Comparative analysis of spectral characteristics of EO-1 ALI and Landsat 8 OLI imagery

Landsat 8 (L8) is the only normally operating Landsat satellite at present, and the Earth Observing One (EO-1) Advanced Land Imager (ALI) was the prototype for operational land imager (OLI) on-board the L8 satellite. To comprehend well the differences in spectral characteristics between the two sensors, six nearly simultaneous image pairs were selected, which included five land-cover categories: water, bare soil, vegetation, manmade and rock. Moreover, comparisons of spectral characteristics were made through orbital parameters, imaging parameters, spectral response characteristics and spectral characteristics. Finally, the mutual quantitative relations were built up among these image pairs. The results demonstrate that Landsat 8 OLI and EO-1 ALI have similar orbital parameters. With regard to the imaging and spectral response characteristics, the top-of-atmosphere (TOA) reflectance and normalized difference vegetation index (NDVI) of EO-1 ALI are slightly different from those of L8 OLI, but there is a high correlation between EO-1 ALI and L8 OLI of TOA reflectance and NDVI, with the coefficients of determination ranging from 0.962 to 0.994. Therefore, the TOA reflectance and NDVI images from the two sensors are complementary.