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The Influence Of Global Warming On Desertification
Department of Civil and Environment System EngineeringUniversity of Incheon, South Korea
2200919 박 치 만
Contents
Background and Purpose of Study
Definition of Desertification
Mechanism of Desertification
Summary
Air Environment Engineering 2
Background & Purpose of Study
Air Environment Engineering 3
Average temp. of the earth goes up due to global warming gas like car-bon.
The climate change become bigger.
Extremely high temperature or
heavy rain.
Arid area expends.(Desertification)
Definition of Desertification
The phenomenon that arid land is changed into desert by various causes like climate change and human activity
Air Environment Engineering 4
Mechanism Of Desertification
Drought
Deserti-fication
Albedo↑
De-scend-
ing cur-rent
Global
Warming
Air Environment Engineering 8
The Damage of Global Warming
Increase the number of extremely hot and cold days Temperature rising accelerates hydrologic cycle, so a drought and a flood have become more frequently, extremely.
Air Environment Engineering 9
Albedo Rising Albedo - Overall average reflection coefficient of an object
Air Environment Engineering 10
Surface Albedo(%)
Desert(sand) 30~60
Crops(Green) 5~25
Forest(Green) 5~10
Grassy plain(Green)
5~25
Farm land 14~17
Soil(Dark) 5~15
Soil(Bright) 25~30
Desert emits energy as long wave radiation more than forest and crops, due to its high temperature and albedo.
Temperature of air over desert goes down, and then descending current begin.
Ascending & Descending air current
High pressure area is clear, because air is compressed as it drops.
Low pressure area is cloud, because air swells as it ascends.
Air Environment Engineering 11
Summary 1
Desert Surface( Albedo: 30~60%)
Upper Air(Emitting radiation energy >Absorbing energy )
① Solar radiation
100
③ Temperature
④ Descending air current
70
60
⑥ Extension of Desert
⑤ No rain , no cloud = clear
② Earth radiation
Air Environment Engineering 12
Summary 2
During descending air current, volume of air de-crease, so temp. of air goes up due to adiabatic change.
Owing to continued descending air current, desert isn’t rain, more and more it becomes arid and expands.
Air Environment Engineering 13
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