An optimization algorithm for sea ice density calculation based on idl language

Abstract

The invention relates to an IDL-oriented sea ice concentration calculation optimization algorithm which comprises the steps of reading vertical and horizontal polarization brightness temperature dataand performing preprocessing, and calculating a brightness temperature difference; obtaining a sea ice concentration initial value; performing physical correction; performing de-noising purifying on the sea ice concentration initial value by means of atmosphere filtering; performing expansion processing on land mask layer data by means of a structure, performing mask processing on the sea ice concentration data by means of the expanded land mask, eliminating the sea ice concentration values at the land area and the land edge; eliminating the sea ice concentration values at a satellite blind area next to a pole; eliminating the sea ice concentration values at a low-latitude satellite blind area; and obtaining an accurate sea ice concentration value. According to the algorithm of the invention, steps such as physical correcting, land mask expansion processing and low-latitude satellite blind area filtering are performed; sea ice concentration can be accurately calculated; and defects inan existing sea ice concentration algorithm are prevented.

Description

technical field [0001] The invention relates to an algorithm of how to use IDL programming language to accurately calculate the density of sea ice from radiation brightness temperature data of different frequencies. Background technique [0002] The IDL programming language is flexible, concise, and powerful. Internationally, the IDL language is widely used in marine science, remote sensing, geo-information, and geology. At present, it has not yet reached the level of popularization in my country. The satellite has the characteristics of omnidirectional and multi-temporal, which breaks the regionality of on-site observation and the shortcomings of time asynchrony, and saves a lot of manpower and material resources. Satellite data is more and more recognized by people, and the fields covered by the data will become more and more extensive. AMSR-E Advanced Microwave Scanning Radiometer is a sensor made in Japan and mounted on the NASA (National Aeronautics and Space Administr...

AI Technical Summary

Problems solved by technology

Continental boundaries will produce boundary effects in satellite observations, resulting in strong errors. Therefore, the reliability of the sea ice density values ​​​​in a certain area where the continental boundaries extend to the sea is low, and it needs to be deleted.

Therefore, it is more complicated to accurately calculate the sea ice density

Currently, the most widely used calculation algorithm for sea ice density actually has certain limitations. For the algorithm, see figure 1 ; Because the sea ice density calculated by this algorithm is greater than 1, and the land edge effect is not considered, and there is no treatment method for the regional sea ice density in the low-latitude satellite blind area

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