Modeling the adjacency effects in Earth observation data with different viewing geometry over mountainous area

For an earth observation system, an increase in the off-nadir viewing angle leads to an increase in line of sight scattered radiance. Meanwhile, steep terrain over mountainous area induces changes in irradiance at ground level and then affects the top of atmosphere (TOA) signal. In this paper, a methodology is presented to simulate and analyze the adjacency effects. In the second section of the paper, the radiative transfer equations are built separately for the nadir viewing geometry and the off-nadir viewing geometry over mountainous area. In order to model the adjacency effects, the radiance items related to the adjacency effects are estimated. During the procedure, the molecular/aerosol scattering phase functions, different viewing geometry, ground heterogeneity and topography are taken into account. The performance of this methodology is validated through simulating a set of space-borne data over mountainous areas for nadir viewing angles and off-nadir viewing angles. The results indicate that the contributions of adjacency effect at TOA are significantly different for the varying viewing geometry conditions. The proposed method proved to be useful in understanding the mechanisms of adjacency effects and it will be applied to atmospheric correction of remotely sensed data.

[1]  Didier Tanré,et al.  Second Simulation of the Satellite Signal in the Solar Spectrum, 6S: an overview , 1997, IEEE Trans. Geosci. Remote. Sens..

[2]  Daniel Schlapfer,et al.  Geo-atmospheric processing of wide-FOV airborne imaging spectrometry data , 2002, Remote Sensing.

[3]  J. Dozier,et al.  Rapid calculation of terrain parameters for radiation modeling from digital elevation data , 1990 .

[4]  John R. Schott,et al.  Remote Sensing: The Image Chain Approach , 1996 .

[5]  Hermann Kaufmann,et al.  On the application of the MODTRAN4 atmospheric radiative transfer code to optical remote sensing , 2009 .

[6]  Gail P. Anderson,et al.  MODTRAN4 radiative transfer modeling for atmospheric correction , 1999, Optics & Photonics.

[7]  W. Verhoef,et al.  Simulation of hyperspectral and directional radiance images using coupled biophysical and atmospheric radiative transfer models , 2003 .

[8]  Cheng Jiang,et al.  Simulation of hyperspectral radiance images with quantification of adjacency effects over rugged scenes , 2013 .

[9]  Xavier Briottet,et al.  Direct and inverse radiative transfer solutions for visible and near-infrared hyperspectral imagery , 2005, IEEE Transactions on Geoscience and Remote Sensing.

[10]  C. Bohren,et al.  An introduction to atmospheric radiation , 1981 .

[11]  Laurent Poutier,et al.  Irradiance calculation over mountainous areas in the reflective spectral domain: comparison with an accurate radiative transfer code , 2003, SPIE Optics + Photonics.