What does satellite cloud picture think of the satellite cloud image of the Central Meteorological Observatory?
The satellite image is green. The darker the green, the stronger the ground radiation and the better the weather. When the sky above a certain place is covered with clouds and rain, what the satellite observes is the infrared radiation from the cloud top to space, which is white or grayish white.
white indicates that the ground radiation is very weak, the temperature is very low, the cloud system is thick and dense, and the rainfall intensity is also very high. The transition zone between the clear sky area and the cloudy and rainy area is usually covered by dark gray, gray and light gray clouds, indicating that there are clouds with different thicknesses without obvious precipitation. On the satellite cloud images displayed on TV, the surface and ocean are usually represented by green and blue.
The visible light cloud pictures taken by meteorological satellites from space are taken by using the scattered light generated by the scattering of coarse particles of sunlight by cloud droplets and ice crystals. White on the cloud image indicates strong sunlight reflection, and gray and black places indicate weak reflection.
Because the reflection ability of the land is higher than that of the ocean, the land is gray and the ocean is black on the visible light cloud map, while the areas covered by ice, snow and deep clouds are generally white. Extended data
According to the different instruments and devices on the satellite, satellite cloud pictures can be divided into two categories: one is the cloud pictures taken by the satellite TV camera, that is, TV cloud pictures; The other is the cloud image obtained by scanning and detecting the earth's atmosphere by radiometer. On the TV cloud image, the black and white degree of the image indicates the reflectivity of the ground surface and various clouds to solar radiation, white indicates the strongest reflectivity, and black indicates the weakest reflectivity.
There are two kinds of satellite cloud images detected by scanning radiometer:
① When the radiometer is used to measure the reflected radiation intensity of a certain band (such as .52 ~ .73 micron) of solar radiation visible light from clouds and different ground surfaces, a cloud image similar to a TV cloud image can be obtained due to the different reflection abilities of different clouds and different ground surfaces. This kind of cloud image, together with TV cloud image, is collectively called visible light cloud image.
② measure the infrared radiation emitted from the cloud top or the ground surface in atmospheric window band (8.5 ~ 11 microns) with a radiometer. This observation value can be converted into the radiation temperature of cloud top or ground surface, and the temperature is expressed in black and white levels, thus obtaining a distribution image of cloud and ground surface with different properties. This kind of image is called infrared cloud image.
Baidu Encyclopedia-Satellite Cloud Images