A good map provides users with the answer to questions that were defined by the maps creator. A great map allows users to get answers to questions that they’ve defined themselves.
Web mapping is about more than just pretty pictures. The true power of a web map is putting the power of GIS in the hands of someone who might not even know what GIS stands for, never mind having the ability to perform spatial queries.
If we strip back all the vendor jargon and all of the unnecessary complexities, what is the purpose of a GIS ? For me the purpose of a GIS is to answer questions about our physical world using the visual medium of a map.
Web maps are now making it possible for anyone with a web browser to ask the kind of complex questions that would previously have required complex “enterprise” tools and the skilled professionals who know how to use them. Removing these barriers and putting GIS into the hands of everyone is a revolution.
The map below is a perfect example. In addition to the layer which shows the buildings of Manhattan by their total commercial area, a user can also use the “Floorspace Analysis Tool” to get answers to questions about commercial floorspace in Manhattan.
Try selecting the “Proximity Tool” in the lower right of the map below and try it for yourself.
As you can see the tool is focused and very easy to use, but still allows users who may not even know what GIS is to enjoy it’s power. This web map was built in under half an hour using Mango without writing a single line of code.
Of course summarizing data is one of the less complex tasks common of a GIS, but it’s possible to allow non-expert users to ask more complex questions such as those that involve the spatial relationship between features in two different layers?
The answer is “Yes”, as long as we keep our tools super focused it’s possible to make even complex queries accessible to non-expert users. Take the map below, which allows users to discover the relationship between referral hospitals and health centers in Cambodia. Using the Health Facility Location Analysis Tool in the bottom right corner users are able to get answers to complex spatial questions.
Try the tool. Select all of the referral hospitals and then see if you can find all of the health centers that are more than 20km from those referral hospitals. Next, filter the results so you only see the health centers in the province of Battambang.
By giving users the power to answer their own questions we are increasing the effectiveness and efficiency of our GIS efforts and putting an important analytical capability into the hands of stakeholders and decision makes, who ordinarily might not have access to such tools and information.