UK Hydrographic Office Coastline 1 (HOCL1) - North Atlantic and Mediterranean Sea

Coastline, 50m and 200m depth contour data for the North Atlantic Ocean and Mediterranean sea. Coastline and 200m depth contour principally from 1:3,500,000 (at latitude 22deg 30') Admiralty charts based on the INT series of navigational charts. Correct to 1989, no subsequent updating has been carried out. The 50m depth contour was digitised from larger scale Admiralty and foreign charts. In some areas contours were interpolated from fathoms charts. The data set consists principally of line features defined by about 0.22 million individual geographic locations. In IFF, ASCII character code, this amounts to about 5.8 megabytes. The data conforms to the following conventions: Coastline digitised so that in 95 per cent of instances the error between the digitised and charted coastline is less than 1 mile (0.5mm at chart scale). The area has been divided into 9 sub-areas within which all lines are continuous and digitised so that land/shallow water lies to the right of the line. Small islands have been digitised as single point features. In areas of numerous small islands, only a representative selection has been digitised. Where depth contours appeared very close together on the source charts, the shoalest contour was digitised and then given the feature code of the deeper contour.

本数据集包含了北大西洋和地中海的海岸线以及50米和200米深度等深线数据。海岸线和200米深度等深线数据主要来源于1:3,500,000比例尺（纬度22度30分）的英版海图，该数据基于INT系列航海图系列。数据更新截止至1989年，此后未进行任何后续更新。50米深度等深线数据是通过较大比例尺的英版及外国海图进行数字化处理所得。在某些区域，等深线数据通过英寻海图进行了插值处理。数据集主要由约220万条独立地理位置的线要素构成。在IFF和ASCII字符编码中，这些数据约占5.8兆字节。数据符合以下规范：海岸线数字化后，在95%的情况下，数字化海岸线与海图上海岸线之间的误差小于1英里（在海图比例尺上为0.5毫米）。区域被划分为9个子区域，其中所有线条均连续且数字化，使得陆地/浅水区域位于线条右侧。小岛被数字化为单点要素。在众多小岛区域，仅对具有代表性的部分进行了数字化。在源海图上深度等深线非常靠近的情况下，数字化了最浅的等深线，并赋予了更深等深线的特征代码。