The Atmosphere

1. The Atmosphere

2. WALT: about the Earth‘s Atmosphere

3. The Atmosphere: Die Atmosphäre • The Earth‘s atmosphere is a thin layer of gases that surround the Earth. • The layer of gas stays there due to gravity. • The atmosphere has several important jobs;

4. The Atmosphere: Die Atmosphäre • The atmosphere has several important jobs; • It insulates the Earth from extreme temperatures. • It keeps heat inside the atmosphere. • It blocks harmful radiation from the sun.

5. The Atmosphere: Die Atmosphäre • The atmosphere has a mass of about 5 quintillion kg. • Three quarters of which is within the first 11km. • The atmosphere becomes thinner the higher up you go. • At 100 – 120 km up is roughly the boundry between our atmosphere and outerspace.

6. 650 - 10,000 km Particles very spread out Mainly hydrogen and helium SPACE 85 – 650 km Temperatures increase as you go up to 1,500ºC Space station orbits at 350 km 50 – 80 km Temperature decreases quickly as you go up. Meteors 17 – 50 km Temperature increases as you go up. Ozone layer is at about 25km ATMOSPHERE 7 – 17 km The weather and clouds occur in this part. Temperature decreases as you go up.

7. Atmosphere quiz • What is the name of the layer of the atmosphere that is closest to the earth? • In which layer does the space station orbit. • Why do we need the atmosphere (4 reasons)? • What was the most interesting thing you learn today? 

8. Evolution of the Earth’s Atmosphere Volcanic activity releases CO2, methane, ammonia and water vapour into the atmosphere. The water vapour condenses to form oceans. 4 Billion years 3 Billion years 2 Billion years 1 Billion years Present day Green plants evolve which take in CO2 and give out oxygen. Carbon from CO2 becomes locked up in sedimentary rocks as carbonates and fossil fuels. Methane and ammonia react with the oxygen and nitrogen is released. Nitrogen is also produced as a result of denitrifying bacteria on nitrates from decaying plants. Some of the oxygen is converted into ozone. The ozone layer blocks out harmful ultra-violet rays which allows for the development of new life.

9. Carbon Methane Ammonia Oxygen Nitrogen Others dioxide 4 Billion years 3 Billion years 2 Billion years 1 Billion years Present day Evolution of the Earth’s Atmosphere Present day atmosphere contains 78% nitrogen, 21% oxygen, 1% noble gases and about 0.03% CO2

10. The Ozone Layer • Ozone is oxygen that contains molecules that have 3 oxygen atoms (O3). • There is a layer of ozone high up in the atmosphere which shields the Earth from the sun's harmful UV rays, these rays can lead to an increase in skin cancer. • In the 1980’s concentrations of ozone appeared to be dropping in certain areas of the world. • The map below show the concentrations of ozone over the northern hemisphere 1980-1991:-

11. Air Pressure: Luftdruck • Air pressure is the force exerted on you by the weight of tiny particles of air. • Air pressure at sea level is equivalent to a force of 1kg per cm² . Sea Level 1000 hPa Zugspitze 3000m 700 hPa Everest 8800m 350 hPa

12. Air pressure • This plastic bottle, sealed at approximately 2,000 m altitude, was crushed by the increase in atmospheric pressure when brought to sea level.

13. Air Pressure • We live at the bottom of an ocean -- an ocean of air. This air presses on everything, and we call that AIR PRESSURE. • Bernoulli discovered that air doesn't press as hard when it's moving. The faster it moves, the less it presses.

14. HelicoptersAir Resistance Bikes, cars and other vehicles experience air resistance as they move. Air resistance is caused by the frictional forces of the air against the vehicle. The faster the vehicle moves, the bigger the air resistance becomes. The top speed of a vehicle is reached when the force from the cyclist or engine is balanced by air resistance.

15. Natures helicopters

16. Air Resistance

17. Make our own helicopters • Use the pattern to copy the shape on to a piece of paper. • Cut it out. • Decorate • Fly