Which coordinate system uses time as an ordinate

With the general agreement that the Earth was, in fact, round, a different methodology needed to be developed. The system that has been developed over many centuries is called latitude and longitude.

The first convention to be developed was latitude. This is based on long term astronomical observations about how the sun is perceived to move across the surface of the Earth. It was agreed that a line around the centre of the Earth would be called the Equator.

From the Equator a series of parallel lines were recognised with the most northern and southern points being called the North Pole and South Pole. Because lines of latitude are like slices through the Earth they have different lengths.

For example:. Defining longitude was much more difficult, as it is could not be based on observations of movement of the sun. The convention eventually agreed upon was to have a series of radiating lines which run vertically around the Earth. They connected at both ends — i. These are pointed at their ends and broadest in the middle. All three systems are illustrated in Figure A1. Cylindrical coordinates can be thought of as an extension of the polar coordinates.

Cylindrical coordinates are useful for describing situations with azimuthal symmetry, such as the motion along the surface of a cylinder.

The radius is the distance between the point and the origin. The azimuthal angle is defined in the same way as in polar coordinates. There are more than 4, coordinate systems in the ArcGIS platform, so it is likely you'll find one to match your data. If not, you can create a custom coordinate system to display the data. ArcGIS Pro reprojects data on the fly so any data you add to a map adopts the coordinate system definition of the first layer added.

As long as the first layer added has its coordinate system correctly defined, all other data with correct coordinate system information reprojects on the fly to the coordinate system of the map. This approach facilitates exploring and mapping data, but it should not be used for analysis or editing, because it can lead to inaccuracies from misaligned data among layers. Data is also slower to draw when it is projected on the fly. If you intend to perform analysis or edit the data, first project it into a consistent coordinate system shared by all your layers.

This creates a new version of your data. Download the list of supported projected coordinate systems. See a list of all the supported map projections. After defining the coordinate system that matches your data, you may still want to use data in a different coordinate system.

This is when transformations are useful. Australian Geodetic Datum is designed to fit the earth snugly around Australia, giving you good precision for this continent but poor accuracy anywhere else. The GCS is what ties your coordinate values to real locations on the earth.

The coordinates You still need to know which GCS it is in before you know where it is on Earth. Once your data knows where to draw, it needs to know how. Imagine peeling an orange and trying to lay the peel flat on a table. You can get close, but only if you start tearing the peel apart. This is where map projections come in. They tell you how to distort the earth—how to tear and stretch that orange peel—so the parts that are most important to your map get the least distorted and are displayed best on the flat surface of the map.

Some are good for preserving areas on your map, others at preserving angles or distances. Your data must have a GCS before it knows where it is on earth. Projecting your data is optional, but projecting your map is not. Maps are flat, so your map must have a PCS in order to know how to draw. Click the green Details link.