Heavy fog identification method and device

The invention provides a heavy fog identification method, which comprises the steps of calculating a solar zenith angle, dividing the whole day into three intervals of daytime, night and morning and evening according to a threshold value, and adaptively matching different heavy fog identification algorithms for initial data to obtain a night pixel, a daytime pixel and a morning and evening pixel; carrying out heavy fog identification processing on the night pixels, the daytime pixels and the morning and night pixels by using a heavy fog identification method to obtain a heavy fog identification result; according to a heavy fog identification result, calculating the pixel identified as heavy fog by using a difference value between long-wave infrared and medium-wave infrared to obtain a water vapor content index; ensuring the connectivity of a heavy fog recognition result through noise removal, misjudgment point or region processing and structure element matrix convolution processing; and combining the finally