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Maps of predicted GSH OP-weighted PM10 levels in OP m–3 in a selected area of central London, U.K. (A) Lowest week (beginning December 6, 2004; values ranged from −3.4 to 29.2 OP m–3); (B) Mean across 2002–2006 (values ranged from 3.0 to 50.4 OP m–3); (C) Highest week (beginning July 21, 2003; values ranged from 22.0 to 88.3 OP m–3).
