Atmospheric Impacts due to Anthropogenic Activities in Remote Areas: The Case Study of Admiralty Bay/King George Island/Antarctic Peninsula

The aim of the present work is to characterize the local atmospheric emissions levels and compare them to the component derived from global pollution in a remote site at South Hemisphere (Admiralty Bay located at King George Island in Antarctic Peninsula). Airborne particles, snow and soil/sediments samples were analyzed. Local-produced atmospheric aerosol dispersion was estimated for metals originated by fossil fuel burning from the permanent scientific stations using a simplified Gaussian model. Validation of atmospheric dispersion was established by in situ measurements. Soluble and insoluble particles deposited in freshly snow and airborne particles were analyzed by PIXE (Particle Induced X-Ray Emission) for the determination of the elemental mass concentration and to obtain the Mass Median Aerodynamic Diameter (MMAD). The results showed significant correlation between the concentration of atmospheric aerosol and the freshly deposited particles in the snow, and permitted an estimate of the atmospheric snow deposition factor for K, Cu, Zn, Fe, Pb, and Ti. Results of long-term aerosol data compilation suggest that besides the local aerosol sources, the continental atmospheric transport of airborne particles is not significantly affected by the airborne particles produced by local human impacts at King George Island.     

Size Distributions and Concentrations of Spheroidal Carbonaceous Fly-Ash Particles (SCPs) in Lake Sediments as an Aid to Detecting Locally Deposited Atmospheric Pollution

Size distributions and concentrations of spheroidal carbonaceous fly-ash particles (SCPs) > 5 μm have been counted in surface sediments from 20 lakes along a 62 km west-east transect in the Bergen area, Norway. Increased concentrations of SCPs are found in lakes immediately downwind, closest to the city. These lakes also have a dominance of larger particles (> 10 μm) than further downwind where smaller particles (5–10 μm) dominate. The pattern of SCPs > 5 μm is compared with a previous study of anthropogenic Pb and SCPs > 3 μm in the same sediments. Along the transect there is a difference in pattern between the concentrations of SCPs > 5 μm and the patterns of anthropogenic Pb and SCPs > 3 μm. The result indicates that increased altitude and rainfall probably explain the increased concentrations of anthropogenic Pb and SCPs > 3μm in the eastern part of the transect. Metals are in the size range for which atmospheric residence times are greatest, whereas particles > 5 μm in diameter are of the size thought to be effectively removed from the atmosphere by sedimentation. This may explain, at least partially, why there is a difference between the pattern of SCPs > 5 μm concentrations and anthropogenic Pb and SCPs > 3 μm concentrations. This study shows that SCPs > 5 μm in lake sediments can potentially provide a better signal of locally-deposited atmospheric pollution than trace elements from the same source. A SCP distribution dominated by large particles (> 10 μm) is found up to 20 km downwind of the city. Within this area, temporal SCP size distribution patterns can help detect local-deposited atmospheric pollution.     

东亚季风与城市活动影响下南京市大气沉降多元特征研究

Atmospheric deposition, a major pathway of metals entering into soils, plays an important role in soil environment, especially in urban regions where a large amount of pollutants are emitted into atmosphere through various sources. In order to understand the characteristics of atmospheric deposition in urban area and its relation with natural and anthropogenic sources, a three-year study of atmospheric deposition at three typical sites, industrial zone (IN), urban residential area (RZ) and suburban forested scenic area (FA), was carried out in Nanjing, a metropolitan city in eastern China from 2005 to 2007. The bulk deposition rate and element composition of atmospheric deposition varied spatio-temporally in the urban zones of Nanjing. The concentrations of Cu, Zn, Pb and Ca in the atmospheric deposits were strongly enriched in the whole Nanjing region; however, anthropogenic pollutants in atmospheric deposits were diluted by the input of external mineral dust transported from northwestern China. Source apportionment through principal component analysis (PCA) showed that the background atmospheric deposition at the FA site was the combination of external aerosol and local emission sources. The input of long-range transported Asian dust had an important influence on the urban background deposition, especially in spring when the continental dust from the northwestern China prevailed. Marine aerosol source was observed in summer and autumn, the seasons dominated by summer monsoon in Nanjing. In contrast, the contribution of local anthropogenic emission source was constant regardless of seasons. At the RZ and IN sites, the atmospheric deposition was more significantly affected by the nearby human activities than at the FA site. In addition, different urban activities and both the winter and summer Asian monsoons had substantial impacts on the characteristics of dust deposition in urban Nanjing.     

Empirical modeling of spatial and temporal variation in warm season nocturnal air temperatures in two North Idaho mountain ranges, USA

Accurate, fine spatial resolution predictions of surface air temperatures are critical for understanding many hydrologic and ecological processes. This study examines the spatial and temporal variability in nocturnal air temperatures across a mountainous region of Northern Idaho. Principal components analysis (PCA) was applied to a network of 70 Hobo temperature loggers systematically distributed across 2 mountain ranges. Four interpretable modes of variability were observed in average nighttime temperatures among Hobo sites: (1) regional/synoptic; (2) topoclimatic; (3) land surface feedback; (4) canopy cover and vegetation. PC time series captured temporal variability in nighttime temperatures and showed strong relationships with regional air temperatures, sky conditions and atmospheric pressure. PC2 captured the topographic variation among temperatures. A cold air drainage index was created by predicting PC2 loadings to elevation, slope position and dissection indices. Nightly temperature maps were produced by applying PC time series back to the PC2 loading surface, revealing complex temporal and spatial variation in nighttime temperatures. Further development of both physically and empirically based daily temperature models that account for synoptic atmospheric controls on fine-scale temperature variability in mountain ecosystems are needed to guide future monitoring efforts aimed at assessing the impact of climate change.     

Evolution, Sources and Distribution of Mineral Particles and Amorphous Phase of Atmospheric Aerosol in An Industrial and Mediterranean Coastal Area

The aim of this work is to propose a methodology that helps to learn about the distribution of different types of solid compounds in atmospheric aerosol, collected in an industrial area located in a Mediterranean basin that produces mineral raw materials. The work is developed from TSP samples collected daily in an open area near a ceramic production facility with a High Volume TSP sampler. The sampler permits the collection of sufficient daily quantities of particulate sample for subsequent X-ray diffraction characterisation and quantification. The results have shown that atmospheric aerosol in the area are dominated by particles coming from combustion processes, mainly vehicular traffic, and dust emissions originating when raw materials are transferred and treated. Combustion particles present a seasonal evolution. Mineral particles are mainly dependent upon weekly industrial activity and their contents suffer high increases during periods of atmospheric particle accumulation which are produced when certain meteorological conditions exist. Data have also shown an approximation of the particle distribution in aerosol from different source origins (vehicular traffic, dust emissions, secondary formation, marine aerosols). During days with intermediate pollution levels (which suppose 60% of the total) combustion particles compromise around 55 to 60% of the TSP while mineral particles coming from industrial dust emissions make up 20% of the TSP. In time intervals of atmospheric particulate accumulation these particle levels in the air can reach the legislated guideline values. During these episodes, mineral contents coming mainly from dust emissions compromise more than the 50% of the aerosol.     

Characterization of Atmospheric Aerosol in the Northern Foot of Mt. Fuji, Central Japan

The unique characteristics of atmospheric aerosol in the northern foot of Mt. Fuji, central Japan were first clarified. The Mt. Fuji (an altitute of 3776 m) is the largest basaltic stratovolcano in the quaternary period in Japan. The aerosol measurements were carried out at an altitute of 1100 m from June 2000 to April 2001. Ambient aerosol in the predominant area of a typical volcanic rock like basalt was referred to as a basaltic aerosol in this study. Fifteen elements (Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Ba, Pb) of major to trace in the aerosol samples were determined by X-ray fluorescence spectrometry. Total mass concentration (< 10 μm) of the basaltic aerosol showed the higher values in summer and spring rather than autumn to winter, and the seasonal variation pattern differed widely from that of general urban aerosol. The behavior of the basaltic aerosol was mainly controlled by mineral particles throughout the year, so that a typical anthropogenic-derived element like Pb was very rarely detected. Even V, Cr and Zn which have been generally considered to be typical anthropogenic-derived elements, showed crustal-like behaviors. A concentration ratio of Si/Al showed markedly a uniqueness of the basaltic aerosol. From a comparison with atmospheric aerosol Si/Al ratio in granitic region being an exact opposite geology, a correlation plot of Si/Al ratio against Si concentration was made. It showed a big regional difference available for source identification of atmospheric soil particles. The chemical and geological characteristics of the basaltic aerosol are very useful for the novel characterization of atmospheric soil particles.     

Variation in the geochemistry of recent lake sediments along a west east pollution gradient in the Bergen area, Norway

Twenty nine lakes were sampled on a 62 km long west-east transect near Bergen, Norway from Sotra in the west to Norheimsund in the east. Top and bottom samples of 29 sediment cores, 20–40 cm long, were collected and 17 chemical elements were measured. Sphaeroidal carbonaceous particles from fossil fuel origin were counted in the surface sediments. The study was designed to answer two questions: (1) Does lake-sediment composition reflect variations in local atmospheric pollution? (2) What factors explain the observed variation in concentration of chemical elements along this transect? Ca, Cr, Mg, and Ni concentrations along the transect appear to result from differences in the content of these elements in bedrock. Hg, Pb, and Zn concentrations in the top sediments are dominated by input from anthropogenic sources. Variation of Cd, Fe, and Zn in the top sediments seems to be dependent on variation in lake-water pH. Hg and Zn from anthropogenic sources probably result from long-transported pollution. Pb and carbonaceous particles from anthropogenic sources possibly have a local origin.     

Mercury in swedish forest soils and waters — Assessment of critical load

As a result of air pollution, the content of Hg in fish has significantly increased in a large part of Scandinavia and North America. In this paper, the occurence and fluxes of Hg in Swedish forest soils and waters are reviewed and synthesized. The main objective is to describe and evaluate the present transport of anthropogenic Hg from atmospheric deposition, through the terrestrial compartment and running waters to lake basins and also to comprehend the main factors influencing these fluxes. The transportation and distribution. of Hg in forest soils and waters is closely related to the flow of organic matter. The content of Hg in humic matter is higher in southern and central areas compared to the north of the country. Compared to background concentrations, the Hg content has increased in the southern and central part by about a factor of 4–7, while the overall increase in the north is by about a factor of 2 to 3. The increased content of Hg in forest soils may have an effect on organisms and biological processes in the soil. Regarding budget calculations for whole catchment areas and for the mor layer of the soil, a reduction of about 80% from present atmospheric wet deposition must be obtained to reach “critical load” with respect to conditions in Scandinavia.     

Observations of Visibility and Chemical Compositions Related to Fog,Mist and Haze in South Korea

Since 1970, the yearly consumption of fossil fuel in south Korea has steadily increased to 165 MT from 14 MT. It has been found that the number of days of low visibility (≤10 km) was significantly increased by the occurrence of fog, mist and haze. For example, the low visibility days in Seoul during 1989 were over 207 days in comparison with 21 days at a rural site. This similar trend has been observed in other large cities. In Chongwon of central Korea, daily measurements of visibility at 09 LST have been made since 1991. It is observed that the increase in the frequency of low visibility days was related to the increase in anthropogenic air pollution and water vapor in the study area. The occurrence of fog-mist-haze was much related to the influence of local, regional and synoptic meteorology. With the increase in both water supply and emission of air pollution, in Korea we commonly observe the typical historical type of London mist and haze. In this study, chemical analyses of fog, mist, haze and frost was carried out. According to analyses of data obtained in 1995, the pH values for 65.9% of all fog and mist samples collected were less than 5.6. The lowest pH value of fog was 4.0. On the other hand, pH values observed for dew and frost in early spring were generally neutral to alkaline in nature, although there was an abundant existence of sulphates and nitrates. This suggests that characteristics of yellow sand and soil dust occurring in spring appear to determine the pH values in hydrometeors occurring on the Korean peninsula. A satellite observation of sea fog is also discussed. It has been observed that the advection fog occurred with air pollutants over the Yellow Sea which were moving out of China.     

Computer Simulation of the Transport,Formation and Dynamics of Atmospheric Sulfate Particles

The present paper investigates the transport, formation and dynamics of atmospheric sulfate particles under different meteorological conditions from point sources. Emissions of SO2 from one and multiple local point sources were modeled. The advection and diffusion of gaseous and particulate matter are described by the atmospheric diffusion equation which is solved numerically using a new developed 3-dimensional model. The evolution of the aerosol size distribution with time was described using the aerosol general dynamic equation. Under fog conditions aqueous phase oxidation is the primary mechanism for sulfate formation. The condensation mechanism from the vapor to liquid phase is the dominant process for sulfate production at moderate relative humidities. The observed mass size distribution of sulfate suggests that the major contribution in the mass size distribution during continental conditions is from long range transport.     

Trace Element Profiles in Ombrogenous Peat Cores from Norway: Evidence of Long Range Atmospheric Transport

Concentrations of Pb, Cd, As, Sb, and Se in peat from 21 ombrotrophic bogs in Norway are discussed with respect to air pollution and compared to other evidence from studies of trace element deposition in Norway. In general the data support conclusions from studies of atmospheric deposition based on moss analysis, and they also confirm specific trends previously observed for the contamination of natural surface soils with these elements. Lead, Cd, As, and Sb all are strongly enriched in the surface peat layers, indicating significant atmospheric input all over the country. In the south the concentrations in the surface peat are about 10 times higher than in the central and northern part of the country, supporting previous evidence of substantial input from source regions in other European countries. For Se there is also a component of anthropogenic input in the south, but this contribution from long range transport is superimposed on a very distinct coast - inland gradient all along the west coast, strongly suggesting atmospheric supply of Se from the marine environment.     

Material Damage Caused by Acidic Air Pollution in East Asia

Atmospheric and laboratory corrosion tests were carried out to assess the intensity of air pollution in East Asia. Qualitative and quantitative atmospheric corrosion was estimated from the damage caused to bronze, copper, steel, marble, cedar, cypress and urushi (Japanese lacquer) plates, exposed to outdoor and indoor airs in some cities of East Asia. Brochantite and cuprite were formed on copper at sites where the sulfur dioxide concentrations were high, and basic cupric nitrate and cuprite at sites where nitrogen dioxide concentrations were high. Gypsum was formed on marble pieces exposed to indoor air at all sites but was not found on pieces exposed to outdoor air. Numerous fine spots (0.2–0.3 mm in diameter) were observed on surfaces of urushi plates exposed at foggy cities such as Chongqing, China and Taejon, Korea. The effects of atmospheric and meteorological factors on the damage to copper and marble plates in several cities in East Asia were estimated using regression analysis. The results indicate that sulfur dioxide is the most destructive of materials especially in China and South Korea. In Japan copper plates may be damaged under natural conditions and by sea salt. Copper may also be damaged by surface deposition of sulfur and chlorine. Marble may be substantially degraded by gaseous sulfur dioxide but sulfate ions in rain had no effect. The analysis of air pollution from the point of view of material damage was very useful in evaluating and visualizing the intensity of air pollution in East Asia.     

Does a Synoptic Classification Indicate the NO x Pollution Potential? The Case of the Metropolitan Area of Tel Aviv, Israel

This study examines the synoptic conditions controlling NO _x pollution in the metropolitan area of Tel Aviv, using a semi-objective synoptic classification for the eastern Mediterranean. A day in which NO _x concentration exceeded the Israeli standard in ≥1 of the seven monitoring stations was defined an “exceeding day” and in ≥5 as an “extensive exceeding day”. For 1998–2004, 19% and 3% of the days were found exceeding and extensive exceeding days, respectively, over 85% of them in the winter months, November–March. The inter-annual variation in the occurrence of the synoptic types was found to explain 72% of the variations in the number of exceeding days. A significant negative trend in the occurrence of types with high pollution potential explained the decrease of 10% per year in the number of exceeding days during 1998–2004. The Red Sea Trough, though being cyclonic system, contributed 51% of the exceeding days, while highs, though being more frequent, contributed only 35%. The “pollution potential” of a synoptic type was defined as the percentage of exceeding days belonging to this type. The majority of synoptic types with the highest pollution potential were cyclonic, most being the Red Sea Trough with western axis, with 82% potential. Our findings indicate that the identity of the synoptic system as cyclonic or anticyclonic is not the key factor for the pollution potential in the study region, but rather, the ambient atmospheric conditions they induce, i.e., high temperatures, static stability, and weak easterly offshore flow. Local processes are the direct cause of the pollution and that the role of the synoptic conditions is to enable, or even to reinforce, the supportive meso-scale processes. This study is a first step in downscaling synoptic features to local NO _x pollution potential, constituting a basis for alarming against pollution events, based on the predicted synoptic conditions.     

Aerosol composition of urban and desert origin in the eastern Mediterranean

Monthly dustfall samples collected in 16 sites in the Tel-Aviv urban areas, as well as those collected in 10 rural sites in Israel during several years of measurements, were analyzed for their physical properties and chemical content. Although dustfall measurements represent a very simple and crude technique the analysis of the data provides some very interesting conclusions: (a) The southwest part of Israel, which is scarcely populated, suffers from high dustfall values due to dust storm blowing from the Sahara and other arid lands to the east Mediterranean during the spring. (b) On an annual basis the natural dustfall of dust storms origin amounts to 25 to 30% of the Tel-Aviv residential area deposition or 3 to 4 tonne km^?2 mo^?1. (c) Mapping of dustfall data within an urban region reflects fairly well the main industrial and commercial activities within the city. (d) In residential areas the inorganic water insoluble fraction of the dust is contributed by natural sources, while the organic fraction is mostly of anthropogenic origin. The inorganic water soluble fraction is spread in a uniform pattern within the city.     

Effects of varying air trajectories on spatial and temporal precipitation chemistry patterns

This study was designed to determine if judicious use of synoptic data and an operational trajectory model could identify probable source regions of anthropogenic pollutants in northeastern United States precipitation and thus relate receptor measurements to emissions data without consideration of the complex intervening meteorological and chemical processes. The storm event of April 8 to 10, 1979, was selected for intensive study. Precipitation chemistry data were obtained from event samples at six MAP3S sampling sites and from hourly samples at Brookhaven National Laboratory. Concentrations of hydrogen, sulfate, nitrate and ammonium ions were used as receptor data. Some emissions data for SO_x and NO_x were obtained from the MAP3S emissions inventory. Surface and upper air meteorological data were analyzed. Backward trajectories ending at each of the sampling sites during the precipitation period were computed with the Heffter Interactive-Terminal Transport Model using selected transport layers. Results show that concentrations of pollutant species in event precipitation samples were much higher at stations at end points of trajectories passing through the Ohio River valley than at stations with other trajectories. Likewise, concentrations at Brookhaven were much higher during the end period of a trajectory through the same region than with more northerly and more southerly tracks. The model produced back trajectories consistent with synoptic flows. Concentrations of air pollutants in precipitation were roughly proportional to the number of major pollutant sources along the trajectory. These results suggest that a larger number of studies might identify more restricted source areas or even establish a quantitative relationship between source emissions along a trajectory and concentrations in precipitation at receptor sites.     

THE TRAPPING OF FLY-ASH PARTICLES IN THE SURFACE LAYERS OF SPHAGNUM-DOMINATED PEAT

The movement of fly-ash particles in a sequence ofSphagnum moss was studied in laboratory experiments and field investigations. The data obtained in the laboratory show that only 0.8% of particles, placed on the surface of a 6–10 cm thickSphagnum layer, were washed out with water (700–750 mm) during the 241 days of the experiment. The majority of added particles were fixed in the upper part (90% in 1–3 cm) of the moss layer. A SEM study indicates that sorption is slightly species-dependent due to the micromorphological parameters of theSphagnum species. The storage of particles bySphagnum mosses allows the use of natural sequences to study the history of atmospheric pollution. The distribution of particles in the upper part of moss layers in Viru Bog (50 km east of Tallinn, North Estonia) shows good agreement with the known air pollution history in Tallinn.     

Atmospheric deposition of mercury in Florida: The fams project (1992–1994)

The primary goal of the Florida Atmospheric Mercury Study (FAMS) is to quantify the seasonal and geographical variability in the atmospheric deposition of Hg and other trace elements in central and south Florida. Precipitation, aerosol, and gaseous Hg samples have been collected at seven sites in Florida for periods ranging from 3 to 24 months. The summertime wet season in south Florida accounts for 80 to 90% of the annual rainfall Hg deposition. Depositional rates in south Florida are 30 to 50% higher than those from central Florida. Particle phase measurements range from 2 to 18 pg/m³Hg at all sites. Measurements of monomethylmercury in precipitation range from <0.005 to 0.020 ng/L.     

Transformation processes involving mercury species in the atmosphere — results from a literature survey

Mercury is released into the atmosphere from natural and anthropogenic sources. Once in the air, Hg species will be dispersed, chemically and physically transformed, and transported over varying distances (regional, continental and global scales) while concurrently being subjected to removal processes. Modeling of the aerial transport and deposition of Hg to receptor sites offers an attractive approach for integrating existing experimental data and represents an important tool for advancing our understanding of environmental Hg pollution. Comprehensive modeling efforts of the atmospheric pathways and fate of this heavy metal require knowledge of its atmospheric chemistry. To update and consolidate available information relevant to the atmospheric chemistry of Hg, a computer-assisted search was undertaken of the primary scientific literature published during the last ten years. Selected results from this literature survey are presented in this paper.     

Comparison of aerosol sulfur and crustal element concentrations in particle size fractions from continental U.S. locations

A comparison of element concentrations in aerosols is made for S, Si, K, Ca, Ti, Fe, and Zn as a function of particle size during April 1976 in nonurban New Mexico, Colorado, and New Hampshire and urban and nearby rural St Louis, Missouri. In the submicrometer diameter range at all sites, S greatly exceeds Si, K, Ca, Ti, and Fe, which occur predominantly in the coarse particle (>1 μm) fraction. Particle size distributions of each of these elements are similar among the five sites, but prominent concentration anomalies and secondary size distribution differences are measureable and suggest differences in aerosol production processes and relative pollution source strengths. The results are potentially useful in evaluating causes of atmospheric visibility differences between the western and eastern U.S.A.