1. Introduction
[2] Carbonaceous aerosols play an important role in the
Earth’s radiative balance and in climate [IPCC, 2007].
Second only to CO2, in terms of direct climate forcing, black
carbon (BC) is believed to be a principal component of
global warming through absorption of solar radiation since
its warming effect has been found to balance the net cooling
effect of other anthropogenic aerosols [Lindberg et al., 1999;
Jacobson, 2001]. Chung and Seinfeld [2002] estimated BC
global burden is 0.22 Tg with a lifetime of 6.4 d, and predicted
that the globally averaged top of the atmosphere
(TOA) radiative forcing by anthropogenic BC is 0.51–0.8 W
m−2
.