SAR polarimetry for classification of sea ice: a comparison of physical based algorithms on ICESAR data
Introduction: The observation of sea ice is a major topic in remote sensing due to the difficulty of performing frequent in situ expeditions [1, 2]. Monitoring of sea ice is important for many environmental issues [1]. First of all, it is a sensitive climate indicator and it plays an important role...
| Main Authors: | , , , |
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| Format: | Conference Object |
| Language: | unknown |
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2013
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| Subjects: | |
| Online Access: | https://epic.awi.de/id/eprint/34766/ https://hdl.handle.net/10013/epic.42939 |
| Summary: | Introduction: The observation of sea ice is a major topic in remote sensing due to the difficulty of performing frequent in situ expeditions [1, 2]. Monitoring of sea ice is important for many environmental issues [1]. First of all, it is a sensitive climate indicator and it plays an important role in global climate systems. It restricts the exchange of heat and chemical constituents between ocean and atmosphere acting as an insulator. Moreover, it influences global climate system for effects related with its elevated albedo, reducing the amount of solar radiation absorbed at the Earth’s surface. On the other hand, sea ice affects oceanic circulation directly by the rejection of salt to the underlying ocean during ice growth, that is responsible for deep water formation. Besides these, the possibility and safety of navigation in Polar Regions is severely influenced by the presence of sea ice. SAR: Microwave sensors and Synthetic Aperture Radar (SAR) are very valuable for monitoring of sea ice since they can acquire information in absence of solar illumination (i.e. during Polar nights) and with almost any weather conditions. Unfortunately, the description of the backscattering behaviour of sea ice is particularly challenging. For this reason, many scientists moved toward systems able to increase the amount of information acquired. In this context, polarimetry plays a key role, because it is able to enhance the discrimination capability of the observed target, solving many ambiguities revealed in single polarisation images [3]. Specifically, sea-ice could be modelled as a layered media showing several interfaces: air-snow, snow-ice and (eventually) ice-water [4, 2]. SAR polarimetry: A scattering (Sinclair) matrix [S] can be used to characterise the polarimetric behaviour of deterministic targets [3]. A scattering vector k can be obtained rearranging the elements of the scattering matrix. The Pauli basis was widely exploited to rearrange the scattering matrix in what is defined as the Pauli scattering vector k = ... |
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