# What is a spatial reference scale?

## What is a spatial reference scale?

In GIS, Reference Scale is the scale at which symbols and labels appear on a map at their intended, true size. In ArcGIS Desktop, when reference scale is set to a specific scale, and the zoom extent is changed, the text and symbols change scale along with the display (and accordingly, the map).

## How do you give a shapefile a spatial reference?

- In ArcCatalog, click the shapefile whose coordinate system you want to define.
- Click the File menu and click Properties.
- Click the XY Coordinate System tab.
- Click Select.
- Navigate to the coordinate system you want to use.
- Click the coordinate system.
- Click Add.
- Click OK on the Shapefile Properties dialog box.

**What is WKID in ArcGIS?**

The Well-Known ID (WKID) is a unique number assigned to a coordinate system. You can find the WKID in the Coordinate Systems Details window. Once you know this number, it’s a handy way to search for the coordinate system later.

### What is a spatial reference ID?

A Spatial Reference System Identifier (SRID) is a unique value used to unambiguously identify projected, unprojected, and local spatial coordinate system definitions. These coordinate systems form the heart of all GIS applications.

### What is spatial reference GIS?

A spatial reference is the coordinate system used to store each feature class and raster dataset, as well as other coordinate properties such as the coordinate resolution for x,y coordinates and optional z- and measure(m)-coordinates.

**How do I set spatial references in ArcGIS 10?**

In ArcCatalog or the Catalog window, right-click the raster whose coordinate system you want to define and click Properties. Scroll down to the Spatial Reference section, and click Edit. On the Spatial Reference Properties dialog box, do either of the following: Click Select and choose a predefined coordinate system.

## How do I create a shapefile GIS?

Creating a new shapefile

- Start ArcCatalog.
- Select a folder or folder connection in the Catalog tree.
- Click the File menu, point to New, then click Shapefile.
- Click in the Name text box and type a name for the new shapefile.
- Click the Feature Type drop-down arrow and click the type of geometry the shapefile will contain.

## What is spatial reference in GIS?

**What WKID 4326?**

WKID 4326 is GCS_WGS84 – geographic cords based on the WGS84 datum. WKID 23033 is ED_1950_UTM_33N. A projected UTM coordinate system based on the European datum. You will need a transformation from one datum to the other to get them to match up.

### What is a spatial reference system used for?

A spatial reference system (SRS) or coordinate reference system (CRS) is a framework used to precisely measure locations on the surface of the Earth as coordinates. It is thus the application of the abstract mathematics of coordinate systems and analytic geometry to geographic space.