TY - JOUR
T1 - New insights into the wind-dust relationship in sandblasting and direct aerodynamic entrainment from wind tunnel experiments
AU - Parajuli, Sagar Prasad
AU - Zobeck, Ted M.
AU - Kocurek, Gary
AU - Yang, Zong-Liang
AU - Stenchikov, Georgiy L.
N1 - KAUST Repository Item: Exported on 2020-10-01
PY - 2016/2/18
Y1 - 2016/2/18
N2 - Numerous parameterizations have been developed for predicting wind erosion, yet the physical mechanism of dust emission is not fully understood. Sandblasting is thought to be the primary mechanism, but recent studies suggest that dust emission by direct aerodynamic entrainment can be significant under certain conditions. In this work, using wind tunnel experiments, we investigated some of the lesser understood aspects of dust emission in sandblasting and aerodynamic entrainment for three soil types, namely clay, silty clay loam, and clay loam. First, we explored the role of erodible surface roughness on dust emitted by aerodynamic entrainment. Second, we compared the emitted dust concentration in sandblasting and aerodynamic entrainment under a range of wind friction velocities. Finally, we explored the sensitivity of emitted dust particle size distribution (PSD) to soil type and wind friction velocity in these two processes. The dust concentration in aerodynamic entrainment showed strong positive correlation, no significant correlation, and weak negative correlation, for the clay, silty clay loam, and clay loam, respectively, with the erodible soil surface roughness. The dust in aerodynamic entrainment was significant constituting up to 28.3, 41.4, and 146.4% compared to sandblasting for the clay, silty clay loam, and clay loam, respectively. PSD of emitted dust was sensitive to soil type in both sandblasting and aerodynamic entrainment. PSD was sensitive to the friction velocity in aerodynamic entrainment but not in sandblasting. Our results highlight the need to consider the details of sandblasting and direct aerodynamic entrainment processes in parameterizing dust emission in global/regional climate models.
AB - Numerous parameterizations have been developed for predicting wind erosion, yet the physical mechanism of dust emission is not fully understood. Sandblasting is thought to be the primary mechanism, but recent studies suggest that dust emission by direct aerodynamic entrainment can be significant under certain conditions. In this work, using wind tunnel experiments, we investigated some of the lesser understood aspects of dust emission in sandblasting and aerodynamic entrainment for three soil types, namely clay, silty clay loam, and clay loam. First, we explored the role of erodible surface roughness on dust emitted by aerodynamic entrainment. Second, we compared the emitted dust concentration in sandblasting and aerodynamic entrainment under a range of wind friction velocities. Finally, we explored the sensitivity of emitted dust particle size distribution (PSD) to soil type and wind friction velocity in these two processes. The dust concentration in aerodynamic entrainment showed strong positive correlation, no significant correlation, and weak negative correlation, for the clay, silty clay loam, and clay loam, respectively, with the erodible soil surface roughness. The dust in aerodynamic entrainment was significant constituting up to 28.3, 41.4, and 146.4% compared to sandblasting for the clay, silty clay loam, and clay loam, respectively. PSD of emitted dust was sensitive to soil type in both sandblasting and aerodynamic entrainment. PSD was sensitive to the friction velocity in aerodynamic entrainment but not in sandblasting. Our results highlight the need to consider the details of sandblasting and direct aerodynamic entrainment processes in parameterizing dust emission in global/regional climate models.
UR - http://hdl.handle.net/10754/594985
UR - http://doi.wiley.com/10.1002/2015JD024424
UR - http://www.scopus.com/inward/record.url?scp=84959378539&partnerID=8YFLogxK
U2 - 10.1002/2015JD024424
DO - 10.1002/2015JD024424
M3 - Article
SN - 2169-897X
VL - 121
SP - 1776
EP - 1792
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
IS - 4
ER -