 |
| Titel |
Sensitivity of cloud condensation nuclei to regional changes in dimethyl-sulphide emissions |
| VerfasserIn |
M. T. Woodhouse, G. W. Mann, K. S. Carslaw, O. Boucher |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 5 ; Nr. 13, no. 5 (2013-03-08), S.2723-2733 |
| Datensatznummer |
250018480
|
| Publikation (Nr.) |
 copernicus.org/acp-13-2723-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| The atmospheric oxidation of dimethyl-sulphide (DMS) derived from
marine phytoplankton is a significant source of marine sulphate
aerosol. DMS has been proposed to regulate climate via changes in
cloud properties, though recent studies have shown that present-day
global cloud condensation nuclei (CCN) concentrations have only a weak
dependence on the total emission flux of DMS. Here, we use a global
aerosol microphysics model to examine how efficiently CCN are produced
when DMS emissions are changed in different marine regions. We find that
global CCN production per unit mass of sulphur emitted varies by more
than a factor of 20 depending on where the change in
oceanic DMS emission flux is applied. The variation in CCN production
efficiency depends upon where CCN production processes (DMS oxidation,
SO2 oxidation, nucleation and growth) are most efficient and
removal processes (deposition) least efficient. The analysis shows
that the production of aerosol sulphate through aqueous-phase
oxidation of SO2 limits the amount of H2SO4 available for
nucleation and condensational growth and therefore suppresses CCN
formation, leading to the weak response of CCN to changes in DMS
emission. Our results show that past and future changes in the spatial
distribution of DMS emissions (through changes in the phytoplankton population or
wind speed patterns) could exert a stronger control on climate than
net increases in biological productivity. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|