摘要
This study is concerned with the need for remote sensing techniques for the monitoring of oil-slick pollution on sea surfaces and the effects of oil-slick pollution on the sea.We used Daqing crude oil,Jilin crude oil,heavy oil and seawater from Dalian Bay to simulate oil-slick pollution on the sea surface and obtained multi-angle hyperspectral polarized reflectance information,from which we calculated the polarization for different kinds of crude oil,and oil-slicks of different thicknesses.By comparing the degree of polarization between oil-slicks of different thickness,and sea water,it was found that in the case of thin oil-slicks,the degree of polarization of seawater is higher than that of oil slicks with wavelengths of between 400-1000 nm.However,there was little difference at a wavelength of 785 nm.At angles of incident of 20° and 30° (the viewing angle equals the incident angle),it was easy to distinguish the changes of oil-slick thickness by the degree of polarization at 785 and 880 nm in the near-infrared band.The crude oil showed its inherent polarized characteristic as the oil-slick thickness increased to a certain degree.That is to say,the polarization of the seawater was higher than that of the oil-slick in the visible light range,but less than that in the near-infrared band.As the incident angle changed from 40° to 50°,the degree of polarization of seawater increased,and it was higher than that for the oil-sick between wavelengths of 400-1000 nm at an angle of incidence of 50°.This research on the polarized characteristics of an oil-slick on a sea surface brings new scientific techniques to the monitoring of sea-surface pollution by remote sensing.
This study is concerned with the need for remote sensing techniques for the monitoring of oil-slick pollution on sea surfaces and the effects of oil-slick pollution on the sea. We used Daqing crude oil, Jilin crude oil, heavy oil and seawater from Dalian Bay to simulate oil-slick pollution on the sea surface and obtained multi-angle hyperspectral polarized reflectance information, from which we calculated the polarization for different kinds of crude oil, and oil-slicks of different thicknesses. By comparing the degree of polarization between oil-slicks of different thickness, and sea water, it was found that in the case of thin oil-slicks, the degree of polarization of seawater is higher than that of oil slicks with wavelengths of between 400-1000 nm. However, there was little difference at a wavelength of 785 nm. At angles of incident of 20~ and 30~ （the viewing angle equals the incident angle）, it was easy to distinguish the changes of oil-slick thickness by the degree of polarization at 785 and 880 nm in the near-infrared band. The crude oil showed its inherent polarized characteristic as the oil-slick thickness increased to a certain degree. That is to say, the polarization of the seawater was higher than that of the oil-slick in the visible light range, but less than that in the near-infrared band. As the incident angle changed from 40°to 50°, the degree of polarization of seawater increased, and it was higher than that for the oil-sick between wavelengths of 400-1000 nm at an angle of incidence of 50°. This research on the polarized characteristics of an oil-slick on a sea surface brings new scientific techniques to the monitoring of sea-surface pollution by remote sensing.
基金
supported by the National Basic Research Program of China (2009CB426305)
National Natural Science Foundation of China (40971190,40771153)
Nurturing Project of Scientific and Technological Innovation Platform,Northeast Normal University (106111065202)
