earth’s atmosphere science... · web viewthere are two types of barometers commonly used today,...

Name: ______________________Meteorology - Earth's Atmosphere Notes

Earth’s Atmosphere is:__________________________________________________________

Gas Composition of Earth’s atmosphere:

21% ___________________ 78% ___________________ 0.04% ___________________ ~0.9% ___________________

Formation of the Atmosphere: Volcanoes sent out gases to create the early atmosphere. These gases were.

CARBON _____________ _______________ (H2O vapor), ____________ and _____________

There was NO _______________.

Earth’s atmosphere:1

(From the ground out to space.)

Troposphere: The Layer closest to Earth

- What happens in this layer? _________________________________________

- What happens to the temperature and pressure as you go up in elevation?

- __________________________________________Stratosphere ______________________________________________



- __________________________________________

Mesosphere ________________________________________________



- __________________________________________

Thermosphere _______________________________________________



- __________________________________________

* Ionosphere made of electronically charged particles.2

____________________________________ o In the daytime this layer interferes with radio

waves since suns energy charges the particles to much and causes problems a lot of static.

o At night it is less charged. This is why it is easier to hear AM radio late at night.

Exosphere _____________________________________________________



- __________________________________________

Air Pressure – MeasurementAir pressure is the force exerted on you by the weight of tiny particles of air (air molecules). Although air molecules are invisible, they still have weight and take up space. Since there's a lot of "empty" space between air molecules, air can be compressed to fit in a smaller volume.

Air Pressure:At sea level, the air pressure is about 14.7 pounds per square inch. As your altitude

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increases (for example, if you climb a mountain), the air pressure decreases. At an altitude of 10,000 feet, the air pressure is 10 pound per square inch (and there is less oxygen to breathe).

Measurement of air pressure:Millibar:

Small _____________________________________________________________

1013.25mb = is the average sea level air pressure. 34 millibars = 1 inch of mercury. 1 millibar = 1/1000 of a bar 1 bar = 100,000 newtons 1 newton is forced it takes to move an object of 1kg at a rate of 1 meter per

second.

Isobars:The lines __________________________________________________________.

Barometer: - __________________________________________________

A barometer is a device that measures air (barometric) pressure. _______

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_______________________________________________ _________________________. There are two types of barometers commonly used today, mercury and aneroid (meaning "fluidless"). Earlier water barometers (also known as "storm glasses") date from the 17th century. The mercury barometer was invented by the Italian physicist Evangelista Torricelli (1608 - 1647), a pupil of Galileo, in 1643. Torricelli inverted a glass tube filled with mercury into another container of mercury; the mercury in the tube "weighs" the air in the atmosphere above the tube. The aneroid barometer (using a spring balance instead of a liquid) was invented by the French scientist Lucien Vidie in 1843.

2 types used _________________________ _________________________

Aneroid Barometer:____________________________________________________

________________________________________________________________________________________________________________________________________________________________________________________________________________

Vacuum: air removed

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Toricelli Mercury Barometer:A Glass ________________________________________________________________________________________________________________________________________________________________________

The height that the mercury rises in the glass tube is directly related to the atmospheric pressure. This pressure is usually measured in inches of mercury. A standard mercury barometer has a glass column about 30 inches long. A measurement of 29.92 inches of mercury is equivalent to 1013.25 millibars.

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Atmospheric pressure at the Earth's surface is one of the keys to weather High and low are pressure are important because they affect the weather.

A "high" is an area __________________________________ ________________________________________________.

A "low' is where _____________________________________ _________________________________________________; it's the relative differences that count.The pressure is high at the surface where air is slowly descending - much to slowly to feel. And, this is going on over a large area, maybe a few hundred square miles. As air descends, it warms, which inhibits the formation of clouds. This is why high pressure is generally - but not quite always - associated with good weather.The air that descends in high-pressure areas has to get to high altitudes in some way, and that way is _________________________________________________________________________________________________.

As air rises it cools. As the air cools, the humidity in it begins to ___________________________________________, or if it's cold enough, into tiny ice crystals. If there is enough water, or ice, rain or snow begin to fall. This is why low pressure is associated with bad weather.

As shown in the graphic above, the air descending in high pressure flows out in a clockwise spiral in the Northern Hemisphere. Air flowing into an

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area of low pressure to rise, makes a counterclockwise spiral on the way in.

Air pressure can tell us about what kind of weather to expect as well. If a high pressure system is on its way, you can expect cooler temperatures and clear skies. If a low pressure system is coming, then ______________________

_____________________________________ .

Low Pressure Troughs: What is it?____________________________________________

____________________________________________

_________________________________

________________________________.

Sometimes, a trough may be a region between two high pressure centers and there is not a low pressure center. In this case, it is still represented by a line between the two high pressure centers.

Cold Front: What is it? At the cold front, the cold air cuts underneath the warm air and forces the warm air up a much steeper angle.

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____________________________________

____________________________________

____________________________________

These produce heavy rain, snow & precipitation

Wind: What makes it blow?____________________________________________________________________________________. These areas of high and low pressure are created from temperature differences caused by the sun heating the earth, which in turn heats, theatmosphere.

Pressure gradient force:____________________________________________________________

-so-The lower the _________________________________________________________.

Coriolis Effect:The force due to the Earth's rotation that cause objects in motion to ________________

_________________ the Northern Hemisphere and to the ______________ in the Southern Hemisphere.

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Planetary Winds:Hypothetical look ofplanetary wind on

planet if:

Source: website of the National Weather Service, Southern Regional Headquarters - US

1) ______________________

________________________

2) No rotation of the _____

_______________________

_______________________

North

EquatorWarm Temp and air

Cooler Temp and air

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Sout

Cooler Temp and air

60

30

30

60

North PoleFalling Cold Dry Air

Equator

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Global Wind Patterns: Winds named for the direction they come from

"Special" surface wind zonesDoldrums - an area of low-pressure occurring __________________________________. Winds here are usually calm or very light and so ships would avoid the area because they would only be pushed along very slowly.

ITCZ - The easterly trade winds of both hemispheres ____________________________________________ called the "Intertropical Convergence Zone (ITCZ)

Horse Latitudes - These are located mostly over the oceans, at about 30° latitude in both of the hemispheres. Stories say that sailors gave the region of the subtropical high the name "horse latitudes" because ships _______________________________________________________; fearful of running out of food and water, sailors threw their horses and cattle overboard to save on provisions.

Surface wind bands on EarthTrade Winds - These are found from __________________ latitude (aka Tropical Easterlies)Prevailing Westerlies - These are found from the __________________ latitude (aka Westerlies).Polar Easterlies - These are found from the __________________ latitude.

Different Kinds of Wind across the surface:

Sea (large open water) Breeze onto Land:

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A sea-breeze (or onshore breeze) is a _________________________________________________________________wind from the sea that develops over land. It is formed by increasing temperature differences between the land and water, which create a pressure low over the land due to its relative warmth and forces higher pressure, cooler air from the sea to blow onto the land.

Source: http://en.wikipedia.org/wiki/Sea_breeze

Land Breeze from sea or a Lake

At night, the ____________________________________________ water, which forces the dying of the daytime sea breeze. If the land cools below that of the adjacent open water, the pressure over the water will be lower than that of the land. This creates a land breeze flowing back out towards the open water. Source: http://en.wikipedia.org/wiki/Sea_breeze#Land_Breeze

Valley Breeze: (occurs mainly in afternoons)

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A wind formed during the day by the _________________________________. As the ground becomes warmer than the surrounding atmosphere, the lower levels of air heat and _________, flowing up the mountainsides. As the warm air rises and cools over the mountains clouds may form from the warm moist air condensing. This is also known as an anabatic wind. Source: http://www.weather.com/glossary/v.html

Mountain Breeze: (occurs evenings and night)

This wind is formed at night by the radiational cooling along mountainsides. As the ___________________________ than the surrounding atmosphere, the air closest to the mountainside cools and drains drains down into the valley. This wind is known as a Katabatic Wind. Source: http://www.weather.com/glossary/m.html#mtnbrz

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ANABATIC WIND - A Wind that ________________________________________________.

KATABATIC WIND - A wind that is created ______________________________.

Chinook Wind – A Chinook is produced _______________________________. As air down slopes it warms adiabatically and decreases in relative humidity. The Chinook is common in the northern plains of the United States in winter. Source: http://www.theweatherprediction.com/wind/

“In popular myth, Chinook is supposed to mean "snow eater", as a strong Chinook can make a foot of snow all but vanish inside of one day. The

snow partially melts, and partially evaporates in the dry wind. However, the true origin of the name is that "Chinook Wind" in the local language of

the fur traders meant that the wind came from the direction of the country of the Chinooks (the lower Columbia River, i.e. from across the

Rocky Mountains).” Source http://en.wikipedia.org/wiki/Chinook_wind

Fog: What is it and how does it form?16

Fog is a cloud that touches the ground. It is ______________________

_______________________________________________________. Fog forms when the air at ground level is cooled enough to reach its saturation point. This is also known as Relative Humidity that equals 100%. Source: http://www.physicalgeography.net/fundamentals/8f.html

Relative Humidity: The amount of water vapor in the air at any given time is usually less than that required to saturate the air. The relative humidity is the percent of saturation humidity. The saturation humidity is when no further water can be held in a gaseous state. 1) First, the ______________________________________________________ “hold."

2) Dew point is a ________________________________________ is actually in the air.

3) Relative humidity is a measure of the amount of water in the air compared with the amount of water the air can hold at the temperature it happens to be when you measure it. Source: http://www.usatoday.com/weather/wrelhum.htm Jack Williams USAToday.com

- Types of Fog -Radiation or Ground Fog is relatively shallow fog. Radiation fog is also known as ground fog. It is produced near the ground. It is formed by the cooling of _________________________ by thermal (infrared) radiation in calm conditions with a clear sky. The cool ground produces condensation in the nearby air by heat conduction.

Upslope FogUpslope fog forms when winds ________________________________. This flow upwards causes the warm air to cool as it rises, which causes the moisture in it to condense and form fog.

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Valley FogValley fog forms in mountain valleys, often during the fall, winter and early spring. It is the _________________________________ caused by heavier cold air settling into in a valley, with warmer air passing over the mountains above. It is essentially radiation fog confined by local topography, and can last for several days in calm conditions.

Advection fogAdvection fog is created when ____________________________, and the air is cooled. As the air is cooled it reaches its relative humidity saturation point and fog is formed. This kind of fog is common as a

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warm front passes over an area with significant snow pack. Source: http://en.wikipedia.org/wiki/Fog

Evaporation FogEvaporation Fog is a specific type of advection fog. It occurs when you get cold air advancing ______________________________________________. In this situation, fog forms as water from the surface evaporates into the cold air and then saturates Source: http://www.physicalgeography.net/fundamentals/8f.html

1) Cold air off of land flows out over water. 2) Formation of evaporation fog3) Warm water ocean/lake surface

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earth’s atmosphere science... · web viewthere are two types of barometers commonly used today,...

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