Transcript Interactions of Solar Energy with Land and Air

Interactions of Solar Energy
with Land and Air
Weather Dynamics
Science 10
Heating Dry Land
• If you take 1 gram and sand and 1 gram of
water and heat them up, the sand will warm
up 5 times as fast as the water. Shocked? I
think so!
• You have already learned that water’s high
specific heat capacity has a large role to
play in this discrepancy.
• Water takes much more energy to heat up
and therefore the sand is able to get
warmer, quicker 
Heating Dry Land
• A second reason for drastic change in temperatures is
that unlike water, all the radiant light that hits the sand
is absorbed over only the top few centimetres.
• Since light cannot penetrate through the sand, the
only way for sand which does not receive light to
warm up is through conduction (touching other sand
granuoles that were lit).
• Water’s translucency allows light to penetrate further
and spread out over a wider area, making it “cooler”.
Heating the Air
• All 3 ways that heat transfers in an environment are
used to heat the air. Can you think of how each one
plays a part?
• Conduction: Energetic molecules of land
collide with cooler air molecules close to the
surface, giving the molecules in the air some
energy. This heats the air.
• Convection: These warmed air molecules
become less dense and rise, allowing cooler
air molecules to reach the surface and allow
conduction to warm them as well.
• Radiation: The sun’s solar radiation warms
the air molecules as well.
Layers of our Atmosphere
• Our atmosphere has Layers!!!
The 4 Atmospheric Layers
• Although there are no defining lines between
parts, scientists have divided our
atmosphere up into 4 layers.
• Each part is classified by its distance from
the Earth’s surface, as well as common
temperature trends in each of the regions.
• Drastic changes in temperature (either
increasing or decreasing) warranty a new
layer with a new name! 
Layer 1: Troposphere
• Located about 10km from the Earth’s
surface.
• All weather that occurs, occurs in the
troposphere.
• Unlike Earth, who’s temperature flucates on
a daily basis, the temperature in the
troposphere remains fairly constant at -57°C.
Layer 2: Stratosphere
• From the troposphere to about 50km from
the Earth’s surface.
• This zone is classified as a different zone
because the temperature actually increases
here (Out in space the temperature goes up?
Huh?).
• The reason for the sudden temperature
increase is the presence of ozone. (Your
ozone layer is found here!)
Ozone
• The ozone layer seperates the troposphere
and the stratosphere.
• Ozone absorbs ultraviolet light from the
Sun
• This causes the temperature to rise in the
stratosphere.
• If the ozone layer was not present, the
amount of ultraviolet radiation that reached
the Earth’s surface would be hazardous to all
living creatures.
• And so, the ozone layer makes life on Earth
possible 
Reviewski – Answer On your Own
• Give me 1 example of conduction,
convection, and radiation.
• What is specific heat capacity? Heat of
vaporization? Heat of fusion?
• What is humidity?
• Why does land heat up quicker than water?
• What is the first layer of the atmosphere?
What happens here?
• What is the second layer of the atmosphere?
What happens here?
Layer 3: Mesosphere
• Between 50 and 60 km above sea level, the
temperature levels off again (like in the
troposphere) at about -2°C.
• This area marks the top of the stratosphere.
• The next layer, the mesosphere extends
from around 60km from the Earth’s surface
to about 90 to 100 km.
Layer 3: Mesosphere
• The mesosphere is defined by another
sudden drop in temperature.
• Here the temperature levels off to a frigid 90°C to -100°C. BrrrRRRrrr!
• Meteors from outer space often penetrate up
to this layer of the atmosphere, but then burn
up due to air friction.
Layer 4: Thermosphere
• At an altitude of 100km, the temperature
begins to rise and becomes much, much
higher than any other level.
• Since this region has such a high
temperature, scientists called it the
thermosphere.
Layer 4: Thermosphere
• Meteorologists discovered that oxygen
molecules in this layer absorb the very high
energy ultraviolet light, accounting for the
drastic increase in temperature.
• At 150km, the temperature reaches 180°C.
• At 500km, the temperature hits a sweltering
600°C!
The Ionosphere
• In between the mesosphere and the
thermosphere is a layer of charged particles
called the ionosphere.
• As already mentioned, the thermosphere
warms due to atoms absorbing ultraviolet
light.
• The absorption of this high energy ultraviolet
light cause electrons to be ejected from
atoms, creating ions.
The Ionosphere
• The charged ions have a direct effect on radio and
satellite communications.
• The ionosphere bends radio waves, making it
possible to pick up signals at great distances from a
radio transmitter.
• This bending of waves also makes it impossible to
use radio waves to communicate with satellites, since
they waves cannot pass the ionosphere to reach the
satellites.
• We use microwaves (which are small enough to pass
through the ionosphere to communicate with
satellites).
1. Troposphere
Ozone
So what is the order of the layers of
Stratosphere
the atmosphere? Can you get
Mesosphere
them
all?
Ionosphere
Thermosphere
Assignment
• Draw a diagram of a section of the Earth.
• In this show each of the layers of the earth’s
atmosphere (include the ozone and the
ionosphere).
• For each give:
• the distance from the Earth’s surface
• the temperature (if not exact, give the range
that the temperature’s may go to).
• draw a picture of what happens there (for
example weather in the troposphere).
•
Fully colour and label your diagram.
Thermosphere
• The reason
this only
the North
thermosphere
is occurs
also theatlocation
of and
the
South
poles display
is due to
Earth’sand
magnetic
magnificent
ofthe
northern
southern
field
gases
at the poles, and no
lightspulling
called in
the
aurora.
else.of lights is created by clusters of
• where
This array
charged particles with extremely high energy
the
Sun.which get excited only enter the
• from
These
gases
at the
poles where
thesolar
magnetic
• atmosphere
These particles
(sometimes
called
fields
inward
wind),pull
collide
withgases passing on energy
and exciting these gases.
• The excess energy from the collisions is
shown in the lights we see in the sky.
Earth’s Magnetic Field
• The magnetic field around Earth exists
because of electrical currents in the Earth’s
molten metallic core are rotating.
• The magnetic field shields the Earth from
solar winds of the sun.
• Solar wind are highly energetic charged
particles from the Sun which would be
potentially harmful to life on Earth if they
were able to enter the atmosphere (Thank
You Mr. Magnetic Field!)
Greenhouse Gases
• As you already learned, oxygen in the
thermosphere absorbs a lot of ultraviolet
light.
• What do the other gases in our atmosphere
do? What is the “Greenhouse Effect?”
• Greenhouse gases – carbon dioxide,
methane, dinitrogen oxide, and CFCs.
Greenhouse Gases
• There is very little absorption of any other
solar radiation by gases (Remember what
solar radiation included).
• But! The atmosphere (specifically Carbon
Dioxide and Water Vapour) absorb the longer
wavelength re-radiation (radiation that was
previously absorbed and released).
• Huh? What does this mean? Good question.
Greenhouse Gases
• The other greenhouse gases (like carbon dioxide) trap
the infrared radiation released from Earth and warms
the atmosphere before it escapes into space.
• If there were no greenhouse gases at all, Earth’s
average temperature would be 35°C lower.
• Since plants could not grow in these conditions,
greenhouse gases are necessary for life on Earth.
• So these gases are good! Why then are scientists
concerned about the “Greenhouse Effect”?
Greenhouse Gases
• The concentration of carbon dioxide in the
atmosphere is critical.
• Too little – Earth would be too cold.
• Too much – Earth’s temperatures would rise
to a potentially dangerous extent.
• How do you think an increase in
temperatures might affect life on Earth?
• How would it affect the weather?
What Should I Know?
• Why land heats slower than water.
• How air heats up using all 3 types of transfer.
• The 4 layers of the atmosphere.
• How the aurora is formed.
• What is the magnetic field used for.
• How greenhouse gases affect Earth
• Why the Greenhouse Gas effect is bad.
Do You Understand?
• Why does land heat up faster than water?
Does all of the land heat up? Explain.
• Explain the role of conduction in the heating
of air.
• Why is it necessary to use microwaves to
send signals to and from communication
satellites?
• What causes the aurora?
• What do greenhouse gases do? Are they
bad?