东距(easting)、北距(northing)、东伪偏移(false easting)、北伪偏移(false northing)

译自:http://wiki.gis.com/wiki/index.php/Easting_and_northing 2020-1-1版

意译,个别地方没有翻译。

东距(easting)、北距(northing)、东伪偏移(false easting)、北伪偏移(false northing)

The terms easting and northing are geographic Cartesian coordinates for a point. Easting refers to the eastward-measured distance (or the x-coordinate), while northing refers to the northward-measured distance (or the y-coordinate). The orthogonal coordinate pair are commonly measured in meters from a horizontal datum. This simple cartographic convention comes from a methodology for determining coordinates and areas, known as the method of latitudes and departures. Eastings are the coordinates that stretch along the bottom x-axis on the map while northings stretch along the side y-axis.

东距和北距用于描述地理笛卡尔坐标系里的任意点的坐标。东距描述X坐标,北距描述Y坐标。这一对直角坐标通常在大地基准面上测量得到,单位是米。(后面的翻译略)
When using the Universal Transverse Mercator coordinate system, northing is the distance to the equator, while easting is the distance to the "false easting", which is uniquely defined in each UTM zone.
在UTM坐标系下,北距是某点到赤道的距离,而东距是该点到其所在的经度带的“东伪偏移”点的距离(后面会解释)。


符号与惯例
Coordinates for locations are provided using two sets of numbers on a simple Cartesian coordinate system. This way, locations can be found using easting/northing (or x,y) pairs. As a convention, the pair is typically represented easting first, northing second.
任意位置的坐标都可以用一对笛卡尔坐标表示。根据惯例,东距在前,北距在后。
For example, the peak of Mount Assiniboine (at 50°52′10″N 115°39′03″W) in UTM Zone 11 is represented by 11U 594934 5636174. Other conventions can also used, such as a truncated grid reference,which would shorten the example coordinates to 949-361.
比如阿悉尼伯因山(北纬50度52分10秒  西经115度39分3秒, 位于UTM的11带)的坐标被表达为 11U 594934 5636174。还有一种更简化的网格表述方式,将上述坐标表达为949-361.

东伪偏移(false easting)
The linear value added to all x-coordinates of a map projection so that none of the values in the geographic region being mapped are negative. The point of origin of each UTM zone is the intersection of the equator and the central meridian of each zone. To avoid dealing with negative numbers the central meridian of each zone is set at 500,000 meters East.
UTM的任何一个经度带的原点都是其中心经线与赤道的交点。假如中心经线的X坐标是零,则中心经线西边的所有点的X坐标都将为负值。为了避免负值出现,设置中心经线的X坐标等于东伪偏移。这个偏移量固定为500,000米。

北伪偏移(false northing)
The linear value added to all y-coordinates of a map projection so that none of the values in the geographic region being mapped are negative. the northing at the equator is set at 10,000,000 meters so no point has a negative value.
同样,为了避免Y坐标出现负值,也可以设置赤道的Y坐标等于北伪偏移--10,000,000米。但由于我国领土位于北半球,因此我国境内的许多遥感数据将北伪偏移设置为0.

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转载自blog.csdn.net/liji_digital/article/details/103790850