Skill Drill: Clipping the LA City Boundaries to the Census LA County Boundary
You may notice that the boundaries for some cities extend into the ocean. In this scenario, you will want to exclude areas over water. To do this, you will use county boundaries as defined by the U.S. Census Bureau. Navigate to the United States Census Bureau website and locate the cartographic boundary shapefiles for U.S. counties. Choose the 500k resolution and download the file. Decompress the file in your original folder and check the spatial reference. If necessary, use the Project tool to create a copy of the data with the NAD 83 UTM Zone 11 spatial reference system. Add the layer with the correct spatial reference to your Table of Contents. Create a layer based on the Los Angeles County boundary. Clip the LA cities layer and use the Los Angeles County boundary as the clip feature. This clip operation ensures that your density surface model serves your needs while excluding the areas over the Pacific Ocean.