Section 4 : Spatial Reference Information Element: Spatial Reference Information Section: 4 Description: the description of the reference frame for, and the means to encode, coordinates in the data set. Element: Horizontal Coordinate System Definition Section: 4.1 Description: the reference frame or system from which linear or angular quantities are measured and assigned to the position that a point occupies. Element: Geographic Section: 4.1.1 Description: the quantities of latitude and longitude which define the position of a point on the Earth's surface with respect to a reference spheroid. Element: Latitude Resolution Section: 4.1.1.1 Description: the minimum difference between two adjacent latitude values expressed in Geographic Coordinate Units of measure. Type: real Domain: Latitude Resolution > 0.0 Element: Longitude Resolution Section: 4.1.1.2 Description: the minimum difference between two adjacent longitude values expressed in Geographic Coordinate Units of measure. Type: real Domain: Longitude Resolution > 0.0 Element: Geographic Coordinate Units Section: 4.1.1.3 Description: units of measure used for the latitude and longitude values. Type: text Domain: "Decimal degrees" "Decimal minutes" "Decimal seconds" "Degrees and decimal minutes" "Degrees, minutes, and decimal seconds" "Radians" "Grads" Element: Planar Section: 4.1.2 Description: the quantities of distances, or distances and angles, which define the position of a point on a reference plane to which the surface of the Earth has been projected. Element: Map Projection Section: 4.1.2.1 Description: the systematic representation of all or part of the surface of the Earth on a plane or developable surface. Must use Albers_Conical_Equal_Area (albers) if Map_Projection_Name (mapprojn) is "Albers Conical Equal Area". Must use Azimuthal_Equidistant (azimequi) if Map_Projection_Name (mapprojn) is "Azimuthal Equidistant". Must use Equidistant_Conic (equicon) if Map_Projection_Name (mapprojn) is "Equidistant Conic". Must use Equirectangular (equirect) if Map_Projection_Name (mapprojn) is "Equirectangular". Must use General_Vertical_Near-sided_Perspective (gvnsp) if Map_Projection_Name (mapprojn) is "General Vertical Near-sided Perspective". Must use Gnomonic (gnomonic) if Map_Projection_Name (mapprojn) is "Gnomonic". Must use Lambert_Azimuthal_Equal_Area (lamberta) if Map_Projection_Name (mapprojn) is "Lambert Azimuthal Equal Area". Must use Lambert_Conformal_Conic (lambertc) if Map_Projection_Name (mapprojn) is "Lambert Conformal Conic". Must use Mercator (mercator) if Map_Projection_Name (mapprojn) is "Mercator". Must use Modified_Stereographic_for_Alaska (modsak) if Map_Projection_Name (mapprojn) is "Modified Stereographic for Alaska". Must use Miller_Cylindrical (miller) if Map_Projection_Name (mapprojn) is "Miller Cylindrical". Must use Oblique_Mercator (obqmerc) if Map_Projection_Name (mapprojn) is "Oblique Mercator". Must use Orthographic (orthogr) if Map_Projection_Name (mapprojn) is "Orthographic". Must use Polar_Stereographic (polarst) if Map_Projection_Name (mapprojn) is "Polar Stereographic". Must use Polyconic (polycon) if Map_Projection_Name (mapprojn) is "Polyconic". Must use Robinson (robinson) if Map_Projection_Name (mapprojn) is "Robinson". Must use Sinusoidal (sinusoid) if Map_Projection_Name (mapprojn) is "Sinusoidal". Must use Space_Oblique_Mercator_(Landsat) (spaceobq) if Map_Projection_Name (mapprojn) is "Space Oblique Mercator (Landsat)". Must use Stereographic (stereo) if Map_Projection_Name (mapprojn) is "Stereographic". Must use Transverse_Mercator (transmer) if Map_Projection_Name (mapprojn) is "Transverse Mercator". Must use van_der_Grinten (vdgrin) if Map_Projection_Name (mapprojn) is "van der Grinten". Must use Map_Projection_Parameters (mapprojp) if Map_Projection_Name (mapprojn) is not one of the 21 enumerated projection names. Element: Map Projection Name Section: 4.1.2.1.1 Description: name of the map projection. Type: text Domain: "Albers Conical Equal Area" "Azimuthal Equidistant" "Equidistant Conic" "Equirectangular" "General Vertical Near-sided Projection" "Gnomonic" "Lambert Azimuthal Equal Area" "Lambert Conformal Conic" "Mercator" "Modified Stereographic for Alaska" "Miller Cylindrical" "Oblique Mercator" "Orthographic" "Polar Stereographic" "Polyconic" "Robinson" "Sinusoidal" "Space Oblique Mercator" "Stereographic" "Transverse Mercator" "van der Grinten" free text Enumerated values also match "free text" ]]> Element: Albers Conical Equal Area Section: 4.1.2.1.2 Description: contains parameters for the Albers Conical Equal Area projection. Element: Azimuthal Equidistant Section: 4.1.2.1.3 Description: contains parameters for the Azimuthal Equidistant projection. Element: Equidistant Conic Section: 4.1.2.1.4 Description: contains parameters for the Equidistant Conic projection. Element: Equirectangular Section: 4.1.2.1.5 Description: contains parameters for the Equirectangular projection. Element: General Vertical Near-sided Perspective Section: 4.1.2.1.6 Description: contains parameters for the General Vertical Near-sided Perspective projection. Element: Gnomonic Section: 4.1.2.1.7 Description: contains parameters for the Gnomonic projection. Element: Lambert Azimuthal Equal Area Section: 4.1.2.1.8 Description: contains parameters for the Lambert Azimuthal Equal Area projection. Element: Lambert Conformal Conic Section: 4.1.2.1.9 Description: contains parameters for the Lambert Conformal Conic projection. Element: Mercator Section: 4.1.2.1.10 Description: contains parameters for the Mercator projection Element: Modified Stereographic for Alaska Section: 4.1.2.1.11 Description: contains parameters for the Modified Stereographic for Alaska projection. Element: Miller Cylindrical Section: 4.1.2.1.12 Description: contains parameters for the Miller Cylindrical projection. Element: Oblique Mercator Section: 4.1.2.1.13 Description: contains parameters for the Oblique Mercator projection. Element: Orthographic Section: 4.1.2.1.14 Description: contains parameters for the Orthographic projection. Element: Polar Stereographic Section: 4.1.2.1.15 Description: contains parameters for the Polar Stereographic projection. Element: Polyconic Section: 4.1.2.1.16 Description: contains parameters for the Polyconic projection. Element: Robinson Section: 4.1.2.1.17 Description: contains parameters for the Robinson projection. Element: Sinusoidal Section: 4.1.2.1.18 Description: contains parameters for the Sinusoidal projection. Element: Space Oblique Mercator (Landsat) Section: 4.1.2.1.19 Description: contains parameters for the Space Oblique Mercator (Landsat) projection. Element: Stereographic Section: 4.1.2.1.20 Description: contains parameters for the Stereographic projection. Element: Transverse Mercator Section: 4.1.2.1.21 Description: contains parameters for theTransverse mercator projection. Element: van der Grinten Section: 4.1.2.1.22 Description: contains parameters for the van der Grinten projection. Element: Map Projection Parameters Section: 4.1.2.1.23 Description: a complete parameter set of the projection that was used for the data set. The information provided shall include the names of the parameters and values used for the data set that describe the mathematical relationship between the Earth and the plane or developable surface for the projection. Element: Standard Parallel Section: 4.1.2.1.23.1 Description: line of constant latitude at which the surface of the Earth and the plane or developable surface intersect. Type: real Domain: -90.0 <= Standard Parallel <= 90.0 Element: Longitude of Central Meridian Section: 4.1.2.1.23.2 Description: the line of longitude at the center of a map projection generally used as the basis for constructing the projection. Type: real Domain: -180.0 <= Longitude of Central Meridian < 180.0 Element: Latitude of Projection Origin Section: 4.1.2.1.23.3 Description: latitude chosen as the origin of rectangular coordinates for a map projection. Type: real Domain: -90.0 <= Latitude of Projection Origin <= 90.0 Element: False Easting Section: 4.1.2.1.23.4 Description: the value added to all "x" values in the rectangular coordinates for a map projection. This value frequently is assigned to eliminate negative numbers. Expressed in the unit of measure identified in Planar Coordinate Units. Type: real Domain: free real Element: False Northing Section: 4.1.2.1.23.5 Description: the value added to all "y" values in the rectangular coordinates for a map projection. This value frequently is assigned to eliminate negative numbers. Expressed in the unit of measure identified in Planar Coordinate Units. Type: real Domain: free real Element: Scale Factor at Equator Section: 4.1.2.1.23.6 Description: a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the equator. Type: real Domain: Scale Factor at Equator > 0.0 Element: Height of Perspective Point Above Surface Section: 4.1.2.1.23.7 Description: height of viewpoint above the Earth, expressed in meters. Type: real Domain: Height of Perspective Point Above Surface > 0.0 Element: Longitude of Projection Center Section: 4.1.2.1.23.8 Description: longitude of the point of projection for azimuthal projections. Type: real Domain: -180.0 <= Longitude of Projection Center < 180.0 Element: Latitude of Projection Center Section: 4.1.2.1.23.9 Description: latitude of the point of projection for azimuthal projections. Type: real Domain: -90.0 <= Latitude of Projection Center <= 90.0 Element: Scale Factor at Center Line Section: 4.1.2.1.23.10 Description: a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the center line. Type: real Domain: Scale Factor at Center Line > 0.0 Element: Oblique Line Azimuth Section: 4.1.2.1.23.11 Description: method used to describe the line along which an oblique mercator map projection is centered using the map projection origin and an azimuth. Element: Azimuthal Angle Section: 4.1.2.1.23.11.1 Description: angle measured clockwise from north, and expressed in degrees. Type: real Domain: 0.0 <= Azimuthal Angle < 360.0 Element: Azimuth Measure Point Longitude Section: 4.1.2.1.23.11.2 Description: longitude of the map projection origin. Type: real Domain: -180.0 <= Azimuth Measure Point Longitude < 180.0 Element: Oblique Line Point Section: 4.1.2.1.23.12 Description: method used to describe the line along which an oblique mercator map projection is centered using two points near the limits of the mapped region that define the center line. Element: Oblique Line Latitude Section: 4.1.2.1.23.12.1 Description: latitude of a point defining the oblique line. Type: real Domain: -90.0 <= Oblique Line Latitude <= 90.0 Element: Oblique Line Longitude Section: 4.1.2.1.23.12.2 Description: longitude of a point defining the oblique line. Type: real Domain: -180.0 <= Oblique Line Longitude < 180.0 Element: Straight Vertical Longitude from Pole Section: 4.1.2.1.23.13 Description: longitude to be oriented straight up from the North or South Pole. Type: real Domain: -180.0 <= Straight Vertical Longitude from Pole < 180.0 Element: Scale Factor at Projection Origin Section: 4.1.2.1.23.14 Description: a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance at the projection origin. Type: real Domain: Scale Factor at Projection Origin > 0.0 Element: Landsat Number Section: 4.1.2.1.23.15 Description: number of the Landsat satellite. (Note: This data element exists solely to provide a parameter needed to define the space oblique mercator projection. It is not used to identify data originating from a remote sensing vehicle.) Type: Integer Domain: free integer Element: Path Number Section: 4.1.2.1.23.16 Description: number of the orbit of the Landsat satellite. (Note: This data element exists solely to provide a parameter needed to define the space oblique mercator projection. It is not used to identify data originating from a remote sensing vehicle.) Path_Number (pathnum) must be less than 251 for Landsats (landsat) 1, 2, or 3. Path_Number (pathnum) must be less than 233 for Landsats (landsat) 4 or 5. Type: integer Domain: 0 < Path Number < 251 for Landsats 1, 2, or 3; 0 < Path Number < 233 for Landsats 4 or 5; free integer Element: Scale Factor at Central Meridian Section: 4.1.2.1.23.17 Description: a multiplier for reducing a distance obtained from a map by computation or scaling to the actual distance along the central meridian. Type: real Domain: Scale Factor at Central Meridian > 0.0 Element: Other Projection's Definition Section: 4.1.2.1.23.18 Description: a description of a projection, not defined elsewhere in the standard, that was used for the data set. The information provided shall include the name of the projection, names of parameters and values used for the data set, and the citation of the specification for the algorithms that describe the mathematical relationship between Earth and plane or developable surface for the projection. Type: text Domain: free text Element: Grid Coordinate System Section: 4.1.2.2 Description: a plane-rectangular coordinate system usually based on, and mathematically adjusted to, a map projection so that geographic positions can be readily transformed to and from plane coordinates. Must use Universal_Transverse_Mercator_(UTM) (utm) if Grid_Coordinate_System_Name (gridsysn) is "Universal Transverse Mercator". Must use Universal_Polar_Stereographic_(UPS) (ups) if Grid_Coordinate_System_Name (gridsysn) is "Universal Polar Stereographic". Must use State_Plane_Coordinate_System_(SPCS) (spcs) if Grid_Coordinate_System_Name (gridsysn) is "State Plane Coordinate System 1927". Must use State_Plane_Coordinate_System_(SPCS) (spcs) if Grid_Coordinate_System_Name (gridsysn) is "State Plane Coordinate System 1983". Must use ARC_Coordinate_System (arcsys) if Grid_Coordinate_System_Name (gridsysn) is "ARC Coordinate System". Must use Other_Grid_System's_Definition (othergrd) if Grid_Coordinate_System_Name (gridsysn) is "other grid system". Element: Grid Coordinate System Name Section: 4.1.2.2.1 Description: name of the grid coordinate system. Type: text Domain: "Universal Transverse Mercator" "Universal Polar Stereographic" "State Plane Coordinate System 1927" "State Plane Coordinate System 1983" "ARC Coordinate System" "other grid system" Element: Universal Transverse Mercator (UTM) Section: 4.1.2.2.2 Description: a grid system based on the transverse mercator projection, applied between latitudes 84 degrees north and 80 degrees south on the Earth's surface. Element: UTM Zone Number Section: 4.1.2.2.2.1 Description: identifier for the UTM zone. Type: integer Domain: 1 <= UTM Zone Number <= 60 for the northern hemisphere; -60 <= UTM Zone Number <= -1 for the southern hemisphere Element: Universal Polar Stereographic (UPS) Section: 4.1.2.2.3 Description: a grid system based on the polar stereographic projection, applied to the Earth's polar regions north of 84 degrees north and south of 80 degrees south. Element: UPS Zone Identifier Section: 4.1.2.2.3.1 Description: identifier for the UPS zone. Type: text Domain: "A" "B" "Y" "Z" Element: State Plane Coordinate System (SPCS) Section: 4.1.2.2.4 Description: a plane-rectangular coordinate system established for each state in the United States by the National Geodetic Survey. Element: SPCS Zone Identifier Section: 4.1.2.2.4.1 Description: identifier for the SPCS zone. Type: text Domain: Four-digit numeric codes for the State Plane Coordinate Systems based on the North American Datum of 1927 are found in Department of Commerce, 1986, Representation of geographic point locations for information interchange (Federal Information Processing Standard 70-1): Washington: Department of Commerce, National Institute of Standards and Technology. Codes for the State Plane Coordinate Systems based on the North American Datum of 1983 are found in Department of Commerce, 1989 (January), State Plane Coordinate System of 1983 (National Oceanic and Atmospheric Administration Manual NOS NGS 5): Silver Spring, Maryland, National Oceanic and Atmospheric Administration, National Ocean Service, Coast and Geodetic Survey. Element: ARC Coordinate System Section: 4.1.2.2.5 Description: the Equal Arc-second Coordinate System, a plane- rectangular coordinate system established in Department of Defense, 1990, Military specification ARC Digitized Raster Graphics (ADRG) (MIL-A-89007): Philadelphia, Department of Defense, Defense Printing Service Detachment Office. Element: ARC System Zone Identifier Section: 4.1.2.2.5.1 Description: identifier for the ARC Coordinate System Zone. Type: integer Domain: 1 <= ARC System Zone Identifier <= 18 Element: Other Grid System's Definition Section: 4.1.2.2.6 Description: a complete description of a grid system, not defined elsewhere in this standard, that was used for the data set. The information provided shall include the name of the grid system, the names of the parameters and values used for the data set, and the citation of the specification for the algorithms that describe the mathematical relationship between the Earth and the coordinates of the grid system. Type: text Domain: free text Element: Local Planar Section: 4.1.2.3 Description: any right-handed planar coordinate system of which the z-axis coincides with a plumb line through the origin that locally is aligned with the surface of the Earth. Element: Local Planar Description Section: 4.1.2.3.1 Description: a description of the local planar system. Type: text Domain: free text Element: Local Planar Georeference Information Section: 4.1.2.3.2 Description: a description of the information provided to register the local planar system to the Earth (e.g. control points, satellite ephemeral data, inertial navigation data). Type: text Domain: free text Element: Planar Coordinate Information Section: 4.1.2.4 Description: information about the coordinate system developed on the planar surface. Must use Coordinate_Representation (coordrep) if Planar_Coordinate_Encoding_Method (plance) is "coordinate pair". Must use Distance_and_Bearing_Representation (distbrep) if Planar_Coordinate_Encoding_Method (plance) is "distance and bearing". Must use Coordinate_Representation (coordrep) if Planar_Coordinate_Encoding_Method (plance) is "row and column". Element: Planar Coordinate Encoding Method Section: 4.1.2.4.1 Description: the means used to represent horizontal positions. Type: text Domain: "coordinate pair" "distance and bearing" "row and column" Element: Coordinate Representation Section: 4.1.2.4.2 Description: the method of encoding the position of a point by measuring its distance from perpendicular reference axes (the "coordinate pair" and "row and column" methods). Element: Abscissa Resolution Section: 4.1.2.4.2.1 Description: the (nominal) minimum distance between the "x" or column values of two adjacent points, expressed in Planar Distance Units of measure. Type: real Domain: Abscissa Resolution > 0.0 Element: Ordinate Resolution Section: 4.1.2.4.2.2 Description: the (nominal) minimum distance between the "y" or row values of two adjacent points, expressed in Planar Distance Units of measure. Type: real Domain: Ordinate Resolution > 0.0 Element: Distance and Bearing Representation Section: 4.1.2.4.3 Description: a method of encoding the position of a point by measuring its distance and direction (azimuth angle) from another point. Element: Distance Resolution Section: 4.1.2.4.3.1 Description: the minimum distance measurable between two points, expressed Planar Distance Units of measure. Type: real Domain: Distance Resolution > 0.0 Element: Bearing Resolution Section: 4.1.2.4.3.2 Description: the minimum angle measurable between two points, expressed in Bearing Units of measure. Type: real Domain: Bearing Resolution > 0.0 Element: Bearing Units Section: 4.1.2.4.3.3 Description: units of measure used for angles. Type: text Domain: "Decimal degrees" "Decimal minutes" "Decimal seconds" "Degrees and decimal minutes" "Degrees, minutes, and decimal seconds" "Radians" "Grads" Element: Bearing Reference Direction Section: 4.1.2.4.3.4 Description: direction from which the bearing is measured. Type: text Domain: "North" "South" Element: Bearing Reference Meridian Section: 4.1.2.4.3.5 Description: axis from which the bearing is measured. Type: text Domain: "Assumed" "Grid" "Magnetic" "Astronomic" "Geodetic" Element: Planar Distance Units Section: 4.1.2.4.4 Description: units of measure used for distances. Type: text Domain: "meters" "international feet" "survey feet" free text Enumerated values also match "free text" ]]> Element: Local Section: 4.1.3 Description: a description of any coordinate system that is not aligned with the surface of the Earth. Element: Local Description Section: 4.1.3.1 Description: a description of the coordinate system and its orientation to the surface of the Earth. Type: text Domain: free text Element: Local Georeference Information Section: 4.1.3.2 Description: a description of the information provided to register the local system to the Earth (e.g. control points, satellite ephemeral data, inertial navigation data). Type: text Domain: free text Element: Geodetic Model Section: 4.1.4 Description: parameters for the shape of the earth. Element: Horizontal Datum Name Section: 4.1.4.1 Description: the identification given to the reference system used for defining the coordinates of points. Ellipsoid_Name (ellips) must be "Clarke 1866" if Horizontal_Datum_Name (horizdn) is "North American Datum of 1927". Ellipsoid_Name (ellips) must be "Geodetic Reference System 80" if Horizontal_Datum_Name (horizdn) is "North American Datum of 1983". Type: text Domain: "North American Datum of 1927" "North American Datum of 1983" free text Enumerated values also match "free text" ]]> Element: Ellipsoid Name Section: 4.1.4.2 Description: identification given to established representations of the Earth's shape. Type: text Domain: "Clarke 1866" "Geodetic Reference System 80" free text Enumerated values also match "free text" ]]> Element: Semi-major Axis Section: 4.1.4.3 Description: radius of the equatorial axis of the ellipsoid. Type: real Domain: Semi-major Axis > 0.0 Element: Denominator of Flattening Ratio Section: 4.1.4.4 Description: the denominator of the ratio of the difference between the equatorial and polar radii of the ellipsoid when the numerator is set to 1. Type: real Domain: Denominator of Flattening > 0.0 Element: Vertical Coordinate System Definition Section: 4.2 Description: the reference frame or system from which vertical distances (altitudes or depths) are measured. Element: Altitude System Definition Section: 4.2.1 Description: the reference frame or system from which altitudes (elevations) are measured. The term "altitude"' is used instead of the common term "elevation" to conform to the terminology in Federal Information Processing Standards 70-1 and 173. Element: Altitude Datum Name Section: 4.2.1.1 Description: the identification given to the surface taken as the surface of reference from which altitudes are measured. Type: text Domain: "National Geodetic Vertical Datum of 1929" "North American Vertical Datum of 1988" free text Enumerated values also match "free text" ]]> Element: Altitude Resolution Section: 4.2.1.2 Description: the minimum distance possible between two adjacent altitude values, expressed in Altitude Distance Units of measure. Type: real Domain: Altitude Resolution > 0.0 Element: Altitude Distance Units Section: 4.2.1.3 Description: units in which altitudes are recorded. Type: text Domain: "meters" "feet" free text Enumerated values also match "free text" ]]> Element: Altitude Encoding Method Section: 4.2.1.4 Description: the means used to encode the altitudes. Type: text Domain: "Explicit elevation coordinate included with horizontal coordinates" "Implicit coordinate" "Attribute values" Element: Depth System Definition Section: 4.2.2 Description: the reference frame or system from which depths are measured. Element: Depth Datum Name Section: 4.2.2.1 Description: the identification given to surface of reference from which depths are measured. Type: text Domain: "Local surface" "Chart datum; datum for sounding reduction" "Lowest astronomical tide" "Highest astronomical tide" "Mean low water" "Mean high water" "Mean sea level" "Land survey datum" "Mean low water springs" "Mean high water springs" "Mean low water neap" "Mean high water neap" "Mean lower low water" "Mean lower low water springs" "Mean higher high water" "Mean higher low water" "Mean lower high water" "Spring tide" "Tropic lower low water" "Neap tide" "High water" "Higher high water" "Low water" "Low-water datum" "Lowest low water" "Lower low water" "Lowest normal low water" "Mean tide level" "Indian spring low water" "High-water full and charge" "Low-water full and charge" "Columbia River datum" "Gulf Coast low water datum" "Equatorial springs low water" "Approximate lowest astronomical tide" "No correction" free text Enumerated values also match "free text" ]]> Element: Depth Resolution Section: 4.2.2.2 Description: the minimum distance possible between two adjacent depth values, expressed in Depth Distance Units of measure. Type: real Domain: Depth Resolution > 0.0 Element: Depth Distance Units Section: 4.2.2.3 Description: units in which depths are recorded. Type: text Domain: "meters" "feet" free text Enumerated values also match "free text" ]]> Element: Depth Encoding Method Section: 4.2.2.4 Description: the means used to encode depths. Type: text Domain: "Explicit depth coordinate included with horizontal coordinates" "Implicit coordinate" "Attribute values"