Solar geoengineering using solid aerosol in the stratosphere
Solid aerosol particles have long been proposed as an alternative to sulfate aerosols for solar geoengineering. Any solid aerosol introduced into the stratosphere would be subject to coagulation with itself, producing fractal aggregates, and with the natural sulfate aerosol, producing liquid-coated...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2015-10-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | http://www.atmos-chem-phys.net/15/11835/2015/acp-15-11835-2015.pdf |
| _version_ | 1811278414986870784 |
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| author | D. K. Weisenstein D. W. Keith J. A. Dykema |
| author_facet | D. K. Weisenstein D. W. Keith J. A. Dykema |
| author_sort | D. K. Weisenstein |
| collection | DOAJ |
| description | Solid aerosol particles have long been proposed as an alternative to sulfate
aerosols for solar geoengineering. Any solid aerosol introduced into the
stratosphere would be subject to coagulation with itself, producing fractal
aggregates, and with the natural sulfate aerosol, producing liquid-coated
solids. Solid aerosols that are coated with sulfate and/or have formed
aggregates may have very different scattering properties and chemical
behavior than uncoated non-aggregated monomers do. We use a two-dimensional
(2-D) chemistry–transport–aerosol model to capture the dynamics of interacting
solid and liquid aerosols in the stratosphere. As an example, we apply the
model to the possible use of alumina and diamond particles for solar
geoengineering. For 240 nm radius alumina particles, for example, an
injection rate of 4 Tg yr<sup>−1</sup> produces a global-average shortwave
radiative forcing of −1.2 W m<sup>−2</sup> and minimal self-coagulation of alumina
although almost all alumina outside the tropics is coated with sulfate. For
the same radiative forcing, these solid aerosols can produce less ozone
loss, less stratospheric heating, and less forward scattering than
sulfate aerosols do. Our results suggest that appropriately sized alumina,
diamond or similar high-index particles may have less severe
technology-specific risks than sulfate aerosols do. These results,
particularly the ozone response, are subject to large uncertainties due to the
limited data on the rate constants of reactions on the dry surfaces. |
| first_indexed | 2024-04-13T00:34:16Z |
| format | Article |
| id | doaj.art-4a3e4482b57b4e01903e4c7f4707e82d |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-04-13T00:34:16Z |
| publishDate | 2015-10-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-4a3e4482b57b4e01903e4c7f4707e82d2022-12-22T03:10:22ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242015-10-011520118351185910.5194/acp-15-11835-2015Solar geoengineering using solid aerosol in the stratosphereD. K. Weisenstein0D. W. Keith1J. A. Dykema2School of Engineering and Applied Science, Harvard University, Cambridge, MA, USASchool of Engineering and Applied Science, Harvard University, Cambridge, MA, USASchool of Engineering and Applied Science, Harvard University, Cambridge, MA, USASolid aerosol particles have long been proposed as an alternative to sulfate aerosols for solar geoengineering. Any solid aerosol introduced into the stratosphere would be subject to coagulation with itself, producing fractal aggregates, and with the natural sulfate aerosol, producing liquid-coated solids. Solid aerosols that are coated with sulfate and/or have formed aggregates may have very different scattering properties and chemical behavior than uncoated non-aggregated monomers do. We use a two-dimensional (2-D) chemistry–transport–aerosol model to capture the dynamics of interacting solid and liquid aerosols in the stratosphere. As an example, we apply the model to the possible use of alumina and diamond particles for solar geoengineering. For 240 nm radius alumina particles, for example, an injection rate of 4 Tg yr<sup>−1</sup> produces a global-average shortwave radiative forcing of −1.2 W m<sup>−2</sup> and minimal self-coagulation of alumina although almost all alumina outside the tropics is coated with sulfate. For the same radiative forcing, these solid aerosols can produce less ozone loss, less stratospheric heating, and less forward scattering than sulfate aerosols do. Our results suggest that appropriately sized alumina, diamond or similar high-index particles may have less severe technology-specific risks than sulfate aerosols do. These results, particularly the ozone response, are subject to large uncertainties due to the limited data on the rate constants of reactions on the dry surfaces.http://www.atmos-chem-phys.net/15/11835/2015/acp-15-11835-2015.pdf |
| spellingShingle | D. K. Weisenstein D. W. Keith J. A. Dykema Solar geoengineering using solid aerosol in the stratosphere Atmospheric Chemistry and Physics |
| title | Solar geoengineering using solid aerosol in the stratosphere |
| title_full | Solar geoengineering using solid aerosol in the stratosphere |
| title_fullStr | Solar geoengineering using solid aerosol in the stratosphere |
| title_full_unstemmed | Solar geoengineering using solid aerosol in the stratosphere |
| title_short | Solar geoengineering using solid aerosol in the stratosphere |
| title_sort | solar geoengineering using solid aerosol in the stratosphere |
| url | http://www.atmos-chem-phys.net/15/11835/2015/acp-15-11835-2015.pdf |
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