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Indexed by:会议论文

Date of Publication:2012-01-01

Included Journals:CPCI-S、SCIE

Page Number:722-733

Abstract:In polar sea ice observations, digital photography is a powerful tool, which provides solid validations to satellite remote sensing, and also has obvious advantages of lower cost, objectivity, easy operation, and automation as compared with the traditional naked-eye observations. In this study, the techniques were divided into different categories according to the platforms where they installed. For aerial photography providing a nadir view of the ice surface, thresholding methods for gray-scale images can be employed to segment the image into ice and water, segmentation techniques for color images can be applied to partition the image into three categories as ice, water and melt pond, so that ice concentration and floe size can be extracted from the image straightforwardly. For shipboard photography, images in nadir view can provide ice thickness information of broken floes under ship, while images in oblique view will give sea ice conditions in a large area beside the ship: But the geometric distortion induced by oblique photography should be quantitatively estimated before any parameters such as ice concentration and floe size, were extracted from such images. Ice-based oblique photography is similar with shipboard oblique photography, and especially suitable to observe ice surface evolution during a long-term ice station. These techniques have been successfully employed in polar sea ice investigations and even extended to others cold region waters, but further study is still necessary to improve their accuracy and automation.