Geodetic CRS: NAD27
Datum: North American Datum 1927
Ellipsoid: Clarke 1866
Prime meridian: Greenwich
Data source: EPSG
Information source: US Coast & Geodetic Survey www.ngs.noaa.gov
Revision date: 2006-12-26
Scope: Geodesy.
Remarks: Uses NADCON method which expects longitudes positive west; EPSG GeogCRS NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east. May be used as transformation to WGS 84 - see NAD27 to WGS 84 (85) (code 15864).
Method: NADCON
Area of use: United States (USA) - Alaska including EEZ.
Description: (0,)
Definition: OGC Well Known Text 2 (2019)
COORDINATEOPERATION["NAD27 to NAD83 (2)", VERSION["NGS-Usa AK"], SOURCECRS[ GEOGCRS["NAD27", DATUM["North American Datum 1927", ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4267]]], TARGETCRS[ GEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4269]]], METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","alaska.las"], PARAMETERFILE["Longitude difference file","alaska.los"], OPERATIONACCURACY[0.5], USAGE[ SCOPE["Geodesy."], AREA["United States (USA) - Alaska including EEZ."], BBOX[47.88,167.65,74.71,-129.99]], ID["EPSG",1243], REMARK["Uses NADCON method which expects longitudes positive west; EPSG GeogCRS NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east. May be used as transformation to WGS 84 - see NAD27 to WGS 84 (85) (code 15864)."]]
Definition: JavaScript (Proj4js)
proj4.defs("EPSG:1243","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=us_noaa_alaska.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1");
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "Transformation", "name": "NAD27 to NAD83 (2)", "source_crs": { "type": "GeographicCRS", "name": "NAD27", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1927", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4267 }, "remarks": "Note: this CRS includes longitudes which are POSITIVE EAST. Replaced by NAD27(76) (code 4608) in Ontario, CGQ77 (code 4609) in Quebec, Mexican Datum of 1993 (code 4483) in Mexico, NAD83 (code 4269) in Canada (excl. Ontario & Quebec) & USA." }, "target_crs": { "type": "GeographicCRS", "name": "NAD83", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1983", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4269 }, "remarks": "Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada." }, "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "alaska.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "alaska.los", "id": { "authority": "EPSG", "code": 8658 } } ], "accuracy": "0.5", "scope": "Geodesy.", "area": "United States (USA) - Alaska including EEZ.", "bbox": { "south_latitude": 47.88, "west_longitude": 167.65, "north_latitude": 74.71, "east_longitude": -129.99 }, "id": { "authority": "EPSG", "code": 1243 }, "remarks": "Uses NADCON method which expects longitudes positive west; EPSG GeogCRS NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east. May be used as transformation to WGS 84 - see NAD27 to WGS 84 (85) (code 15864)." }
Definition: MapServer - MAPfile
PROJECTION "proj=pipeline" "step" "proj=axisswap" "order=2,1" "step" "proj=unitconvert" "xy_in=deg" "xy_out=rad" "step" "proj=hgridshift" "grids=us_noaa_alaska.tif" "step" "proj=unitconvert" "xy_in=rad" "xy_out=deg" "step" "proj=axisswap" "order=2,1" END
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=us_noaa_alaska.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1"> <Layer srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=us_noaa_alaska.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1"> </Layer> </Map>
Definition: SQL (PostGIS)
INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 1243, 'EPSG', 1243, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=us_noaa_alaska.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');