Elemental and Molecular Evidence of Soot- and Char-Derived Black Carbon Inputs to New York City's Atmosphere during the 20th Century
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- 作者：Patrick Louchouarn ; Steven N. Chillrud ; Stephane Houel ; Beizhan Yan ; Damon Chaky ; Cornelia Rumpel ; Claude Largeau ; Gerard Bardoux ; Dan Walsh ; Richard F. Bopp
- 刊名：Environmental Science & Technology
- 出版年：2007
- 出版时间：January 1, 2007
- 年：2007
- 卷：41
- 期：1
- 页码：82 - 87
- 全文大小：141K
- 年卷期：v.41,no.1(January 1, 2007)
- ISSN：1520-5851
文摘
Soot black carbon (here expressed as GBC) is present insediments of Central Park and Prospect Park Lakes, NewYork City (NYC), and peaks in the middle of the 20thCentury at the highest values (1-3% dry weight) everreported in urban lakes. During that period (~1940-1970),the GBC represents up to 28% of the total organiccarbon (OC). Radionuclide-normalized whole core inventoriesof accumulated GBC are similar in the two lakes whichare separated by ~15 km, suggesting that emissions of finesoot particles may have accumulated homogeneouslyover at least the urban center of NYC. The distribution ofpolycyclic aromatic hydrocarbons (PAHs) in the sedimentsis decoupled from that of GBC. The highest levels of totalPAHs correspond to peak coal use for space heating inNYC in the early 1900s. In contrast, GBC concentrations werehighest in the mid 1900s, a period when oil combustiondominated local fossil fuel use and incineration of municipalsolid waste (MSW) was common practice in NYC.Decreases in GBC levels observed in more recentlydeposited sediments are consistent with improvements inparticle emissions control systems. Non-soot BC (char)was identified by a high carbon to nitrogen (C/N) ratio thatpersisted after correction for GBC. This likely tracer ofMSW incineration was estimated to contribute an additional~35% of total organic carbon found in the sedimentsdeposited during the peak period of combustion. Thetemporal trends of soot-BC observed in our lake cores donot agree with published historical reconstructionsbased on fuel consumption and estimated emission factors.