Real time extracting method for satellite remote sensing sea fog characteristic quantity

Abstract

The invention relates to a real-time extracting method of satellite remote sensing sea fog characteristic quantity, daytime EOS / MODIS data is used and is read into a raw data file PDS, the difference of sea fog and low cloud on a spectral characteristic is analyzed in two steps that: firstly, the sea fog and the low cloud are separated, and then, the sea fog characteristic quantity is extracted, namely that a three-level identifying method is adopted to orderly filter high cloud, middle cloud, low cloud, a cloudless water body, a solar flare water body, a cloud shadow area, a sea ice and a snow cover, the sea fog detection is established, a sea fog distributing area is obtained, a file which comprises a sea fog detecting result is generated, then, the sea fog characteristic quantity of the optical thickness of a fog area, the effective radius of fog and a liquid water path are calculated according to a formula, and pictures are displayed on a microcomputer. The method not only extracts the sea fog characteristic quantity, but also can calculate the visibility and the fog top height of the fog, consequently, the quantification detection of the sea fog is realized, and a dissipation forecast of the sea fog supplies meteorological information for air safety above the sea, maritime traffic and coastal airport operation.

Description

technical field [0001] The invention belongs to marine environment monitoring technology, in particular to a method for real-time extraction of satellite remote sensing sea fog feature quantities. Background technique [0002] Sea fog is a common weather phenomenon in my country's coastal waters. When there is sea fog, water vapor condensation produces a large number of fog droplets suspended above the sea surface, and the scattering and reflection of fog droplets reduce the visibility of the sea surface, which has an important impact on human sea activities. [0003] Existing studies have shown that foreign literature reports use channels 1, 3 and 4 of the AVHRR (Very High Resolution Radiometer) of NOAA satellites to invert satellite remote sensing data to obtain fog and low clouds with a certain spatial generality (following Abbreviated as fog / low cloud) feature quantities: fog / low cloud droplet effective radius re, optical thickness τ, liquid water path LWP (Liquidwater ...

AI Technical Summary

Problems solved by technology

However, the existing technology does not separate the fog from the low cloud, and essentially does not invert the characteristic quantity of the sea fog, and the change of the characteristic quantity of the sea fog is related to the generation and disappearance of the sea fog. According to the optical thickness of the sea fog, the effective radius and the liquid water The change of content can provide an important basis for sea fog dissipation forecast

However, if the sea fog is not distinguished from the low cloud, strictly speaking, the feature quantity of the sea fog cannot be extracted, and it is impossible to provide information for the prediction of sea fog dissipation.

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