Transcript Energy Transfer and Weather powerpoint

Energy from the Sun
that reaches Earth by
waves through space
Types of solar radiation:
•Visible light range of the
ultraviolet spectrum
•Infrared radiation
•Ultraviolet radiation
Visible light range
of the
ultraviolet spectrum
Cones in our eyes are receivers for these tiny
visible light waves.
The Sun is a natural source for visible light waves
and our eyes see the reflection of this sunlight off
the objects around us.
The color of an object that we see is the color of
light reflected.
All other colors are absorbed.
A visible light picture (left) and an infrared picture (right) of two cups. One cup
contains cold water, while the other contains hot water. In the visible light picture we
cannot tell, just by looking, which cup is holding cold water and which is holding hot
water. In the infrared image, we can clearly "see" the glow from the hot water in the
cup to the left and the dark, colder water in the cup to the right. If we had infrared
eyes, we could tell if an object was hot or cold without having to touch it.
http://coolcosmos.ipac.caltech.edu/cosmic_kids/learn_ir/index.html
Above are infrared images of a warm-blooded dog (left) and of a warmblooded human holding a cold-blooded caterpillar (right). Warm-blooded
animals, like the dog shown above, make their own heat. In the infrared
picture you can see how the dog's fur keeps some of this heat from escaping,
keeping the dog warm. Insects are cold-blooded, which means that they
cannot make their own body heat. Instead they take on the temperature of
their surroundings. The cold-blooded caterpillar appears very dark (cool) in
the infrared compared to the warm-blooded human who is holding it. Notice
how the caterpillar is at about the same temperature as the surrounding air.
Another interesting fact about infrared light is that it can travel through thick
smoke, dust or fog, and even some materials.
http://coolcosmos.ipac.caltech.edu/cosmic_kids/learn_ir/index.html
Infrared radiationlonger waves that warm the Earth
Although infrared
radiation is not
visible, humans
can sense it - as
heat. Put your
hand next to a
hot oven if you
want to
experience
infrared radiation
"first-hand!
shorter waves than visible light waves
that interact with skin to cause
sunburn
What
effect
does solar
radiation
have on
Earth’s
oceans?
It warms the water.
Plants use the
sun’s energy
through
photosynthesis
What energy
changes take
place during
photosynthesis?
Plants change light energy from the sun
into chemical energy
Animals use the sun’s energy in the
food chain
Humans
use the
sun’s
energy to
run
machines
with fossil
fuel
Humans
use the
sun’s
energy
for
electricity
Earth’s temperatures are affected by:
•Where the sunlight hits the Earth
•Interaction with the atmosphere
Landforms and oceans absorb
51% of solar radiation
Earth, in turn, gives off infrared
radiation
Clouds and gasses absorb this
heat and send it back to
Earth’s surface
The way in which Earth’s atmosphere traps
and stores energy near the Earth’s surface
Why is the sky blue?
Because of:
• Visible light
• Each wave of color has a
different length
• Red longest
• Blue shortest
• Particles in the atmosphere
absorb and scatter blue waves
OR………………………
Sunlight collides with air,
scatters blue wavelengths.
Caused by the
tilting of the
hemispheres
toward the sun
• Driven by solar radiation
• Water absorbs solar radiation
• Energy causes water to evaporate and turn to
water vapor. This is less dense than water and
it rises.
• Water vapor condenses around dust particles
• Turns to tiny droplets of water that become
clouds
• Fall as rain or snow
• Runs off or becomes groundwater
• Plants absorb water
• It goes to leaves and absorbs solar energy
• Evaporates
• Cycle continues
Oceans
• 97% of Earth’s water is in oceans
• Oceans cover 70% of Earth’s surface
The waters of the oceans move in currents.
Warm water flows from Equator to poles.
Cooler water flows to the Equator.
Convection, tides and winds affect the
movement.
Convection Current
• Cold water in the
Atlantic sinks under
warmer water then
moves south, circles
Antarctica, then moves
northward.
• Water is heated by
thermal vents in the
ocean floor. It rises to
the surface, loses heat
energy to the
atmosphere and cools.
• This cool water sinks
and the cycle continues.
Surface Currents
• California Current
• Takes cold water from the North Pole, flows
south and helps keep weather cooler.
• Gulf Stream
• Picks up warm weather from the Equator
and flows northeast along the east coast.
California
Current
Gulf Stream
Coastal
Eddies
•Run in
opposite
direction
from a
main
current
•Source
of
nutrients
for sea
life
Thermal gradient
A gradual increase or decrease in temperature
over a distance
Example- from the North Pole to the Equator
Air pressure
•Air pressure is the force exerted on you by
the weight of tiny particles of air (air
molecules).
•Differences in air pressure are caused by
uneven heating of Earth’s surface.
•http://kids.earth.nasa.gov/archive/
air_pressure/spin.html
•http://kids.earth.nasa.gov/archive/
air_pressure/barometer.html
Wind
•Hot air rises
•Leaves an area of
low pressure
•As it moves, it
cools
•Molecules get
closer together
and the pressure
increases
•Air moves from
areas of high
pressure to low
pressure
A difference in air
pressure is what
causes the wind
to blow.
Wind is simply air
moving from a
place of high air
pressure to a
place of low air
pressure.
The greater the
difference in air
pressure, the
stronger the
winds.
Convection
Air Currents
are affected
by
•Uneven
heating of
Earth’s
surface
•Geography
of the land
•Earth’s
rotation
Coriolis Effect
•Change in direction of a freely moving object,
caused by the Earth’s rotation
•Responsible for circular motion of many
weather patterns
•Earth’s rotation
•http://www.baesi.org/TRG/coriolis/CORIOLIS.
MOV
•Rock so hot that it can flow
like taffy or syrup
•Heat from the Earth’s core
(12,000ºF) causes the rocks
to heat those above them
•This heat moves by
convection
•When the hot rock reaches the
lithosphere, it spreads out.
•The rock cools, then
sinks back down.
•The cycle continues.
•These currents can force the plates to
move, causing mountains to form,
volcanoes to erupt, and continents to
change shape.
Unlike climate,
weather can change
quickly.
The exchange of
energy between air
and ocean currents is
a cause of this
change.
Weather Changes
•Thunderstorms
•Hurricanes
•Waterspouts
•Atmospheric Edd
Air masses
•Maritime- over water
•Continental- over land
In California
•Polar maritime
•Tropical maritime
Air masses cause a change in air
pressure which leads to a change in
weather.
Humidity is the
amount of water
vapor in the air
Relative Humidity
The ratio of the actual amount of water vapor in
air to the possible amount that the air could
contain. Warm air masses can hold more than
cold.
Fronts
•Cold front- cold air mass moves toward an
area of warmer air usually causes steady rain
•Warm front- warm air mass moves toward an
area of colder air, usually causes heavy rain
•Stationary front- when two air masses meet
and are not moving, usually causes a long
period of precipitation