Transcript Intro to Atmosphere - Downtown Magnets High School

Introduction to the
Atmosphere
Solar Radiation
• Seasons determined by earth’s tilt (23.5
deg)
• If Nor. Hem. tilted to Sun  summer.
Highest solar radiation
In The Air….
• 2 main gases: N and O
N = 78 %
O = 21 %
• 1 % left are trace gases 
CO2, CH4
• Divided into layers.
• Fxn: to protect Earth’s surface
from radiation & keep planet
warm.
st
1
layer…TROPOSPHERE
• We live here
• Weather occurs.
• 0-10/15 km up
• Go up  temp drops
Temperature Inversion
• Normal
conditions: cool
air on top, warm air
below.
• Temp Inversion:
cool air on bottom,
warm air on top
• Cold air heavy
traps pollutants
Case Study: London Smog 1952
• Death of 12,000.
• Cold fog in London  began burning
more coal to keep warm.
• Air poll. trapped by a thermal inversion
(cold air below, warm air on top).
London Smog 1952
London Smog 1952
Urban Heat Island
• Metro area where
temp is hotter in city
vs outside city.
• Caused by buildings
blocking cooler air
• Also by asphalt and
cement absorbing
heat during day and
releasing it at night.
Urban Heat Island
nd
2
layer: STRATOSPHERE
• Above troposphere.
• 10-50 km up
• Go up  increase in temp.
• Contains ozone!!
• Stratospheric Ozone: made up of 3
Oxygens, O3.
• Main fxn: absorb UV rays produced
from Sun.
• Acts as a shield to prevent exposure.
Purple = Low O3
Green = High O3
Mesosphere and Thermosphere
• 3rd Mesosphere:
above strat.,
coldest layer. 5080 km up. Go up
 temps fall.
• 4th
Thermosphere:
80-480 km up.
Go up  temps
rise.
Pauses
• Found in b/t layers; temps are constant.
• Tropopause: b/t troposphere and
stratosphere (jet stream)
Create a mnemonic to remember
the Earth’s atmosphere layers!
Write it down and then share
with your neighbor!
• Air pressure: differs in troposphere.
• Pressure  force exerted on a unit of area
of a surface.
• Movement of air from high to low pressure
areas  wind.
Wind and Ocean Current Direction
• Controlled by Earth’s
rotation (Coriolis
Effect).
• Objects are deflected
• No. Hem: right of
equator
• So. Hem: left of
equator
NASA/Goddard
Space Flight Center
Scientific
Visualization Studio
El Niño Conditions
• Trade winds relax; wind doesn’t move water to
Indonesia in West Pacific.
• Warm water accumulates in So. America
• Causes decline of upwelling which brings nutrients to
surface Death/movement of orgs in ocean.
• 3-8 yrs during winter
Chris Farley
What is La Niña Then?
• Opposite of El Niño: Cold air oscillations
• Usually happen after an El Niño year;
water is really cold in east Pacific and
needs to be reheated.
• Unusually cold ocean temps in Eastern
Eq. Pacific
California
Storms in East
Pacific, Lots of
Rain (Hotter
Water)
California
Migration of Tropical
Orgs (Water is warmer
now)
South
America
Massive
floods, mud
slides,
Fisheries
collapse (little
upwelling 
lack of
nutrients
South
Pacific
Typhoons,
Coral Bleaching
(Sensitive to
Heat)
Australia
EXTREME Drought in
East Pacific, dust
storms, fires