaluate the water quality in the thirty-seven sub-basin watersheds in the Illinois River in Arkansas and to arrive at a watershed prioritization list to use in targeting non-point source activities. A water quality monitoring program was conducted with sampling in all thirty-seven sub-basins during both storm and base flow events and more intensive sampling in eight representative sub-basins during stOffil events. Each sub-basin was sampled seasonally during low flow (base-flow) conditions and during high flow storm (storm flow) conditions. In addition to the regular sampling, the intensive sub-basins were sampled approximately …


Wdrażanie Monitoringu Zanieczyszczeń Powietrza Atmosferycznego W Kielcach, Marian Mazur, Robert Oleniacz, Marek Bogacki Dec 1996

Wdrażanie Monitoringu Zanieczyszczeń Powietrza Atmosferycznego W Kielcach, Marian Mazur, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

Assumptions for regional environmental monitoring in the province of Kielce were developed as early as 1992. Since the beginning of particular attention were monitoring the air. The article presents the next step in the implementation of this monitoring, associated with verification of the location and the measuring range of points to measure the concentrations of air pollutants in Kielce. As a result of analysis and calculations, it was found that the original location is not always correct and does not reflect the spatial differentiation of pollutant concentrations. The proposed changes in the position of monitoring points or measurement methods were …


Zastosowanie Metody Obliczeniowo-Pomiarowej Do Oceny Stanu Zanieczyszczenia Powietrza W Nowym Sączu, Marian Mazur, Marek Bogacki, Robert Oleniacz Dec 1996

Zastosowanie Metody Obliczeniowo-Pomiarowej Do Oceny Stanu Zanieczyszczenia Powietrza W Nowym Sączu, Marian Mazur, Marek Bogacki, Robert Oleniacz

Robert Oleniacz

Assessment of the state of air pollution in the urban area is a difficult and complex task. Depending on the method of assessment the procedure requires a comprehensive research and calculations of air emissions from all sources occurring in the area and the use of atmospheric dispersion models or large-scale implementation of direct measurements of air pollutant concentrations. Both of these methods may also be applied simultaneously to their mutual verification.

The article presents the results of such a comprehensive assessment of air pollution on the example of the city of Nowy Sacz (Poland). This involved determining the emissions of …


Function Of Funnel-Shaped Coral Growth In A High-Sedimentation Environment, Bernhard Riegl, Carlton Heine, George M. Branch Dec 1996

Function Of Funnel-Shaped Coral Growth In A High-Sedimentation Environment, Bernhard Riegl, Carlton Heine, George M. Branch

Marine & Environmental Sciences Faculty Articles

Advantages and disadvantages of a funnel-shaped growth in 2 coral species (Acropora clathrata, Turbinaria peltata) in a high-sedimentation environment (Natal, South Africa) were observed in the field and modeled in a flow tank. Funnel-shaped growth serves different purposes in different hydrographic settings. In calm waters with little currents (in our case deep reef areas, 18 to 25 m) funnel-shaped colonies served as 'sacrificial sediment traps': all sediment trapped inside the funnel was directed towards the centre, where it was concentrated. There, tissues underwent necroses, but all other tissues remained sediment free and healthy. In areas with high currents (in our …


Analysis Of Multimode Low-Probability-Of-Intercept (Lpi) Communications With Atmospheric Effects, Ala Ghordlo Dec 1996

Analysis Of Multimode Low-Probability-Of-Intercept (Lpi) Communications With Atmospheric Effects, Ala Ghordlo

Theses and Dissertations

This research expanded Low Probability of Intercept (LPI) communications analysis in two areas. First, multimode communication was included to account for ground to ground and air to ground links in addition to the standard air to air links traditionally used in LPI analysis. The propagation equations for the three modes of interest were derived and included in LPI analytic models in the form of a mode quality factor to account for multimode LPI scenarios. This new quality factor was used in studying several communication and interception link combinations. Variations due to differences between the communication and interception modes were presented …


Performance Analysis Of A Hartman Wavefront Sensor Used For Sensing Atmospheric Turbulence Statistics, Toby D. Reeves Dec 1996

Performance Analysis Of A Hartman Wavefront Sensor Used For Sensing Atmospheric Turbulence Statistics, Toby D. Reeves

Theses and Dissertations

Atmospheric turbulence parameters, such as Fried's coherence diameter, the outer scale of turbulence, and the turbulence power law, are related to the wavefront slope structure function (SSF). The SSF is defined as the second moment of the wavefront slope difference as a function of both time and position. Knowledge of the SSF allows turbulence parameters to be estimated. Hartmann wavefront sensor (H-WFS) slope measurements composed of both signal and noise, allow the SSF to be estimated by computing a mean square difference of H-WFS slope measurements. The quality of the SSF estimate is quantified by the signal-to-noise ratio (SNR) of …


Deconvolution From Wavefront Sensing Using Optimal Wavefront Estimators, Scott R. Maethner Dec 1996

Deconvolution From Wavefront Sensing Using Optimal Wavefront Estimators, Scott R. Maethner

Theses and Dissertations

A cost effective method to improve the space surveillance mission performance of United States Air Force (USAF) ground-based telescopes is investigated and improved. A minimum variance wavefront estimation technique is used to improve Deconvolution from Wavefront Sensing (DWFS), a method to mitigate the effects of atmospheric turbulence on imaging systems that does not require expensive adaptive optics. Both least-squares and minimum variance wavefront phase estimation techniques are investigated, using both Gaussian and Zernike polynomial elementary functions. Imaging simulations and established performance metrics are used to evaluate these wavefront estimation techniques for a one-meter optical telescope. Performance metrics include the average …


Investigation Of Ba, Bao, Sr And Sro Pulsed Laser-Induced Vapor Plumes In N2, O2, Microwave Discharged O2, And Vacuum At Low Laser Fluence, David L. Byers Dec 1996

Investigation Of Ba, Bao, Sr And Sro Pulsed Laser-Induced Vapor Plumes In N2, O2, Microwave Discharged O2, And Vacuum At Low Laser Fluence, David L. Byers

Theses and Dissertations

Ba, BaO, Sr and SrO were ablated by 248 nm laser pulses at fluences ranging from 270 mJ-/sq cm to 575 mJ-/sq cm in vacuum and in 25 mtorr atmospheres of N2, O2 and microwave-discharged O2. The spectral emissions of these plumes were compared for indications of ionization due to Ba or Sr collisions with each gas. The addition of a background gas increased the ion and neutral signature across the spectrum. SrO band emission was observed at 16,600-16,900/cm and possible BaO band emissions were observed in the 18,250-18,400/cm, 19,000-19700/cm and 19,800-20,000/cm regions. A screened plate ion probe was use …


Mp731: New England Killing Frost Records By Zone, William R. Baron, David C. Smith Nov 1996

Mp731: New England Killing Frost Records By Zone, William R. Baron, David C. Smith

Miscellaneous Publications

This publication provides a deeper look at the killing frost data that is analyzed and summarized in Maine Agricultural and Forest Experiment Station Bulletin 846. The presentation in Bulletin 846 is designed to help planners and analysts. Individual readers, historians, botanists, agronomists, ecologists, and others may find a deeper look at the materials useful. Miscellaneous Publication 731 provides those data by climate zone on a yearly basis.


B846: Growing Season Parameter Reconstructions For New England Using Killing Frost Records, 1697-1947, William R. Baron, David C. Smith Nov 1996

B846: Growing Season Parameter Reconstructions For New England Using Killing Frost Records, 1697-1947, William R. Baron, David C. Smith

Bulletins

In New England, killing frosts in the late spring and early fall mark the limits of the region's growing seasons. Over the years, farmers have tried to anticipate when to plant and when to harvest to safely prevent their crops from experiencing the harmful effects of freezing. As a hedge against failing memory, some farmers kept notes on when killing frosts occurred so that they could more readily calculate in the years to come when to sow and when to reap. Some of these notes have survived and are now preserved in archives and libraries across the region, or remain …


Out Of Focus, John C. Dernbach Nov 1996

Out Of Focus, John C. Dernbach

John C. Dernbach

No abstract provided.


Observation Of Spatial Variability Of Diurnal Thermocline And Rain-Formed Halocline In The Western Pacific Warm Pool, Alexander Soloviev, Roger Lukas Nov 1996

Observation Of Spatial Variability Of Diurnal Thermocline And Rain-Formed Halocline In The Western Pacific Warm Pool, Alexander Soloviev, Roger Lukas

Marine & Environmental Sciences Faculty Articles

High-resolution measurements of temperature and salinity were made in the near-surface layer of the ocean during the Tropical Oceans-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment, using probes mounted on the bow of the R/V Moana Wave. Because of surface waves and pitching of the vessel, the bow probes profiled the near-surface layer of the ocean within depths of 0–4.0 m. In the near-surface layer of the ocean in the western Pacific warm pool, strong variability of temperature and salinity produced by diurnal heating and/or rain was often observed. The contoured density field revealed cases of pronounced spatial variability. The shallow …


Species Composition, Abundance, And Vertical Distribution Of The Stomiid (Pisces: Stomiiformes) Fish Assemblage Of The Gulf Of Mexico, Tracey Sutton, T. L. Hopkins Nov 1996

Species Composition, Abundance, And Vertical Distribution Of The Stomiid (Pisces: Stomiiformes) Fish Assemblage Of The Gulf Of Mexico, Tracey Sutton, T. L. Hopkins

Marine & Environmental Sciences Faculty Articles

Species composition, abundance, and vertical distribution of the stomiid fish assemblage were investigated in the eastern Gulf of Mexico, a low-latitude, oligotrophic oceanic ecosystem. Seventy-two described species, representing 18 genera, and one undescribed species were identified from 1155 trawl samples. With an additional 10 species reported elsewhere, the stomiid species number now known equals 83, making the Stomiidae the most diverse fish family in the Gulf of Mexico. The assemblage was dominated by three species,Photostomias guernei, Chauliodus sloani and Stomias affinis. These species, as well as four other common species, exhibited an asynchronous diel vertical migration pattern (450–900 …


Public Beach Assessment Report Gloucester Point Public Beach, Gloucester County, Virginia, Donna A. Milligan, C. Scott Hardaway Jr., George R. Thomas Nov 1996

Public Beach Assessment Report Gloucester Point Public Beach, Gloucester County, Virginia, Donna A. Milligan, C. Scott Hardaway Jr., George R. Thomas

Reports

Gloucester Point Public Beach is located at the southern end of Gloucester County, Virginia on the York River. It is a southeastward facing shoreline about 960 ft long and it is part of a larger stretch of moderately low shore between Sarah Creek and the George P. Coleman Bridge. While no shoreline improvement projects have taken place at the public beach, shore protection projects updrift and including the Virginia Institute of Marine Science (VIMS) affect it. In 1983, erosion along the shoreline at VIMS just updrift of the public beach led to the installation of a riprap revetment in front …


Directory Of Water Related Courses Offered At Colleges And Universites In Arkansas, Kenneth F. Steele Nov 1996

Directory Of Water Related Courses Offered At Colleges And Universites In Arkansas, Kenneth F. Steele

Technical Reports

This publication lists the water and water-related courses at several universities and colleges in Arkansas as reported during the Fall of 1996. It Is anticipated that users of this directory will extend beyond college students, and will include professionals seeking continuing education, and professors desiring to exchange information on courses. This directory is not an "absolute" source of water and water-related courses because all of the higher learning institutions in Arkansas are not listed, and, secondly, because the definition of "water and water-related" varies from institution to institution. None-the-less this directory provides a very valuable and impressive reference on water …


Historical Biomass Burning: Late 19th Century Pioneer Agriculture Revolution In Northern Hemisphere Ice Core Data And Its Atmospheric Interpretation, G. Holdsworth, K. Hiuchi, G. A. Zielinski, Paul Andrew Mayewski, M. Wahlen, B. Deck, P. Chylek, B. Johnson, P. Damiano Oct 1996

Historical Biomass Burning: Late 19th Century Pioneer Agriculture Revolution In Northern Hemisphere Ice Core Data And Its Atmospheric Interpretation, G. Holdsworth, K. Hiuchi, G. A. Zielinski, Paul Andrew Mayewski, M. Wahlen, B. Deck, P. Chylek, B. Johnson, P. Damiano

Earth Science Faculty Scholarship

Ice core data from Yukon and Greenland spanning from ∼1750 to 1950 indicate that between ∼1850 and ≤1910 a clear atmospheric signal exists of an episodic biomass burning event that is referred to as the Pioneer Agriculture Revolution. This is best seen in NH4+ ion and particulate concentrations but also in some limited black carbon concentration data, where for all three quantities maximum levels reach about 3 times the prerevolution background concentrations. Tree cellulose δ13C data and some early, controversial, French, air CO2 data, occurring within the same time interval, are interpreted as providing other …


Food Security In The Southern African Development Community States, Joshua Chigodora Oct 1996

Food Security In The Southern African Development Community States, Joshua Chigodora

Drought Network News (1994-2001)

The 1995–96 cereal harvest in the Southern African Development Community (SADC) is the best within the last ten years. Provisional assessments project a regional maize surplus of 2.08 million tons, a 72% increase in production over the previous year’s harvest. Overall cereal production substantially increased in all countries except Tanzania, where the current cereal forecast of 3.73 million tons is a 14% drop from last year’s output of 4.34 million tons. Of special note are the exceptionally large increases in the area planted in cereals in war-ravaged Angola and Mozambique, for the first time in many years. Production trebled in …


Moisture Deficit Index Evaluated For Dry Regions Of India, K. K. Nathan, S. K. Sinha Oct 1996

Moisture Deficit Index Evaluated For Dry Regions Of India, K. K. Nathan, S. K. Sinha

Drought Network News (1994-2001)

In India, about 70% of the cultivable land is rainfed. This includes areas where crops are rarely affected by drought and areas where crops experience moisture stress and often fail. The regions with the latter characteristics are often called dryland areas and the agriculture so practiced there is known as dryland agriculture. About 35% of the total cultivable land belongs in this category. To determine the magnitude of water deficiency in these regions, the moisture deficit index (MDI) has been evaluated for dryland stations in India. The MDI is usually determined on the basis of annual precipitation and annual potential …


Exploring The Potential For Using Enso Forecasts In The U.S. Corn Belt, Jennifer G. Phillips, Cynthia Rosenzweig, Mark Cane Oct 1996

Exploring The Potential For Using Enso Forecasts In The U.S. Corn Belt, Jennifer G. Phillips, Cynthia Rosenzweig, Mark Cane

Drought Network News (1994-2001)

Interannual climate variability poses the greatest risk that farmers face. Until recently, seasonal climate forecasts have been weak and therefore rarely observed by farmers in making management decisions. Farm management is generally based on long-term mean expectations of climate and crop responses to local edaphic conditions. Currently, significant progress is being made in the skill level of predictions of seasonal to interannual climate, primarily because of new understanding of the teleconnections between ocean circulation and atmospheric processes. The El Niño/Southern Oscillation (ENSO) refers to fluctuations in both sea-surface temperatures (SSTs) in the eastern equatorial Pacific and in sea-level pressures in …


Meteorological Drought In Turkey: A Historical Perspective, 1930-–93, Murat Türkes Oct 1996

Meteorological Drought In Turkey: A Historical Perspective, 1930-–93, Murat Türkes

Drought Network News (1994-2001)

The climate of Turkey, which is mainly characterized by the Mediterranean macro climate, results from the seasonal alternation of frontal depressions with polar air masses and subtropical high pressures with subsiding maritime tropical and continental tropical air masses. Continental tropical airstreams from the northern African and Arabian deserts particularly dominate throughout the summer, by causing long-lasting warm (hot) and dry conditions over Turkey (except the Black Sea region and northeastern Anatolia). Turkey has an area of 779,452 km2 and an average elevation of 1,132 m.

This study outlines some spatial and temporal characteristics of Turkey’s rainfall, particularly in terms …


Assessing The Impacts Of El Niño And Non-El Niño-Related Droughts Over India, R. H. Kripalani, Ashwini Kulkarni Oct 1996

Assessing The Impacts Of El Niño And Non-El Niño-Related Droughts Over India, R. H. Kripalani, Ashwini Kulkarni

Drought Network News (1994-2001)

It has now been recognized that the single most important key to the earth’s year-to-year climate variability is the El Niño/Southern Oscillation (ENSO) phenomenon. El Niño episodes directly affect the climate of at least half the planet and in many instances result in heavy loss of life and resources. The global impacts of El Niño events have been summarized in a review article by Bigg (1990), while the role of ENSO in Indian monsoon rainfall variability is given in Krishna Kumar et al. (1995). During the ENSO warm/ cold extremes—i.e., El Niño/La Niña events—the majority of the episodes induce below/above-normal …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 3. Lagrangian Drifters, J. R. Moisan, Eileen E. Hofmann Oct 1996

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 3. Lagrangian Drifters, J. R. Moisan, Eileen E. Hofmann

CCPO Publications

Two types of numerical Lagrangian drifter experiments were conducted, using a set of increasingly complex and sophisticated models, to investigate the processes associated with the plankton distributions in the California coastal transition zone (CTZ). The first experiment used a one-dimensional (1-D; vertical) time-dependent physical-bio-optical model, which contained a nine-component food web. Vertical velocities, along the track of simulated Lagrangian drifters, derived from a three-dimensional (3-D), primitive equation circulation model developed to simulate the flow observed within the CTZ; were used to parameterize the upwelling and downwelling processes. The second experiment used 880 simulated Lagrangian drifters from a 3-D primitive equation …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 1. A Time- And Depth-Dependent Model, J. R. Moisan, Eileen E. Hofmann Oct 1996

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 1. A Time- And Depth-Dependent Model, J. R. Moisan, Eileen E. Hofmann

CCPO Publications

A time- and depth-dependent, physical-bio-optical model was developed for the California coastal transition zone (CTZ) with the overall objective of understanding and quantifying the processes that contribute to the vertical and temporal development of nutrient and plankton distributions in the CTZ. The model food web components included silicate, nitrate, ammonium, two phytoplankton size fractions, copepods, doliolids, euphausiids, and a detritus pool. The wavelength-dependent subsurface irradiance field was attenuated by sea water and phytoplankton pigments. The one-dimensional (1-D) model adequately simulated the development and maintenance of a subsurface chlorophyll maximum in different regions within the CTZ. An analysis of the individual …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 2. A Three-Dimensional Physical-Bio-Optical Model, J. R. Moisan, Eileen E. Hofmann, D. B. Haidvogel Oct 1996

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone: 2. A Three-Dimensional Physical-Bio-Optical Model, J. R. Moisan, Eileen E. Hofmann, D. B. Haidvogel

CCPO Publications

A three-dimensional (3-D) primitive equation model, developed to simulate the circulation features (filaments) observed in the California coastal transition zone (CTZ), was coupled to a nine-component food web model and a bio-optical model. The simulated flow fields from a 3-D primitive equation model are used to advect the constituents of the food web model, which include silicate, nitrate, ammonium, two phytoplankton size fractions, copepods, doliolids, euphausiids, and a detritus pool. The bio-optical model simulates the wavelength-dependent attenuation of the subsurface irradiance field. The overall objective of this modeling study was to understand and quantify the processes that contribute to the …


Circulation, Fall 1996, Center For Coastal Physical Oceanography, Old Dominion University Oct 1996

Circulation, Fall 1996, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1996 issue of CCPO Circulation featuring article "Antarctic Continental Shelves Are Strange And Unique"


Diversity Of Arkansas Water Resources Research, Kenneth F. Steele Oct 1996

Diversity Of Arkansas Water Resources Research, Kenneth F. Steele

Technical Reports

In order to understand, protect, and manage our water resources effectively knowledge is required from many diverse areas of science, engineering, economics, and sociology. These proceedings of the conference on the Diversity of Arkansas Water Resources Research reflect this need and demonstrate how researchers in the state are responding to water issues and problems in Arkansas. The papers in these proceedings are representative of the research in Arkansas, but are only a sample of the work being conducted by universities and government agencies in Arkansas. We are grateful that Arkansas has the expertise available to provide the information necessary to …


Corals Of The South-West Indian Ocean Iv. The Hard Coral Family Faviidae Gregory, 1900 (Scleractinia: Faviina), Bernhard Riegl Oct 1996

Corals Of The South-West Indian Ocean Iv. The Hard Coral Family Faviidae Gregory, 1900 (Scleractinia: Faviina), Bernhard Riegl

Marine & Environmental Sciences Faculty Reports

This annotated check-list deals with the scleractinian coral family Faviidae in subtropical south-east Africa (the African mainland coast south of the Tropic of Capricorn). Material from the atoll Bassas da India in the Mozambique channel was included. Most species are of wide Indo-Pacific distribution. The faviid fauna of Mozambique was richer (28 species) than the South African fauna (21 species). The fauna of Bassas da India was similar to that on the African mainland coast with four additional species. South-east Africa has a moderately rich faviid fauna compared with other areas in the Indo-Pacific region. Field and laboratory characteristics are …


Seasonal And Inter-Annual Patterns Of Sediment-Water Nutrient And Oxygen Fluxes In Mobile Bay, Alabama (Usa): Regulating Factors And Ecological Significance., Jean L. Cowan, Jonathan Pennock, Walter R. Boynton Oct 1996

Seasonal And Inter-Annual Patterns Of Sediment-Water Nutrient And Oxygen Fluxes In Mobile Bay, Alabama (Usa): Regulating Factors And Ecological Significance., Jean L. Cowan, Jonathan Pennock, Walter R. Boynton

School of Marine Science and Ocean Engineering

Sediment oxygen and nutrient fluxes were measured monthly for 2 yr in Mobile Bay, Alabama, USA. Rates of sediment oxygen consumption (0.1 to 1.25 gO2 m-2 d-1), ammonium flux (-22 to 181 µmol m-2 h-1), nitrate flux (-14 to 67 µmol m-2 h-1), phosphate flux (-2 to 20.4 µmol m-2 h-1), and dissolved silicate flux (-15 to 342 µmol m-2 h-1) were moderate to high compared to values for other estuaries. A step-wise regression analysis revealed that dissolved oxygen concentration and temperature in bottom-waters …


Hermatypic Coral Fauna Of Subtropical Southeast Africa: A Checklist, Bernhard Riegl Oct 1996

Hermatypic Coral Fauna Of Subtropical Southeast Africa: A Checklist, Bernhard Riegl

Marine & Environmental Sciences Faculty Articles

The South African hermatypic coral fauna consists of 96 species in 42 scleractinian genera, one stoloniferous octocoral genus (Tubipora), and one hermatypic hydrocoral genus (Millepora). There are more species in southern Mozambique, with 151 species in 49 scleractinian genera, one stoloniferous octocoral (Tubipora musica L.), and one hydrocoral (Millepora exaesa [Forskal)). The eastern African coral faunas of Somalia, Kenya, Tanzania,
Mozambique, and South Africa are compared and Southeast Africa distinguished
as a biogeographic subregion, with six endemic species. Patterns of attenuation and species composition are described and compared with those on the eastern boundaries …


Depletion Of Atmospheric Nitrate And Chloride As A Consequence Of The Toba Volcanic Eruption, Q. Yang, Paul Andrew Mayewski, G. A. Zielinski, M. Twickler, K. C. Taylor Sep 1996

Depletion Of Atmospheric Nitrate And Chloride As A Consequence Of The Toba Volcanic Eruption, Q. Yang, Paul Andrew Mayewski, G. A. Zielinski, M. Twickler, K. C. Taylor

Earth Science Faculty Scholarship

Continuous measurements of SO42− and electrical conductivity (ECM) along the GISP2 ice core record the Toba mega‐eruption at a depth 2590.95 to 2091.25 m (71,000±5000 years ago). Major chemical species were analyzed at a resolution of 1 cm per sample for this section. An ∼6‐year long period with extremely high volcanic SO42− coincident with a 94% depletion of nitrate and 63% depletion of chloride is observed at the depth of the Toba horizon. Such a reduction of chloride in a volcanic layer preserved in an ice core has not been observed in any previous studies. The …