PROJ-DATUMGRID

NOTE: This repository is only to be used with PROJ < 7. For PROJ 7 or later, use the PROJ-data repository.

The files in this package can be unpacked in the PROJ data directory. For an installed PROJ this may be /usr/local/share/proj or /usr/share/proj on unix style operating systems.

Note that this package includes "CTable2" format grid shift files for NAD27 in the USA and require PROJ 4.8.0 or newer. On the plus side there is no need to compile ascii files into binary files with this version as CTable2 files are not system dependent (as distinct from the CTable files produced in PROJ 4.7.0 and older).

About the Datum Grid package

The datum grid package for PROJ is maintained on the OSGeo proj-datumgrid repository on GitHub. Anyone cloning it, or one of its forks, needs to install the Git Large File Storage (LFS) extension, due to the presence of files larger than 100 MB. Consult the GitHub introduction to LFS for more information.

All grids in the package are released under permissive licenses. New grids are accepted into the package as long as they are released under a license that is compatible with the Open Source Definition and the source of the grid is clearly stated and verifiable. Suitable licenses include:

• Public domain
• X/MIT
• BSD 2/3/4 clause
• CC0
• CC-BY (v3.0 or later)
• CC-BY-SA (v3.0 or later)

Consult CONTRIBUTING.md to submit a new grid.

Horizontal grids

2-dimensional transformation grids for horizontal datum shifts.

Canada: NAD27 -> NAD83

Source: Natural Resources Canada
Format NTv1
License: Public Domain

Grid conversion from NAD27 to NAD83 in Canada. This file is superseded by a higher resolution ntv2_0.gsb grid.

• ntv1_can.dat

France: NTF -> RGF93

Grid transformation from NTF to RGF93 in France.

Source: IGN
Format: NTv2
License: License Ouverte (in French) / Open License (English translation)

• ntf_r93.gsb

Germany: DE_DHDN -> ETRS89

Source: ADV, with direct link from BKG
Format: NTv2
License: Free redistribution is allowed and welcome

Grid transformation from DE_DHDN to ETRS89 in Germany.

• BETA2007.gsb

Note: proj-datumgrid-europe includes the BWTA2017.gsb grid for Baden-Württemberg

New Zealand: NZGD49 -> NZGD2000

Source: LINZ
Format: NTv2
License: Creative Commons Attribution 3.0 New Zealand

This grid file was computed by Land Information New Zealand at approximately a 20 km interval for the conversion between NZGD49 and NZGD2000.

• nzgd2kgrid0005.gsb

USA: NAD27 and older CRS -> NAD83

Source: .los/.las files coming from NOAA
Format: CTable2
License: Public Domain

• alaska - Alaska
• conus - Conterminous U.S.
• hawaii - Hawaii. Old Hawaiian (EPSG:4135) to NAD83
• prvi - Puerto Rico, Virgin Is. Puerto Rico (EPSG:4139) to NAD83
• stgeorge - St. George Is, Alaska. St. George Island (EPSG:4138) to NAD83
• stlrnc - St. Lawrence Is., Alaska. St. Lawrence Island (EPSG:4136) to NAD83
• stpaul - St. Paul Is., Alaska. St. Paul Island (EPSG:4137) to NAD83

USA: NAD83 -> NAD83 (HARN/HPGN)

Source: .los/.las files coming from NOAA
Format: CTable2 License: Public Domain

Grid data for high precision conversion of geographic coordinates from the original NAD83 (1986) (EPSG:4269) to NAD83 High Precision Geodetic Networks (HPGNs) (EPSG:4152), also referred to as High Accuracy Reference Networks (HARNs). NAD 83 coordinates based on the HPGN/HARN surveys changed approximately 0.2 to 1.0 meter relative to the original NAD 83 (1986) adjustment.

• FL - Florida
• MD - Maryland
• TN - Tennessee
• WI - Wisconsin
• WO - Washington, Oregon, N. California

Vertical grids

1-dimensional transformation grids for vertical datum shifts.

Worldwide: EGM96 geoid model

Source: NGA
Format: GTX
License: Public Domain

15 minute worldwide geoid undulation grid that transforms physical heights to WGS84 ellipsoidal heights.

• egm96_15.gtx

Regional PROJ resource packages

In addition to the core proj-datumgrid package, regional collections of grids and init-files also exist. These includes grids and init-files that are not essential for the functionality of PROJ but still of general interest to PROJ-users in the package-specific regions.

The regional packages can be downloaded from the OSGeo download server.

World

This additional package with world scope contains files of big size.

More information about the included grids and init files can be found in README.WORLD

Europe

The regional package for Europe includes resources for the following countries:

• Denmark
• France
• Ireland+Northern Ireland
• Sweden
• The Faroe Islands
• The Nordic+Baltic countries

More information about the included grids and init files can be found in README.EUROPE

North America

The regional package for North America includes resources for the following countries:

• Canada
• Greenland
• USA

More information about the included grids and init files can be found in README.NORTHAMERICA

Oceania

The regional package for Oceania includes resources for the following countries:

• Australia
• New Zealand

More information about the included grids can be found in README.OCEANIA