The Atmosphere. The Atmosphere. The atmosphere is a mixture of gases that surrounds a planet, such as Earth. Nitrogen, oxygen, carbon dioxide, and other gases are all parts of this mixture.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Temporary behavior of atmosphere (what’s going on at any certain time)
Small geographic area
Can change rapidly
Long-term behavior of atmosphere (100+ years)
Large geographic area
Very slow to change
Body of air with a certain temperature and moisture level
As it moves, the characteristics of an air mass change and so does the weather.
Can be warm(T) or cold(P)
Can contain a lot of moisture(m) or not a lot of moisture(c)
Named according to their source region.
Ex: cP, mT
places where air masses meet
4 Types: Warm, Cold, Occluded, Stationary
Each kind can bring different kinds of weather
Cold Front – cold, dense air moves into a region occupied by warmer air, leads to heavy downpours and gusty winds
Warm Front – warm air moves into an area occupied by cooler air, Brings warmer temperatures and precipitation,
Stationary Front – flow of air is neither toward cold or warm air mass
Occluded Front – an active cold front takes overtakes a warm front; complex weather pattern
Pressure exerted by weight of air above it. Exerted in ALL directions
Measured with a BAROMETER
If it CHANGES, then new weather is on the way:
Falling Air Pressure = stormy weather coming
Rising Air Pressure = fair weather coming
Steady Air Pressure = no change is coming
Moves from areas of HIGH to LOW pressure
Greater the difference in pressure, the FASTER the wind blows
Labeled from which direction they blow
Cyclones – centers of low pressure; pressure decreases from outer isobars toward the center.
Anticyclones – centers of high pressure; pressure increases from outside toward center
Thunderstorms – form when warm, humid air rises in an unstable environment; produce gusty winds and heavy precipitation
Tornadoes – violent windstorms that take the form of a rotating column of air called a vortex. Vortex extends downward from a cumulonimbus cloud.
U.S. -770 per year; most form in association with severe thunderstorms
Hurricane – a whirling tropical cyclone that produces wind of at least 119 km/h; most powerful severe storm; develops when water temps. are warm enough to provide the necessary heat and moisture in the air
Humidity – amount of water vapor in the air
Controlled by temperature
1. Warm air holds more moisture than cool air (more space for water vapor between air molecules)
2. As air warms, relative humidity decreases
3. As air cools, relative humidity increases
Measure of the amount of moisture in the air compared to what the air could hold
How “full” of water the air is
Expressed as %
100% relative humidity = saturated air
Air pollution Global warming
Acid rain Ozone Damage
Human activity produces two main types of air pollutant:
Air pollution has been a major problem since the Industrial Revolution of the late 18th Century, and has been made worse by humans’ reliance on burning fossil fuels for energy.
Air pollution, global warming, acid rain, damage to the ozone layer and smog. Each of these has serious implications for the environment and human health.
One of the greatest threats caused by air pollution is global warming. Global warming is caused by a build-up of greenhouses gases, which leads to an increase in the Earth’s temperature. Other effects include bizarre weather patterns, and melting of polar ice caps
Key greenhouses gases include:
Smog is a mixture of air pollutants and particulates that is sometimes found in the lower levels of the atmosphere. It has a distinctive brownish haze.
Smog can reach dangerous levels in built-up areas, causing irritation to the eyes and lungs.