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Detection of Land Surface Changes and Environmental Impact Brought on by
Urban Development Using Remote Sensing Data
JongGyu Han
KIGAM, Gajeondong Yuseongku, Postal Code 305-350,
Daejeon, KOREA
jghan@kigam.re.kr
Abstract
In this paper, we use multi-temporal remote sensing
data to analyze the pattern of surface change of the city of
Shanghai and its neighborhoods brought on by the
sudden development of the city and analyze how the
surface change affects the change in surface temperature.
To detect the surface change, the study used the satellite
data of Landsat 3 MSS in 1979, Landsat 5 TM in 1989,
Landsat ETM+ in 2001. To analyze the surface change of
22 years, the study used each of the satellite data to make
the land surface maps, superimposed them together and
analyzed the quantitative data for the amount of the
surface change. We applied ISODATA unsupervised
classification algorithm to classify them and made error
matrix to verify the classification accuracy. The
classification accuracy for the land cover maps was
analyzed to be 93.01%, 90.44%, 88.23%, respectively.
We analyzed the amount of the surface between 1979 and
2001 to find the change of 20.40%. That corresponds to
the area of about 166,354ha. The rate of change in the
urban area was 245.25%. Hence the size of the urban
area increased more than two-folds during the period. To
analyze the change in the surface temperature due to the
change of the surface, we used Landsat thermal infrared
data photographed in August, 1989 and July, 2001 to
make the surface temperature distribution map. To
analyze the impact of the surface change on the surface
temperature, we superimposed the land cover map and
the surface temperature distribution map to find out the
change of the surface temperature according to land
cover type. The average surface area in 1989 and 2001
were 23.55. and 28.78. hence increased by about 5.
in 12 years. The difference in the temperature of the
urban area and the agricultural area was found to be
2.01. in August, 1989 and 2.38. in July, 2001, hence
the difference increased by 0.37. This result can be
seen to verify the increase in the surface temperature due
to urbanization. The increase in temperature due to
global warming can be one factor to this, but the change
in the material such as concrete, asphalt, and steel that
cover roads, buildings and industrial complex built due to
the sudden increase of the urban area seem to have a
bigger impacts.
1. Introduction
As the biophysical status of the surface of the earth,
the land cover is the basis of the most material and energy
transfer and of the transfer of the materials and energy
and the interaction between the geosphere and the
biosphere. The land surface change involved the variety
of organism, soil type, running water and the change in
the rate of deposition and the cause of it cannon be
understood without the knowledge about the change in
the usage of the land. Hence, it can be said that the usage
of the land and the surface change has a limited and
localized environmental implication and also related to
the global environment change process. Because of the
interconnected nature of the natural environment
components, a direct impact on one component can have
an indirect impact on another component[1].
The urbanization, which is the change in the surface
type due to the popular increase and the economic
development, is historically an important pattern in the
change of the land cover and has the biggest influence on
the climate. The urban area, which is covered by
buildings, roads, and impervious materials, absorbs high
amount of solar radiation and has a higher heat value and
conductivity. As a result, the heat is stored during the day
and released during the night. The difference of
temperature between the urban area and the island area is
not very big - on average, about 1·. But when the urban,
geographical, meteorological conditions meet that of
generation of urban heat island effect, the difference can
increase to several centigrades.
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