Esri
esri.com › home › geographic vs projected coordinate systems
Geographic vs Projected Coordinate Systems
March 14, 2022 - The image below shows the Details page for the Fuller (world) coordinate system: The first line tells you that it’s a Projected Coordinate System, as opposed to a GCS.
ArcGIS
desktop.arcgis.com › en › arcmap › latest › map › projections › about-projected-coordinate-systems.htm
What are projected coordinate systems?—ArcMap | Documentation
In a projected coordinate system, locations are identified by x,y coordinates on a grid, with the origin at the center of the grid. Each position has two values that reference it to that central location. One specifies its horizontal position and the other its vertical position.
Videos
06:28
What is a Projected Coordinate System? #coordinatesystem #gis ...
01:02:41
Introducing Coordinate Systems and Map Projections - YouTube
12:34
2 Understanding Geographic and Projected Coordinate Systems & ...
01:00
Choose a projected coordinate system for a map in ArcGIS Pro - YouTube
Coordinates: Introducing Projected Coordinate Systems
05:18
Transform geographic coordinates to projected coordinates using ...
locations on maps using Cartesian coordinates
Wikipedia
en.wikipedia.org › wiki › Projected_coordinate_system
Projected coordinate system - Wikipedia
March 13, 2026 - A projected coordinate system – also called a projected coordinate reference system, planar coordinate system, or grid reference system – is a type of spatial reference system that represents locations on Earth using Cartesian coordinates (x, y) on a planar surface created by a particular ...
U.S. Fish and Wildlife Service
fws.gov › r7 › nwr › Realty › data › LandMappers › Public › Help › HTML › Datumsprojectionsandcoordinatesy.html
Datums, projections, and coordinate systems
Meters or feet are used with projected coordinate systems, such as Alaska Albers Equal Area Conic.
EPSG.io
epsg.io
EPSG.io: Coordinate Systems Worldwide
EPSG.io: Coordinate systems worldwide (EPSG/ESRI), preview location on a map, get transformation, WKT, OGC GML, Proj.4. https://EPSG.io/ made by @klokantech
IBM
ibm.com › docs › en › db2-warehouse
Projected coordinate systems - IBM Documentation
July 13, 2021 - A projected coordinate system is a flat, two-dimensional representation of the Earth. It is based on a sphere or spheroid geographic coordinate system, but it uses linear units of measure for coordinates, so that calculations of distance and ...
QGIS
docs.qgis.org › 3.44 › en › docs › gentle_gis_introduction › coordinate_reference_systems.html
8. Coordinate Reference Systems — QGIS Documentation documentation
April 14, 2026 - Map projections try to portray ... its spherical shape (3D) to a planar shape (2D). A coordinate reference system (CRS) then defines how the two-dimensional, projected map in your GIS relates to real places on the earth....
8th Light
8thlight.com › home › insights › geographic coordinate systems 101: a primer for software generalists
8th Light | Geographic Coordinate Systems 101: A Primer for Software…
September 16, 2024 - The three most common systems are WGS84, EPSG:4326, and EPSG:3857. Knowingly, or unknowingly, all web developers will come across these. WGS84 and EPSG:4326 are geographic CRS. It means that they use latitude and longitude coordinates to specify a location on the surface of the earth.
University of Washington
courses.washington.edu › gisintro › wordpress › wp-content › uploads › 2013 › 05 › Projections-and-Coordinate-Systems.pdf pdf
Projections and Coordinate Systems Discussion
In this image, Washington state is projected to State Plane North (NAD83). All of the locations on the map are · now referenced in Cartesian coordinates, where the origin lies several hundred miles off the Pacific coast. Some measurement framework systems define both projections and coordinate systems.
Reddit
reddit.com › r/gis › struggling to understand geographical vs projected coordinate systems
r/gis on Reddit: Struggling to understand geographical vs projected coordinate systems
August 11, 2021 -
Hello, I was hoping to ask this community for some help with some confusion I am having with my layers not matching up in QGIS, and specifically where I am going wrong with my understanding of coordinate reference systems, geographical reference systems, and projected coordinate systems. I was hesitant to post this, since of course there is so much content online that explains this, but I still am unfortunately struggling to understand why I am not able to apply these concepts. I will watch so many tutorial videos that start with the idea of "picture the earth like a sphere, such as an orange peel, you can't just lay the whole thing out flat!", and then just totally get lost afterwards. This confusion popped up again as I am trying to create buffers around centroids, and perform zonal statistics with an underlying raster layer, and the points are just not overlapping with the raster layer, and so I was hoping to ask for some help here so that I might be able to understand these concepts from an applied perspective.
So I have these layers, showing a polygons layer overlapped onto a clipped raster layer.
Looks good to me, though the problem is when I want to make my buffers. I find the centroids of these polygons, and try to draw buffers around each of them, only to find that the Distance is in degrees, when I want meters. From my understanding, to be able to switch the unit of measurement here from degrees to meters, I would need to "project" the polygons layer. Though I am confused since it appears that my layers already are projected, I think.
For reference, the CRS of my raster layer is:
EPSG:32618 - WGS 84 / UTM zone 18N - Projected
and the CRS of my polygons layers is:
Unknown CRS: GEOGCRS["WGS84(DD)",DATUM["WGS84",ELLIPSOID["WGS84",6378137,298.257223563,LENGTHUNIT["metre",1,ID["EPSG",9001]]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433]],CS[ellipsoidal,2],AXIS["geodetic longitude",east,ORDER[1],ANGLEUNIT["degree",0.0174532925199433]],AXIS["geodetic latitude",north,ORDER[2],ANGLEUNIT["degree",0.0174532925199433]]] - Projected
I tried changing my polygons layer to the same CRS as my raster layer, but then the polygons layer disappeared from being directly overlapped with the raster layer! That is what I don't understand. My raster layer and my polygons layer are now within the same CRS, yet do not overlap on my map. Degrees was changed to meters as the "Unit" for my polygons layer, so at least that is some progress, but I cannot figure out why my polygons and raster layer do not overlap.
Could someone please help me understand where I might be going wrong here? Is this perhaps some issue with my understanding of the difference between geographical and projected coordinate reference systems that I might be totally missing here?
Thanks!
Top answer 1 of 4
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Your shapefile is in a geographical coordinates, WGS84, save and reopen it in UTM projection. Alternatively, divide your buffer distance by 111120 (converting degrees to metres).
2 of 4
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Seems like your polygons layer isn't being projected properly. Maybe switch it to EPSG:4326, which is the proper standard for the WGS84 coordinate reference system. Pro tip: when a layer's CRS is "unknown" you usually need to set it to something different, because most usually it will project incorrectly, or do all sorts of funny things. Thanks for detailedly exposing your problem. One more thing, you don't really need to remember the implementation details and concepts of coordinate systems. Or even understand them that thoroughly, anymore. These are formulaic processes that are fully automated today. (Nevertheless, the knowledge you have about them helped you identify your problem, so I might be a bit wrong in saying this…)
ArcGIS Pro
pro.arcgis.com › en › pro-app › latest › help › mapping › properties › coordinate-systems-and-projections.htm
Coordinate systems, map projections, and transformations | ArcGIS Pro documentation
May 4, 2026 - Download the list of supported geographic and vertical coordinate systems. Projected coordinate systems are planar systems that use linear measurements for the coordinates rather than angular units. A projected coordinate system is composed of a geographic coordinate system and a map projection ...
Esri Support
support.esri.com › en-us › gis-dictionary › projected-coordinate-system
Projected Coordinate System Definition | GIS Dictionary
A two-dimensional Cartesian coordinate system that uses x, y, and z coordinates to represent point, line, and area feature locations in two or three dimensions. A projected coordinate system is define
Intro to GIS
mgimond.github.io › Spatial › chp09_0.html
Chapter 9 Coordinate Systems | Intro to GIS and Spatial Analysis
Also note the 0.0005° longitudinal offset between both reference systems. The surface of the Earth is curved, but maps are flat. A projected coordinate system (PCS) provides a framework for identifying locations and measuring features on a flat (map) surface.
IBM
ibm.com › docs › en › db2w-as-a-service
Projected coordinate systems
A projected coordinate system is a flat, two-dimensional representation of the Earth. It is based on a sphere or spheroid geographic coordinate system, but it uses linear units of measure for coordinates, so that calculations of distance and area are easily done in terms of those same units.
Utah State University
usu.edu › geospatial › tutorials › core-concepts › projected-coordinate-systems
Projected Coordinate Systems | Geospatial | USU
In the example above, the scale factor of 0.9996 means that there is a compression of the map at the central meridian (the location farthest from the secant lines) of the UTM coordinate system where 100 meters on the earth’s surface will measure 99.96 meters on the map at the central meridian. To minimize the amount of natural distortion that comes with projecting curved data to a flat surface, we can focus in on a small area of interest.
NOAA
ngs.noaa.gov › NCAT
NGS Coordinate Conversion and Transformation Tool (NCAT)
Enter your latitude, longitude and orthometric height. Towards the bottom of the screen you see an option to choose an input geopotential or vertical datum. Pick NGVD 29 from the dropdown and click submit. You should see transformed height under "Transformed Coordinate".
Hunter College Geography
geo.hunter.cuny.edu › ~jochen › gtech201 › lectures › lec6concepts › 06 - Projected coordinate systems.html
06 - Projected coordinate systems
A projected coordinate system is a reference system for identifying locations and measuring features on a flat (map) surface. It consists of lines that intersect at right angles, forming a grid.
Virtual Surveyor
support.virtual-surveyor.com › support › solutions › articles › 1000261350-the-difference-between-geographic-and-projected-coordinate-systems-
The Difference Between Geographic and Projected Coordinate Systems? | Virtual Surveyor : Support Portal
October 6, 2022 - A projected coordinate system is constituted by a geographic coordinate system from which it is projected (GEOGCS) and other projection parameters like the measurement unit (like meter or US Survey Foot), the projection technique, and its projection parameters.
Oceanhealthindex
oceanhealthindex.org › news › crs_deep_dive
Coordinate Reference Systems: Ensuring Accuracy in Spatial Analysis | OHI
August 30, 2024 - Geographic coordinate systems describe locations on earth using a three-dimensional reference, and are used along with a specified map projection to create a projected coordinate system, which describes the same information on a two-dimensional surface (1) .
Propeller
propelleraero.com › home › resource center › what is the difference between a map projection and a coordinate system?
What is the Difference Between a Map Projection and a Coordinate System?
July 10, 2022 - Projected coordinate systems can be more useful for worksites over geographic coordinate systems because they have less local distortion. For example, a local grid can be as small as the size of a single site, which reduces projection distortion considerably.