The Atmosphere Grade 10 2012

Atmosphere Immediate layer of air that envelopes Earth Made up of gases, essential to life The gases: Acts as a screen, blocking out UV rays and other dangerous rays from the sun Allow for heat retention Include Oxygen (cellular respiration) and Carbon Dioxide (photosynthesis)

Composition of Air There are many different types of gasses in the atmosphere They include nitrogen, oxygen, argon, carbon dioxide and other noble gasses The gas that is most abundant is nitrogen

Think of the Atmosphere like a Hamburger… Bun Mayonnaise Lettuce Tomato The typical hamburger might look like this: bun, hamburger meat, tomato, lettuce, mayonnaise and bun. Hamburger Bun

Layers Today we will study atmospheric layers and we will see that the atmosphere is in layers much like the layers on a hamburger. Atmosphere-

Layers of the atmosphere There are 4 layers in the atmosphere They are the troposphere, stratosphere, mesosphere and thermosphere

Exosphere Thermosphere Mesosphere Stratosphere Troposphere Earth Name The Different Layers as they come in, also explain that the Exosphere is not really a layer but is the beginning of outer space. Troposphere Earth

Troposphere 0-15 km Cloud formation Storm activity Higher the altitude, the lower the temperature Every 1000m the temperature drops 6.5o C

Stratosphere This layer sits on top of the troposphere This layer contains the ozone layer, which protects us from harmful sunlight

Stratosphere 15-50 km UV rays absorbed Contains the ozone layer, presence of ozone gas Temperature increase with altitude Air particles are increasingly rare

Mesosphere 50-80 km Coldest layer of our atmosphere As altitude increases temperatures decrease Temperatures hover -80o C Human would survive merely minutues due to lack of air particles

Thermosphere This is the highest layer of the atmosphere It’s height ranges from 100 to 400 km This is where most small meteorites burn up and is also the location in the atmosphere that the northern lights occur (aurora borealis)

Thermosphere 80-500 km from earth’s surface Absorbs the majority of the suns rays Hottest layer of the atmosphere, temperatures as high as 1800o C Celestial bodies(meteors) that come in contact with thermosphere burn rapidly Shooting stars Polar auroras usually form this layer

Atmospheric Pressure Air is a gas, therefore air is a compressible fluid. It can exert pressure because it contains particles that are constantly colliding with one another At sea level the average atmospheric pressure is 101.3 kPa

Atmospheric Pressure 2 Main factors affect atmospheric pressure Number of particles When the number of particles increases, they collide more frequently and the pressure rises When the number of particles drops, the pressure falls. 2. Temperature of air When air warms its particles move more rapidly and therefore collide more frequently You would think this would cause pressure top rise…. In the atmosphere, it doesn’t because particles have room to move and spread apart… the DENSITY of air drops WARM AIR IS LIGHTER THAN COLD AIR

Air Masses Anticyclones and Depressions

Air Masses An air mass is a defined as a large body of air with very similar characteristics. Generally speaking, air masses are generally defined by temperature and moisture Air masses are named based on the source region of the air mass itself

Types of Air Masses Continental Polar, “cold and dry” Originates closer to the Poles over land- locked regions. Continental Tropical, “warm and dry” Originates closer to the Tropics over land-locked regions. Maritime Polar, “cold and damp” Originates closer to the Poles over water. Maritime Tropical, “warm and humid” Originates closer to the Tropics over water. Arctic, “very cold” Originates in the very cold land-locked areas

Warm and Cold Fronts Fronts are the dividing line between air masses so understanding air masses, means understanding where fronts are located

Types of Fronts Cold Warm Noted by cold air advancing and displacing warmer air that exists. Warm Noted by cold air retreating from an area.

Cold Front Marked on a map with a blue line and blue triangles pointing towards the warm air. Associated with cumulus & cumulonimbus clouds ahead of the front in the warm air, producing showers and thunderstorms.

Cold Front Simple 3-D idea: http://www.physicalgeography.net/fundamentals/7r.html

Cold Front http://www.free-online-private-pilot-ground-school.com/images/cold-front.gif

Warm Front Marked on a map by a red line with red semi-circles pointed towards the cool air (in the direction the warm air is retreating to.) Generally associated with stratus type clouds, overcast skies, fog, and general rain or snow.

Warm Front Simple 3-D idea: http://www.physicalgeography.net/fundamentals/7r.html

Warm Front http://www.free-online-private-pilot-ground-school.com/images/warm-front.gif

THE Greenhouse Effect Earth and Space Grade 10 2012

Hook http://www.youtube.com/watch?v=_Zo7wTO dc_M&feature=related

GreenHouse Effect Sunlight heats the Earth The warm Earth radiates energy (in the form of infrared radiation, or heat) back out Some of this infrared radiation is trapped in the atmosphere, giving Earth its temperate climate THIS= Greenhouse effect

Greenhouse effect Without it, our climate would be harsh and severe like on the moon The greenhouse effect is very similar to a car on warm summer’s day, the heat gets trapped inside the car making it scorching HOT!!

Selected Greenhouse Gases Carbon Dioxide (CO2) Source: Fossil fuel burning(cars, factories), deforestation Average atmospheric residence time: 500 years Carbon Dioxide is not dangerous itself, but too much of it has a profound effect Methane (CH4) Source: Rice cultivation, cattle & sheep ranching, decay from landfills, mining Average atmospheric residence time: 7-10 years Nitrous oxide (N2O) Source: Industry and agriculture (fertilizers) Average atmospheric residence time: 140-190 years Water Vapor (H2O) Source: Rain and Oceans

Global Warming, A Quick Poll Is global warming real? Yes No How much has the average temperature of the Earth risen in the last 100 years? ~ 0.5°C ~ 1.0°C ~ 5.0°C ~ 10.0°C This is the highest temperature ever recorded in Earth’s history. Yes. No. Who is to blame? Human activities Nature causes ET NoCanTell! What is to blame? Ozone CO2 H2O O2

Global Warming, A Quick Poll Who is to blame? Human activities Nature causes ET NoCanTell! What is to blame? Ozone CO2 H2O O2 NoCanTell. It is real complicated! Is global warming real? Yes No How much has the average temperature of the Earth risen in the last 100 years? ~ 0.5°C ~ 1.0°C ~ 5.0°C ~ 10.0°C As far as we know, this is the highest temperature ever recorded in Earth’s history. Yes. No.

Global Warming VS Greenhouse Effect The greenhouse effect & global warming are not the same thing. Global warming refers to a rise in the temperature of the surface of the earth An increase in the concentration of greenhouse gases leads to an increase in the magnitude of the greenhouse effect. (Intensification) This results in global warming

Average global Temperature and Carbon Dioxide Concentrations

What is causing this Intensification? The balance of CO2 we are used to experiencing, has unbalanced over the last 20-30 years CO2 mainly came from forest fires, volcanic activity, and cellular respiration The oceans and plants(photosynthesis) were able to absorb the level of emmissions = stable temperatures! NO MORE….

What is causing this Intensification? Population Growth is the main cause for the extra CO2 we are experiencing in our environment. More cars More energy use in homes Bigger factories

Why is the extra CO2 so bad? Global warming! Rise in tides Heavy drought Spread of disease Climate Change Endangered species Think Arctic warming

Extra N2O and ch4 Excessive methane causes a greenhouse effect 21 times greater than CO2 Sources: farm animal digestion, manure storage, rice farming, decomposing household waste Excessive Nitrous Oxide also emphasizes the greenhouse effect Primary Source: Fertilizers

Runaway Greenhouse Effect If we were to move the Earth closer to the Sun, like where Venus is now, then we would suffer the runaway greenhouse effect as well, lose all the water, and become hot like Venus.

Tim and Moby Review http://www.brainpop.com/science/earthsyst em/greenhouseeffect/preview.weml

Energy Resources in the Atmosphere Earth and Space Grade 10 2012

What are wind turbines? Wind turbines can transform the kinetic energy of the wind into electrical energy Wind is a renewable source of energy (environmentally friendly)

How Do Wind Turbines Work? http://www.aniboom.com/animation-video/339613/How-Wind-Turbine-Work-By-Yonatan-Frimer/

Disadvantages to Wind Energy Wind is not always reliable Expensive to set up Eye sore- some people find they ruin the natural landscape

The effect of the sun and moon

Solar radiation The sun is a star. It is composed of 75% hydrogen and 25% helium. The extreme temperature of the sun (15 000 000oC) produces nuclear energy, i.e. hydrogen atoms combine to form helium, releasing large amounts of energy. The sun emits radiation of all spectrum wavelengths but only visible light, infrared rays and ultraviolet rays reach the earth.

Solar Energy We can use the energy in the Sun’s radiation. There are a few ways to do this.

Solar Energy Solar collectors Used as a source of heat Copper tubing is placed underneath glass panels Used mainly to heat water for homes or swimming pools

Solar Energy Photovoltaic Cells Used as a source of electricity Large panels are made of silicon cells. When they are hit by light, electrons move and a current is created Can be used as a source of electricity in homes and buildings. They also prove to be very useful in space.

The Earth- Moon System Tides A tide is a rise and fall of water in the sea or ocean. Tides are caused by the Moon’s gravitational pull. The water is pulled by the Moon’s gravitational attraction and as a result, bulges of water are formed on each side of the earth. Those regions experience high tide. Brainpop.com (moon and tides)

Tides The moon pulls water toward it, and this causes the bulge toward the moon. The bulge on the side of the Earth opposite the moon is caused by the moon "pulling the Earth away" from the water on that side.

Tides There are 2 high tides and two low tides each day.

Tidal Energy Tidal energy is obtained from the rise and fall of the tides. Tidal energy can be transformed into electrical energy. The process used to transforms tidal energy is similar to producing hydroelectricity.