Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/acp-2017-1116
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
28 Feb 2018
Review status
This discussion paper is a preprint. A revision of the manuscript is under review for the journal Atmospheric Chemistry and Physics (ACP).
Implementing Microscopic Charcoal Particles Into a Global Aerosol-Climate Model
Anina Gilgen1, Carole Adolf2,3,*, Sandra O. Brugger2,3,*, Luisa Ickes1,a, Margit Schwikowski4,3,5, Jacqueline F. N. van Leeuwen2,3, Willy Tinner2,3,6, and Ulrike Lohmann1 1ETH Zürich, Institute for Atmospheric and Climate Science, Switzerland
2University of Bern, Institute of Plant Sciences, Switzerland
3University of Bern, Oeschger Centre for Climate Change Research, Switzerland
4Paul Scherrer Institut, Villigen, Switzerland
5University of Bern, Department of Chemistry and Biochemistry, Switzerland
6ETH Zürich, Institute of Terrestrial Ecosystems, Switzerland
anow at: Stockholm University, Department of Meteorology, Sweden
*These co-authors contributed equally to the paper and are considered joint second authors.
Abstract. Microscopic charcoal particles are fire-specific tracers, which are ubiquitous in natural archives such as lake sediments or ice cores. Thus, charcoal records from lake sediments are nowadays the primary source for reconstructing past fire activity. Microscopic charcoal particles are generated during forest and grassland fires and can be transported over large distances before being deposited into natural archives. In this paper, we implement microscopic charcoal particles into a global aerosol-climate model to better understand the transport of charcoal on the large scale. Atmospheric transport as well as interactions with other aerosol particles, clouds, and radiation are explicitly simulated. To estimate the emissions of the microscopic charcoal particles, we use recent European charcoal observations from lake sediments as a calibration dataset. We found that scaling black carbon fire emissions from the Global Fire Assimilation System (a satellite-based emission inventory) by a factor of ≈ 40 matches the calibration dataset best. The charcoal validation dataset, for which we collected charcoal observations from all over the globe, generally supports this scaling factor. In the validation dataset, we included charcoal particles from lake sediments, peats, and ice cores. The correlation coefficients for both the calibration and the validation dataset are positive and significantly different from zero, showing that the model captures a significant portion of the spatial variability. However, the model fails to reproduce the extreme spatial variability observed in the charcoal data. This can mainly be explained by the coarse spatial resolution of the model and uncertainties concerning fire emissions. Furthermore, charcoal fluxes derived from ice core sites are much lower than the simulated fluxes, which can be explained by the location properties (high altitude and steep topography, which are not well represented in the model) of most of the investigated ice cores. Global modelling of charcoal can improve our understanding of the representativeness of this fire proxy. Furthermore, it might allow to quantitatively validate past fire emissions provided by fire models. This might deepen our understanding of the processes driving global fire activity.
Citation: Gilgen, A., Adolf, C., Brugger, S. O., Ickes, L., Schwikowski, M., van Leeuwen, J. F. N., Tinner, W., and Lohmann, U.: Implementing Microscopic Charcoal Particles Into a Global Aerosol-Climate Model, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-1116, in review, 2018.
Anina Gilgen et al.
Anina Gilgen et al.
Anina Gilgen et al.

Viewed

Total article views: 293 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
227 57 9 293 9 4

Views and downloads (calculated since 28 Feb 2018)

Cumulative views and downloads (calculated since 28 Feb 2018)

Viewed (geographical distribution)

Total article views: 293 (including HTML, PDF, and XML)

Thereof 291 with geography defined and 2 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 23 Jun 2018
Publications Copernicus
Download
Short summary
Microscopic charcoal particles are fire-specific tracers, which are presently the primary source for reconstructing past fire activity. In this study, we implement microscopic charcoal particles into a global aerosol-climate model to better understand the transport of charcoal on the large scale. We find that the model captures a significant portion of the spatial variability, but fails to reproduce the extreme variability observed in the charcoal data.
Microscopic charcoal particles are fire-specific tracers, which are presently the primary source...
Share