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Environmental Sciences Course
Air Pollution and Climate Change
Dr.-Eng. Hasan Hamouda
Eng. Osama Othman
Outline
Atmosphere and Climate
Climate Change
- El Nino
- Human Causes
Climate and Pollution
- Kinds of Pollution
- Sources
- Transport
Effects of Air Pollution
Air Pollution Control
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
2
ATMOSPHERE AND CLIMATE
Weather - A description of short-term physical
conditions of the atmosphere.
Climate - A description of the long-term weather
pattern in a particular area.
Weather and climate are primary
determinants of biomes and ecosystem
distribution.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
3
Troposphere
Troposphere
- Ranges in depth from 18 km over the equator to 5
km over the poles.
- Air circulates in convection currents.
- Air temperature drops rapidly with increasing
altitude
- Contains 75% of total air mass.
Tropopause: Transition boundary limits mixing
between the troposphere and upper zones.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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A Layered Envelope
Stratosphere
- Extends from troposphere to about 50 km.
- Similar composition to Troposphere, but much more
dilute.
- Temperature increases with altitude.
- Fraction of water vapor is 1000x less and ozone is
1000x more than in the troposphere.
- Relatively calm
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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A Layered Envelope
Mesosphere
-Middle Layer.
-Minimum temperature is about - 80o C.
Thermosphere
- Ionized gases and high temperatures.
- Ionosphere - Lower Thermosphere
- Aurora borealis (northern lights)
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
6
Atmospheric Temperature
Changes
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Energy & Greenhouse Effect
Solar Radiation
- Solar energy not evenly distributed over the
globe.
- Of solar energy reaching outer atmosphere:
25% reflected
25% absorbed
50% reaches earth’s surface
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Solar Radiation
Visible light: passes through atmosphere undiminished.
Ultraviolet light: is absorbed by ozone in the
stratosphere.
Infrared radiation: is absorbed by carbon dioxide and
water in the troposphere.
- Albedo - Reflectivity
- Fresh clean snow 90%
- Dark soil 3%
- Net average of earth 30%
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Solar Radiation
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Solar Radiation
Most solar energy reaching the earth is visible light.
- Energy remitted by the earth is mainly infrared
radiation ( heat energy).
- Longer wavelengths are absorbed in the
- lower atmosphere, trapping heat close to
the earth’s surface.
Greenhouse Effect: Increasing atmospheric
CO2 due to human activities appears to be
causing global warming.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
11
Convection & Atmospheric
Pressure
- Water vapor contains a large amount of energy stored
as latent heat.
- Evaporation converts solar energy into latent heat
stored in evaporated water.
- Uneven heating produces pressure differences that
cause wind, rain, and storms (weather).
- Vertical convection cells circulate air masses between
warm and cooler latitudes.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Why Does It Rain ?
Releasing latent heat causes air to rise, cool, and lose
more water vapor.
- Rising, expanding air creates an area of relatively
high pressure at the top of the convection
column.
- Air flows out of high-pressure zone
towards areas of low-pressure, where
cool, dry air is subsiding.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Why Does It Rain ?
- Subsiding air is compressed as it approaches the
earth’s surface where it piles up and creates an area
of high pressure at the surface.
- Air flows out of this region back towards low
pressure, closing the cycle.
If condensation nuclei are present, or if
temperatures are low enough, condensation will
lead to precipitation.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
14
Convection Currents
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Coriolis Effect & Jet Streams
- Surface flows do not move straight North and South,
but are deflected due to Coriolis Effect.
- Major zones of subsidence occur at about 30o north
and south latitude.
- Where dry, subsiding air falls on continents, it
creates broad, subtropical desert regions.
- Winds directly under regions of
subsiding air are often light and variable
- Horse latitudes
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Convection Cells &
Prevailing Winds
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Jet Streams
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Seasonal Winds
Monsoon - Seasonal reversal of wind patterns caused
by differential heating and cooling rates
of oceans and continents.
- Most prevalent in tropical countries where large
land area is cut off from continental air masses
by mountain ranges and surrounded by a large
volume of water.
University Of Palestine UNI
3316 Dr. Hasan Hamouda Eng. Osama Othman
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Monsoon
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3316 Dr. Hasan Hamouda Eng. Osama Othman
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