Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
34 Cards in this Set
- Front
- Back
|
Original atmosphere |
Primarily helium and hydrogen destroyed by the solar wind of the sun. |
|
|
Second atmosphere |
Formed 4.4 billion years ago Contained mainly Carbon Dioxide and water vapor with some nitrogen and no oxygen.100 times more gas than current atmosphere.Carbon dioxide was dissolved in the seas and created carbonates. |
|
|
About 3.3 million years ago the first oxygen producing organisms (cyanobacteria) appeared. |
Responsible for adding oxygen to the atmosphere.Ozone was formed and provided protection to organisms from the ultraviolet radiation.Nitrogen levels started to increase from the breakdown of ammonia by sunlight and bacteria. |
|
|
Third atmosphere |
Was formed 200-250 million years ago and evolved to the current atmosphere. |
|
|
Nitrogen |
78%Needed to produce proteinReturned to the atmosphere by the decaying of plants and animals |
|
|
Oxygen |
21%Needed for respiration and combustionReturned to the atmosphere |
|
|
Carbon Dioxide |
Small amount found in atmosphereUsed by plants to make food photosynthesisReturned to the atmosphere by the respiration of plants and animals Water VaporPlays an important role in earth’s weather |
|
|
Ozone |
Made up of 3 oxygen moleculesProtects us from ultraviolet radiation |
|
|
Dust Particles |
needed for water vapor to condense |
|
|
Atmospheric Pressure |
The force exerted on a surface by the weight of the air above that surface. |
|
|
99% of the total mass of atmospheric gases is found within 32 km of the surface 1 cm column of air, at sea level, has a mass of 1.03 kg or 2 lbs. (14.7 pounds per square inch at sea level) |
Atmospheric pressure decreases as altitude increases.Air Pressure is equal in all directionsAtmospheric pressure is depended upon the density of air |
|
|
Measuring Atmospheric Pressure |
Units used to measure pressure are inches, centimeters, and millibars |
|
|
Lowest in inches, centimeters, and or millibars |
the Lowest was 25.69 inches |
|
|
Highest in inches, centimeters, and or millibars |
Highest sea level pressure was 32.06 inches |
|
|
Factors that affect air pressure/ Density |
Water Vapor Temperature Elevation |
|
|
How does water vapor affect air pressure? |
Large amounts of water vapor cause lower air pressure |
|
|
How does temperature affect air pressure? |
Warmer is less dense, causing lower ai pressure |
|
|
How does elevation affect air pressure? |
Air becomes less dense(thinner) at higher altitudes causing lower air pressure |
|
|
Types of air pressure |
Low Pressure High Pressure |
|
|
What is high pressure? |
Cool and dry air Rotate Clockwise Clear and sunny weather |
|
|
What is low pressure? |
Warmer air and humid air Rotate Counter-clockwise Inclement weather |
|
|
Barometer |
Instrument used to measure air pressure |
|
|
Mercurial Barometer |
Consists of a glass column standing in a well of mercury. As air pushes down on the mercury, the height of the mercury will rise or fall in the glass column |
|
|
Aneroid Barometer |
Consist of sealed metal container free of air. As air pressure changes, the container expands or contracts. A moving pointer on a scale indicates these changes.Increased air pressure causes the container to bend in.This is the most common type of barometer |
|
|
Wind |
Air in motion movement from one point to another |
|
|
What direction does wind Travel in? |
High to low |
|
|
Wind Characteristics. |
Causes Changes in atmospheric pressure Movement Air flows from high pressure to low pressure High pressure air is cool and denseLow pressure air is warm and less dense |
|
|
Naming of Winds |
Winds are named according to the direction they come from |
|
|
Measuring and Detecting Winds |
Wind vane: points to where the wind is coming fromWind Speed Anemometer: Measures speed in mph or knots |
|
|
Types of Atmospheres |
Ionosphere Exosphere Mesosphere Ozone |
|
|
Ionosphere |
Lower region of thermospherere flects radio waves |
|
|
Exosphere |
upper region of thermosphere |
|
|
Mesosphere |
coldest layer |
|
|
Ozone |
made of 3 molecules of oxygen |
