GIS (Geographic Information System) | National Geographic Society (2023)

ANGeographic Information System (GIS)is a computer system for acquiring, storing, examining, and displayingDatarelated to positions on the earth's surface. By connecting seemingly disconnected data, GIS can help individuals and organizations better understand spatial patterns and relationships.

SAYTechnologyit is acentralpart ofspatial data the infrastructure, which the White House defines as "technology, policies, standards, human resources, and related activities necessary to collect, process, distribute, use, maintain, and preserve spatial data."

GIS may use any information it containssize. Location can be expressed in many different ways, for exampleLargoelongitude, address orPLZ.

Many different types of information can be compared and contrasted using GIS. The system may contain data about individuals, such asPopulation,income, or level of education. It may contain information about thepanorama, such as the location of streams, different types ofVegetation, and various types ofboden. It may contain information about the location of factories,farms, and schools, orravines,streets, and electricpower lines.

With GIS technology, people can compare the location of different things to find out how they relate to each other. For example, use GIS, a singleMapcould include sites that producepollution, such as factories, and places sensitive to pollution, such aswetlandserios. Such a map would help people identify where their water supply is most at risk.

data collection

data formats

GIS applications include bothHardware-eSoftwaresystems. These applications may includecartographicdata, photo data,DigitalData or data in spreadsheets.

Cartographic data are already in map form and may contain information such as location of rivers, roads,hill, evales. Cartographic data can also be includedsearch dataand mapping information that can be entered directly into a GIS.

Photographic interpretation is an important part of GIS. The photographic interpretation includes the analysisaerial photographejudgethe features that appear.

Os dados digitais também podem ser inseridos no GIS. Um exemplo desse tipo de informação são os dados de computador coletados porsatellitesthat's how it isground use—the situation of agricultural holdings,cities, eforests.

remote sensingoffers another tool that can be integrated into a GIS. Remote sensing includes images and other data collected by satellites, balloons, etc.drones.

Finally, GIS can also contain data in tabular or tabular format, such as B. the populationdemographics. Demographics may vary by age, income andethnicityrecent purchases andInternetNavigation settings.

GIS technology makes it possible to overlay all of these different types of information, regardless of their original source or format, onto a single map. GIS uses location as a key index variable to relate these seemingly unrelated data.

Entering information into a GIS is called data collection. Data already in digital format, such as most tables and images taken from satellites, can be easily storedloadedin GIS. Maps have to be there firstscanning, or converted to a digital format.

The two main types of GIS file formats are raster and vector. grid formats arenetworkof cells orpixel. Raster formats are useful for storing different GIS data, for exampleElevationorsatellite image. Vector formats arePolygonuse the dots (calledit) and lines. Vector formats are useful for storing GIS data with the companyLimits, asschool districtsor roads.

spatial relationship

With GIS technology, spatial relationships and networks of lines can be displayed. Spatial relationships can be displayedTopography, such as agricultural fields and streams. You can also view land use patterns, such as B. the location of parks and residential complexes.

Linear networks, sometimes called geometric networks, are often represented in a GIS by roads, rivers, and utility networks. A line on a map can indicate a road or highway. However, GIS layers can specify this streetBordera school district, public park, or other land use or demographic area. Using multiple data acquisitions, the linear network of a river can be mapped in a GIS to show the flow of various tributaries.

GIS has to compile information from all different maps and sourcesconvey a message, so they fit the sameScale. A scale is the relationship between the distance on a map and the actual distance on Earth.

Frequently MRhandleDates because different cards have differentprojections. A projection is the method of transferring information from the Earth's curved surface onto a flat piece of paper or a computer screen. Different types of projectionsto reachthis task in different ways, but all lead to somedistortion. To transfer a curve,three dimensionalMolding on a flat surface inevitably involves stretching some parts and squeezing others.

A world map can show countries the right size or the right shape, but it cannot do both. GIS takes data from maps created with different projections and combines them so that all information can be displayed with a common projection.

GIS maps

Once all the desired data has been entered into a GIS system, it can be combined into a wide variety of individual maps, depending on which data layers are included. One of the most common uses of GIS technology is to compare natural resources with human activities.

For example, GIS maps can show which man-made features are close to certain natural features, e.g. B. which homes and businesses are located in areassusceptibleforinundation.

GIS technology also allows users to “dig deep” into a given area with many types of information. Single city mapsneighborhoodmight relate information such as average income, book sales, orvoting pattern. Any GIS data layer can be added or removed from the same map.

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

GIS technology also allows researchers to observe changes over time. You can use satellite data to study topics like ice sheet advance and retreatPolar-Regions and how this report has changed over time. A police station could investigate changes incrimeData to determine where to goassign toofficers.

An important application of time-based GIS technology is in creatingtime lapse photographywhich shows processes taking place over large areas and over long periods of time. For example, data showing the movement of liquids in the ocean or in the airchainsHelping scientists better understand howmoistureeThermal energymove around the globe.

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

GIS systems are often used to generate three-dimensional images. This is useful, for example, forgeologiststo studyearthquake error.

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

GIS works

People working in many different fields use GIS technology. GIS technology can be used for scientific research,resource management, edevelopmentPlanning.

Lotsretail tradeBusinesses use GIS to determine where new businesses are located.MarketingBusinesses use GIS to decide who to market to in stores and restaurants and where to do that marketing.

Scientists use GIS to compare vital statistics with resources like fresh water.biologistsUse GIS to find animalsMigrationGet together.

city, state orFederalEmployees use GIS to plan their response in the event of anatural disasterlike an earthquakedrilling. GIS maps can show these officers which neighborhoods are most at risk, where to find emergency shelters, and whichstretchPeople must take to achieve security.

engineersUsing GIS technology to support the design, implementation and management of the communication networks for the telephones we use, as well as the infrastructure needed to connect to the Internet. Other engineers may use GIS to design road networks and transportation infrastructure.

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

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Geoscientific Information Center
To find out more about how GIS is being used in your community, contact your nearest Earth Science Information Center (ESIC). US Geological Survey (USGS) personnel answer questions about aerial photographs, maps, satellite imagery, computer programs, data formats, data standards, and digital map data. To contact your local ESIC, call 1-888-ASK-USGS orVisit website.

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