(2) Cloud type

The cloud classification data is obtained from the L2 level real-time product of the FY4A satellite. According to the microphysical structure and thermodynamic properties of the cloud, the effective absorption optical thickness ratios of the four visible light channels have different properties. As shown in Table 3, there are 10 categories of cloud type labels included in the image. The sampling moment for cloud classification is the same as that of spectral images, thus forming paired data.

**Table 3.** The description of the cloud type label.

