Fast bowtie effect elimination for MODIS L1B data

The bowtie effect refers to geometry distortions for the moderate resolution imaging spectrum-radiometer (MODIS) level 1B (L1B) data. Till now, to eliminate the bowtie effect, numerous methods are proposed. However, most of them have limitations in computation efficiency. Through a comparative study of existing methods, this article puts forward a fast method to eliminate the bowtie effect using the ephemeris data. In this method, the rough positions of overlapping data are first detected. Because of the influence caused by the instrument characters and the earth's curvature, the positions of overlapping data need to be rectified to obtain more precise results. The optimal rectification method used in this article is selected by comparing three methods. By using the optimal method, the rectified MODIS data can be obtained. The experiments demonstrate that the bowtie effect can be eliminated in less than 1 s. In contrast, other traditional methods spend at least 3 s, thus the proposed method is faster and more effective.