1. Interactions of Solar Energy with Land and Air Weather Dynamics Science 10

2. Heating Dry Land If you take 1 gram and sand and 1 gram of water and heat them up, the sand will warm up 5 times as fast as the water. Shocked? I think so! You have already learned that water’s high specific heat capacity has a large role to play in this discrepancy. Water takes much more energy to heat up and therefore the sand is able to get warmer, quicker

3. Heating Dry Land A second reason for drastic change in temperatures is that unlike water, all the radiant light that hits the sand is absorbed over only the top few centimetres. Since light cannot penetrate through the sand, the only way for sand which does not receive light to warm up is through conduction (touching other sand granuoles that were lit). Water’s translucency allows light to penetrate further and spread out over a wider area, making it “cooler”.

4. Heating the Air All 3 ways that heat transfers in an environment are used to heat the air. Can you think of how each one plays a part? Conduction: Energetic molecules of land collide with cooler air molecules close to the surface, giving the molecules in the air some energy. This heats the air. Convection: These warmed air molecules become less dense and rise, allowing cooler air molecules to reach the surface and allow conduction to warm them as well. Radiation: The sun’s solar radiation warms the air molecules as well.

5. Layers of our Atmosphere Our atmosphere has Layers!!!

6. The 4 Atmospheric Layers Although there are no defining lines between parts, scientists have divided our atmosphere up into 4 layers. Each part is classified by its distance from the Earth’s surface, as well as common temperature trends in each of the regions. Drastic changes in temperature (either increasing or decreasing) warranty a new layer with a new name!

7. Layer 1: Troposphere Located about 10km from the Earth’s surface. All weather that occurs, occurs in the troposphere. Unlike Earth, who’s temperature flucates on a daily basis, the temperature in the troposphere remains fairly constant at -57°C.

8. Layer 2: Stratosphere From the troposphere to about 50km from the Earth’s surface. This zone is classified as a different zone because the temperature actually increases here (Out in space the temperature goes up? Huh?). The reason for the sudden temperature increase is the presence of ozone. (Your ozone layer is found here!)

9. Ozone The ozone layer seperates the troposphere and the stratosphere. Ozone absorbs ultraviolet light from the Sun This causes the temperature to rise in the stratosphere. If the ozone layer was not present, the amount of ultraviolet radiation that reached the Earth’s surface would be hazardous to all living creatures. And so, the ozone layer makes life on Earth possible

10. Reviewski – Answer On your Own Give me 1 example of conduction, convection, and radiation. What is specific heat capacity? Heat of vaporization? Heat of fusion? What is humidity? Why does land heat up quicker than water? What is the first layer of the atmosphere? What happens here? What is the second layer of the atmosphere? What happens here?

11. Layer 3: Mesosphere Between 50 and 60 km above sea level, the temperature levels off again (like in the troposphere) at about -2°C. This area marks the top of the stratosphere. The next layer, the mesosphere extends from around 60km from the Earth’s surface to about 90 to 100 km.

12. Layer 3: Mesosphere The mesosphere is defined by another sudden drop in temperature. Here the temperature levels off to a frigid - 90°C to -100°C. BrrrRRRrrr! Meteors from outer space often penetrate up to this layer of the atmosphere, but then burn up due to air friction.

13. Layer 4: Thermosphere At an altitude of 100km, the temperature begins to rise and becomes much, much higher than any other level. Since this region has such a high temperature, scientists called it the thermosphere.

14. Layer 4: Thermosphere Meteorologists discovered that oxygen molecules in this layer absorb the very high energy ultraviolet light, accounting for the drastic increase in temperature. At 150km, the temperature reaches 180°C. At 500km, the temperature hits a sweltering 600°C!

15. The Ionosphere In between the mesosphere and the thermosphere is a layer of charged particles called the ionosphere. As already mentioned, the thermosphere warms due to atoms absorbing ultraviolet light. The absorption of this high energy ultraviolet light cause electrons to be ejected from atoms, creating ions.

16. The Ionosphere The charged ions have a direct effect on radio and satellite communications. The ionosphere bends radio waves, making it possible to pick up signals at great distances from a radio transmitter. This bending of waves also makes it impossible to use radio waves to communicate with satellites, since they waves cannot pass the ionosphere to reach the satellites. We use microwaves (which are small enough to pass through the ionosphere to communicate with satellites).

17. So what is the order of the layers of the atmosphere? Can you get them all? 1.Troposphere Ozone Stratosphere Mesosphere Ionosphere Thermosphere

18. Assignment Draw a diagram of a section of the Earth. In this show each of the layers of the earth’s atmosphere (include the ozone and the ionosphere). For each give: the distance from the Earth’s surface the temperature (if not exact, give the range that the temperature’s may go to). draw a picture of what happens there (for example weather in the troposphere). Fully colour and label your diagram.

19. Thermosphere The thermosphere is also the location of the magnificent display of northern and southern lights called the aurora. This array of lights is created by clusters of charged particles with extremely high energy from the Sun. These particles (sometimes called solar wind), collide with gases passing on energy and exciting these gases. The excess energy from the collisions is shown in the lights we see in the sky. The reason this only occurs at the North and South poles is due to the Earth’s magnetic field pulling in gases at the poles, and no where else. These gases which get excited only enter the atmosphere at the poles where the magnetic fields pull inward

21. Earth’s Magnetic Field The magnetic field around Earth exists because of electrical currents in the Earth’s molten metallic core are rotating. The magnetic field shields the Earth from solar winds of the sun. Solar wind are highly energetic charged particles from the Sun which would be potentially harmful to life on Earth if they were able to enter the atmosphere (Thank You Mr. Magnetic Field!)

22. Greenhouse Gases As you already learned, oxygen in the thermosphere absorbs a lot of ultraviolet light. What do the other gases in our atmosphere do? What is the “Greenhouse Effect?” Greenhouse gases – carbon dioxide, methane, dinitrogen oxide, and CFCs.

23. Greenhouse Gases There is very little absorption of any other solar radiation by gases (Remember what solar radiation included). But! The atmosphere (specifically Carbon Dioxide and Water Vapour) absorb the longer wavelength re-radiation (radiation that was previously absorbed and released). Huh? What does this mean? Good question.

24. Greenhouse Gases The other greenhouse gases (like carbon dioxide) trap the infrared radiation released from Earth and warms the atmosphere before it escapes into space. If there were no greenhouse gases at all, Earth’s average temperature would be 35°C lower. Since plants could not grow in these conditions, greenhouse gases are necessary for life on Earth. So these gases are good! Why then are scientists concerned about the “Greenhouse Effect”?

25. Greenhouse Gases The concentration of carbon dioxide in the atmosphere is critical. Too little – Earth would be too cold. Too much – Earth’s temperatures would rise to a potentially dangerous extent. How do you think an increase in temperatures might affect life on Earth? How would it affect the weather?

26. What Should I Know? Why land heats slower than water. How air heats up using all 3 types of transfer. The 4 layers of the atmosphere. How the aurora is formed. What is the magnetic field used for. How greenhouse gases affect Earth Why the Greenhouse Gas effect is bad.

27. Do You Understand? Why does land heat up faster than water? Does all of the land heat up? Explain. Explain the role of conduction in the heating of air. Why is it necessary to use microwaves to send signals to and from communication satellites? What causes the aurora? What do greenhouse gases do? Are they bad?