Page 49 Chapter 3, THE ATMOSPHERE Composition Vertical Structure Depletion of the Ozone Layer Air Pollution Weather and Climate Coriolis effect
Page 49
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.
57
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
47
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
59
Pinatubo erupting
47
BURNING OF FOSSIL FUELS
One degree Fahrenheit rise in temp. record of the entire earth’s surface during the 20th Century
72
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
p.63
Gaspard Gustave de Coriolis, 1792-1843
Coriolis Effect
Ch. 5, p. 142
62
cold
cold
warm
warm
Cold Labrador Current
warm