Special Topics: Geospatial Technology for
Earth and Environmental Sciences
Sep 13, 15, 20, 22, 27 of 2011
Hongjie Xie
Laboratory for Remote Sensing and Geoinformatics
Department of Geological Sciences
University of Texas at San Antonio
Grading from my part
• Participating class for questions and discussions
– Including attendance
• Final exam including questions from each section
(~30 minutes for each section)
What is geospatial technology?
• Geospatial Technology, commonly known as geoinformatics,
refers to technology used for visualization, measurement, and
analysis of features or phenomena that occur on the earth. This
terminology has become common in the United States, and is
synonymous with Spatial Information Technology.
• Geospatial technology includes three different technologies that
are all related to mapping features on the surface of the earth.
These three technology systems are GPS (global positioning
systems), GIS (geographical information systems), and RS (remote
sensing).
GPS
• Global Positioning System (GPS) is a space-based global navigation
satellite system that provides reliable location and time information in all
weather and at all times and anywhere on or near the Earth when and
where there is an unobstructed line of sight to four or more GPS satellites.
It is maintained by the United States government and is freely accessible
by anyone with a GPS receiver.
• GPS was created and realized by the U.S. Department of Defense (DOD)
and was originally run with 24 satellites. It was established in 1973 to
overcome the limitations of previous navigation systems
• In addition to GPS, other systems are in use or under development. The
Russian GLObal NAvigation Satellite System (GLONASS) is for use by the
Russian military. There are also the planned Chinese Compass navigation
system and Galileo positioning system of the European Union (EU).
GIS
•
Geographic information systems (GIS) or geospatial information systems is a set of tools that captures,
stores, analyzes, manages, and presents data that are linked to location(s). In the simplest terms, GIS is
the merging of cartography, statistical analysis, and database technology. GIS may be used in geography,
cartography, remote sensing, land surveying, public utility management, natural resource management,
precision agriculture, photogrammetry, urban planning, emergency management, navigation, aerial
video, and localized search engines.
•
As GIS can be thought of as a system, it digitally creates and "manipulates" spatial areas that may be
jurisdictional, purpose or application oriented for which a specific GIS is developed. Hence, a GIS
developed for an application, jurisdiction, enterprise, or purpose may not be necessarily interoperable
or compatible with a GIS that has been developed for some other application, jurisdiction, enterprise, or
purpose. What goes beyond a GIS is a spatial data infrastructure (SDI), a concept that has no such
restrictive boundaries.
•
Therefore, in a general sense, the term describes any information system that integrates, stores, edits,
analyzes, shares, and displays geographic information for informing decision making. GIS applications are
tools that allow users to create interactive queries (user-created searches), analyze spatial information,
edit data, maps, and present the results of all these operations.[1] Geographic information science is the
science underlying the geographic concepts, applications and systems.[2] GIS can be studied in degree
and certificate programs at many universities.
Remote sensing
• Remote sensing is the small- or large-scale acquisition of information of
an object or phenomenon, by the use of either recording or real-time
sensing device(s) that are wireless, or not in physical or intimate contact
with the object (such as by way of aircraft, spacecraft, satellite, buoy, or
ship). In practice, remote sensing is the stand-off collection through the
use of a variety of devices for gathering information on a given object or
area. Thus, Earth observation or weather satellite collection platforms,
ocean and atmospheric observing weather buoy platforms, the
monitoring of a parolee via an ultrasound identification system, Magnetic
Resonance Imaging (MRI), Positron Emission Tomography (PET), Xradiation (X-RAY) and space probes are all examples of remote sensing.
• In modern usage, the term generally refers to the use of imaging sensor
technologies including: instruments found in aircraft and spacecraft as
well as those used in electrophysiology, and is distinct from other imagingrelated fields such as medical imaging.