Automatic detection of ship tracks in ATSR-2 satellite imagery
Automatic detection of ship tracks in ATSR-2 satellite imagery
复制标题
自动检测 ATSR-2 卫星图像中的船舶轨迹
DOI：
10.5194/acp-9-1899-2009
复制
发表时间：
2009
影响因子：
6.3
通讯作者：
A. Sayer
中科院分区：
文献类型：
--
作者：
E. Campmany;R. Grainger;S. Dean;A. Sayer
抽象的。船舶通过向发展中或现有的云添加云凝结核（CCN）来修改云的微观物理学。这些在卫星图像中观察到的云场中产生了较大的反射率线。针对沿着航迹扫描辐射计2（ATSR-2）图像中船舶航迹的自动检测问题，提出了一种算法。该方案已被集成到全球检索ATSR云参数和评估（GRAPE）处理链。该算法首先确定强度脊波云有可能是一个船舶轨迹的一部分。通过将每个像素与其周围的像素进行比较来完成这种识别。如果三个相邻像素的强度大于其相邻像素的强度，则将其分类为脊波。这些脊然后连接在一起，根据一组连通性规则，形成轨道，如果它们足够长，则被归类为船舶轨道。该算法已被应用到两年的ATSR-2数据。船迹最常出现在加州西海岸，以及西非和西南欧的大西洋海岸。船舶航迹的全球分布具有很强的季节性，年际变化较小，与船舶排放的空间分布模式相似。
Abstract. Ships modify cloud microphysics by adding cloud condensation nuclei (CCN) to a developing or existing cloud. These create lines of larger reflectance in cloud fields that are observed in satellite imagery. An algorithm has been developed to automate the detection of ship tracks in Along Track Scanning Radiometer 2 (ATSR-2) imagery. The scheme has been integrated into the Global Retrieval of ATSR Cloud Parameters and Evaluation (GRAPE) processing chain. The algorithm firstly identifies intensity ridgelets in clouds which have the potential to be part of a ship track. This identification is done by comparing each pixel with its surrounding ones. If the intensity of three adjacent pixels is greater than the intensity of their neighbours, then it is classified as a ridgelet. These ridgelets are then connected together, according to a set of connectivity rules, to form tracks which are classed as ship tracks if they are long enough. The algorithm has been applied to two years of ATSR-2 data. Ship tracks are most frequently seen off the west coast of California, and the Atlantic coast of both West Africa and South-Western Europe. The global distribution of ship tracks shows strong seasonality, little inter-annual variability and a similar spatial pattern to the distribution of ship emissions.