I recently
posted a set of activities based on using web-based GIS tools to teaching spatial thinking using dri.... Viewsheds are another type of buffer. Viewsheds indicate how much terrain is visible from specified locations. Viewsheds are important not only in planning scenic overlooks along trails and highways, but help in everyday decisions such as siting optimal locations for cell phone towers, determining how much terrain would be in shadow if a certain high-rise were to be constructed, helping plan safe roadway curves, and much more.
Open this map to create your own viewsheds.
Teaching spatial concepts with viewsheds.
This map service shades the terrain viewable within 5 miles of your chosen point. Say you are interested in taking photographs in San Francisco but you only have 2 hours to do so, during your airplane’s layover at SFO. You want to be as efficient as possible, choosing locations that allow you a magnificent view. Click in several locations on the map and observe the viewshed after each location. Your viewshed should be greater if you click on one of San Francisco’s many hills. For example, I created the viewshed shown here using the above link.
Judging from the shape of the viewshed, at this point would you be standing on a south-facing hillside or a north-facing hillside? Next, click on the Golden Gate Bridge (leading northward from San Francisco on US 101). Why is the 5 mile viewshed so much greater in area at this location? What is the viewshed from Fisherman's Wharf? From Telegraph Hill? From the Financial District in the streets amongst the tall buildings?
How might you be able to use these viewshed tools in your teaching?