Citation:

Kulkarni, S., N. Sobhani, J. Miller-Schulz, M. Shafer, J. Schauer, P. Solomon, P. Saide, S. Spak, Y. Cheng, H. Denier van der Gon, Z. Lu, D. Streets, G. Janssens-Maenhout, C. Wiedinmyer, J. Lantz, M. Artamonova, B. Chen, S. Imashev, L. Sverdlik, J. Deminter, B. Adhikary, A. D'Allura, C. Wei, AND G. Carmichael. Source Sector and Region Contributions to BC and PM2.5 in Central Asia. Atmospheric Chemistry and Physics. Copernicus Publications, Katlenburg-Lindau, Germany, 15(4):1683-1705, (2015).

Impact/Purpose:

The National Exposure Research Laboratory’s (NERL’s) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA’s mission to protect human health and the environment. HEASD’s research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA’s strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose. The impact of these tools is improved regulatory programs and policies for EPA.

Description:

Particulate matter (PM) mass concentrations, seasonal cycles, source sector and source region contributions in Central Asia (CA) are analyzed for the period April 2008-July 2009 using the STEM chemical transport model and modeled meteorology from the WRF model. Predicted AOD values (annual mean value ~0.2) in CA vary seasonally with lowest values in the winter. Surface PM_2.5 concentrations (annual mean value ~10 µg/m³ )also exhibit a seasonal cycle, with peak values and largest variability in the spring/summer, and lowest values and variability in the winter (hourly values from 2 – 90 mg/m³). Surface concentrations of BC (mean value ~0.1 µg/m) show peak values in the winter. Dust, from sources within and outside CA, is a significant component of the PM mass and drives the seasonal cycles of PM and AOD. On an annual basis, the power and industrial sectors are found to be the most important contributors to the anthropogenic portion of PM_2.5. Residential combustion and transportation are shown to be the most important sectors for BC. Biomass burning within and outside the region also contributes to elevated PM and BC concentrations. The simulated values are compared to surface measurements of Aerosol Optical Depth (AOD), and PM_2.5, PM₁₀, black carbon (BC), organic carbon (OC) mass concentrations at two regional sites in the Kyrgyz Republic (Lidar Station Teplokluchenka (LST) and Bishkek). The predicted values of AOD and PM mass concentrations and their seasonal cycles are fairly well captured. The carbonaceous aerosols are under predicted in winter, and analysis suggests that the winter heating emissions are underestimated in the current inventory. The analysis of the transport pathways and the variations in particulate matter mass and composition in CA demonstrate that this region is strategically located to characterize regional and intercontinental transport of pollutants. Aerosols at these sites are shown to reflect dust, biomass burning and anthropogenic sources from Europe, South, East and Central Asia, and Russia depending on the time period. Simulations for a reference 2030 emission scenario based on pollution abatement measures already committed to in current legislation show that PM_2.5 and BC concentrations in the region increase, with BC growing more than PM_2.5 on a relative basis. This suggests that both the health impacts and the climate warming associated with these particles may increase over the next decades unless additional control measures are taken. The importance of observations in CA to help characterize the changes that are rapidly taking place in the region are discussed.

URLs/Downloads:

FINAL FINAL CENASIAPAPER_TEXTFIGS_CLEAN_V28AUG2014_NOYELLOW.PDF  (PDF, NA pp,  7237.769  KB,  about PDF)

Atmospheric Chemistry and Physics  

Record Details:

Record Type:DOCUMENT( JOURNAL/ PEER REVIEWED JOURNAL)

Product Published Date:02/18/2015

Record Last Revised:02/25/2015

OMB Category:Other

Record ID: 306911

Show Additional Record Data