Download S NOTES Weather

Name_____________________________
CHAPTER 7 WEATHER NOTES
Date______________
Energy
1) The Universe is made up of ___________________________ and energy
2) Electromagnetic energy travels at the speed of light, which is ___________
meters/s or 1.9 x 10^5 miles/s
3) The nearest star after the sun, os Proxima Centauri, which is 4.3 light years away.
Energy Changes with States of Water – ESRT pg 1
1) Latent Heat- __________________ that is absorbed or released during a change
in temperature.
a) When water goes from a Solid  Liquid and Liquid  Gas energy
_______________________ because molecules can move more freely
b) When water goes from Gas  Liquid and Liquid  Solid energy is
released because molecules are moving __________
________________.
2) Heat of Fusion = energy needed to _____________ one gram of a substance at
its melting point = 80 cal/g (little energy used) or _____________ J/g
3) Heat of Vaporization = energy needed to change one gram of a substance from
liquid water to vapor = 540 cal/g (more energy used) or ___________J/g
a) 1 calorie = 4.18 Joule, both units of energy. A Joule is energy that is
expanded by applying a force
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Specific Heat – ESRT pg 1
1) Specific Heat- amount of heat needed to raise the temperature of 1 gram of
substance 1C
a) Water as a liquid must absorb more energy than any other material,
for a temperature change and it heats up and cools more slowly
compared to other materials.
Atmospheric Variables- things that can be measured and change from moment to
moment.
1) Temperature- Measures the average ______________________ energy of
_____________________________.
a) Heat enters the atmosphere from the sun as solar radiation.
2) Average Kinetic Energy- kinetic energy is the energy of __________________.
A
B
C
A) The slower the molecules vibrate, the colder the material. B) If they vibrate fast, it is hot. C) Mix hot and cold and you get
warm. The hot molecules still move fast and the cold move slowly, but the temperature average out to warm.
a) The temperature of any material is an average of all of the kinetic
energies- hence Average Kinetic Energy.
3 ways to Measure temperature:
Fahrenheit
Water freezes at ______°
Water boils at 212 °
Celsius AKA Centigrade (100 levels)
Water freezes at 0 °
Water boils at _______ °
Makes more sense and is easier to make a thermometer
Kelvin Same scale as Celsius but 0 means zero energy
No degrees mark for Kelvin
0K means that all atomic vibrations stop.
Converting Temperature
To convert °C into °F: °F = °C x1.8 + 32
To convert °F into °C: °C = (°F - 32) ÷ 1.8
To convert °C into Kelvin K = °C + 273.15
To convert K into °C: °C = K -273.15
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Facts about Temperature and Energy
1) Energy always goes from ____________________________________. Heat
flows from hot to cold (source to sink).
2) There is no such thing as “cold”. Cold is just an __________________ of heat.
3) Ice doesn’t add cold to something; it sucks the heat into it.
Heat Transfers
1) Radiation -the transfer of heat in the form of _____________________.
a) The Sun’s rays are _____________________, visible waves. When they
hit the earth they reradiate back as long, infrared waves
b) The Greenhouse Effect- IR (infrared) light that is re-radiated from the
ground is stopped from reaching space by extra “greenhouse gasses” in the
air. These extra gases can come from, CO2 from burning fossil fuels, the
clearing of trees and Fart gas from cows (methane).
2) Conduction- Heat __________________________ from one object to another
through touch.
3) Convection- Hot Rises, Cold Sinks
a) Caused by __________________________ differences: Hot air
expands and gets less dense. Cold air contracts and gets denser.
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Structure of the Atmosphere
1) Meteorology- is the study of the ______________________- including weather.
2) Weather- is the ________________________ of the atmosphere, which includes
temperature, wind, clouds and precipitation. It can change from time to time and
place to place.
3) Climate- is the __________
over a long period of time.
______
___________________ an area has
Layers of the atmosphere: separated by the variation of ___________________________
patterns.
In these two models, you can see how most of the atmosphere is concentrated near the surface due to the pull of gravity.
1) Troposphere- we live in the troposphere, it’s from 0 or sea level to ______ km.
a) Gets ________________________ as you go up.
b) All _________________________________ occurs here
c) All _________________
_______________ in the atmosphere is here
2) Stratosphere - Temperatures get __________
as you go up.
a) Home of the ___________________.
3) Mesosphere & Thermosphere- Upper layers
of the atmosphere.
a) The air is very ______________ here.
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Air Pressure - The _______________________ of the air above you. The further away
from the Earth’s surface we get, the less pressure. (ESRT pg 13)
1) We use a barometer to measure pressure. One atmosphere of pressure or
1013.2mb = 29.92 inches (ESRT pg13)
2) Water molecules weigh less than air molecules, so when air is humid, it is
actually lighter.
a) Sinking air pushes down more- ___________________ air is usually high
pressure on the barometer.
b) Rising air pushes down less- ________________ air is usually low
pressure on the barometer.
The Coriolis Effect - deflects things to their right in the Northern Hemisphere. Caused by
the rotation of the Earth counterclockwise.
Thumbs Up/Thumbs Down Rule
-Your thumb represents the High or Low pressure
with your right hand
-Your fingers wrap around your palm the way that
the wind spirals around the pressure system.
-LOW Pressure sucks in and moves
counterclockwise, so we put our thumb up!
-HIGH Pressure goes out clockwise, so we put our
thumbs down!
1) ______ Pressure flows outward and clockwise (cw) (in the N. Hemisphere)
a) Usually calm weather and clear skies
2) ______ Pressure flows inward and counterclockwise (ccw)(in the N. Hemi.)
a) Usually rain, because air rises and condenses and can cause high winds
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Air Pressure Conversion
1) When converting from millibars to station model code, use only the last three
digits and throw out the decimal point.
2) When converting from station model code to millibars, is the code is 500 or
higher, put a 9 in front of it and if it is below 500, put a 10 in front of it.
Example: 1028.0mb  280 in station model code
138 in station model  1013.8mb
Wind- when air travels from ______________ pressure to ___________. (ESRT pg 14)
1) The ________________________ between isobars determines the wind speed.
Example: Big Difference in Pressure =(Steep Gradient) = fast wind
Small Difference in Pressure =(Gentle Gradient) = gentle winds
Sea Breeze-Land Breeze-Water is stubborn. It does not want to change its temperature.
It has a high specific heat.
1) During the day, the land _________________ _________ more than the water
and will create convection currents.
2) At night, land will __________________ ______________ ______________
than the water and create convection currents in the opposite direction.
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Orographic Effect (Mountian Barrier) When air is forced to rise because it hits
mountains, it will cool and condense. In the US, the strong prevailing winds generally move
from West to East, much like weather systems.
1) On the Windward side of the mountains it will have a _______________ climate.
2) On the Leeward side, there will be a ______________ climate that is usually
warmer than the windward
(Lenticular cloud- Caused by release of heat during
condensation on windward and usually happens on a big
island like Hawaii)
Wind Direction -Winds are named for the direction that they come from. On a map
direction is shown with a line showing where it came from.
Wind Speed
Write the wind direction and wind speed for each
station model
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Water Content & Humidity
1) The amount of water in the air is called ____________________________.
3) The ability of air to “hold” water changes depending on the _______________.
a) Air transports water, rather than holds it.
3) Relative humidity is expressed as a % and it tells "how full" the air is with water.
a) 100% is full and can't hold any more. It is _______________________.
b) When there’s no R.H, the air feels cooler and vice versa.
4) Water gets into the air by _______________________ (change from a liquid to
gas) or sublimation (changing from a solid like snow or ice to a gas). Sublime means
to skip a step
a) To get the water out of the air it either condenses (changes from a gas to
liquid) or sublimes.
Measuring Relative Humidity (pg 12)
1) The “Dry Bulb,” don’t let it fool you, it is just a thermometer. It measures the air
temperature. Duh!
2) The “Wet Bulb” has a little wet booty tied to the bottom, which gets cool when
water evaporates.
3) On A Dry Day...A lot of moisture will evaporate. The wet bulb will be a lot
cooler than the dry bulb.
4) On A Humid Day...A little bit of moisture will evaporate. The wet bulb will not be
much cooler than the dry bulb.
Dewpoint – the point at which air must be ___________________ to become saturated
with water. If the temperature falls below the dew point, dew forms.
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Weather
1) A ___________________________________or a small piece of dust, smoke, or
salt acts as a surface for condensation to occur.
2) ____________________ is when water condenses in the atmosphere and falls
to the surface. Precipitation cleans out the atmosphere by pulling down the
condensation nuclei (pollution)
a) When warm air rises, it cools and can’t transport as much moisture so it
falls as precipitation.
Storms
1) Cyclone- any inward and counterclockwise air circulation around a _____pressure center.
a) Tornado- AKA Twister; a small, compact storm with _______________
winds. Can be predicted a few minutes early with Doppler radar.
b) Extremely localized ___________ - ____________________ center.
99.9% in Northern Hemisphere spin ccw.
The Fujita Scale based on the width and wind speed of the funnel.
F-Scale
Number
Intensity Phrase
Wind
Speed
Type of Damage Done
F0
Gale tornado
40-72
mph
Some damage to chimneys; breaks branches off trees; pushes over shallowrooted trees; damages signboards.
F1
Moderate tornado
73-112
mph
The lower limit is the beginning of hurricane wind speed; peels surface off
roofs; mobile homes pushed off foundations or overturned; moving autos
pushed off the roads; attached garages may be destroyed.
F2
Significant
tornado
113-157
mph
Considerable damage. Roofs torn off frame houses; mobile homes
demolished; boxcars pushed over; large trees snapped or uprooted; light
object missiles generated.
F3
Severe tornado
158-206
mph
Roof and some walls torn off well constructed houses; trains overturned;
most trees in forest uprooted
F4
Devastating
tornado
207-260
mph
Well-constructed houses leveled; structures with weak foundations blown off
some distance; cars thrown and large missiles generated.
F5
Incredible tornado
261-318
mph
Strong frame houses lifted off foundations and carried considerable distances
to disintegrate; automobile sized missiles fly through the air in excess of 100
meters; trees debarked; steel reinforced concrete structures badly damaged.
319-379
mph
These winds are very unlikely. The small area of damage they might produce
would probably not be recognizable along with the mess produced by F4 and
F5 wind that would surround the F6 winds. Missiles, such as cars and
refrigerators would do serious secondary damage that could not be directly
identified as F6 damage. If this level is ever achieved, evidence for it might
only be found in some manner of ground swirl pattern, for it may never be
identifiable through engineering studies
F6
Inconceivable
tornado
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2) _______________________- AKA Typhoon (in Pacific) a large, organized storm
with strong winds and heavy rain. Biggest danger is the storm surge in coastal areas.
a) Massive ______________________ that can be more than 300 miles in
diameter and feeds on warm water.
3) Mid Latitude Low- a ____________ pressure system in the middle latitudes.
a) AKA Nor’ Easter (North Easter) or Alberta Clipper can happen any time
of year, but are well known during the winter months
Development of The Mid Latitude Low
This weather system starts when cool and warm air masses meet.
Low develops over the air masses.
The Low continues to spin, creating a warm front and a cold front.
As the air masses mix, the fronts overlap in the center creating an occluded front. In the end, the air mixes and the system breaks down.
Rain will fall in front of the warm front and right on top of the cold front.
A well-developed Mid-Latitude Low
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4) Prevailing Winds- Push _________________________ around
a) Most of the time our winds come from the __________________,
therefore our weather will usually come from the west.
b) Prevailing Westerlies- the typical west wind in most of the United States.
Doldrums and Horse
latitudes- area of little
precipitation and calm winds
Air Masses
1) The source of an air mass determines its characteristics.
a) Maritime- _______________ (over water)
b) Continental- __________________ (over LAND)
c) _________________________- hot (warm latitudes)
d) ________________- _______________________________________
Identify the air masses
1) cT= Continental
Tropical= dry and hot
2) cP
3) mT
4) mP
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Fronts -the leading edge of an ___________________.
1) If it is the front of a cooler air mass, it will be
a ________________.
2) If it is the front of a warmer air mass, it will
be a ___________________.
How to tell where a front belongs on a map
1) A front will be located where the
___________________ changes rapidly in a
short distance.
a) Isotherms will be close together.
Types of Fronts
1) The Cold Front- where cold, __________, __________________ air displaces
warm, moist, unstable air. As always, the warmer air rises
a) Moves _____________________ than the warm front.
b) Short period (1-2hrs) of heavy rain & maybe thunder occur on top of the front.
c) You'll see cumulus clouds when the cold front is approaching
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2) The Warm Front- _____________ moving humid air masses replace cold dry air
a) Gentle rain for a long period (1-2 days) of time fall in front of the front.
b) You'll see cirrus clouds become thicker, when a warm front approaches.
3) The Occluded Front- _______________ moving cold front takes over a _____
moving warm front
a) A long period of gentle rain followed by heavy rain & possibly a t-storm
b) People usually don't notice a temperature change.
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4) Stationary front- where 2 air masses come together and neither is strong enough to
replace the other.
a) Can be cloudy for hours or days and long precipitations
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