While using ArcGIS, different layers may have different properties. If a layer does not match the properties of the one below, it can become misaligned. Misaligning a layer can distort distance and data densities over that projection, making the map harder to accurately analyze.
Luckily in the software, there are two ways to fix this misalignment. ArcToolbox is a tool built into the software that allows you to modify the properties (i.e. the scale, projection type, etc.) with a few clicks of the mouse. All one needs to know is the native projection and, or, scale of the base map ( the bottom layer which other layers match properties with). Locate the tool on the toolbar, navigate to the projections folder, then click project. A window will pop-up and all the user has to do is input the information of the layer being projected, then choose a projection to match the base-layer. Click ‘OK’ and move on.
The second procedure to fixing misaligned data is called ‘projecting on the fly’. Ultimately, the end result is the same if you used the ArcToolbox method, however, this method is more hands-on and allows you to understand the process better. By right clicking on the base layer, then selecting the ‘properties’ tab, the software will open a window. Navigate to the ‘general’ tab and it should display the projection, datum, and scale of the layer. To project on the fly, follow the aforementioned steps for the base layer. Then, add the layer you need to change to the table of contents and repeat the same steps. Once there, click on the drop-down folders under ‘projections’ and find the one identical to that of the base layer. Click on it, then hit ‘apply’ in the lower right corner of the window. The map will accept these changes and now the projections match. No more unwanted distortion.
