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What Is UTM?
Lambert Conformal Conic
This is a conic projection, in which a cone intersects Earth at two parallels.
The choice of these tangency lines is important as the distortion on the map
is minimized closer to them and maximized the farther you go from them.
The Lambert Conformal Conic projection is commonly used for United States
geospatial data (and other east-west trending areas).
Transverse Mercator
This is a cylindrical projection, with the tangency being the intersection between the cylinder and Earth. Measurements are most true at that point and
distortions get worse the further east or west the areas displayed on the map
are. It’s considered “transverse” because the cylinder is wrapped around the
poles, rather than the Equator. Transverse Mercator is used for more northsouth trending areas.
GCS coordinates can find locations across the entire globe, down to precise measurements of degrees, minutes, and seconds. However, latitude and
longitude is not the only coordinate system used today—there are several coordinate systems that use a map projection to translate locations on Earth’s
surface to a Cartesian grid system using x and y measurements. Two of the
common grid systems used with geospatial data are UTM and SPCS.
What Is UTM?
The Universal Transverse Mercator (UTM) grid system works by dividing the world into a series of zones, then determining the x and y coordinates for a location in that zone. The UTM grid is set up by translating
real-world locations to where their corresponding places would be on a twodimensional surface (using the Transverse Mercator projection). However,
UTM only covers Earth from between 84° N latitude and 80° S latitude (and
thus couldn’t be used for mapping the polar regions—a different system,
the Universal Polar Stereographic Grid System, is used to find coordinates
on the poles).
The first step in determining UTM coordinates is to find which UTM
zone the location is in. UTM divides the world into 60 zones, with each zone
being 6° of longitude wide (Figure 2.6 on page 40), and each zone is set
up as its own cylindrical projection. These zones are numbered 1 through
60 beginning at the 180th meridian and moving east. For instance, Mount
Rushmore, outside of Keystone, South Dakota, is located in Zone 13. Beijing,
China, is located in Zone 50. Sydney, Australia is in Zone 56. So, the first step
in using UTM is to determine which UTM zone the point you want to locate
is in.
The next step is to determine the x and y grid coordinates of the location. Unlike GCS, which uses degrees, minutes, and seconds, UTM utilizes
Universal Transverse
Mercator (UTM) the
grid system of locating
coordinates across the
globe.
UTM zone one of the
60 divisions of the
world set up by the
UTM system, with each
zone being 6 degrees
of longitude wide.
What Is UTM?
Lambert Conformal Conic
This is a conic projection, in which a cone intersects Earth at two parallels.
The choice of these tangency lines is important as the distortion on the map
is minimized closer to them and maximized the farther you go from them.
The Lambert Conformal Conic projection is commonly used for United States
geospatial data (and other east-west trending areas).
Transverse Mercator
This is a cylindrical projection, with the tangency being the intersection between the cylinder and Earth. Measurements are most true at that point and
distortions get worse the further east or west the areas displayed on the map
are. It’s considered “transverse” because the cylinder is wrapped around the
poles, rather than the Equator. Transverse Mercator is used for more northsouth trending areas.
GCS coordinates can find locations across the entire globe, down to precise measurements of degrees, minutes, and seconds. However, latitude and
longitude is not the only coordinate system used today—there are several coordinate systems that use a map projection to translate locations on Earth’s
surface to a Cartesian grid system using x and y measurements. Two of the
common grid systems used with geospatial data are UTM and SPCS.
What Is UTM?
The Universal Transverse Mercator (UTM) grid system works by dividing the world into a series of zones, then determining the x and y coordinates for a location in that zone. The UTM grid is set up by translating
real-world locations to where their corresponding places would be on a twodimensional surface (using the Transverse Mercator projection). However,
UTM only covers Earth from between 84° N latitude and 80° S latitude (and
thus couldn’t be used for mapping the polar regions—a different system,
the Universal Polar Stereographic Grid System, is used to find coordinates
on the poles).
The first step in determining UTM coordinates is to find which UTM
zone the location is in. UTM divides the world into 60 zones, with each zone
being 6° of longitude wide (Figure 2.6 on page 40), and each zone is set
up as its own cylindrical projection. These zones are numbered 1 through
60 beginning at the 180th meridian and moving east. For instance, Mount
Rushmore, outside of Keystone, South Dakota, is located in Zone 13. Beijing,
China, is located in Zone 50. Sydney, Australia is in Zone 56. So, the first step
in using UTM is to determine which UTM zone the point you want to locate
is in.
The next step is to determine the x and y grid coordinates of the location. Unlike GCS, which uses degrees, minutes, and seconds, UTM utilizes
Universal Transverse
Mercator (UTM) the
grid system of locating
coordinates across the
globe.
UTM zone one of the
60 divisions of the
world set up by the
UTM system, with each
zone being 6 degrees
of longitude wide.