Gold Level 1D Day Disk Solar Zenith Angles Plots

Level 1D files contain a thumbnail image (PNG) for individual nightside disk scans using the low
resolution slit for Solar Zenith Angle (SZA). Separate files are created for Channel A and Channel B data.
A new L1D file is generated for each new L1C file. These can correspond to either the Northern or Southern
hemisphere. Individual file definitions (image size = 512 x 512 pixels).SZA solar zenith angle map is at
the reference altitude of 150 km.

L1D文件中存储有针对采用低分辨率狭缝开展的各次夜侧圆盘扫描的PNG格式缩略图，该缩略图用于表征太阳天顶角（Solar Zenith Angle, SZA）。通道A与通道B的数据将分别生成独立的L1D文件。每一个新的L1C文件都会对应生成一个新的L1D文件，此类文件可对应北半球或南半球的扫描数据。单份L1D文件的图像尺寸为512×512像素。太阳天顶角（SZA）映射的参考高度为150千米。