The files in this section result from the conversion of datasets originating from Geospatial Information Authority of Japan
Source: Geospatial Information Authority of Japan
Format: GeoTIFF converted by GSIGGEO2011.sh
License: CC-BY 4.0.
Horizontal CRS: JDG2011 (EPSG:6667)
Hybrid geoid created by fitting a high-resolution gravimetric geoid model for Japan, “JGEOID2008” to GNSS/leveling geoid undulations at 971 sites by the Least-Squares Collocation method. The standard deviation of the model at the GNSS/leveling sites is 1.8 cm. The geoid height shown in this model is the height over the GRS80-compliant ellipsoid using latitude and longitude values in the Japan Geodetic System 2011 frame.
Note that this grid has a bounding box which is bigger than the declared area of use in its metadata, which is the area of use of JDG2011 (vertical) height. The grid files contains data for the Tokara, Amami, Okinawa, and Sakishima Islands in the Ryukyu Archipelago, the Daitö Islands and the Ogasawara Islands, which all fall out of the area covered by the JDG2011 height (in fact, there isn't any vertical CRS for them in the EPSG catalog).
The number of significant digits of the latitude resolution has been increased compared to the official documentation as it appears to provide better accuracy when results are validated using reference data from https://vldb.gsi.go.jp/sokuchi/surveycalc/geoid/calcgh/calcframe.html For validation, a few points have been hand-picked from arbitrary locations more or less evenly distributed across Japan mainland. The results are in the table below (the CRS is JDG2011):
Lat Lon geoid h (m) reference error (mm)
34.290 135.630 39.860122 39.8601 0.022
36.103 140.087 40.181748 40.1817 0.048
43.217 143.129 30.638869 30.6389 -0.031
38.675 139.886 40.128091 40.1281 -0.009
36.344 137.654 42.895648 42.8956 0.048
33.179 130.063 32.303559 32.3036 -0.041
39.801 141.322 41.886202 41.8862 0.002
The RMS of the error is 0.088 mm.
Derivative work based on gsigeo2011_ver2_1.asc, created with permission:「測量法に基づく国土地理院長承認(使用)R 2JHs 501」
- jp_gsi_gsigeo2011.tif