ATMOSPHERE AND WEATHER
FACTORS
BOOK I CH 1 SEC 4 AND CH 2 SEC 1,2,4
LAYERS OF THE ATMOSPHERE
• THE FOUR MAIN LAYERS OF THE ATMOSPHERE ARE CLASSIFIED ACCORDING TO
CHANGES IN TEMPERATURE.
• THESE LAYERS ARE:
• TROPOSPHERE
• STRATOSPHERE
• MESOSPHERE
• THERMOSPHERE
1ST LAYER
• TROPOSPHERE – LOWER LAYER OF EARTH’S ATMOSPHERE, WHERE WEATHER
OCCURS
• TROPO – MEANS “TURNING” OR “CHANGING”
• THE DEPTH OF THE TROPOSPHERE VARIES FROM MORE THAN 16 KILOMETERS
ABOVE THE EQUATOR TO 9 KILOMETER ABOVE THE POLES
• CONTAINS ALL MOST OF THE MASS OF THE ATMOSPHERE
• AS YOU GO HIGHER THE TEMPERATURE DECREASES
• FOR EVERY 1 KILOMETER OF ALTITUDE THE TEMP DECREASES BY 6.5°C
2ND LAYER
• STRATOSPHERE – SECOND-LOWEST LAYER OF EARTH’S ATMOSPHERE, THE
OZONE LAYER IS LOCATED IN THE UPPER STRATOSPHERE
• STRATO (STRATUM) MEANS “LAYER” OR “SPREADING OUT”
• LOWER STRATOSPHERE IS -60°C
• OZONE LAYER IS THE UPPER LIMIT
• WHICH ABSORBS ENERGY FROM THE SUN, THE ENERGY IS CONVERTED INTO
HEAT WARMING THE AIR
3RD LAYER
• MESOSPHERE – MIDDLE LAYER OF EARTH’S ATMOSPHERE, THE LAYER IN WHICH
MOST METEOROIDS BURN UP
• MESO – MEANS “MIDDLE”
• BEGINS 50 KILOMETERS ABOVE EARTH’S SURFACE AND ENDS AT 80 KILOMETERS
• OUTER MOST IS THE COLDEST AT NEAR -90°C
4TH LAYER
• THERMOSPHERE – OUTERMOST LAYER OF EARTH’S ATMOSPHERE
• AIR IS VERY THIN (0.001% AS THICK AS AT SEA LEVEL)
• GOES FROM 80 KILOMETERS TO OUTER SPACE
• THERMO – MEANS “HEAT”
• VERY HOT (1,800°C), HOT ENOUGH TO MAKE STEEL
• DIVIDED INTO 2 LAYERS
• IONOSPHERE – LOWER PART OF THE THERMOSPHERE, WHERE ELECTRICALLY
CHARGED PARTICLES CALLED IONS ARE FOUND
• BEGINS AT 80 KILOMETERS TO 550 KILOMETERS
• AURORA BOREALIS – A COLORFUL, GLOWING DISPLAY IN THE SKY CAUSED WHEN
PARTICLES FROM THE SUN STRIKE OXYGEN AND NITROGEN ATOMS (NORTHERN
LIGHTS)
• EXOSPHERE – OUTER LAYER OF THE THERMOSPHERE, EXTENDING OUTWARD
INTO SPACE
• STARTS AT 550 KILOMETERS FOR THOUSANDS OF KILOMETERS
• Section 4 Review page 36
• Questions 1-4
WEATHER FACTORS
CH 2 SEC 1,2 AND 4
ENERGY FROM THE SUN
• ELECTROMAGNETIC WAVES – A FORM OF ENERGY THAT CAN TRAVEL THROUGH
SPACE
• RADIATION – DIRECT TRANSFER OF ENERGY BY ELECTROMAGNETIC WAVES
• MOST OF THE ENERGY FROM THE SUN REACHES EARTH IN THE FORM OF VISIBLE
LIGHT AND INFRARED RADIATION, AND A SMALL AMOUNT OF ULTRAVIOLET
RADIATION
• INFRARED RADIATION – FORM OF ENERGY WITH WAVELENGTHS THAT ARE
LONGER THAN VISIBLE LIGHT
• ULTRAVIOLET RADIATION – FORM OF ENERGY WITH WAVELENGTHS THAT ARE
SHORTER THAN VISIBLE LIGHT
ENERGY IN THE ATMOSPHERE
• SOME OF THE ENERGY IS ABSORBED WITHIN THE ATMOSPHERE
• WATER VAPOR AND CARBON DIOXIDE ABSORB INFRARED RADIATION
• OZONE LAYER ABSORBS THE ULTRAVIOLET RADIATION
• CLOUDS REFLECT SOLAR ENERGY BACK INTO SPACE
• SCATTERING – REFLECTION OF LIGHT IN ALL DIRECTIONS
• THIS SCATTERING CAUSE THE DAY TIME SKY TO LOOK BLUE
ENERGY AT EARTH’S SURFACE
• WHEN THE EARTH’S SURFACE IS HEATED, IT RADIATES SOME OF THE ENERGY
BACK INTO THE ATMOSPHERE AS INFRARED RADIATION
• IT CANNOT TRAVEL ALL THE WAY THROUGH THE ATMOSPHERE BACK INTO
SPACE
• GREENHOUSE EFFECT – PROCESS BY WHICH HEAT IS TRAPPED IN THE
ATMOSPHERE BY WATER VAPOR, CARBON DIOXIDE, METHANE, AND OTHER
GASES THAT FORM A “BLANKET” AROUND THE EARTH
• THIS IS A NATURAL PROCESS THAT KEEPS EARTH’S ATMOSPHERE AT A
TEMPERATURE THAT IS COMFORTABLE FOR MOST LIVING THINGS
• HUMAN ACTIVITIES HAVE INCREASED THE CARBON DIOXIDE, WHICH COULD BE
WARMING THE EARTH
HEAT TRANSFER
• THERMAL ENERGY – THE ENERGY OF MOTION IN THE
MOLECULES OF A SUBSTANCE
• TEMPERATURE – THE AVERAGE AMOUNT OF ENERGY OF
MOTION IN THE MOLECULES OF A SUBSTANCE
• AIR TEMPERATURE IS MEASURED USING A
THERMOMETER
• THERMOMETER – INSTRUMENT USED TO MEASURE
TEMPERATURE
HOW HEAT IS TRANSFERRED
• HEAT – ENERGY TRANSFERRED FROM A HOTTER OBJECT TO A COOLER ONE
• HEAT IS TRANSFERRED IN THREE WAYS:
• RADIATION
• CONDUCTION
• CONVECTION
RADIATION
• THE HEAT THAT YOU FEEL FROM THE SUN OR A CAMPFIRE TRAVELS DIRECTLY
TO YOU AS RADIATION
• YOU CANNOT SEE IT BUT YOU FEEL IT AS HEAT
CONDUCTION
• CONDUCTION – DIRECT TRANSFER OF HEAT FROM ONE SUBSTANCE TO
ANOTHER SUBSTANCE THAT IT IS TOUCHING
• WORKS WELL IN SOME SOLIDS, SUCH AS METALS, BUT NOT AS WELL IN LIQUIDS
AND GASES
• AIR AND WATER DO NOT CONDUCT HEAT VERY WELL
Why is this an example of
conduction?
CONVECTION
• CONVECTION – TRANSFER OF HEAT BY THE
MOVEMENT OF A FLUID
• IN FLUIDS (LIQUIDS AND GASES), MOLECULES CAN
MOVE FROM PLACE TO PLACE
• AS THEY MOVE THEY TAKE THEIR HEAT ALONG
WITH THEM
This is how
heat transfer in
the
Troposphere
THE
HYDROLOGICAL
CYCLE
(THE WATER CYCLE)
The hydrological cycle is the system which
describes the distribution and movement of water
between the earth and its atmosphere. The model
involves the continual circulation of water between
the oceans, the atmosphere, vegetation and land.
The water cycle is driven
by energy from the sun.
The water cycle has
four stages: storage,
evaporation,
precipitation, and
run-off.
Describing the Cycle:
Solar energy powers the cycle. Heat energy
from the sun causes evaporation from water
surfaces (rivers, lakes and oceans) and….
Evaporation –
process by which
water molecules
in liquid water
escape into the
air as water
vapor
…transpiration is essentially
evaporation of water from
plant leaves.
(In other words, it’s
like plants sweating.)
Condensation –
process by which
molecules of water
vapor in the air
become liquid
water
When a large amount of water vapor condenses, it
results in the formation of clouds.
HOW CLOUDS ARE FORMED
• CLOUDS OF ALL KINDS FORM WHEN WATER VAPOR IN THE AIR BECOMES LIQUID
WATER OR ICE CRYSTALS
• DEW POINT – TEMPERATURE AT WHICH CONDENSATION BEGINS
• WHEN YOU LOOK AT A CLOUD, YOU ARE SEEING MILLIONS OF TINY ICE
CRYSTALS OR WATER DROPLETS
• FOR WATER VAPOR TO CONDENSE, TINY PARTICLES MUST BE PRESENT LIKE SALT
CRYSTALS, DUST FROM SOIL, AND SMOKE
• WATER THAT CONDENSES FROM THE AIR ONTO A COLD SURFACE IS CALLED
DEW
• FROST IS ICE THAT HAS BEEN DEPOSITED DIRECTLY FROM THE AIR ONTO A
COLD SURFACE
TYPES OF CLOUDS
• METEOROLOGISTS CLASSIFY CLOUDS INTO THREE MAIN TYPES:
• CUMULUS – CLOUDS THAT FORM LESS THAN 2 KILOMETERS ABOVE THE
GROUND AND LOOK LIKE FLUFFY, ROUNDED PILES OF COTTON
• STRATUS – CLOUDS THAT FORM IN FLAT LAYERS
• CIRRUS – WISPY, FEATHERY CLOUDS MADE MOSTLY OF ICE CRYSTALS THAT
FORM AT HIGH LEVELS, ABOVE ABOUT 6 KILOMETERS
Wind energy; ‘advection’ may move clouds over land
surfaces where …
…precipitation occurs, when the water in the clouds gets
too heavy, the water falls back to the earth -- either as
rain or snow depending on altitude.
The rainwater flows, either over
the ground (run off) into rivers and
back to the ocean, or…
… infiltrates downwards through
the soil rocks where it is returned
to
the
oceans
through
groundwater flow.
The Water Cycle Balanced
Usually the water cycle is in balance, and the amount of
precipitation falling will slowly soak into the ground and
eventually reach the rivers. However, if rain falls for a
long period of time or if the ground is already soaked or
saturated with water then the chance of flooding is
increased.
Water Cycle: A closed system
 The hydrological cycle is a good example of a closed
system: the total amount of water is the same, with
virtually no water added to or lost from the cycle.
 Water just moves from one storage type to another.
 Water evaporating from the oceans is balanced by
water being returned through precipitation and surface
run off.