The parts that make up the universe: Atmosphere- consists of the “air”…gases. Hydrosphere- consists of the “water” Lithosphere- consists of the “land” BiosphereIncludes all three!!! All organisms are found w/in the biosphere.
What is Air?It’s Got Us Covered • Air is made up of matter- it takes up space. • Air is a mixture of gases- tiny fast moving particles in motion. • Air is made up of nitrogen, oxygen, carbon dioxide, & water vapor.
Composition of the Atmosphere
Weather • Weather- The condition of the atmosphere at a certain place and time. • When talking about weather, you are actually describing what is happening in the atmosphere. • Weather is constantly changing. • Without the atmosphere, there would be no weather!
Feeling the Air • Dark colored materials heat up quicker than light colored materials. So air above dark colored surfaces heats up quicker. • When air is warmed the particles spread out. • Warm air becomes lighter & rises. The cooler air sinks. • This movement of air is called WIND.
Wind is represented by this symbol. It is called a wind barb. The barbs point in the direction from which the wind is blowing FROM.
The more “tails” there are on the barb… the stronger the wind.
The number in the bottom left corner represents the dew point. • Dew points represent the amount of moisture in the air.
The thing dividing the temperature and the dew point is called the “weather symbol”. In this case…there is fog.
The number in the right corner represents sea level pressure. We will not get into this.
Land Breeze (cool land/warm sea) Cool air over land moves out toward the water and takes the place of rising air. Warm air over the water rises. Sea Breeze (warm land/cool sea) Warm air over the land rises. Cool air over the water moves toward land and takes the place of the warmer air that has risen. Land & Sea Breezes
Weather terms you need to know… • Humidity - measure of the amount of water vapor (moisture) in the air. • Dew point - When air is cooled to the temperature at which it can hold no more water vapor, it comes together and “dew” (water droplets) form.
Precipitation - moisture coming down from the atmosphere. Rain, snow, hail, sleet (frozen rain). • Evaporation - water changing into gas…going into atmosphere. • Condensation - gas changing into water. (dew) • all three of these terms are involved in water cycle
Barometric pressure- measure of the pressure caused by Earth’s gravitational force pulling on the column of air above you. High pressure (H) - fair weather, sunshine Low pressure (L) - gray, cloudy skies and sometimes precipitation
Clouds • How do they form?? • Water vapor in the air reaches its dew point and condenses into water droplets. • Clouds are classified/named by their HEIGHT & SHAPE • Height will come 1st and shape 2nd!!! • Clouds can give us clues of upcoming weather.
Types of Clouds 3 main shapes: Cirrus Stratus Cumulus Based on height & shape… Height will come 1st and shape 2nd!!! Cirrostratus Cirrocumulus Altostratus Altocumulus Nimbostratus Stratocumulus Cumulonimbus
SHAPE: • Flat clouds = Stratus (St) • Fluffy clouds = Cumulus (Cu) • Wispy clouds = Cirrus (Ci)
HEIGHT: • Cirro- Highest clouds • Alto- Middle level clouds • Strato- Lowest clouds (usually just name of cloud with out a prefix)
Cumulonimbus = thunderstorm cloud that takes up all levels…type of cloud to form tornadoes.
What are fronts? A front is where TWO air masses meet. Changes in weather take place along a front. • Cold FrontLeading edge of colder air that is replacing warmer air. • Warm FrontLeading edge of warmer air that is replacing cooler air.
Occluded FrontWhen a cold front catches up to a warm front. Moving together. • Stationary FrontA front that is NOT moving!
http://ww2010.atmos.uiuc.edu/%28Gh%29// guides mtr/af/frnts/cfrnt/prcp.rxml
Reading weather maps… Weather maps have many things going on. You need to know and be familiar with all the symbols.
A thunderstorm is a storm with lightning AND thunder, produced by a cumulonimbus cloud, usually producing gusty winds, heavy rain and sometimes hail.
Thunderstorm Development • Thunderstorms develop in warm, moist air ahead of eastward-moving cold fronts. • Require strong updrafts and downdrafts. (vertical winds) • Weather systems (storms) move west to east!
Fun Facts about Thunderstorms: • The typical thunderstorm is 15 miles in diameter and lasts an average of 30 minutes. Nearly 1,800 thunderstorms are happening at any moment around the world. • Every thunderstorm produces lightning, (but you can’t always see it or it doesn’t touch down). It kills more people each year than tornadoes. You can estimate how many miles away a storm is by counting the number of seconds between the flash of lightning and the clap of thunder. Divide the number of seconds by five to get the distance in miles.
MYTH: If it is not raining, then there is no danger from lightning.FACT: Lightning often strikes outside of heavy rain and may occur as far as 10 miles away from any rainfall. • MYTH: The rubber soles of shoes or rubber tires on a car will protect you from being struck by lightning.FACT: Rubber-soled shoes and rubber tires provide NO protection from lightning. However, the steel frame of a hard-topped vehicle provides increased protection if you are not touching metal. Although you may be injured if lightning strikes your car, you are much safer inside a vehicle than outside. • MYTH: "Heat lightning" occurs after very hot summer days and poses no threat.FACT: What is referred to as "heat lightning" is actually lightning from a thunderstorm too far away for thunder to be heard. However, the storm may be moving in your direction!
When lightning strikes (touches the ground)….actually half came down from the bottom of cloud (stepped leader) and half came up from the ground (streamers). • Two opposite electrical charges are attracted and meet halfway…once they are connected….charges flow!!!