Gaseous and particulate chlorine
species play an important role
in modulating tropospheric oxidation capacity, aerosol water uptake,
visibility degradation, and human health. The lack of recent global
continental chlorine emissions has hindered modeling studies of the
role of chlorine in the atmosphere. Here, we develop a comprehensive
global emission inventory of gaseous HCl and particulate Cl– (pCl), including 35 sources categorized in six source sectors based
on published up-to-date activity data and emission factors. These
emissions are gridded at a spatial resolution of 0.1° ×
0.1° for the years 1960 to 2014. The estimated emissions of HCl
and pCl in 2014 are 2354 (1661–3201) and 2321 (930–3264)
Gg Cl a–1, respectively. Emissions of HCl are mostly
from open waste burning (38%), open biomass burning (19%), energy
(19%), and residential (13%) sectors, and the major sources classified
by fuel type are combustion of waste (43%), biomass (32%), and coal
(25%). Emissions of pCl are mostly from biofuel (29%) and open biomass
burning processes (44%). The sectoral and spatial distributions of
HCl and pCl emissions are very heterogeneous along the study period,
and the temporal trends are mainly driven by the changes in emission
factors, energy intensity, economy, and population.