DETECTION METHOD FOR FOG AT DAWN

摘要

PURPOSE: A method for detecting fog before and after sunrise is provided to improve the reliability of fog detection without a separate cloud eliminating process. CONSTITUTION: A method for detecting fog before and after sunrise includes the following: times between 5AM to 9AM are set as a sunrise reference time; if visible ray reflectivity of each time in the sunrise reference time is 0 or less, first brightness temperature differences with respect to 37um and 11um of infrared ray at each time are obtained; a first brightness temperature difference replacing process between times is repeated; if visible ray reflectivity of each time in the sunrise reference time is 3 or more, second brightness temperature differences with respect to 37um and 11um of infrared ray at each time are obtained; the second brightness temperature differences are multiplied with the first brightness temperature differences of previous times to obtain third brightness temperature differences; and if the third brightness temperature difference of a specific area is minus, the specific area is set as a fog generating area.