Ch. 11-13 I. Atmosphere - layer of gas that surrounds the Earth.

A. Composition

1. 78% - N2 2. 21% - O2 3. 0%-4% - water vapor 4. 1% - other gases

5. Ozone - O3 - protects us from UV radiation. B. Smog - smoke and mixing with sulfur dioxide and nitrogen dioxide 1. From the burning of coal, gasoline, and other fossil fuels

C. solids (dust and ice) and liquids (water). II. Layers - divided according to major changes in temperature

A. Troposphere - the lowest layer we live here weather occurs here

1. 75% of all atmosphere gases 2. ↓ temp. with ↑ altitude 3. Tropopause - boundary between troposphere and the next layer

B. Stratosphere - 2nd layer

1. Jet stream - strong west .

2. Ozone (O3) - is found here. 3. ↑ temp. with ↑ altitude. 4. Stratopause - boundary between stratosphere and mesosphere.

C. Mesosphere - area where meteors burn up

↓ temp. with ↑ altitude

Mesopause - boundary between mesosphere and thermosphere

D. Thermosphere - means "heat sphere" 1. Very thin air (1/10,000,000) of the earth's surface

2. High temperature - N2 and O2 absorb U.V. light and turn it into heat 3. Cannot measure with thermometer

D1. Ionosphere - lower part of thermosphere 1. Layer of ions 2. Used for radio waves 3. When particles from the sun strike the ionosphere it causes: Auroras - northern and southern lights

D2. Exosphere - layer that extends into outer space 1. Satellites orbit here

III. Air pressure - the pressure that air molecules force upon an object. A. Decreases with altitude. B. Barometer - instrument that measures . (Altimeter?) C. Warm air is less dense than cold air. D. HIGH pressure is usually clear and sunny.

E. LOW pressure indicates cloudy weather. IV. Ozone– absorbs U.V. radiation, found in the stratosphere. A. U.V. can cause sunburn, skin cancer and other health problems.

B. Chlorofluorocarbons (CFC) – molecules that destroy the ozone by breaking up

O3 into O2 & O. (chlorine is the destroying element) V. Energy transfer

A. Three things that happen to light when it reaches earth

1. Reflected back into space – 30% a. and atmosphere - 25% b. Surface of earth - 5%

2. Absorbed by clouds and atmosphere - 20%

3. Absorbed by the earth's surface - 50% B. Radiation - can travel through a vacuum 1. Can pass through the atmosphere but cannot travel back out

C. Conduction - direct contact molecules bump into each other D. - transfer of energy by a fluid 1. Due to density differences a. Warm air rises b. Cold air sinks VI. Movement of air A. Coriolis effect - because the earth rotates it causes air in the to curve to the right, and in the to the left. B. Wind systems 1. Doldrums - windless zone at the due to rising air 2. Trade (east wind) - 15° to 30° a. Air flows to the equator

Trade winds 2. (east wind) - 15° to 30° latitude 1. Air flows to the equator

Trade winds

Trade winds 3. Prevailing - 30° to 60° latitude

Prevailing Westerlies

Trade winds 3. Prevailing Westerlies - 30° to 60° latitude

Prevailing Westerlies

Trade winds

Trade winds

Prevailing Westerlies 4. Polar easterlies - 60° to 90° latitude

Polar Easterlies

Prevailing Westerlies

Trade winds

Trade winds

Prevailing Westerlies 4. Polar easterlies - 60° to 90° latitude

Polar Easterlies

Prevailing Westerlies

Trade winds

Trade winds

Prevailing Westerlies

Polar Easterlies 5. Horse - (Windless) 30°N and 30°S latitude

Polar Easterlies

Prevailing Westerlies

Trade winds

Trade winds

Prevailing Westerlies

Polar Easterlies Two belts of latitude where winds are light and the weather is hot and dry. They are located mostly over the oceans, at about 30° lat. in each hemisphere, and have a north-south range of about 5° as they follow the seasonal migration of the sun. The horse latitudes are associated with the subtropical and the large-scale descent of air from high-altitude currents moving toward the poles. After reaching the earth’s surface, this air spreads toward the equator as part of the prevailing trade winds or toward the poles as part of the westerlies. The belt in the Northern Hemisphere is sometimes called the “calms of Cancer” and that in the Southern Hemisphere the “calms of Capricorn.” The term horse latitudes supposedly originates from the days when Spanish vessels transported horses to the West Indies. Ships would often become becalmed in mid-ocean in this latitude, thus severely prolonging the voyage; the resulting water shortages would make it necessary for crews to throw their horses overboard. Already wrote this down. No need to do again. 6. Jet stream - narrow high speed band of wind. NOAA Aerosols Satellite Imagery. Tanya Fransen (NOAA) 11-19-2017 I shared this last week on my Facebook page, and thought you all may appreciate it as well. I watched it about 5 times straight, and each time saw something I hadn't noticed before. It's a stunning animation from NASA that shows the aerosols in the atmosphere, from wildfire smoke, to salt particles concentrations over the oceans to the dust coming off the . It's pretty stunning if you have any bit of weather geek in you at all. :) • It starts in August and goes through the end of October. Maybe show it to your students and ask what things they see beyond what the video discusses (Ophelia!!)? A few that may not stand out at first: • 1. Tropical systems actually going east to west and making it across Mexico from the Carribean to the Pacific. (8-15 seconds in) • 2. The diurnal cycles of wildfires, it really shows up in the Southeast in the Oct time frames in little puffs. • 3. The direction the NW smoke goes based on the weather systems coming through. • https://www.youtube.com/watch?v=h1eRp0EGOmE NO notes over the “Breezes” Breezes No Notes A. Sea breeze - occurs during the day 1. land heats faster then the ocean, the air over the land rises and cool ocean air rushes to replace it. No Notes B. Land breeze - occurs at night 1. air over land cools faster then over the ocean. No Notes C. Valley breeze- Day No Notes D. Mountain breeze- Night No Notes

E. Summer - F. Winter Monsoon - dry 12-1 Weather - The current state of the atmosphere and current conditions

I. Factors that determine weather. A. Temperature B. Pressure C. Water vapor II. - amount of water vapor in the air

A. Warm air holds more water vapor than cool air.

B. Relative humidity - amount of water vapor in the air compared to the amount it can hold at a particular temperature. 1. Psychrometer - Instrument used to measure R.H. C.Dew point - temperature at which the air is saturated and condensation takes place. III. Clouds – made of water droplets. A. Types of clouds 1. Cirrus - high altitude, usually ice crystals, fair weather, may indicate approaching . (Mare’s Tails) 2. Stratus - "layered ", may produce . a. Fog - stratus cloud on the ground.

3. Cumulus - dense, billowy clouds, usually indicate fair weather. a. Cumulonimbus – ("thunder heads“), severe weather, anvil on top.

Cirrocumulus Stratocumulus

Nimbostratus Cirrostatus “rain” B. Precipitation - moisture that falls from the sky.

1. Rain - temperature is above freezing when formed.

2. Snow - temperature is below freezing when formed.

3. Sleet - snow forms, then melts, then freezes. 4. Hail - when drops of water freeze in layers. -- Formed in where rising air causes the hail to rise and fall within the cloud. A new record for the largest hailstone ever was set in 2010! It fell on July 23, in Vivian, South Dakota. It was 8 inches in diameter, 18.62 inches in circumference, and weighed 1.93 pounds

RAINBOW

If you had no idea at all about what a rainbow is or what causes it, you might actually believe some of the legends that different ancient cultures have created to explain it. Rainbows are among the most beautiful of nature’s displays. A rainbow isn’t really a “thing” and it doesn’t exist in a particular “place.” It is an optical phenomenon that appears when sunlight and atmospheric conditions are just right—and the viewer’s position is just right to see it. When can you see a rainbow? A rainbow requires water droplets to be floating in the air. That’s why we see them right after it . The Sun must be behind you and the clouds cleared away from the Sun for the rainbow to appear. Why is a rainbow a bow—or arc? A full rainbow is actually a complete circle, but from the ground we see only part of it. From an airplane, in the right conditions, one can see an entire circular rainbow. What happens in the water droplets? The sunlight shines on a water droplet. As the light passes into the droplet, the light bends, or refracts, a little, because light travels slower in water than in air (because water is denser). Then the light bounces off the back of the water droplet and goes back the way it came, bending again as it speeds up when it exits the water droplet.

Light enters a water droplet, bending as it slows down a bit going from air to denser water. The light reflects off the inside of the droplet, separating into its component wavelengths—or colors. When it exits the droplet, it makes a rainbow. Why the colors? Sunlight is made up of many wavelengths—or colors—of light. Some of those wavelengths get bent more than others when the light enters the water droplet. Violet (the shortest wavelength of visible light) bends the most, red (the longest wavelength of visible light) bends the least. So when the light exits the water droplet, it is separated into all its wavelengths. The light reflecting back to you, the observer with the Sunlight coming from behind you, from the water droplets will appear separated into all the colors of the rainbow! Violet will be on the bottom and red on the top. A secondary rainbow appears if the sunlight is reflected twice inside the water droplets. Secondary rainbows are fainter, and the order of the color is reversed, with red on the bottom. Sometimes you can see another, fainter secondary rainbow above the primary rainbow. The primary rainbow is caused from one reflection inside the water droplet. The secondary rainbow is caused by a second reflection inside the droplet, and this “re-reflected” light exits the drop at a different angle (50° instead of 42° for the red primary bow). This is why the secondary rainbow appears above the primary rainbow. The secondary rainbow will have the order of the colors reversed, too, with red on the bottom and violet on the top. Rainbow legends The Karens, a group of people in Burma, once considered rainbows to be dangerous demonic spirits that devoured the souls of humans and caused sudden or violent deaths. They thought that such activity made the rainbow thirsty enough to appear in the sky and dip down to Earth to drink water. There was a belief among ancient Polynesians that a rainbow was a ladder that their heroes climbed to reach heaven. The folklore of ancient Greece taught that Iris, wife of the god Zephyrus, caused rainbows. Iris was a messenger between mortals and the gods. She ran back and forth, dressed in shimmering multicolored robes. The word "iridescence" comes from Iris's robes. An old proverb says that a house that is overarched by a rainbow will soon experience a disaster or if you walk through the end of the rainbow, your family will experience a disaster within a year. IV. Changes in weather A. - large body of air that has the same properties as the surface over which it developed. 1. Continental polar - dry and cold

2. Continental tropical - dry and warm

3. Maritime polar – wet and cold

4. Maritime tropical - wet and warm Video B. Front - a boundary where two air masses meet. 1. Warm front - mass of warm air that overtakes a cold air mass. a. Rain and showers.

Diagram Map Current Map 2. Cold front - mass of cold air meets and replaces a mass of warm air. a. violent , fair and cool weather when it passes.

Diagram Map Current Map 3. Stationary front - warm and cold air masses meet; but no movement occurs. a. Lasts for several days, precipitation does occur.

Diagram Map Current Map 4. Occluded front - when two cold air masses merge and force the warm air to rise.

Diagram Map Current Map C. Air pressure systems 1. High pressure ( H ) - air is sinking a. Fair weather b. Low relative humidity

c. Rotates clockwise in N.H. (Northern Hemisphere) d. Also called “” 2. Low Pressure ( L ) - air is rising a. clouds, possible precip. b. Unstable air c. Rotates counter clockwise (N.H.) d. Also called “” Ch. 13 I. Thunderstorms (cumulonimbus) - rapid upward movement of warm moist air. Video A. Lightning - occurs when current flows from regions of opposite electrical charges. (50,000O F) B. Thunder - rapid heating of air around the lightning bolt. What to do? Types of Lightning Calculation Distance This is a very strong reminder of what Lightning can do. This was somewhere in McCook County, SD last night 5-25-16. There is 21 head of cattle that were around this metal bale feeder when it was hit with one bolt of lightening and it killed them all. That is about $45,000 worth of loss. As the severe weather starts to roll in this summer please keep this in mind. If you start to see lightning and hear thunder you need to get out of the open. Off of the Lakes, off of the Golf Course etc so that you are safe. And standing under a tree is not a safe place either. Have a safe and enjoyable summer just be aware of your surroundings and keep something with you to stay updated on the weather!! II. - a powerful, violent, whirling wind produced by a . Simulator.

A. Low pressure caused by the rapid rising of air. B. It gets its gray color from water vapor condensing and from dirt and debris. Tornado C.Tornado alley - extends through Northern Texas, Oklahoma, Missouri and Kansas.

“” – “Willy Willy’s” – whirlwind in Australia

Montana County’s (number of tornadoes)

III. Hurricanes - large, swirling, low that forms over tropical waters (80oF).

A. Largest and most powerful storm B. Will become a hurricane when winds reach 120 km/h (74 mph) Classes Names Tropical Storm 39-73 mph (name) Tropical Depression 38 mph less

C. Rotates counter clockwise in the Northern Hemisphere D. As long as it's over tropical water, it will continue to have energy E. "Eye" of the Hurricane - the center of the storm a. Very calm Hurricanes F. Forms at 5° to 20° North or South Latitude Names: Atlantic – “Hurricane” Western Pacific – “” Indian Ocean – “Tropical ” Australia – “Cyclone” IV. Forecasting

A. Meteorologist - a person who studies the weather

1. "Watch" - condition are right for a severe storm

2. "Warning" - severe storm is occurring B. Weather maps 1. Station model - shows the weather conditions at one particular location

Station Model Drawing Clear - Sky Condition 680F - Temperature 600F - Dew Point S.E. - Wind Direction 25 knots - Wind Speed 1014.8 mb - Barometric Pressure 2. Isotherm - a line that connects points of equal temperature

3. Isobar - a line that connects points of equal pressure a. When isobars are close together it indicates high winds

C.Radiosonde – “weather balloon” C.Radiosonde – “weather balloon” Some facts:

In Montana, NWS Glasgow and Great Falls release these twice a day, at 4 am and 4 pm in the winter, 5 am and 5 pm when the time changes.

There are 92 stations in the that release weather balloons, all at the same time (ie. 4 pm here, or 6 pm in NYC, 3 pm in Seattle).

There's over 800 stations globally The balloon starts at a size of about 4'x4'. As it goes up, pressure decreases so the balloon is allowed to expand.

We fill our balloons up with hydrogen. That is explosive, so we have to use caution when filling them up, but it's much cheaper than helium (which is used in areas that are closer to helium reserves). (photo attached of the balloon before we fill it up and as it is filling up and when it is done).

We release the balloons, no matter the weather. Blizzards, winds over 50-60 mph, dense fog and extreme cold. Unless there's lightning, and then we have to wait until it's over before we can go and release them. The flight lasts about 2 hours

The balloon can reach 100,000 feet, or around 20 miles high

When the balloon finally bursts, it's about the size of our weather radar dome, or the size of a large two story house.

It costs about $200-$250 for each release

The balloon actually consists of a balloon, a parachute about 100 feet of string, and then the weather instrument, called a radiosonde (photo attached)

The temperature can reach as cold as -130F and winds can hit over 200 mph if the jet stream is in our region

Less than 20% of the radiosondes are returned. But, if you find one, you can pull the bag out and send it back to be reconditioned. Take out the wet cell battery that is no longer working and throw it away first. :) Just leave it in your mailbox, no postage necessary! NO NOTES V. Climate - average weather conditions over a period of at least 30 years A. Tropical climate - receives the most direct rays 0°-23° latitude B. Polar Zone - 66° to the poles C. Temperate zone - 23° to 66° latitude 1. Weather changes with the seasons D. These zones can be affected by 1. Coastal areas 2. Mountains - side facing the wind produces precipitation while the opposite side produces dry climate Go Back Go Back Go Back