Characterization of dust emission from alluvial sources using aircraft observations and high‐resolution modeling

摘要: [1] We investigate mineral dust emission from alluvial sediments within the upland region in northern Mauritania vicinity of a decaying nocturnal low-level jet (LLJ). For first time, impact valleys that are embedded rather homogeneous surrounding is investigated with regard to their role as source. Measures for local atmospheric burden were retrieved airborne observations, satellite and model simulations analyzed order provide complementary information at different horizontal scales. Observations by LEANDRE Nouvelle Generation backscatter lidar system flying aboard French Falcon 20 aircraft taken along five parallel flight legs perpendicular orientation main valley dominating topography study area. Results comparison lidar-derived extinction coefficients aerial photographs confirm relevance (1) bottoms source, (2) break-down LLJ trigger this region. An evaluation AROME regional model, forecasting high resolution (5 km grid), points toward an under-representation sources This also evident MesoNH research model. Although show higher loadings than AROME, which more comparable both models underestimate concentrations boundary layer compared observations. A sensitivity on grid spacing versus 1 km) highlights importance spatial simulated loadings.