GEOG 121 Project 1:
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The name of my hometown is Bloomfield, NJ.
The map projection that I selected is Mercator. The geometric properties of the globe that are preserved are shape and direction. Size and distance are distorted. I created the map projection with Weinelt, Martin (2002) Online Map Creation. http://www.aquarius.geomar.de/omc/ I prefer the original latitude/longitude system because I learned that system first, and basically grew up with it. I loved looking at maps as a child, and this was the only coordinate system I knew of, so it became ingrained in me. However, it would be impractical for me to carry a globe around with me in case I need to locate a coordinate. I did not learn of the UTM or SPC systems until I took this class, so they are new to me. They seem like good systems, and are probably very useful for the work that they were designed to do. I suppose that I will be learning more about them this semester. It usually takes awhile for me to get use to new things, but I am sure that I will get to like both of the systems as I learn more about them. One of the things I have learned so far is that the UTM system is useful all around the world, but if I am working on a project dealing with just Pennsylvania, then the SPC system will work better.
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| Geographic Coordinates The place name shown on the map above represents the location of my home town. The geographic coordinates of my home town are: |
| Latitude: 40° 48' 00" N, Longitude: 074° 10' 58" W |
| The geographic coordinate system
is the familiar system of latitude and longitude that we see used in the
world. The equator runs east to west and divides the globe into two
equal halves, one north and one south. It is set at 0 degrees.
The two halves are divided into eighty-nine 1 degree sections, with the ninetieth
section being a point at either pole. The prime meridian runs north
to south and divides the globe into equal eastern and western
halves. The each halve is divided into one hundred and eighty 1
degree sections running east and west from the central prime meridian,
which is set at 0 degrees and runs through Greenwich, England. So my
hometown is located forty 1 degree sections north of the 0 degree equator
and seventy four 1 degree sections west of the 0 degree prime
meridian. Each degree can be broken into 60 minutes of measurement,
and each minute can be broken into 60 seconds.
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| UTM Coordinates The UTM coordinates (NAD83) of my home town are: |
| Easting: 568937.320 meters, Northing: 4516876.807 meters, Zone: 18 |
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The Universal Transverse Mercator system has
been designed to map out the entire Earth except for the polar
regions. The system uses a Meractor projection that has been turned
sideways so that the area of least distortion runs north to south.
The earth is divided into 60 north-to-south running zones that extend from
pole to pole. Each zone is six degrees wide. Because the zones
run north to south and are so narrow, each has a 1 in 2,500 level of
accuracy. Each zone is divided into northern and southern
halves. Each zone has a central meridian that is used for mapping
purposes, and the zone's east-to-west origin lies 500,000 meters west of
this meridian. In the northern sections, the north-to-south origin
is the equator, and in the southern sections, the origin is the south
pole. Because of this, every coordinate is represented by a positive
number. Explain what "NAD83" means, and how it differs from "NAD27." NAD83 stands for North American Datum: 1983. In the 1920's, North America was surveyed and mapped out, and the results were recorded as a datum in 1927. The datum was called NAD27 for short. The surveying and mapping was repeated in the early 1980's, with the new datum being completed in 1983 and called NAD83. It officially replaced NAD27.
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| State Plane Coordinates The State Plane coordinates (NAD83) of my home town are: |
| Easting: 176767.406 meters, Northing: 218387.809 meters, Zone: 2900 |
| The State Plane coordinate system
is a system used to map out the fifty states, each of which gets its own
area. Each area is divided into zones, and some states have more
than one zone depending on its size. Two different map projections
are used to map out each state. Tall, long states use a transverse
Mercator projection, and wide states use a Lambert conformal
projection. This minimizes the distortion of each projection for
each state so that each has a 1 in 10,000 level of accuracy. Because
of its accuracy, the State Plane system is popular with individual states
and local planning agencies, but its narrow scope makes it unpopular for
agencies using a national perspective.
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coordinate system has its good and bad points. The geographic
coordinate system works great on spherical surfaces but is not useful for
two-dimensional maps because transposed three-dimensional images have
distortions. The UTM system is great for global mapping, but is not
useful for regional or statewide planning because of its scope. The
SPC system is great for the United States because each state is its own
separate projection and it is more accurate than the UTM, but is not
useful for working with nationwide plans because its scope is so
narrow.
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| Sources: |
| DiBiase, David (2002) Understanding Geographic Data. Module 1: What Are Geographic Data? ESRI Virtual Campus http://campus.esri.com Accessed 23 July 2002. |
| National Geodetic Survey (2002) NADCON - North American Datum Conversion Utility. http://www.ngs.noaa.gov/TOOLS/Nadcon/Nadcon.html Accessed 23 July 2002. |
| National Geodetic Survey (2002) SPC Utilities. http://www.ngs.noaa.gov/TOOLS/spc.html Accessed 23 July 2002. |
| National Geodetic Survey (2002) UTM Utilities. http://www.ngs.noaa.gov/TOOLS/utm.html Accessed 23 July 2002. |
| United States Geological Survey (2002) Geographic Names Information System. http://geonames.usgs.gov Accessed 23 July 2002. |
| Weinelt, Martin (2002) Online Map Creation. http://www.aquarius.geomar.de/omc/ or http://www.gouldcenter.psu.edu/omc/ (North American mirror site). Accessed 23 July 2002. |
