Aim: How does the Atmosphere on
Earth support life?
Do Now: In your notes, describe what
you think the atmosphere does for us?
I. Atmosphere (atm) Composition
• Made up of 4 layers (troposphere, stratosphere,
mesosphere and thermosphere)
- nitrogen and Oxygen make up 99% of the
gases in the atmosphere today Page 1 ESRT
What is the source of water
vapor in the atmosphere?
A. Water Vapor:
• oceans are the source
• Absorbs/trap heat (from earth & sun)
• makes the air lighter (less dense)
Altitude (km)
ESRT p.14
Describe the relationship
seen in the graph.
B. Dust Particles:
- any solid that can float in the air ( dust,
salt, ash, organics)
- helps make clouds (condensation nuclei)
- In large quantities,
these particles block out
the heat and light from
the sun.
What might be an effect of
blocking out light and heat
from the sun? Has this
happened before?
Mt. St. Helens Eruption, 1980
Mt. St. Helens Eruption Washington, 1980
Mt. Eyjafjallajökull Eruption Iceland, 2010
C. Ozone: (O3)
- found in the stratosphere.
- poisonous to people.
- filters harmful ultra-violet
rays (UV) from the sun.
- depleted (destroyed) by CFC’s
(chloroflorocarbons). These are
found in aerosol cans and
refrigerants.
II. Human Influence on the Atmosphere:
- Emissions from cars and factories account
for nearly half the pollutants by weight in
the atmosphere.
Where does the other half come from?
III. Atmosphere and Temperature
- Perfect distance from the sun!
- Water vapor and CO2 in the atmosphere
traps heat and keeps our planet warm.
150 million kilometers
Closure:
In your notes, answer the following questions;
1)How can humans decrease their negative
influence on the atmosphere?
2)Are there positive influences that people
have on the atmosphere?
Someone said there is a hole in the Ozone
Each winter as temperatures drop, ozone over southern pole
is “thinned” rapidly and severely. This depleted region is known
as the “ozone hole”. As temperatures begin to warm up, the
ozone begins to build up once again.
Ozone measurement
for September 2013
Ozone measurement
for March 30th 2014
DO
NOT
COPY