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| Titel |
Atmospheric Dust Burden for Last Glacial, Present and Doubled Carbon Dioxide Climate Conditions from CLIMBER-2 Simulations |
| VerfasserIn |
E. Bauer, A. Ganopolski, V. Petoukhov |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250020096
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| Zusammenfassung |
| The atmospheric burden of mineral dust is controlled by processes of dust
emission, transport and deposition. Changes in vegetation cover from natural
or anthropogenic climate change are a key factor for changes in dust emission.
Increases in surface temperature and precipitation imply a decrease of the
land area with no or little vegetation cover and consequently the potential
dust source area diminishes. Other factors controlling the strength of dust
emission are surface wind speed and soil dryness which also depend on climate
conditions. Our goal is to simulate with the CLIMBER-2 Earth system model the
mineral dust cycle dynamically consistent with the climate system and to
investigate the radiative impact of the dust cycle on the climate system. As
an essential step towards this goal we demonstrate that the present-day
distribution of dust optical thickness simulated with the dust cycle agrees
reasonably with GCM simulations and satellite retrievals. Also, the simulated
dust deposition fluxes for the present climate and the Last Glacial Maximum
compare closely with reconstructions from Dust Indicators and Records of
Terrestrial and MArine Palaeoenvironments (DIRTMAP). However, simulations
over glacial cycles suggest that the agreement between simulated and
reconstructed dust deposition fluxes can be improved on orbital time scales by
accounting for the stimulating effect of carbon dioxide on vegetation growth.
The relative importance of this extra factor is shown for the simulated
atmospheric dust burden for last glacial, present and doubled carbon dioxide
climate conditions. These results are comparable with the simulations of the
NCAR Community Climate System model (CCSM3). |
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