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Example GIS map layer (water resources and rivers).

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Example GIS map overlaying the layers.

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The link below is to a video (3:46) showing the possibilities of geographic information systems.

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Non-profit organization working with conservationist using GIS.

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Too Many Variables:  GIS has many variables that contribute to the analysis. Calculations may be misinterpreted and/or not all the variables are acknowledged when creating the map. For example, shortfalls when calculating optimal transportation routes did not include factors such as land use or average speed of vehicles (Abousaeidi et al., 2016). This would limit the data; potentially affecting the results.

Estimations:  Databases use given information to assess geographic information, but do not have accurate calculations for information outside the database. In a study by Bundschuh et al. (2016), a GIS map was developed to indicate the probability of stream types receiving crop material. If crop material is exposed to pesticides, these pesticides may enter bodies of water through wind patterns or plant runoff. It is important to identify the exposed water sources to begin treatment and reduce contamination. GIS can estimate which streams and areas are exposed, but may be limited to identifying small lakes and ponds (Bundschuh et al., 2016). Further research should be developed to be all inclusive of the parameters, thus we would not limit the affect of organisms living in other water sources.

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Decision making:  GIS maps are working to solve issues and find the source of current societal problems (e.g. pesticide use near streams or development in ecologically sensitive areas). It creates a database for the number of resources, where they are located, and how it is impacting the environment. For example, González, Bonaccorso, and Papeş (2015) analyzed land cover over a 34 year period to identify areas in need of conservation and restoration.

Reducing Emissions:  Technology can reduce emissions by mapping out the most efficient ways of transportation while considering both the shortest distance and traffic conditions in spatial analysis. Not only would this create less waste, but recent studies make it possible for companies to preserve food and products in delivery (Abousaeidi, Fauzi, & Muhamad, 2016).

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The following link is to a National Geographic article about GIS. It also has interactive activities that can be implemented in the classroom.

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A geographic information system (GIS) is a computer system for capturing, storing, checking, and displaying data related to positions on Earth's surface. By relating seemingly unrelated data, GIS can help individuals and organizations better understand spatial patterns and relationships.

GIS technology is a crucial part of spatial data infrastructure, which the White House defines as "the technology, policies, standards, human resources, and related activities necessary to acquire, process, distribute, use, maintain, and preserve spatial data."

GIS can use any information that includes location. The location can be expressed in many different ways, such as latitude and longitude, address, or ZIP code.

Many different types of information can be compared and contrasted using GIS. The system can include data about people, such as population, income, or education level. It can include information about the landscape, such as the location of streams, different kinds of vegetation, and different kinds of soil. It can include information about the sites of factories, farms, and schools; or storm drains, roads, and electric power lines.

With GIS technology, people can compare the locations of different things in order to discover how they relate to each other. For example, using GIS, a single map could include sites that produce pollution, such as factories, and sites that are sensitive to pollution, such as wetlands and rivers. Such a map would help people determine where water supplies are most at risk.

GIS applications include both hardware and software systems. These applications may include cartographic data, photographic data, digital data, or data in spreadsheets.

Cartographic data are already in map form, and may include such information as the location of rivers, roads, hills, and valleys. Cartographic data may also include survey data, mapping information which can be directly entered into a GIS.

Photographic interpretation is a major part of GIS. Photo interpretation involves analyzing aerial photographs and assessing the features that appear.

Digital data can also be entered into GIS. An example of this kind of information is computer data collected by satellites that show land use-the location of farms, towns, and forests.

Remote sensing provides another tool that can be integrated into a GIS. Remote sensing includes imagery and other data collected from satellites, balloons, and drones.

Finally, GIS can also include data in table or spreadsheet form, such as population demographics. Demographics can range from age, income, and ethnicity to recent purchases and Internet browsing preferences.

GIS technology allows all these different types of information, no matter their source or original format, to be overlaid on top of one another on a single map. GIS uses location as the key index variable to relate these seemingly unrelated data.

Putting information into GIS is called data capture. Data that are already in digital form, such as most tables and images taken by satellites, can simply be uploaded into GIS. Maps, however, must first be scanned, or converted to digital format.

The two major types of GIS file formats are raster and vector. Raster formats are grids of cells or pixels. Raster formats are useful for storing GIS data that vary, such as elevation or satellite imagery. Vector formats are polygons that use points (called nodes) and lines. Vector formats are useful for storing GIS data with firm borders, such as school districts or streets.

GIS technology can be used to display spatial relationships and linear networks. Spatial relationships may display topography, such as agricultural fields and streams. They may also display land-use patterns, such as the location of parks and housing complexes.

Linear networks, sometimes called geometric networks, are often represented by roads, rivers, and public utility grids in a GIS. A line on a map may indicate a road or highway. With GIS layers, however, that road may indicate the boundary of a school district, public park, or other demographic or land-use area. Using diverse data capture, the linear network of a river may be mapped on a GIS to indicate the stream flow of different tributaries.

GIS must make the information from all the various maps and sources align, so they fit together on the same scale. A scale is the relationship between the distance on a map and the actual distance on Earth.

Often, GIS must manipulate data because different maps have different projections. A projection is the method of transferring information from Earth's curved surface to a flat piece of paper or computer screen. Different types of projections accomplish this task in different ways, but all result in some distortion. To transfer a curved, three-dimensional shape onto a flat surface inevitably requires stretching some parts and squeezing others.

A world map can show either the correct sizes of countries or their correct shapes, but it can't do both. GIS takes data from maps that were made using different projections and combines them so all the information can be displayed using one common projection.

Once all of the desired data have been entered into a GIS system, they can be combined to produce a wide variety of individual maps, depending on which data layers are included. One of the most common uses of GIS technology involves comparing natural features with human activity.

For instance, GIS maps can display what manmade features are near certain natural features, such as which homes and businesses are in areas prone to flooding.

GIS technology also allows to "dig deep" in a specific area with many kinds of information. Maps of a single city or neighborhood can relate such information as average income, book sales, or voting patterns. Any GIS data layer can be added or subtracted to the same map.

GIS maps can be used to show information about numbers and density. For example, GIS can show how many doctors there are in a neighborhood compared with the area's population.

With GIS technology, researchers can also look at change over time. They can use satellite data to study topics such as the advance and retreat of ice cover in polar regions, and how that coverage has changed through time. A police precinct might study changes in crime data to help determine where to assign officers.

One important use of time-based GIS technology involves creating time-lapse photography that shows processes occurring over large areas and long periods of time. For example, data showing the movement of fluid in ocean or air currents help scientists better understand how moisture and heat energy move around the globe.

GIS technology sometimes allows users to access further information about specific areas on a map. A person can point to a spot on a digital map to find other information stored in the GIS about that location. For example, a user might click on a school to find how many students are enrolled, how many students there are per teacher, or what sports facilities the school has.

GIS systems are often used to produce three-dimensional images. This is useful, for example, to geologists studying earthquake faults.

GIS technology makes updating maps much easier than updating maps created manually. Updated data can simply be added to the existing GIS program. A new map can then be printed or displayed on screen. This skips the traditional process of drawing a map, which can be time-consuming and expensive.

People working in many different fields use GIS technology. GIS technology can be used for scientific investigations, resource management, and development planning.

Many retail businesses use GIS to help them determine where to locate a new store. Marketing companies use GIS to decide to whom to market those stores and restaurants, and where that marketing should be.

Scientists use GIS to compare population statistics to resources such as drinking water. Biologists use GIS to track animal migration patterns.

City, state, or federal officials use GIS to help plan their response in the case of a natural disaster such as an earthquake or hurricane. GIS maps can show these officials what neighborhoods are most in danger, where to locate emergency shelters, and what routes people should take to reach safety.

Engineers use GIS technology to support the design, implementation, and management of communication networks for the phones we use, as well as the infrastructure necessary for Internet connectivity. Other engineers may use GIS to develop road networks and transportation infrastructure.

There is no limit to the kind of information that can be analyzed using GIS technology.

Term

Part of Speech

Definition

Encyclopedic Entry

time-lapse photography

Noun

photographing of a slow and continuous process at regular intervals, for projection at a higher speed.

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A geographic information system (GIS) is a computer system for capturing, storing, checking, and displaying data related to positions on Earth's surface. By relating seemingly unrelated data, GIS can help individuals and organizations better understand spatial patterns and relationships.

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Abousaeidi, M., Fauzi, R., & Muhamad, R. (2016). Geographic Information System (GIS) modeling approach to determine the fastest delivery routes. Saudi Journal of Biological
Sciences, 23(5), 555-564. doi:10.1016/j.sjbs.2015.06.004
Bundschuh, R., Kuhn, U., Bundschuh, M., Naegele, C., Elsaesser, D., Schlechtriemen, U., . . . Hofmann, F. (2016). Prioritizing stream types according to their potential risk to receive
crop plant material — A GIS-based procedure to assist in the risk assessment of genetically modified crops and systemic insecticide residues. Science of The Total
Environment, 547,  226-233. doi:10.1016/j.scitotenv.2015.12.124
Esri. (2012, December 5). A map for every story. Retrieved February 23, 2017, from http://www.esri.com/videos/watch?videoid=2054&isLegacy=true&title=a-map-for-every-story
González, M. P., Bonaccorso, E., & Papeş, M. (2015). Applications of geographic information systems and remote sensing techniques to conservation of amphibians in
northwestern Ecuador.Global Ecology and Conservation, 3, 562-574. doi:10.1016/j.gecco.2015.02.006
Izadikhah, M., & Saen, R. F. (2016). A new preference voting method for sustainable location planning using geographic information system and data envelopment analysis.
Journal of Cleaner Production, 137, 1347-1367. doi:10.1016/j.jclepro.2016.08.021
Jenkins, J. A., Hartley, S. B., Carter, J., Johnson, D. J., & Alford, J. B. (2011). A geographic information system tool for aquatic resource conservation in the Red and
Sabine River watersheds of the southeast United States. River Research and Applications, 29(1), 99-124. doi:10.1002/rra.1580
National Geographic. GIS (Geographic Information System). Retrieved February 17, 2017, from http://www.nationalgeographic.org/encyclopedia/geographic-
information-system-gis/
Society for Conservation GIS. Retrieved February 20, 2017, from https://www.scgis.org/

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Geographic information systems (GIS) uses software technology to layer data, creating an all encompassing map of Earth. GIS is working to solve unanswered questions through maps. This technology allows us to see and understand the world around us. It is now accessible to have a range of information (e.g. locations of structures and resources, relationships between plant and animal species, demographic data, urban impacts, etc.) to better assess what actions to take and the types of resources that are globally needed. Geographic information systems have proven success for better decision making strategies and to better assess resource impacts (Jenkins, Hartley, Carter, Johnson, & Alford, 2011).