What is GIS
From Wiki
From the US Geological Survey: What is GIS?
Geographic Information Systems and Sciences
Geographic information systems (GIS) are computer based systems for capturing, storing, analyzing and managing data and associated attributes which are spatially referenced to the earth. In the strictest sense, any computer system capable of integrating, storing, editing, analyzing, sharing, and displaying geographically-referenced information, is a GIS. In a broader sense, GIS consists of a collection of tools and methods that allow users to
- create and edit spatial data
- interactively create queries
- analyze spatial information
- create maps and other visual products, and
- present the results of all these operations.
These tools and methods are often used for decision support in a wide range of applications. "Geographic information science" ("GIScience", sometimes also identified with "GIS") is the science underlying these methods and systems, taught in degree programs at many universities. Among its most important topics are
- visualization of large and complex datasets,
- spatial statistics and spatial information analysis, and
- spatial decision support.
GIS technology is used in scientific research and analysis, and in visualization and presentation. Atmospheric science, weather forecasting, climatology, and environmental science are especially important fields using GIS tools.
Although GIS originated in computer-aided cartography and route planning, its many applications in industry and government now include
- resource exploration and management
- infrastructure, facilities, and asset management
- industrial operations support
- transportation and urban planning
- environmental impact assessment
- public safety, security and criminology
- market analysis
For example, GIS might allow emergency planners to easily calculate emergency response times in the event of a natural disaster, a GIS might be used to find wetlands that need protection from pollution, or a GIS can be used by a company to find new potential customers similar to the ones they already have and project sales due to expanding into that market.
- EEAS 87.504 Introduction To GIS is offered each fall as a laboratory course.
Remote sensing and GIS
Remote sensing is "the measurement or acquisition of information of some property of an object or phenomenon, by a recording device that is not in physical or intimate contact with the object or phenomenon under study" (Colwell, 1997). GIS data can be collected by ground survey methods that require physical presence (including GPS position data collection, which also involves a remote spaceborne segment) but aerial and satellite imaging methods are now far more economical and commonplace. Remote sensing is therefore an important GIS technology field if only in contributing GIS data; and registration and identification of aerial and satellite imagery of many sorts (a type of image processing often called "photogrammetry") is an important part of GIS operations.
But spatial remote sensing and image analysis is an important field in its own right, with many problems in active research and applications. Physical imaging in many spectral bands with many sensor technologies, including photography, digital imaging, microwave, and radar, provides much of the data for GIS systems, and sensor science and technology is fundamental to understanding that data. Computer image processing for correction, registration, and enhancement is necessary to produce usable data from many sensors. Classification and pattern recognition processing is often necessary to identify features in images, and integration of these features with GIS data from other sources, especially ground surveys, requires interpretation and analysis, some of which can be automated. Remote sensing systems in national security applications have been best known for intelligence gathering using such automation to support human analysts, but are also used for direct command and control in military operations. Remote sensing is a fundamental tool in geoscience and its engineering applications, esp. mineral exploration. Remote sensing also provides important information for study of land cover and environmental impacts in environmental science and engineering, including vegetation, water resources, soils and minerals, and urban and other human-built environment. Finally, remote sensing and analysis of environmental, meteorological and climate data is fundamental to understanding atmospheric phenomena and climate, and is an essential tool for decision support in climate change risk analysis and mitigation.
EEAS 87.506 Introduction to Photogrammetry and Remote Sensing is a graduate level lab course offered through the UML School of Continuing Studies.
