Black carbon emissions in the United Kingdom during the past four decades: an empirical analysis

Abstract

We use data from a unique 40-year recordof 150 urban andrural stations in the ‘‘Black Smoke andSO 2 Network’’ in Great Britain to infer information about sources of atmospheric black carbon (BC). The data show a rapid decline of ambient atmospheric BC between 1962 and the early 1990s that exceeds the decline in official estimates of BC emissions basedonly on amount of fuel use andmostly fixedemission factors. This provid es empirical confirmation of the existence and large impact of a time-dependent ‘‘technology factor’’ that must multiply the rate of fossil fuel use. Current ambient BC amounts in Great Britain comparable to those in western andcentral Europe, with diesel engines being the principal present source. From comparison of BC andSO 2 data we infer that current BC emission inventories understate true emissions in the UK by about a factor of two. The results imply that there is the potential for improved technology to achieve large reduction of global ambient BC. There is a need for comparable monitoring of BC in other countries. r 2004 Elsevier Ltd. All rights reserved.