Energy Exchange in the Atmosphere

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Energy Exchange in the Atmosphere
Weather

• ____________ - the state of the atmosphere at a
  given time and place.
• ____________ - the study of the entire atmosphere
  including its weather.
• Atmospheric variables include -
  __________________________________________________
  ____________________________________

Meteorology
Temperature,moisture, air pressure,wind,
and atmospheric transparency
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Energy Transfer in the Atmosphere
Water cools, becomes more dense and sinks

• 1.__________ - the transfer of heat energy by
  movements of liquids and gases (fluids)
• Movements are caused by differences in densities
  in the fluids
• Heat is carried by
• __________________________
• (_____________________)

convection
Convection currents
Convection cell
Heated water becomes less dense and rises
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conduction
2. _______________ - transferring heat by
touching an object - i.e. pan on stove,
air on radiator 3. _______________ - the
transfer of electromagnetic energy
through space. - heat emanating from a
body as wavelengths of energy.
radiation
Look at page 14 in the ESRT.
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What controls heating and cooling?
1. Color
Dark heat faster . Because they absorb energy
faster
2. Texture
Rough heats faster . Because more surface area
3. Specific Heat
(Found in Ref. Tables)
Large number (water)
Heats/cools slowly.needs a large amount of
energy to change temp.
Small number (basalt)
Heats/cools fast.needs a small amount of energy
to change temp.
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B. Heat Balance
radiation

• energy enters and leaves Earth by
  __________________
• ___________ incoming solar radiation
• Energy that reaches the atmosphere
• reflected back to space
• absorbed
• absorbed by water vapor, clouds, ozone,
  and dust
• absorbed by surface
• of energy is radiated back by surface.
• of energy is transferred to atmosphere
  by
  conduction and convection.

Insolation
Current satellite image
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70
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51
21
30
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• Greenhouse effect __________________ of
  energy from the sun passes through the gases of
  the atmosphere but the _______________________
  given off by
• the surface is reflected back to the surface.
• the ______________________ is increasing the
• greenhouse gases.

Short wavelengths
long wave radiation
burning of fossil fuels
Common greenhouse gases Water vapor and Carbon
dioxide (CO2) Good at absorbing heat energy.
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C. Factors Affecting Atmospheric Variables

• Temperature measure of the energy of molecules.
• a. ________ -higher _________- lower
  temperatures
• b. ________ - higher _________ - lower
  temperatures
• c. _____________________________
• less fluctuation in temperature of nearby land
  areas.
• (isotherms- connect places of equal temperature)

Latitude
latitudes
Altitude
altitudes
Closeness to large bodies of water -
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2. Moisture liquid(water droplets), solid(ice
snow), gas(water vapor) a.) ____________ -
the higher it is the more moisture the air can
hold. ____________ -the amount of water
vapor the air can hold. ____________
-the air contains all the water vapor it can at
that temperature. ____________ -the
temperature at which condensation occurs.
____________ -the amount of water vapor
actually present in air. _____________ -
a comparison between the amount of moisture in
the air and the amount the air can hold. -
if the air is half full of water the relative
humidity is 50
temperature
capacity
saturated
dewpoint temperature
absolute humidity
relative humidity
Current Data
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___________________ - instrument used to find dew
point - two thermometers (one wet, one dry)
as water evaporates from the wet thermometer
the temperature drops. The drier the air, the
more it evaporates, and the more it drops.
psychrometer
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(No Transcript)
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When is the air saturated?
When is the Relative Humidity 100?
When is the Relative Humidity lowest?
Notice when the high and low temperatures are.
Why?
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3. Pressure the force, or weight, of the air
pushing down on a unit surface area is called
______________________ or ____________________
. a.) _____________ - the greater it is the
higher the pressure. b.) _____________ - the
greater it is the less the density and
pressure of air. ________________ -
instrument used to measure atmospheric
pressure. ________________ - lines on
weather maps joining places with equal air
pressure.
air pressure
atmospheric pressure
density
temperature
barometer
isobars
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Did you notice the pattern?
Highest in the middle.H on map
Lowest in the middle.L on map
Inverse Relationship
Current weather map
c. moisture the more moisture there is in the
air, the _______________ the atmospheric
pressure. d. altitude as altitude increases,
the density and pressure of the air ____________ .
lower
decreases
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D. Air Movement named for the direction they
come from. 1. _______ - large horizontal
movements of air near the Earths surface. 2.
_______ - local horizontal movements of air. 3.
_______ - vertical air movements. pressure
gradient the rate of change in pressure
between two locations. steep pressure
gradient isobars are ________________ and
winds are ___________ . gentle pressure gradient
isobars are ________________ and winds are
_____________ .
winds
breezes
currents
close together
strong
far apart
light
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L
H
H
L
land and sea breezes - occur because land
______________ and ____________ faster than
water. - sea breeze onshore breeze. - land
breeze offshore breeze
heats up
cools off
Air always moves from High to Low air pressure.
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Convection cells -occur because gravity pulls
cool, less dense air toward the Earths surface,
forcing warmer, less dense air to rise.
L
H

• zones of ________________ - high pressure regions
  where air descends and spread out (dry).
• zones of ________________ - low pressure regions
  where air comes together and rises (wet).

divergence
convergence
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Planetary winds - if the earth did not rotate,
air would ______ at the equator and ______ at
the poles, creating one large convection cell. -
since the earth does rotate, winds are modified
by the Coriolis effect. They are deflected to
the ______ in the Northern Hemisphere and
to the ______ in the Southern Hemisphere
(causes wind belts and jet streams).
rise
sink
right
left
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E. Clouds and Precipitation
Condensation process by which gaseous water
vapor changes to ________________ . - must
condense onto a _________________ . - occurs
when air is _________________ . Condensation
nuclei particles in the air such as
______________ that water condenses
on.. Sublimation when water vapor changes
directly into a solid (ice or snow). -
temperature must be below _________ degrees
Celsius. __________ - condensation of water onto
the ground __________ - sublimation of water
onto the ground Clouds collections of tiny
water droplets or ice crystals suspended in the
atmosphere. - as air rises
vertically it expands and cools if it cools to
the dewpoint clouds form..
liquid
surface
saturated
dust or salt
Zero (0)
dew
Cooling expanding
frost
Satellite image
AIR
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Orographic lifting
___________________ - occurs when mountains act
as barriers to the flow of air, _____________ it
to rise to get to the other side. _______________
_ - occurs when warm, lighter air rises over cool
air.
forcing
frontal wedging
Falling, warming air
Rising, cooling air
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Cloud Types 1. _____________ - low rain
clouds 2. _____________ - thunderclouds 3.
_____________ - fair weather (heap clouds) 4.
_____________ - fair weather (high clouds) 5.
_____________ - cloud resting on the Earths
surface Precipitation the falling of liquid or
solid water from clouds 1. _____________ - large
falling drops of water 2. _____________ - fine
falling drops of water 3. _____________ - rain
that freezes as it forms 4. _____________
- falling ice crystals.
Great satellite image
nimbostratus
Cloud images
cumulonimbus
Lightning photos
cumulus
cirrus
fog
rain
drizzle
sleet
snow
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F. Weather Maps Station Models
5. ___________ - when water droplets freeze and
start to fall then they collect more
water and are forced upward they freeze
again, fall, collect more water, and are
forced upward, etc. Seeding placing
___________________ into the atmosphere
where there is some available water vapor.
hailstone
Hail storms
condensation nuclei
Isobars isolines connecting points of equal
__________ Isotherms isolines connecting points
of equal ____________ Pressure gradient high
(steep) where isobars are_____________ this
produces strong winds.
pressure
temperature
close together
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front
_________ -the boundary between two different air
masses. - moving in the direction of the
triangles or half circles
Cold, Dry air-mass
Warm, moist air-mass
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Air Masses

• Air mass huge body of air in the troposphere
  having similar
• __________________________________________________
  ___.
• characteristics depend upon their geographic
  region of origin.
• ______________ -air-masses that develop over
  water (moist).
• _____________ -air-masses that develop over land
  (dry).
• ______________ -air masses that develop in higher
  latitudes (cool).
• ______________ -air-masses that develop in lower
  latitudes (warm).

pressure, moisture, wind and temperature
characteristics throughout.
maritime (m)
continental (c)
polar ( P )
tropical ( T )
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These areas represent the air mass source region.
Jet stream helps control their movement
Current jet stream data.
General direction of motion is WEST to EAST
General direction of motion is WEST to EAST
General direction of motion is WEST to EAST
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_________ (low) low pressure air mass with the
winds moving counter-clockwise toward its
center - often produce rain ______________
(high) high-pressure air-mass with winds
moving in a clockwise direction away from its
center. - cool, clear weather.
cyclone
anticyclone
Current weather map
Another map
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Fronts
Fronts are the boundaries between two
air-masses. - usually _________ - often produce
________________________________
________________________________.
unstable
Clouds, strong winds, precipitation
temperature and pressure changes
- the half circles and triangles point in the
direction the air- masses and front are moving.
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warm fronts

• ___________________ - occur when warm air meets
  and rises over cold air on the ground.
• - long gentle slopes. (1000 km)
• - cause extended periods of
  precipitation.

Current weather map
WARM
COLD
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cold fronts
Current weather map
WARM
COLD
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occluded front
Current weather map
WARM
COLD
COOL
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Mid-latitude Cyclones
stationary front
4. ______________ - occurs when a warm air-mass
and a cold air-mass are side-by-side, with
neither air-mass moving. - gentle
slope, weather similar to that of a warm front.
Current weather map
Fronts-What to look for on maps?

• Begins when cold air pushes down from the north,
  changing a stationary front into a pair of warm
  cold fronts moving around a low pressure center.
• As the low moves eastward, the cold front
  _____________ the slower-moving warm front,
  producing an ___________ .
• A C 12 24 hours
• D 3 4 days

overtakes
occluded front
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A C 12 24 hoursD 3 4 days
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• Cyclones are driven by heat energy released by
  condensation, causing the low pressure to become
  even lower, thereby strengthening the winds.
• In summer, cyclones move about 800km a day, while
  in winter they move about 1,100 km a day. A
  mid-latitude cyclone may cover as much as
  one-half of the entire continental United States
  at one time.
• Warm front would approach and bring
  ___________________
• ____________________ .
• 2. Then you would have ___________________________
  ______
• _____________.
• 3. The cold front would arrive with
  ________________________
• _____________________________________________ .

a long period of
light precipitation.(generally)
a period of clearing and warm humid
weather
brief heavy showers,
followed by clearing and cooling
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• City 2
• Temperature- warm,steady
• Pressure- steady
• Precipitation- none, but humid

What is the weather like if you are in city

• City 1
• Temperature- decrease
• Pressure- increase
• Precipitation- brief,heavy, thunderstorms possible

2
1
3

• City 3
• Temperature- increase
• Pressure- decrease
• Precipitation- light, steady, long lasting rain

1
2
3
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G. Severe Weather
Hurricane

• _______________ a doughnut shaped ring of strong
  counter-clockwise winds exceeding 115 km/hr (
  75 mph) surrounding an area of extremely low
  pressure at the center.
• cant stand and have a hard time breathing.
• wind speed increases as you move toward the
  center of the storm.

Hurricane graphics
Hurricane Hazards
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eye

• _____ - relatively calm area of clear skies in
  the middle of the storm.
• ___________ - dome of water 65 to 80 km wide
  near the point where the eye reaches the
  land.
• most common in late summer and early fall.

storm surge
Hurricane Hazards
Hurricane Names
Hurricane Tracks
Hurricane Strike Frequency
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2. ______________ ( twister, cyclones ) -
violent funnel shaped windstorms that extend
downward from a cumulonimbus cloud. -
winds can exceed ( ____ km/hr) (
mph) - most common from spring to early
summer. - pressure differences between the
inside and outside is around 25 mb but drops
of up to 200 mb have been observed. -
usually less than a mile in diameter - short
lifetime (
) - generally form in the vicinity of
intense _________ fronts and squall lines
associated with mid-latitude cyclones.
Tornadoes
Tornado images
Fujita Scale
500
300
A few minutes
cold
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• Squall lines -
  
• form when
  from the north meets
• 
  from the Gulf of Mexico.
• the greater the difference in the air-masses, the
  stronger the storm.
• Most often occur in
  
• Between tornadoes are reported
  in the United States each year.
• ___________________
• - tornadoes over water.

moving lines of thunderstorms
continental polar air
maritime tropical air
the central United States in spring
700 800
Waterspouts
Tornado Information
Tornado Damage
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The warm lake modifies the airmass and modified
air rises and cools allowing moisture to condense
into snow clouds. The modified air slows down and
"piles up" as it approaches the downwind shore. 
The lift is further enhanced by Orographic
features (hills, mountains) downwind of the body
of water.  The result is lake effect snow.
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Snow Day Central
You can clearly see the snowbelts to the lee of
Lakes Erie and Ontario on the map.  To the east
of  Lake Erie, annual snowfall exceeds 150
inches.  The higher elevations known as the Tug
Hill Plateau, receives of more than 200 inches a
year.
In fact, the town of Hooker in Lewis county,
recorded 466 inches of snow during the winter of
1976-77!  Orographic features tend to enhance
snowfall rates by providing additional lift as
the air crosses the region.
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Faster
Remember Land heats and cools.
Than water!!!!!!
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Wind Direction determines location!