The term GIS stands for geographic information system. Realistically, that doesn't tell you much.
As a concept, GIS is the intersection of data and location.
As a category, GIS is both broad and deep: spanning a huge range of industries and offering hundreds of use-cases.
As a real-world application, GIS is software that captures, manages, and displays data in relation to location.
Because GIS is such a massive category, it's important to remember the following:
- GIS data is always related to a location
- Different organizations both define and use GIS differently
- No two GIS softwares are exactly the same
In this first chapter, we'll answer some basic questions about GIS.
Click any of the links below to jump there directly.
I. How does GIS work?
II. What can you do with GIS?
III. The evolution of GIS
IV. What are the components of GIS?
How does GIS work?
Picture a simple street map.
This map has the name, location, and points of intersection for every street in a given area.
Now, you need to find a specific building. That’s simple. Add buildings, both homes and businesses, on either side of each street.
But what’s under the buildings? Add underground utilities like gas lines and sewer pipes. Above? Power lines and telecom cables.
Suddenly, your simple map is much more complicated. Add another variable, like vegetation data, and your map is now an unusable mess.
Everything you added to your map - buildings, underground utilities, power lines, vegetation - those are all location-based data sets.
The problem is that two-dimensional paper maps can only display a limited number of data sets before becoming disorganized and ineffective.
GIS was invented to solve this problem.
GIS allows you to display location-based data in layers - effectively creating an interactive digital map.
In the next section, we’ll explore the everyday uses for GIS.
What can you do with GIS?
GIS for Simple Mapping
Map making is far and away the most common use for GIS software. In fact, GIS was born from the desire to create maps that could handle large quantities of complex data more effectively.
GIS and mapping are so deeply intertwined, it's essentially impossible to consider one without the other.
Think back to the map in the first section: the one with the streets, buildings, utilities, power lines, and vegetation.
With GIS, you can vizualize all that data in one interactive map. Simply create a digital layer for each data set and then overlay each layer on the original street map.
View each layer independently or in tandem, in order to explore and analyze the relationships between each.
Visualizing data with GIS mapping allows you to:
- Track progress over time
- Analyze spatial relationships
- Manage tasks, projects and teams
- Identify areas of highest risk
- Chart transportation routes
- Compare natural features with human activity
Though mapping is the most common use for GIS, these maps are also the foundation for a variety of other tasks: data management, asset management, change detection, etc.
Data Management with GIS
GIS can be used to manage almost any data type:
- Topographic maps
- Satellite and aerial imagery
- Remote sensor data
- Blueprints and plans
For example, consider a sewer pipeline system.
There are over 2.5 million miles of pipeline in the United States. Imagine all that data in a spreadsheet: lengthy lists of addresses, asset IDs, and notes. It would be completely unmanageable and near impossible to use.
Location-based data requires a visual solution.
For an even simpler example:
Imagine someone gives you their home address, but you don’t a map. You would likely never find the house.
That data point, the address, means little without visual representation.
Though they are excellent at managing data, most legacy GIS systems do not include tools for gathering data. However, as the industry has changed newer platforms are beginning to offer this vital functionality.
GIS for Asset Management
Physical assets tend to be geographically dispersed. Moreover, each one has its own history, specifications, and maintenance schedule. This combination of data and location makes GIS the perfect tool for effective asset management.
GIS helps asset managers make informed operational decisions, organize data efficiently, and reduce costs.
With GIS you can:
- Track asset location
- Create accurate records
- Maintain an up-to-date asset inventory
- Estimate asset lifecycle
- Predict risk of asset breakdown
- Build a data-driven preventative maintenance schedule
Physical assets are a varied category that spans a large range of industries. We'll go over a few of the most common below.
Fixed assets have long life cycles and cannot be quickly converted into cash. It must also be possible to asses a value, meaning that intangible assets are not generally considered fixed. Examples of fixed assets include property, buildings, equipment, etc.
Infrastructure assets are the basic physical structures - roads, bridges, electric grids - required for the operation of a society. Infrastructure asset management focuses on maintaining, upgrading, and replacing these assets in order to improve quality and extend the overall service life.
Public assets are similar to infrastructure assets, but also include schools, parks, airports, and other common areas. Though the primary goal is to extend service life, there is also a focus on improving the community and optimizing use of public funds.
No matter the asset type, modern GIS is the management ideal tool.
Assets are the confluence of data and location. They are spread across large areas and each has it's own individual data set that covers it's history, specifications, and maintenance schedule.
With GIS, you can manage the disperate data with ease.
GIS for change detection
Change detection tracks how an asset or area has changed over time. Though you can track change through a spreadsheet or other linear workflow, these methods are not efficient.
GIS is the most effective way to visually track change across large areas, over long periods of time.
Methods for tracking change include:
- Layering a progression of aerial surveys
- Layering topographic maps
- Overlaying blueprints on aerial surveys
- Geo-tagged photo documentation
- Simple task management
The ability to track change over time, though fairly simple, is incredibly useful for most physical industries.
In construction, you can monitor project progress.
In forestry, you can track the interaction between human activity and the natural world.
In urban planning, you can track whether the identity of a physical asset has changed i.e. if a building that was a restaurant is now a pet store
Like most applications of GIS, change detection takes many forms.
Environmental planning and analysis
The natural environment is expansive, location-specific, and experiences significant change over time. That in mind, the long history between environmental management and GIS should come as no surprise.
Use cases for GIS in environmental planning include:
- Deforestation tracking
- Reforestation planning
- Forest management
- Sustainability planning
- Forest fire mitigation
- Urban growth analysis
Studying the interactions between natural elements is one of the most fascinating applications for GIS in environmental planning.
GIS offers an intuitive way to explore the complex relationships between soil, topography, human land use, and more.
Create a single layer for each element and then view them together in various combinations. This process, not only offers insight into the characteristics of each layer, but helps to reveal the relationship between them.
Urban and regional planning with GIS
Urban planning is the process of designing and deciding land use in cities and municipalities. From transportation, to communication, to distribution - urban planning is multi-faceted and can be quite complex.
Modern GIS is especially useful when it comes to cities undergoing rapid growth.
As a city grows, so do the infrastructure demands. Work orders increase in frequency, scope, and importance.
Energy grids, sewer systems, pipelines, and roads, must all be planned and built in way that is both sustainable and scalable.
The more people driving on a road, or needing to connect to a utility such as water - the more important it becomes that those assets are monitored and maintained effectively.
Using GIS, urban planners can compile all infrastructure data onto a map. With that map they can track current growth, monitor the health of existing infrastructure, and create an effective, scalable plan for future growth.
Emergency and disaster management
One of the most relevant use cases for modern GIS is emergency and disaster management. Natural disaster response protocol must include the following:
- Defining the bounds of the affected area
- Creating an inventory of destroyed property, damaged infrastructure, and missing people
- Prioritizing action steps based on which areas were affected most
- Creating comprehensive response and recovery plans
GIS is the perfect tool to complement one or all of these goals.
Modern GIS offers emergency responders a way to access and share location-based data quickly.
Before GIS was used for response planning, it was used to create hazard maps.
Hazard maps are made by considering data such as landscape, human population, and infrastructure in tandem with natural hazards, such as flooding, forest fires, and earthquakes.
They help emergency planners predict the effects a disaster and make a response plan that addresses highest risk areas first.
The Evolution of GIS
GIS is not a new concept.
In fact, it's been around in various forms for several decades.
ESRI, a pioneer in spatial analysis and creator of the first commercial GIS software, started as research institute in 1965. Their original mission was to "help land use planners and land resource managers make informed decisions." [Source]
In 1981, ESRI released a set of GIS software tools for commercial use.
Since then the platfrom, now called ArcGIS, has grown and evolved into a GIS software powerhouse. Though there are other GIS softwares available, QGIS being one of the most popular, ESRI has consistently maintained market dominance since its initial platform release
Legacy GIS platforms, like ESRI, offers a massive suite of powerful features.
From oceanic basemaps, to 3D spatial analysis - legacy GIS programs offer a dizzying array of robust capabilities.
However, there is a catch. Though these programs are powerful, they're also quite complicated. Until recently, this complexity made the use of GIS fairly exclusive.
To use a legacy GIS software effectively, you need either a degree and/or highly specialized training. More than that, most legacy GIS softwares are not mobile-friendly and rely on local servers to store data.
Using local servers, as opposed to cloud servers, means that changes and updates can only happen locally. As in, you must be sitting at a desktop computer that has your GIS software already set up.
In the same vein, when a program isn't mobile friendly, you are limited to using it on a desktop. This means that data capture in the field is difficult and use is limited to office workers.
All of this said, the GIS software landscape is changing.
The last decade has seen the emergence of GIS systems that provide a lighter, more straightforward experience.
While these programs don't offer the same heavyweight features as a platform like ESRI, they do offer users the ability to manage, organize, and share their location-based data without an advanced degree.
Moreover, most of these modern programs are cloud-based and mobile-friendly.
With cloud-based storage you can review updates in real time, share data faster, and connect all areas of an organization.
With mobile-friendly design, users can take GIS with them into the field - allowing for fast, efficient data capture within the GIS itself.
This evolution is why GIS is so useful across such a wide range of industries.
No matter what kind of GIS you use, there are certain components required in order to be successful.
What are the components of GIS?
Hardware is the physical device on which a GIS platform is used: computer, laptop, tablet, cell phone, etc.
Most legacy GIS programs can only run on a desktop: requiring local servers. They generally can’t be used on mobile devices.
In contrast, most online GIS platforms are cloud-based and mobile-friendly.
GIS software is the digital tool that allows you to capture, organize, analyze, and store data. Though all GIS softwares are different, most provide the following functionality:
- Location-based data management
- Tools for data capture
- Options for visualization
Some, but not all, also offer online/offline features.
Data is arguably the most significant component of any GIS system - it is also the most varied. GIS data can come in the following formats:
- Satellite imagery
- Blueprints and plans
- Topographic maps
- So much more
Without data, GIS is little more than a simple map.
Users are a critical and often overlooked component of GIS.
Legacy GIS was built, and continues to be updated, as a product that can only be used by someone with years of training and experience. Organizations that use GIS frequently, generally hire an in-house GIS specialist.
On the other hand, most modern GIS platforms were built to be accessible: opening up the power of data to everyone.
By now it should be clear that GIS is an expansive topic that can be quite complex. That said, we’ve tried to make it simple.
If you take nothing else moving forward, remember this - GIS software is a way to manage location-based data.
In the next chapter we’ll cover GIS mapping.
Mapping is far and away the most common application for GIS software. In fact, GIS and mapping are so intertwined - it's difficult to consider one without the other.