Transcript Ozone layer

Chapter
3,
THE ATMOSPHERE
Composition
Vertical Structure
Depletion of the Ozone Layer
Air Pollution
Weather and Climate
Coriolis effect
Page 49
The Environmental spheres
Air
p. 6/7
Hydrosphere
Atmosphere
Water
Biosphere
Lithosphere
Land
Green
stuff
•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
96
Temperature (Fº)
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 fuels
coal
oil
natural gas
We are evaporating our coal mines into the air” --Svante Arhenius
12/5/95
HIGHEST GREENHOUSE GAS EMISSIONS,
1989
Jan., Feb. ’00
hottest on record
This is your planet on greenhouse gases
1/17/98
contrails
Heat wave deaths in Chicago
= 529 but as high as 739
Average
number
of
heat
deaths
per year
is…
175
Midwest
= 1,177
died
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.
7/31/99 HEAT STRICKEN.
A police officer gives water to Mary
Prowls, 81, after he discovered her
overcome by heat in her home.
LA has 20 days over 90 F Chicago has 21 days
8/1/99 Bags of ice
help cool chickens
during a show at a
county fair in
Nebraska.
Heat Wave, 1999
Deaths since
93
191, 80
Illinois
7/19
8/1
in
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
Coriolis Effect
Gaspard
Gustave de
Coriolis,
1792-1843
p.63
Ch. 5, p. 142
62
cold
warm
warm
cold
Cold
Labrador
Current
warm