Baddock_von Holdt et al JGR ES final submission with figures.pdf (1.73 MB)
Assessing landscape dust emission potential using combined ground‐based measurements and remote sensing data
journal contribution
posted on 2019-04-25, 13:10 authored by J.R.C. von Holdt, F.D. Eckardt, Matthew BaddockMatthew Baddock, Giles F.S. WiggsModeled estimates of aeolian dust emission can vary by an order of magnitude due to the spatiotemporal heterogeneity of emissions. To better constrain location and magnitude of emissions, a surface erodibility factor is typically employed in models. Several landscape-scale schemes representing surface dust-emission potential for use in models have recently been proposed, but validation of such schemes has only been attempted indirectly with medium-resolution remote sensing of mineral aerosol loadings and high-resolution land-surface mapping. In this study, we used dust-emission source points identified in Namibia with Landsat imagery together with field-based dust-emission measurements using a Portable In-situ Wind Erosion Laboratory (PI-SWERL) wind tunnel to assess the performance of schemes aiming to represent erodibility in global dust-cycle modeling. From analyses of the surface and samples taken at the time of wind tunnel testing, a Boosted Regression Tree analysis identified the significant factors controlling erodibility based on PI-SWERL dust flux measurements and various surface characteristics, such as soil moisture, particle size, crusting degree and mineralogy. Despite recent attention to improving the characterisation of surface dust-emission potential, our assessment indicates a high level of variability in the measured fluxes within similar geomorphologic classes. This variability poses challenges to dust modelling attempts based on geomorphology and/or spectral-defined classes. Our approach using high-resolution identification of dust sources to guide ground-based testing of emissivity offers a valuable means to help constrain and validate dust-emission schemes. Detailed determination of the relative strength of factors controlling emission can provide further improvement to regional and global dust-cycle modeling.
Funding
This research was funded by the National Research Foundation in South Africa as part of research project number: UID 89120.
History
School
- Social Sciences
Department
- Geography and Environment
Published in
Journal of Geophysical Research: Earth SurfaceCitation
HOLDT, J.R.C. VON ... et al., 2019. Assessing landscape dust emission potential using combined ground‐based measurements and remote sensing data. Journal of Geophysical Research: Earth Surface, 124 (5), pp.1080-1098.Publisher
© American Geophysical Union (AGU)Version
- AM (Accepted Manuscript)
Publisher statement
An edited version of this paper was published by AGU. Copyright 2019 American Geophysical Union. HOLDT, J.R.C. VON ... et al., 2019. Assessing landscape dust emission potential using combined ground‐based measurements and remote sensing data. Journal of Geophysical Research: Earth Surface, 124 (5), pp.1080-1098. To view the published open abstract, go to https://doi.org/10.1029/2018jf004713Acceptance date
2019-03-30Publication date
2019-04-04Copyright date
2019ISSN
2169-9003eISSN
2169-9011Publisher version
Language
- en