| |
Record |
Links |
|
Author |
Domine Florent, Gallet Jean-Charles, Barret Manuel, Houdier Stphan, Voisin Didier, Douglas Thomas A, Blum Joel D, Beine Harry J, Anastasio Cort, Bron Franois-Marie, |
|
| |
Title |
The specific surface area and chemical composition of diamond dust near Barrow, Alaska
|
Type |
Journal Article |
| |
Year  |
2011 |
Publication |
J. Geophys. Res. |
Abbreviated Journal |
|
|
| |
Volume |
116 |
Issue |
|
Pages |
D00R06- |
|
| |
Keywords |
absorption spectra, aldehydes, dissolved organic carbon, ionic composition, mercury, specific surface area, 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801, 4906), 0317 Atmospheric Composition and Structure: Chemical kinetic and photochemical properties, 0330 Atmospheric Composition and Structure: Geochemical cycles (1030), 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry, 0736 Cryosphere: Snow (1827, 1863), |
|
| |
Abstract |
Diamond dust (DD) refers to tiny ice crystals that form frequently in the Polar troposphere under clear sky conditions. They provide surfaces for chemical reactions and scatter light. We have measured the specific surface area (SSA) of DD at Barrow in March–April 2009. We have also measured its chemical composition in mineral and organic ions, dissolved organic carbon (DOC), aldehydes, H2O2, and the absorption spectra of water-soluble chromophores. Mercury concentrations were also measured in spring 2006, when conditions were similar. The SSA of DD ranges from 79.9 to 223 m2 kg-1. The calculated ice surface area in the atmosphere reaches 11000 (70%) μm2 cm-3, much higher than the aerosol surface area. However, the impact of DD on the downwelling and upwelling light fluxes in the UV and visible is negligible. The composition of DD is markedly different from that of snow on the surface. Its concentrations in mineral ions are much lower, and its overall composition is acidic. Its concentrations in aldehydes, DOC, H2O2 and mercury are much higher than in surface snows. Our interpretation is that DOC from the oceanic surface microlayer, coming from open leads in the ice off of Barrow, is taken up by DD. Active chemistry in the atmosphere takes place on DD crystal surfaces, explaining its high concentrations in aldehydes and mercury. After deposition, active photochemistry modifies DD composition, as seen from the modifications in its absorption spectra and aldehyde and H2O2 content. This probably leads to the emissions of reactive species to the atmosphere.
|
|
| |
Programme |
1017 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
AGU |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0148-0227 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
1623 |
|
| Permanent link to this record |
