Ambient particulate matter (PM10) concentrations in major urban areas of Korea during 1996–2010

AbstractIn this study, ambient particulate matter pollution was investigated using monthly PM10 concentration data collected from seven major cities in Korea from 1996 to 2010. The highest mean value for the whole study period is seen from the capital city, Seoul (63.2±17.9μg m–3), while the lowest is from Ulsan (46.7±14.8μg m–3). The concentrations of PM10 in all cities exhibited seasonal variations with the peak values occurring consistently in spring (March or April). The PM10 data in each city consistently exhibited strong correlations (p<0.01) with gaseous pollutants (SO2, NO2, and CO), except for O3 (p>0.05). The analysis of long term trends of PM10 levels indicates a weak but consistent decline in concentrations in most cities with the relative average annual reductions of between 0.4 and 2.8% y–1

Photochemical assessment of oceanic emissions of DMS and its oxidation to SO₂ based on airborne field observations

Ph.D.Douglas D. Davi

Atmospheric input of nitrogen to the coastal region of southeastern Texas

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.inorganic nitrogen (DIN; NH4+, N03-), and dissolved organic nitrogen (DON) were measured in rainwater collected at three sampling sites (College Station, Houston, and Galveston, Texas). Dry deposition rate of nitrogen species was also measured in College Station. Concentrations of major ions, DIN, and DON in wet deposition samples collected in College Station depended on surface wind direction. High concentrations of most major ions in wet deposition correlated with winds from the northwest. In contrast, concentrations of DIN and DON from southern wind sectors (SE, S, SW, and W) were higher than those from northern wind sectors (NW, N, NE, and E). Anthropogenic sources significantly contributed to atmospheric nitrogen over Houston and this enhanced nitrogen affected the concentration of nitrogen species in College Station rain when the air mass came from the southern direction. In the coastal region (Galveston), concentrations of DIN and DON were significantly affected by marine sources, which diluted atmospheric nitrogen with sea-salt aerosol particles. Mean concentration and flux of DIN in College Station were 32.16︢3.4 limol I-I and II 81︢13 @Mol M-2 day-1, respectively. The mean concentration and flux of DON in College Station were 35.31︢04.7 gmol 1-1 and 1312︢47 IIMOI M-2 day-', respectively. These values were similar for DIN and DON. The isotopic data of rain nitrate and ammonium showed that the surface wind direction was a significant factor influencin

National Emissions of Greenhouse Gases and Air Pollutants from Commercial Aircraft in the Troposphere over South Korea

This study estimated greenhouse gas (GHG) and air pollutant emissions from aircraft in the troposphere (aircraft cruise altitudes, 1 - 12 km) over South Korea over a two-year period (2009 - 2010) using an activity-based (Landing and Take-Off (LTO) cycle) methodology. Both domestic and international LTOs covering 4 major airports and 11 smaller airports in South Korea were considered. The annual mean GHG emissions (CO2, N2O, CH4, and H2O) in the troposphere (1 - 12 km) over South Korea during the study period were approximately 3.5 ¡_ 103, 3.4 ¡_ 10-2, -6.6 ¡_ 10-2, and 1.4 ¡_ 103 kiloton (kt) yr-1, respectively. The tropospheric air pollutant emissions (CO, NOx, VOCs, and PM2.5) were approximately 3.0, 20, 1.0, and 0.2 kt yr-1, respectively. The monthly GHG and air pollutant emissions showed no significant variations. The GHG and air pollutant emissions during cruises over the South Korean airspace were significant contributors to (e.g., about 80% for NOx and about 75% for CO2) the total national aviation emissions including the emissions at airports, boundary layer and the free troposphere

Characteristics of Atmospheric Metalliferous Particles during Large-Scale Fireworks in Korea

The effect of large-scale firework events on urban background trace metal concentrations was investigated using 24 hr data collected over 3 days at three sites in Busan Metropolitan City, Republic of Korea, during the falls (Oct.) of 2011–2013. The firework events increased local background concentrations of trace metals as follows: K (1.72 times), Sr (2.64 times), As (2.86 times), Pb (2.91 times), and Al (5.44 times). The levels of some metals did not always drop to background level one day after the firework event. The contribution of fireworks to trace metal concentration levels (and emissions) for 2011 event was negligible compared to 2012 and 2013 events due to different meteorological conditions (precipitation). In addition, the impact of firework events on the ambient concentration levels of trace metals was likely to be different depending on their chemical speciation. The impact of firework events in Busan on urban air quality (trace metal) was less intense compared to other similar festivals worldwide. The largest emission of trace metals and elements from firework burning was represented by K (128–164 kg), followed by Pb, Cd, Cu, Mg, Ba, As, Al, Ga, Co, and Na

Air Pollution and Its Association with the Greenland Ice Sheet Melt

The Greenland Ice Sheet (GrIS) has been a topic of extensive scientific research over the past several decades due to the exponential increase in its melting. The relationship between air pollution and GrIS melting was reviewed based on local emission of air pollutants, atmospheric circulation, natural and anthropogenic forcing, and ground/satellite-based measurements. Among multiple factors responsible for accelerated ice melting, greenhouse gases have long been thought to be the main reason. However, it is suggested that air pollution is another piece of the puzzle for this phenomenon. In particular, black carbon (BC) and other aerosols emitted anthropogenically interact with clouds and ice in the Arctic hemisphere to shorten the cloud lifespan and to change the surface albedo through alteration of the radiative balance. The presence of pollution plumes lowers the extent of super cooling required for cloud freezing by about 4 &deg;C, while shortening the lifespan of clouds (e.g., by altering their free-energy barrier to prompt precipitation). Since the low-level clouds in the Arctic are 2&ndash;8 times more sensitive to air pollution (in terms of the radiative/microphysical properties) than other regions in the world, the melting of the GrIS can be stimulated by the reduction in cloud stability induced by air pollution. In this study, we reviewed the possible impact of air pollution on the melting of the GrIS in relation to meteorological processes and emission of light-absorbing impurities. Long-term variation of ground-based AERONET aerosol optical depth in Greenland supports the potential significance of local emission and long-range transport of air pollutants from Arctic circle and continents in the northern hemisphere in rapid GrIS melting trend

Emission and Cytotoxicity of Surgical Smoke: Cholesta-3,5-Diene Released from Pyrolysis of Prostate Tissue

Respiratory and lung irritants can be a by-product of the surgical pyrolysis of human tissues. Seven prostate tissues were collected during the transurethral resection of a prostate (TURP). Tissue samples, pyrolyzed in a pyrolysis sampling system, were collected and analyzed for the characterization of aerosols in the surgical smoke. In the pyrolyzed particulate matter (PM) from the TURP, Cholestra-3,5-diene was identified as the most dominant component along with 9-methylanthracene, hentriacontane, and dotriacontane based on the mass fragment structure determined using gas chromatography-mass spectrometry (GC-MS). As a molecular marker, Cholesta-3,5-diene can be associated with a cytotoxic in primary human oral keratinocytes (HOK). In this research, the presence of Cholestra-3,5-diene is reported for the first time as a by-product of surgical pyrolysis