Atmosphere Power Point

What is Air? What is air and what is it made up of? Take 2 minutes to write down your responses. Ready, set, GO!

Does Air have Mass? Complete “Does Air have Mass?” Lab Teacher Copy: “Does Air have Mass?” Lab Sheet

Composition of the Atmosphere Earth’s atmosphere is made up of nitrogen, oxygen, carbon dioxide, water vapor, and many other gases, as well as particles of liquids and solids.

Atmosphere Blanket of gases surrounding a planet. Makes conditions on earth suitable for living things. Insulates the earth (traps energy from the sun) Protects from meteors and meteorites Protects from UV radiation

Atmosphere Con’t Not all planets have an atmosphere. Ex: Mercury doesn’t But the moon has a very thin atmosphere.

The Parts That Make Up A System Composition The Parts That Make Up A System Nitrogen - Most abundant (78%) Oxygen (21%) Argon (.93%) Carbon Dioxide (.038%) Water Vapor/particles (.032%)

Composition of the Atmosphere Nitrogen – Nitrogen is the most abundant gas in the atmosphere. It makes up more than ¾ of the atmosphere. Oxygen – Oxygen makes up less than ¼ of the atmosphere, but is the most essential for animal and human life. Oxygen is taken from the atmosphere and used to release energy from our food. Oxygen is also used in other processes like burning materials and causing rust on metals. Ozone is a form of oxygen that has three oxygen molecules instead of two. Ozone forms when lightning occurs and is what causes the smell after a storm. Around 35% of incoming energy is turned back into space by ozone layer, clouds, and dust in the air.

Composition of the Atmosphere Carbon Dioxide – Carbon dioxide is essential to life. Plants must have carbon dioxide to produce food. When humans and animals break down food to produce energy, they release carbon dioxide into the air. Carbon dioxide is also created when fuels such as coal and gasoline are burned. This increases the amount of carbon dioxide in the air. Other Gases – Oxygen and nitrogen together make up 99% of dry air. Argon and Carbon dioxide make up most of the remaining 1%

Composition of the Atmosphere Water Vapor – In reality, air is not dry and contains water vapor. Water vapor is a gas form of water. It is invisible and cannot be felt. It is not the same thing as steam. The amount of water vapor in the air varies greatly from place to place and time to time. We sometimes call water vapor humidity. Water vapor is what eventually forms clouds and precipitation. Particles – Precipitation cannot form without particles in the air. Our air contains tiny particles of dust, smoke, salt, and other chemicals. Most of these particles are too tiny to see.

Video Clip United Streaming: http://app.discoveryeducation.com/search ?Ntt=Earth%27s+Atmosphere%3A+The+P roperties+of+the+Atmosphere+

Review Questions What is the atmosphere? A thin layer of gases that surround Earth What are the four most common gases in dry air? Nitrogen, Oxygen, Carbon dioxide, and argon Why are the amounts of gases in the atmosphere usually shown as percentages of dry air? The percentage of water vapor in the air varies and affects the percent composition. What are three ways in which the atmosphere is important to life on Earth? It contains oxygen need by many organisms. It provides warmth by trapping energy from the sun. It protects us from dangerous radiation and objects from outer space.

Properties of Air Air is made up of atoms and molecules, which have mass. This means that air also has mass. Because air has mass, it also has other properties including density and pressure. Density – The amount of mass in a given volume of air is its density. # of molecules in the same amount of space. If there are more molecules in a volume, the density is greater. If there are less molecules in a volume, the density is less Density = Mass Volume

Properties of Air Air pressure can change from day to day just like the amount of water vapor in air. Air pressure is related to density and mass: The more dense a substance, the more mass and pressure it has.

Air Pressure There is a column of air above you all the time pushing on us all the time. The weight of the air in the atmosphere causes air pressure. Miles of air above us weight a lot. 15 pounds of pressure on every square inch of your body. Moist air is lighter than dry air. Pressure decreases as the amount of moisture in air increases. “Pressurized” airplanes (Impossible to breathe without making it similar to the pressure on the ground).

Measuring Air Pressure Barometer – A barometer is an instrument that is used to measure air pressure. There are two common kinds: mercury and aneroid Air pressure is measured using several different units. We will learn about 2 of those. Inches of mercury – This is the most common form used in everyday weather forecasts. The meteorologist might say – “The pressure reading today is at 30.75 inches.” Millibars – The National Weather Service maps use millibars to measure air pressure. 1 inch of mercury = 33.87 millibars, so 30 inches of mercury = 1,016 millibars

Measuring Air Pressure – Mercury Barometer Air pressure pushes down on the surface of the mercury in the dish, causing the mercury in the tube to rise. The air pressure is greater on the barometer on the right, so the mercury is higher in the tube.

Measuring Air Pressure This diagram shows an aneroid barometer. Changes in air pressure cause the walls of the airtight metal chamber to flex in and out. The needle on the dial indicates the air pressure.

Warm UP When referring to UV radiation, what does the “UV” stand for? Where does UV radiation come from? What could happen if you are exposed to too much UV radiation? What might protect us from radiation?

Air Pressure and Altitude Air pressure decreases as altitude increases. Altitude is your elevation, or height above sea level on earth. The higher up you go, the lower the Pressure and density. The lower you go, the higher the pressure.

Altitude and Density The density of air decreases as altitude increases. Air at sea level has more gas molecules in each cubic meter than air at the top of a mountain. Since Air is less dense at high altitudes, there are fewer oxygen molecules, so you would become short of breath quickly at high altitudes.

Video Clip: Density and Pressure United Streaming Video: http://app.discoveryeducation.com/searc h?Ntt=Matter+and+Energy%3A+Chapte r+2%3A+Pressure+%5B09%3A18%5D Atmosphere website

Layers of the Atmosphere The Air Up There Exosphere Ionosphere Thermosphere Mesosphere Stratosphere Troposphere

Layers of the Atmosphere There are four layers of the atmosphere: based on Temperature and density. -Troposphere -Stratosphere -Mesosphere -Thermosphere - Ionosphere - Exosphere

The Troposphere Lowest layer & Closet to Earth Contains most of the mass of the atmosphere Weather occurs here 9-16 kilometers in depth Temperatures decreases as altitude increases Layer where airplanes fly here and where we live and breath in, weather, pollution, birds, and Water Vapor.

The Stratosphere Begins where troposphere ends and goes about 50 km above Earth Increase temp with altitude Divided into lower, middle and, upper sections Lower section is cold, -60 degrees Celsius Middle section is the ozone layer (protects us from harmful ultraviolet radiation from the sun. Upper section is warm due to ozone absorbing energy from the sun and converts it into heat. Absorbs UV Radiation- Need Sunscreen This is where planes fly because it is above the weather and jets fly in this layer too. Pollutants that reach the lower area may linger for lengthy periods. Ex: Volcanic eruptions can cause changes in the weather and climate

The Mesosphere Middle layer – (meso means middle) Located between 50-90km above the Earth’s surface No concentrated O3 Outer mesosphere is the coldest part of the atmosphere and has a temperature of -90°C The Mesosphere is where meteoroids burn up and it protects us from them. When you see a shooting star, you are seeing the trail of a burning up meteoroid.

The Thermosphere Located 90+km above the Earth’s surface and Warmest Layer (“Thermo”) No definite outer limit and extends out to space Very hot (1,800 degrees Celsius) because sunlight hits the thermosphere first. Least Dense-does not feel hot to humans (So spread apart we could deal with it) It is divided into to parts: Ionosphere (lower layer) aurora Borealis Exosphere (upper layer) outer layer

Ionosphere The lower layer of the thermosphere Located 80-400km above Earth Radio waves bounce off ions in the ionosphere back to Earth’s surface. The aurora borealis is found here. This is caused by particles from the sun that strike atoms in the ionosphere and causes them to glow.

Exosphere Begins at about 400km and extends out into space – no clear boundary Fewer and fewer molecules with altitude Contains light gases like hydrogen and helium Satellites and the space shuttle both orbit in the exosphere.

Need to know Prefixes Sphere – round Tropo – changing (weather is always changing here ) Strato – spread out (thinning out) Meso – middle Thermo – heat Exo - outer

Good and Bad Ozone Good Ozone:( Stratospheric Ozone) – Shields us from the suns UV rays. It is found 10-30 miles above earth’s surface in the stratosphere. Bad Ozone: (Tropospheric ozone) – Found in the lower atmosphere, near the ground, is formed by cars, power plants, chemical plants and other sources that react in the presence of sunlight. It is greater concern in areas with higher temperatures and higher pollution.

Who is at the highest risk for damage from the ozone? Children spend time outside (a lot) in the summer. Anyone who has asthma or other respiratory disorders. Adults of all ages who work vigorously outside. Ozone is like sunburn for the lungs. The only difference is that the lungs have no nerves. So you can’t feel the pain.

Warm Up (True or False) If false write the correct answer We live in the troposphere. Radio Waves bounce off of the ionosphere. There are 7 main layers of the atmosphere. The exosphere is commonly called space. All weather occurs in the stratosphere. The hottest layer of the atmosphere is the troposphere. The mesosphere is the coldest layer of the atmosphere. The ozone is found in the thermosphere. The most abundant gas in the atmosphere is oxygen.

Temperature Vs Altitude

Air Quailty Tells us the levels of pollutants in the air. Pollutants are harmful substances found in the air (as well as water and soil). Pollutants can affect the health of humans and animals.

Sources of Pollution Point Source – pollution can be traced to a single source (factory, oil refinery). Nonpoint Source – can not be traced to a specific point or location (farm run-off, storm water run-off).

Sources of Pollution Natural sources – Fires, soil, dust, pollen, volcanic ash. Human Activities – Burning fossil fuels, farming, construction.

Smog and Acid Rain Smog – (smoke and fog) results from burning high amounts of coal. Acid Rain - is rain or any other form of precipitation that is unusually acidic.

EPA Environmental Protection Agency – Agency of the USA. Mission is to protect human health and the environment. Develop and enforce environmental regulations. Performs and finances environmental research.

Layers of The Atmosphere Project Guidelines: *Have your science journal out. I will come around and check them.* Layers of The Atmosphere Project Guidelines: #1: Every Layer should be labeled. Even the ionosphere, exosphere, and ozone layer. #2:Every Layer should have at least 3 or more characteristics written about them. #3: Every layer should have pictures of objects that may be found in that layer. #4: Make your foldable colorful and put as much information as you would like on it. You will be using this to study for tests/quizzes.