Dust emission/deposition flux has been estimated using the gradient method with the two-level (3 and 15m high) measured PM(10) concentrations and the sonic anemometer measured momentum and kinematic heat fluxes at 8m high from a 20-m monitoring tower located at Naiman (Horqin desert) in the Asian dust source region in China for the winter of November 2007 to March 2008. The time series of measured PM(10) concentration at 3m high is used to identify the dust event and the non-dust event periods. It is found that the dust emission/deposition flux (F(C)) shows a significant diurnal variation with the maximum emission flux of 5.
View Article and Find Full Text PDFHourly mean time series of dust concentration (PM₁₀) measured at 3m high and a sonic-anemometer measured momentum and kinematic heat fluxes at 8m high above the surface have been obtained from a 20-m monitoring tower located at Erdene in the Asian dust source region of Mongolia for years of 2009 and 2010. These time series were used to identify dust events and to develop optimal regression equations for the dust concentration of dust events with the friction velocity (u(*)) and the convective velocity scale (w(*)). In total, 68 dust events were identified in 2009 (except for November) and 43 dust events for the period from March to August in 2010.
View Article and Find Full Text PDFThis study was performed to examine the relationship between particulate matter exposure and mortality in Seoul, Korea, during the year 2001. Particulate matter data were collected using an optical particle counter (OPC) and national monitoring stations in Seoul. The size-resolved aerosol number concentrations of particles 0.
View Article and Find Full Text PDFA single-particle analytical technique, named low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA), employing an ultrathin window X-ray detector and enabling the quantitative determination of even low-Z elements such as C, N, and O, is applied to characterize "Asian Dust" samples, collected in ChunCheon, Korea, during four Asian Dust storm events on March 7, 2000, April 7, 2000, March 22, 2001, and May 17, 2001. In this study, it is demonstrated that single-particle analysis using the low-Z particle EPMA provides detailed information on various types of chemical species in the samples. The most abundantly encountered particles, both in coarse and fine fractions, are aluminosilicates.
View Article and Find Full Text PDFThe Korean peninsula has a long history of dust clouds blown by winds from the arid deserts of Mongolia and China in springtime; these are called Asian dust events. Public concern about the possible adverse effects of this dust has increased, because the dust arrives in Korea after having passed over heavily industrialized eastern China. The present study explored the effect of Asian dust events on daily mortality in Seoul, South Korea, during the period 1995-1998.
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