Toward resolution-independent dust emissions in global models: Impacts on the seasonal and spatial distribution of dust

TY - JOUR

T1 - Toward resolution-independent dust emissions in global models

T2 - Impacts on the seasonal and spatial distribution of dust

AU - Ridley, D.A.

AU - Heald, C.L.

AU - Pierce, J.R.

AU - Evans, M.J.

PY - 2013/6/16

Y1 - 2013/6/16

N2 - Simulating the emission of mineral dust and sea-salt aerosol is nonlinear with surface winds and therefore requires accurate representation of surface winds. Consequently, the resolution of a simulation affects emission and is often corrected with nonphysical scaling in coarse resolution global models. We examine the resolution dependence of emissions in the GEOS-Chem model and find that globally, annual emissions at 4° × 5° resolution are 59% of those simulated at 2° × 2.5° and only 33% of emissions at 0.25° × 0.3125°. The spatial and seasonal distribution of dust emissions vary substantially, indicating that applying a uniform scaling is inappropriate. We demonstrate the benefit of characterizing the subgrid surface wind as a Weibull probability distribution, reconciling much of the difference in emissions between resolutions for dust. Such a representation is shown to have little impact on sea-salt emissions.

AB - Simulating the emission of mineral dust and sea-salt aerosol is nonlinear with surface winds and therefore requires accurate representation of surface winds. Consequently, the resolution of a simulation affects emission and is often corrected with nonphysical scaling in coarse resolution global models. We examine the resolution dependence of emissions in the GEOS-Chem model and find that globally, annual emissions at 4° × 5° resolution are 59% of those simulated at 2° × 2.5° and only 33% of emissions at 0.25° × 0.3125°. The spatial and seasonal distribution of dust emissions vary substantially, indicating that applying a uniform scaling is inappropriate. We demonstrate the benefit of characterizing the subgrid surface wind as a Weibull probability distribution, reconciling much of the difference in emissions between resolutions for dust. Such a representation is shown to have little impact on sea-salt emissions.

UR - http://www.scopus.com/inward/record.url?scp=84879931928&partnerID=8YFLogxK

U2 - 10.1002/grl.50409

DO - 10.1002/grl.50409

M3 - Article

AN - SCOPUS:84879931928

SN - 0094-8276

VL - 40

SP - 2873

EP - 2877

JO - Geophysical Research Letters

JF - Geophysical Research Letters

IS - 11

ER -