Understanding the dust cycle at high latitudes: integrating models and observations
Abstract
Changing climate conditions affect dust emissions and the global dust cycle, which in turn affects climate and biogeochemistry. Paleodust archives from land, ocean, and ice sheets preserve the history of dust deposition for a range of spatial scales from close to the major hemispheric sources to remote sinks such as the polar ice sheets. In each hemisphere common features on the glacial-interglacial time scale mark the baseline evolution of the dust cycle, and inspired the hypothesis that increased dust deposition to ocean stimulated the glacial biological pump contributing to the reduction of atmospheric carbon dioxide levels. On the other hand finer geographical and temporal scales features are superposed to these glacial-interglacial trends, providing the chance of a more sophisticated understanding of the dust cycle, for instance allowing distinctions in terms of source availability or transport patterns as recorded by different records. As such paleodust archives can prove invaluable sources of information, especially when characterized by a quantitative estimation of the mass accumulation rates, and interpreted in connection with climate models. We review our past work and present ongoing research showing how climate models can help in the interpretation of paleodust records, as well as the potential of the same observations for constraining the representation of the global dust cycle embedded in Earth System Models, both in terms of magnitude and physical parameters related to particle sizes and optical properties. Finally we show the impacts on climate, based on this kind of observationally constrained model simulations.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMPP21C1269A
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3344 Paleoclimatology;
- ATMOSPHERIC PROCESSES;
- 4904 Atmospheric transport and circulation;
- PALEOCEANOGRAPHY;
- 4914 Continental climate records;
- PALEOCEANOGRAPHY