THE PRECISION OF GOOGLE EARTH MAP ANALYSIS WITH THE COORDINATES OF IGS STATIONS

Abstract. This paper identifies the location of global IGS reference station on Google Earth map, and raises a method of identifying the location and analysis the precise position accuracy. The Google Earth map supports WGS-84 geodetic coordinates. Acquire the WGS-84 Precise Geodetic Coordinates of the Global IGS reference station on IGS Website. The IGS reference station is labeled on the Google Earth map exactly in KML markup language. Using Google Earth ruler tool, calculated the map distance, ground distance and azimuth angle of the Google Earth map position and the labeled position from the precision IGS reference station. Identifying the deviations between the exactly point location of IGS station and the recognized location of Google Earth. About 1,054 IGS stations which covering all over the world are using as samples for data statistics. With a series of statics graph, analysis the accuracy and recognition rate. It shows that the recognition rate is 71.8% and the average accuracy is about 4.38 meters. The accuracy from 2m to 4m occupied 18.76%; the accuracy from 4m to 6m occupied 41.0%; the accuracy from 6m to 8m occupied 6.34%; the accuracy from 8m to 10m occupied 3.70% etc. The accuracy in China region is about 1.5–2 meters and it’s reach up to 1 meter in the cities of the United States, Europe and Japan etc. So that Google Earth map could be used for high-precision positioning services, such as, field reconnaissance, survey network design and the description of station etc.