Spatiotemporal Analysis of Black Carbon Sources: Case of Santiago, Chile
Jessika Rodriguez, HECTOR JORQUERA,
Pontificia Universidad Catolica de Chile Abstract Number: 274
Working Group: Carbonaceous Aerosol
AbstractThe use of aethalometers generates useful information on carbonaceous aerosols. Specifically, the aethalometer model provides an apportionment of black carbon (BC) from fossil fuels and wood burning sources. At any given receptor site, this apportionment is aggregated, that is, local and regional BC sources are lumped together in the outcome of the aethalometer analysis. However, for regulatory purposes, it is desirable to have quantitative estimates of both contributions. This is particularly relevant for remote locations or suburban monitoring sites.
We propose a spatiotemporal analysis of BC aethalometer results which is based on ambient measurements of BC fractions (fossil fuel plus wood burning) along with meteorological information. We apply this methodology to BC measurements in three suburban sites surrounding Santiago, Chile. The results show that the methodology can apportion BC
ff and BC
wb into local and regional contributions. By using PM2.5 – BC
X scatterplots for each spatiotemporal pattern, the associated edge lines show distinctive BC
X/PM2.5 ratios: they are larger for the local sources (fresh emissions) than for the regional contribution (Santiago’s atmospherically processed emissions). These ratios are then used to apportion total PM
2.5 at each monitoring site.
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