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Chapter 3, THE ATMOSPHERE

Composition

Vertical Structure

Depletion of the Ozone Layer

Air Pollution

Weather and Climate

Coriolis effect

p. 6/7The Environmental spheres

Hydrosphere

Lithosphere Biosphere

Water

Land Green stuff

Air

Atmosphere

•It is an “ocean of air” ( 10,000 km or 6,000 mi above the surface) surrounding Earth, held to Earth by the force of gravity •=> dynamic movements of currents and circulation of air which creates the changing conditions, the weather.

98% of its mass is concentrated at very low altitudes, within 26 km or 16 mi of sea level. Pressure?

Why the Atmosphere is essential to our life?

• The Atmosphere is a thin film of air which serves as insulator, maintaining the temperatures on Earth.

* Without atmosphere, Earth would experience t extremes as 200 deg. C (500 deg. F) between day and night.

• The Atmosphere serves as a shield blocking out much of the sun’s UV radiation and protecting us from meteor showers. What are the temperatures on the Moon?

Weather and Climate

• Weather refers to short- run atmospheric conditions for a given time in a specific area (temperature, humidity, clouds, precipitation, wind, storms, etc.)

• Climate- weather conditions over a long period of time ( at least three decades)

• Elements of weather and climate: temperature, moisture content, pressure and wind

• The Controls: latitude, distribution of land and water, general circulation of the atmosphere, altitude, topographic barriers, storms

p. 50

An inert gas

Permanent Gases- min effect on weather & climate

• Nitrogen- 78%, added to the air by the decay and burning of organic matter, volcanic eruptions, chemical breakdown of rocks; it is removed by some biological processes and rain or snow.

• Oxygen- 21%, produced by vegetation, removed by organic and in organic processes

• Argon- 0.037%- an inert gas

Variable Gases- significant influence on weather & climate

CO2- 0.037%- an increased burning of fossil fuels for the last century

Ozone- in the ozone layer- an absorber of ultraviolet solar radiation

Water Vapor- invisible, in moist surface areas (tropical oceans), deserts?

Particulates or Aerosols- solid and liquid particles- dust, ash, smoke, soil, ice, water

Ozonosphere- between 9-30 miles

Vertical layers of the Atmosphere• 1. Troposphere- water vapors,

gases and small particles from pollution. Temperature decreases with increased altitude.

• Normal Lapse Rate- 6.5 deg. C per 1000m (3.6 deg.F/1000ft)

• 2. Stratosphere- constant temperature in the lower part

• (- 57 deg. C, or -70 deg. F)• * Ozone layer- it absorbs the UV

radiation- release of heat, increase of temperatures in the upper parts of the stratosphere. Water=ice clouds

• 3. Mesosphere- t tend to drop• 4. Thermosphere- t increases

Temperature (Fº)

96

21

Ozonosphere lies between

15-50km (9-30 mi) above the

surface.

It filters the UV energy from

the sun.

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Ozone hole/depletion over Antarctica

Ozone in the upper atmosphere is destroyed by chemical reaction to chlorofluorocarbons (CFCs) and other gases- products of pollution. On the

poles- no big cities but :(1) the circulation patterns move from the tropics the polluted air to the

poles and back.(2) Austral winter- S. Pole- dark and cold, ozone is trapped with pollutants;

Spring- the solar radiation dissolves the vortex and the ozone.(3) Ice clouds in the stratosphere create ozone- destructive reaction.

Growing Ozone Hole over Antarctica

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Destruction of

Text pg. 21-24, 95-6, 290-1

Increased skin cancers

CO2 & water vapor (greenhouse gases) impede the escape of long-wave R by absorbing it and then

radiating it back to Earth.

NEWSWEEK, 8/20/01

Maureen Reagan dies at age 60

LITTLE OZONE ANNIE

Hot sunny, 105° F

Air Pollution and the Industrial Revolution

• Primary pollutants- released directly into the air: particulates (aerosols), smoke, dust, salt, sulfur and nitrogen compounds, carbon oxides

• Secondary pollutants- not released directly into the air (from chemical reactions): photochemical smog- A number of gases react to UV radiation in strong sunlight

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Pinatubo erupting

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BURNING OF FOSSIL FUELS

One degree Fahrenheit rise in temp. record of the entire earth’s surface during the 20th Century

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Equatorial Rainforest

Thermal Power Plant burning fossil fuelscoal

oilnatural gas

We are evaporating our coal mines into the air” --Svante Arhenius

12/5/95

HIGHEST GREENHOUSE GAS EMISSIONS, 1989

This is your planet on greenhouse gases

1/17/98

Jan., Feb. ’00 hottest on record

contrails

Heat wave deaths in Chicago Midwest = 529 but as high as 739

= 1,177 diedAverag

e number of heat deaths per year is…

175

O’Hare max. temp.104ºF, 2nd highest on record, had a heat index of maxing out at 119ºF. Dew point temps. were very high in the 70’s and 80’s . Midway, another airport, reached 106ºF with a heat index of 125ºF.

8/1/99 Bags of ice help cool chickens during a show at a county fair in Nebraska.

7/31/99 HEAT STRICKEN. A police officer gives water to Mary Prowls, 81, after he discovered her overcome by heat in her home.

Heat Wave, 1999

Deaths since 7/19 93

8/1191, 80 in Illinois

LA has 20 days over 90 F Chicago has 21 days

Heat deaths: Chirac pledges action CNN Thursday, August 21,

2003

PARIS, France—French President Jacques Chirac has promised to remedy defects in his country’s health service in the wake of the heat wave that killed thousands of mainly elderly people.

The French funeral directors association said 10 418 had died during the first three weeks of August. The projected death toll for the month would be 13 632.

Temporary, air conditioned morgue

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Gaspard Gustave de Coriolis, 1792-1843

Coriolis Effect

Ch. 5, p. 142

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cold

cold

warm

warm

Cold Labrador Current

warm