Changes in the levels and variability of halocarbons and the compliance with the Montreal Protocol from an urban view

Chang-Feng Ou-Yang; Chih-Chung Chang; Shen-Po Chen; Clock Chew; Bo-Ru Lee; Chih-Yuan Chang; Stephen A Montzka; Geoffrey S Dutton; James H Butler; James W Elkins; Jia-Lin Wang

doi:10.1016/j.chemosphere.2015.06.070

Changes in the levels and variability of halocarbons and the compliance with the Montreal Protocol from an urban view

Chemosphere. 2015 Nov:138:438-46. doi: 10.1016/j.chemosphere.2015.06.070. Epub 2015 Jul 6.

Authors

Affiliations

¹ Department of Chemistry, National Central University, Taoyuan 32001, Taiwan; Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan.
² Research Center for Environmental Changes, Academia Sinica, Taipei 11529, Taiwan. Electronic address: joechang@rcec.sinica.edu.tw.
³ Department of Chemistry, National Central University, Taoyuan 32001, Taiwan.
⁴ Research Center for Environmental Changes, Academia Sinica, Taipei 11529, Taiwan.
⁵ Global Monitoring Division, Earth Systems Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, United States.
⁶ Global Monitoring Division, Earth Systems Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, United States; Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, United States.
⁷ Department of Chemistry, National Central University, Taoyuan 32001, Taiwan. Electronic address: cwang@cc.ncu.edu.tw.

PMID: 26160300
DOI: 10.1016/j.chemosphere.2015.06.070

Abstract

Ambient levels and variability of major atmospheric halocarbons, i.e. CFC-12, CFC-11, CFC-113, CCl4, CH3CCl3, C2HCl3, and C2Cl4 in a major metropolis (Taipei, Taiwan) were re-investigated after fourteen years by flask sampling in 2012. Our data indicates that the variability expressed as standard deviations (SD) of CFC-113 and CCl4 remained small (2.0 ppt and 1.9 ppt, respectively) for the 10th-90th percentile range in both sampling periods; whereas the variability of CFC-12, CFC-11, C2HCl3, and C2Cl4 measured in 2012 became noticeably smaller than observed in 1998, suggesting their emissions were reduced over time. By comparing with the background data of a global network (NOAA/ESRL/GMD baseline observatories), the ambient levels and distribution of these major halocarbons in Taipei approximated those at a background site (Mauna Loa) in 2012, suggesting that the fingerprint of the major halocarbons in a used-to-be prominent source area has gradually approached to that of the background atmosphere.

Keywords: Halocarbons; Montreal Protocol; Ozone-depleting substances (ODS); Variability.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants / analysis*
Atmosphere / chemistry
Cities*
Environmental Monitoring*
Guideline Adherence / statistics & numerical data*
Hydrocarbons, Halogenated / analysis*
International Cooperation*
Ozone / chemistry
Taiwan

Substances

Air Pollutants
Hydrocarbons, Halogenated
Ozone