TY - JOUR
T1 - Mineral dust photochemistry induces nucleation events in the presence of SO2
AU - Dupart, Yoan
AU - King, Stephanie M.
AU - Nekat, Bettina
AU - Nowak, Andreas
AU - Wiedensohler, Alfred
AU - Herrmann, Hartmut
AU - David, Gregory
AU - Thomas, Benjamin
AU - Miffre, Alain
AU - Rairoux, Patrick
AU - D'Anna, Barbara
AU - George, Christian
PY - 2012/12/18
Y1 - 2012/12/18
N2 - Large quantities of mineral dust particles are frequently ejected into the atmosphere through the action of wind. The surface of dust particles acts as a sink for many gases, such as sulfur dioxide. It is well known that under most conditions, sulfur dioxide reacts on dust particle surfaces, leading to the production of sulfate ions. In this report, for specific atmospheric conditions, we provide evidence for an alternate pathway in which a series of reactions under solar UV light produces first gaseous sulfuric acid as an intermediate product before surface-bound sulfate. Metal oxides present in mineral dust act as atmospheric photocatalysts promoting the formation of gaseous OH radicals, which initiate the conversion of SO2 to H2SO4 in the vicinity of dust particles. Under low dust conditions, this process may lead to nucleation events in the atmosphere. The laboratory findings are supported by recent field observations near Beijing, China, and Lyon, France.
AB - Large quantities of mineral dust particles are frequently ejected into the atmosphere through the action of wind. The surface of dust particles acts as a sink for many gases, such as sulfur dioxide. It is well known that under most conditions, sulfur dioxide reacts on dust particle surfaces, leading to the production of sulfate ions. In this report, for specific atmospheric conditions, we provide evidence for an alternate pathway in which a series of reactions under solar UV light produces first gaseous sulfuric acid as an intermediate product before surface-bound sulfate. Metal oxides present in mineral dust act as atmospheric photocatalysts promoting the formation of gaseous OH radicals, which initiate the conversion of SO2 to H2SO4 in the vicinity of dust particles. Under low dust conditions, this process may lead to nucleation events in the atmosphere. The laboratory findings are supported by recent field observations near Beijing, China, and Lyon, France.
KW - Atmospheric optics
KW - LIDAR
KW - OH production
KW - Photocatalysis
KW - SO nucleation
UR - http://www.scopus.com/inward/record.url?scp=84871389632&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871389632&partnerID=8YFLogxK
U2 - 10.1073/pnas.1212297109
DO - 10.1073/pnas.1212297109
M3 - Article
C2 - 23213230
AN - SCOPUS:84871389632
SN - 0027-8424
VL - 109
SP - 20842
EP - 20847
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 51
ER -