Western Water Depth Visible Remote Sensing

Remotely sensed bathymetric technology has a wide application for the water-depth measurement in a coastal zone, an estuary and other water bodies of different types. This paper constructs some water-depth retrieval models of Xiyang water area based on the field data of depth and MODIS image data of spectral reflectance. Owing to the turbid characteristic of Xiyang water affecting the light crossing, suspended sediment concentration remote gene is conceived through the correction of the concentration of vertical suspended sediment and spectral reflectance. This gene introduced to the water-depth retrieval research of visible remote sensing. The research conclusions show as follows.(1) Analysis some statistical correlation models constructed by measured water depth and blue & green spectrums whose attenuation coefficients are the lowest and water depth. Research shows the linear effect is better. Through the independent sample examination, the average relative error of all depth swatches is 34.3% and of the range (5-15m)is 13.4%.(2) Based on calculating the relation coefficient between MODIS reflectance between vertical suspended sediment concentration S and Ln(S), then choose the sensitive band. The single wave band model and combined-wave-band model are constructed, consequently distill suspended sediments remote gene R_s=b14p/b34d= (b1+b4)/(b3/b4), furthermore there is obviously linear correction between R_s and vertical suspended sediments concentration S.(3) Construct the model which introduces the suspended sediment factor; decrease the effects of suspended sediment on water depth; then analysis the model precision. The average relative error of all depth swatches is 24.9% and of the range of 5-15m is 8.9%. The result shows that the model effect which introduces the suspended sediment factor is better than the original one.