Remote Sensing & GIS Flashcards
Combines location and information about the location
Ability to analyze information
Analyze as many layers of information at ocne
Can overlay different spatial information at once
GIS
Geographic Information System
information associated with an underlying geography or description of location
Spatial Information
the science that deals with the construction, use, and principles behind maps and map use
Cartography
Imaginary lines that runs horizontally
69 miles or 111 km apart
Latitude
Imaginary lines that runs vertically and also known as meridians
(69 miles or 111 km apart)
Longitude
0 degree of Longitude is located at ______ and continues 180 degrees east
and west where they meet and form the
International Date line in the Pacific Ocean
Greenwich England
It provides essential information for the map reader
Map Legend
Ratio between distance on a paper map and distance of the same stretch in actual terrain
Map Scale
The accuracy with which a given map scale can depict the location and shape of map features
Resolution
the minimum size of objects that can be detected by a sensor system
Spatial Resolution
is used to portray all or part of round Earth on a flat surface map
Map Projection
Map Projection that has
equally spaced longitudes unequally spaced latitudes scale is true along equator shape and scale distortions increase near poles shows true direction UTM
Cylindrical Projection
Map projection that results from projecting a spherical surface onto a cone
Conic Projection
Map projection resulting from projecting a spherical surface onto a plane
Best for polar or circular regions
Azimuthal (Planar) Projection
used to represent the locations of geographic features, imagery, and observation such as GPS locations within a common geographic framework
Reference System
Map projection best for mid-latitudes with an East-West orientation like Canada
Conic Projection
a combination of factors; ellipsoud, geoid, coordiate system and projection that identify a point on a sphere and on a two dimensional representation of the sphere
Spatial Reference Framework
the science of measuring the earth
Geodesy
the science of identifying and measuring specific locations on the earth
Surveying
slight non-spherical object of the size and shape of the earth
Spheroid
a mathematical model of the size and shape of the earth
Ellipsoid
a theoretical surface generally defined as mean sea level. Used as the basis for a vertical datum and as reference for a horizontal datum.
Geoid
a spheroid used as an (X,Y) reference to all points on the real globe
Horizontal Datum
level surface to which heights (elevation) are referenced
Vertical Datum
2 Types of Coodinate System
Global or Spherical Coordinate System
Projected Coordinate System
based on a map
projection, such as transverse Mercator, which
provide various mechanisms to project maps of the
earth’s spherical surface onto a two-dimensional
Cartesian coordinate plane.
Projected Coordinate System
System that uses such as longitude-latitude. These are often referred as Geographic Coordinate System
Global or Spherical Coordinate System
is a geodetic datum first defined in 1911 and is suitable
for use in Philippines - onshore
Luzon 1911
Luzon 1911 references the _______ and the
________.
origin is Fundamental point:
Clarke 1866 ellipsoid
Greenwich prime meridian.
Hinanggayon, Marinduque
is a homogeneous national network of geodetic control
points (GCPs), marked by concrete monuments or
mojons, that has been established using Global
Positioning System (GPS) technology – NAMRIA
PRS92 or the Philippine Reference System of 1992 i
Zone I 117° Zone II 119° Zone III 121° Zone IV 123° Zone V 125°
Zone I 117° E Area W of 118 E
Zone II 119° E Palawan and Calamian Islands
Zone III 121° E Luzon (except SE), Mindoro
Zone IV 123° E SE Luzon, W Mindanao
Zone V 125° E E Mindanao, Bohol, Samar
Single square cells • Each cell will have a value corresponding to its land cover type. • Represents features as a matrix of cells in continuous space.
Raster
Types of Data Model
Raster
Vector
are stored as individual X, Y coordinates or as individual column. Row cell entries in a grid
Points
are stored as a set of mathematically connected X, Y coordinates or as a set of connected grid cells
Lines
are stored as a set of mathematically connected X, Y coordinates defining the boundary or as a set of contiguous cells defining the interior
Areas
Those collected in digital format specifically for use in a GIS Project by direct measurement
Primary Sources
those reused from earlier studies or obtained from other systems
Secondary Sources
It is the measure of totality of
features.
Data Completeness
can be termed as the
degree of details that are displayed on a uniform
space
Data Precision:
This can be termed as the
discrepancy between the actual attributes value and
coded attribute value
Data Accuracy
can be termed as
the absence of conflicts in a particular database.
Data Consistency
means gathering
information about something (object) without
actually being in any contact with it.
Remote Sensing
Why Remote Sensing?
to see differences over time
to measure sizes, areas, depths, and heights; and in general
to acquire information that is difficult to acquire by other means
A __________ in orbit around the earth has a sensor
which scans the Earth’s surface measuring the
amount of light reflected/transmitted.
satellite
is one in which the satellite is always in
the same position with respect
to the rotating Earth
Geostationary Orbit
- An orbit that goes over
both the North and the South
Pole is called a ____________.
Polar orbit/Sun-Synchronous Orbit
A ________ is a device t hat measures a certain energy
level of the electromagnetic spectrum and converts it
into a signal which can be read by an instrument
Sensor
is generated by feature extraction from high
resolution stereo satellite imagery
DEM
uses inSAR which measures Earth’s elevation with two
antennas. In only a couple days, ______ has collected
one of the most accurate digital elevation models of
Earth.
SRTM
Shuttle Radar Topography Mission
is an active sensor that measures ground height. Using light from an airplane or helicopter platform, it measures the time it takes to bounce back to the sensor. From this, you can create Digital Surface Models which is useful in forestry
Light detection and Ranging (LiDAR)
Data to generate Digital Elevation Models (DEMs). This
radar mapping technology is an effective tool for
collecting data under challenging circumstances such as
cloud cover, extreme weather conditions, rugged terrain,
and remote locations.
IfSAR/InSAR
GIS Application
Groundwater Ground Hazard Regional Geology Mapping Fault line Mapping Earthquake Movement
Are satellites specifically designed for Earth
observation from orbit, similar to spy satellites but
intended for non-military uses such as
environmental monitoring, meteorology, map
making etc
Earth observation satellites
is an object-detection system that uses radio waves to
determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain.
• A radar system consists of a transmitter producing
electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the object(s).
RAdio Detection And Ranging
RAdio Direction And Ranging
Is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. These light pulses—combined with other data recorded by the airborne system— generate precise, three dimensional information about the shape of the Earth and its surface characteristics.
Light Detection and Ranging
Two types of LIDAR are
_____ LIDAR typically uses a near-infrared laser to
map the land
LIDAR uses water-penetrating green light to
also measure seafloor and riverbed elevations
Topographic
Bathymetric
Is helpful for exploring and mapping the ocean because sound waves travel farther in the water than do radar and light waves.
Sound Navigation and Ranging
emit an acoustic signal or pulse of
sound into the water. If an object is in the path of the sound pulse, the sound bounces off the object and returns an “echo” to the sonar transducer. If the transducer is equipped with the ability to receive signals, it measures the strength of the signal.
Active Sonar
are used primarily to detect noise from marine objects (such as submarines or ships) and marine animals like whales. it does not emit its own signal, which is an advantage for military vessels that do not want to be found or for scientific missions that concentrate on quietly “listening” to the ocean. Rather, it only detects sound waves coming towards it.
Passive Sonar
