Retrieving soil surface roughness with the Hapke photometric model: Confrontation with the ground truth

S. Labarre, S. Jacquemoud, C. Ferrari, A. Delorme, A. Derrien, R. Grandin, M. Jalludin, F. Lemaître, M. Métois, M. Pierrot-Deseilligny, E. Rupnik, B. Tanguy

Remote Sensing of Environment, 225, 1-15 (2019) .

Surface roughness is a key property of soils that controls many surface processes and influences the scattering of incident electromagnetic waves at a wide range of scales. Hapke (2012b) designed a photometric model in which he introduced the effect of surface roughness as a correction factor of the reflectance of a smooth surface. This photometric roughness is defined as the mean slope angle of the facets composing the surface, integrated over all scales from the grain size to the local topography. Yet its physical meaning is still a question at issue, as the scale at which it occurs is not clearly defined. This work aims at better understanding the relative influence of roughness scales on soil BRDF and to test the ability of the Hapke model to retrieve a roughness that depicts effectively the ground truth… Read more