Characteristics of Aerosol Particulate Matter in Kyrgyzstan: Advancing our Understanding of Regional Transport of Atmospheric Aerosol in Central Asia
MARTIN SHAFER (1), James Schauer (1), Paul Solomon (2), Jeffrey Lantz (3), Maria Artamonova (4), Boris Chen (5), Sanjar Imashev (5), Leonid Sverdlik (5), Greg Carmichael (6), Jeff Deminter (7), Justin Miller-Schulze (1)
(1) University of Wisconsin-Madison, Madison WI, (2) U.S. EPA, ORD, Las Vegas NV, (3) U.S. EPA, ORIA, Las Vegas NV, (4) Institute of Atmospheric Physics, Moscow, Russia, (5) Kyrgyz-Russian Slavic University, Bishkek, Kyrgyz Republic, (6) University of Iowa, Iowa City, IA, (7) Wisconsin State Laboratory of Hygiene, Madison WI.
Abstract Number: 185
Preference: No preference
Last modified: November 8, 2009
Working Group: sq3
To advance our understanding of regional and long-range transport of aerosol particulate matter (PM) from Central Asia to East Asia, South Asia, the Pacific Ocean, and North America we are characterizing sources of PM from Central Asia. A particular focus of our effort is on PM sourced from the Aral Sea region of southern Kazakhstan and northern Uzbekistan, the third largest source of mineral dust in Asia. Until this study, the information on particulate matter from this region of Asia available to support these source reconciliation and modeling efforts was extremely limited. We established two monitoring stations in the Kyrgyz Republic, where PM10 and PM2.5 samples were collected every other day from July 2008 through July 2009 for detailed chemical analysis. The two sites, one in Bishkek, the capital, the other in Karakol in eastern Kyrgyzstan are located 1000 and 1200 km east of the Aral Sea, respectively. Measurements at both sites include an FDMS TEOM to quantify fine particulate matter (PM) on an hourly basis, and 24-hr integrated filter-based samples for fine mass, organic carbon (OC), elemental carbon, ions, trace elements by ICP-MS, and a large suite of organic species, including source apportionment molecular markers and secondary organic tracers. Data from a LIDAR located at the Karakol site, will be used for aerosol backscatter measurements. Soil samples were also obtained from the vicinity of the aerosol monitoring sites and from 10 locations surrounding the Aral Sea. These soils were resuspended and PM10 and PM2.5 fractions sampled for detailed chemical finger-printing.The year-long aerosol sampling effort captured a series of multi-day dust events, occurring primarily in spring and summer, with high temporal concurrence between the two sampling sites. Relatively high PM levels in the warmer months were supported by large contributions of inorganic aerosol components, which declined dramatically in October, with a resultant shift to a more carbonaceous aerosol population in Fall and Winter. OC concentrations were typically highest in summer; however the OC/EC ratio exhibited a large and progressive decline from summer into fall, reflecting at the Bishkek site primarily a decrease in OC levels and at the Lidar site a substantial increase in EC concentrations. At both sites a striking decline in the contribution of coarse OC to total OC was observed in moving from summer to winter. Levels and contributions of semi-volatile species (as measured by the TEOM) were greater in the warmer months, suggesting significant secondary aerosol formation during this period. Important new information on baseline and event contribution of both inorganic and carbonaceous aerosol components to PM traversing Central and Eastern Asia will result from the study. These data will support receptor and Eulerian modeling to estimate the impact of Asian dust transport from the Aral Sea to Kyrgyzstan and from Central Asia to China and further East.
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