satellites have had a very well performance during their missions, expect for
Landsat 6 (USGS 2013a, b, c, d, e, f). To continue the mission of Landsat Project
of observing land-surface information the Landsat 8 with providing higher quality
data was recently launched on February 11, 2013 (USGS 2013a, b, c, d, e, f).
With technologies development, sensors onboard Landsat satellites have been
improved as well. Spectral and spatial information retrieved from USGS (2013a, b,
c, d, e, f) of each Landsat sensor are specified in Table 4.1. Landsat Multispectral
Scanner (MSS) was the primary sensor placed on Landsat 1, 2, and 3. MSS images
have four multispectral bands from green to near-infrared (IR) with 80 m resolution
and one thermal band with 240 m resolution only onboard Landsat 3. Thematic
Mapper (TM) sensors were placed on Landsat 4 and 5 with two added shortwave
infrared (SWIR) and one thermal band. Resolutions have been increased to 30 m for
visible and infrared bands and to 120 m for thermal band. Enhanced Thematic
Mapper Plus (ETM+) onboard Landsat 7 has one more panchromatic band in 15 m
resolution; and thermal band increased to 60 m resolution. As for the newly
launched Landsat 8, Operational Land Imager (OLI) sensor has eight spectral
bands in 30 m resolution. In OLI the following bands have been added (a) one
deep blue band and one cirrus band, and (b) one panchromatic band in 15 m
resolution. In addition, the Thermal Infrared Sensor (TIRS) has two thermal
bands with 100 m resolution (USGS 2013a, b, c, d, e, f).
4.2.2 Change Detection Methods
As Singh (1989) defined, “change detection is the process of identifying differences
in the state of an object or phenomenon by observing it at different times”. Changes
can be detected because of the radiance values of the objects and also change in
LULC alterations (Singh 1989). To monitor landscape changes effectively by using
remote sensing techniques, a variety of change detection methods have been
Fig. 4.1 Time scale of several remote sensing systems (Source: Patino and Duque 2013)
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A. Fu et al.
Landsat 6 (USGS 2013a, b, c, d, e, f). To continue the mission of Landsat Project
of observing land-surface information the Landsat 8 with providing higher quality
data was recently launched on February 11, 2013 (USGS 2013a, b, c, d, e, f).
With technologies development, sensors onboard Landsat satellites have been
improved as well. Spectral and spatial information retrieved from USGS (2013a, b,
c, d, e, f) of each Landsat sensor are specified in Table 4.1. Landsat Multispectral
Scanner (MSS) was the primary sensor placed on Landsat 1, 2, and 3. MSS images
have four multispectral bands from green to near-infrared (IR) with 80 m resolution
and one thermal band with 240 m resolution only onboard Landsat 3. Thematic
Mapper (TM) sensors were placed on Landsat 4 and 5 with two added shortwave
infrared (SWIR) and one thermal band. Resolutions have been increased to 30 m for
visible and infrared bands and to 120 m for thermal band. Enhanced Thematic
Mapper Plus (ETM+) onboard Landsat 7 has one more panchromatic band in 15 m
resolution; and thermal band increased to 60 m resolution. As for the newly
launched Landsat 8, Operational Land Imager (OLI) sensor has eight spectral
bands in 30 m resolution. In OLI the following bands have been added (a) one
deep blue band and one cirrus band, and (b) one panchromatic band in 15 m
resolution. In addition, the Thermal Infrared Sensor (TIRS) has two thermal
bands with 100 m resolution (USGS 2013a, b, c, d, e, f).
4.2.2 Change Detection Methods
As Singh (1989) defined, “change detection is the process of identifying differences
in the state of an object or phenomenon by observing it at different times”. Changes
can be detected because of the radiance values of the objects and also change in
LULC alterations (Singh 1989). To monitor landscape changes effectively by using
remote sensing techniques, a variety of change detection methods have been
Fig. 4.1 Time scale of several remote sensing systems (Source: Patino and Duque 2013)
66
A. Fu et al.