Maps are the traditional output from GIS, but not everyone is well-versed in reading maps. The ultimate goal of GIS is to communicate results. GIS has many ways to communicate results that are not purely cartographic. Check out a few of these methods so that you’re ready to deliver your GIS output to meet the needs of diverse audiences.
- LOOKING FOR ROUTINGS AND TRAVEL DIRECTIONS
GIS provides many opportunities to find shortest routes, fastest routes, and even the most scenic routes along a road network. Such analyses often give you maps that highlight the route. In some cases, a non-graphical list of turn-by-turn directions accompanies the map. Travelers charged with navigation duties often prefer this type of output because they can refer to id and reference the information piece by piece.
Travel directions from a service are normally based on shortest-path distance, but GIS software (and even online mapping systems) allows you to request directions based on time, rather than distance. In some instances, the software even allows you to select which specific streets you want to avoid. Road and highway icons that resemble their respective road signs add a bit of color to the output and can also help the readers find the individual streets.
- GETTING CUSTOMER LISTS AND STATISTICAL DATA
The business GIS user often wants information about customers or potential customers. One typical application uses GIS to search business databases for names, addresses, purchases, e-mail addresses, and a host of other information that a business uses for target advertising. In some situations, every time you scan a purchase and use a credit card, the store records who you are and what you purchased. By comparing that record to demographic data (selected characteristics of the general population), business can actually target different parts of a city for specific marketing campaigns.
Although maps can provide a general description of customer type and location, the busy business professional often wants a report, rather than a map In some cases, the report include maps as part of the document. GIS produces two general types of reports that are suited to business uses:
- Tabular reports: Have a spreadsheet-like layout
- Columnar reports: Have a newspaper column layout
Whether you choose the tabular or columnar-report format, you can sort by any data field that the report contains. For example, you can list cities alphabetically, by population market share, or total volume of business. Another useful tool in the GIS reporting toolkit generates summary statistics, such as sum, mean, range, standard deviation, and minimum and maximum for any data field.
Typically, you can more easily understand summary statistics when they’re presented graphically through bar charts, histograms, line graphs, pie charts, scatterplots, and other forms of non-cartographic graphic output. Most GIS software gives you the option of including both tables and graphs directly on the map itself.
GIS software often presents statistical and tabular data as graphs because graphs provide a visual, easy-to-understand means of communication. Used alone, graphs are handy, but GIS analysts often use them to complement a map because the reader can gather information faster from the graph than from only the map itself. Most GIS software allows you to not only produce maps of GIS data, but also non-spatial data associated with the map. When you base this non-spatial data on the map attributes, the GIS often links that data to the map so that when the data changes, so does the graph. You can even use the same color schemes to make comparisons more natural.
REAL WORLD GIS – In addition to generating maps, a GIS can present virtually any of its data as statistical tables or graphical charts and diagrams. You have a staggering volume of potential output. Here’s a list of some practical and frequently used GIS output that works we in non-cartographic formats:
- Market share by region or quarter
- Number of customers in a particular city, country, state or neighborhood
- Lighting strikes by state
- Customer or potential customer profiles by region
- Crop yields and changes in crop yield by year
- Lists of households not currently subscribing to a newspaper
- Lists of property tax valuation for counties
BENEFITING FROM VIRTUAL OUTPUT
With newer, faster computers and better graphics output devices, GIS has a new set of possibilities for presenting GIS data and analytical results. The following sections show you two major types – animations and flythroughs – both of which involve the development of short movie clips. These types of video output give GIS users a totally different perspective on the data.
ANIMATING YOUR MAPS
GIS animations are a form of geographic visualization that shows dynamic changes to a single map layer or even multiple map layers simultaneously to allow visual comparisons. You most commonly use GIS animations to depict geographic movements (for example, tracking the movement of wildlife) and temporal changes (such as changes in land cover patterns over many years).
Animations show changes – which might take days or weeks to occur – at a fast pace so that you can see tends you might otherwise miss. Alternatively, if you have a lot of data about changes that occur very quickly, you can use animation to present those changes slowly and, again, identify changes you might not otherwise catch. Some circumstances might warrant moving through an animation backward and forward so that you can focus on specific events in the sequence.
REAL WORLD GIS – Here are several possible uses of animations in GIS:
- Tracking hurricane and other weather-related phenomena
- Keeping tabs on the movements of delivery trucks that have built-in GPS units
- Watching changes in climatic data, such as temperature, pressure, and precipitation, over months or even years to observe climate change
- Viewing airline flights to detect possible locations for high traffic concentrations and potential accidents
- Tracking radio-collared wildlife species to identify habitat preferences
- Examining land-use change through time to determine major trends
- Observing how crime hot spots change throughout the day, during the week, or even at different seasons
- Watching changes in market share of your own and competing businesses to identify where new businesses are impacting your sales
Use GIS data presented as animations when you want to focus on pattern changes or feature movements through time.
GETTING THE MOST FROM FLYTHROUGHS
The flythrough is a form of animation that happens in three dimensions. Just like the term says, the flythrough allows you to visually fly through a three-dimensional version of your map. You can find a common example of flythrough in software such as Google Earth, but most professional GIS packages also possess this capability and give you total control over how the flight moves.
REAL WORLD GIS – Flythrough is useful for the following GIS applications:
- Terrain evaluations: To detect landscape features or compare terrain texture (ruggedness or smoothness)
- Urban impact assessment: To show the effect or urban structures on wind
- Political and cultural studies: To illustrate the often radically different patterns that occur as you cross political boundaries worldwide
- Damage estimation: In which flying through an entire valley allows you to observe flood conditions
- Ecological research: Making visual comparisons of elevation levels to changes in the size and composition of vegetation