1 / 22

Section 11.1 – Atmosphere Basics

Section 11.1 – Atmosphere Basics. 8 th Grade Earth and Space Science Class Notes. Atmosphere Basics. Combination of gases, dust, water droplets, and ice crystals Surrounds the Earth Extends from the Earth’s surface to outer space. Picture of the Earth’s a tmosphere taken

luann
Download Presentation

Section 11.1 – Atmosphere Basics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Section 11.1 – Atmosphere Basics 8th Grade Earth and Space Science Class Notes

  2. Atmosphere Basics • Combination of gases, dust, water droplets, and ice crystals • Surrounds the Earth • Extends from the Earth’s surface to outer space Picture of the Earth’s atmosphere taken from a space shuttle

  3. Permanent Atmospheric Gases • Earth’s atmosphere consists mainly of nitrogen (78 percent) and oxygen (21 percent). • The amounts of nitrogen and oxygen in the atmosphere are fairly constant over recent time.

  4. Variable Atmospheric Gases • The concentrations of some atmospheric gases are not as constant over time. • The amount of water vapor, ozone, and carbon dioxide vary significantly from place to place.

  5. Water Vapor (H2O(g)) • Invisible, gaseous form of water • Can range of 0% - 4% • Concentration depends on the seasons, altitude, and properties of the surface underneath

  6. Carbon Dioxide (CO2) • During the past 150 years, the concentration of atmospheric carbon dioxide has increased, due primarily to the burning of fossil fuels. • Currently 0.039% (up by 0.028%)

  7. Ozone (O3) • Mostly in ozone layer (20 – 50 km above) • Only 0.0012% but plays important role in blocking out harmful rays from the sun • Concentration has decreased due to CFCs which are now banned • Scientists estimate it should fully recover by the 2100

  8. Atmosphere Particles • Contains variable amounts of solids in the form of tiny particles, such as dust, salt, and ice • Fungi and bacteria are often attached to these particles Fluorescent sample of bacteria taken from the air.

  9. Atmospheric Layers

  10. Troposphere • Closest to the Earth’s surface • Contains most of the atmosphere’s mass • Weather occurs in this layer • Air temperature decreases with altitude • Top is called tropopause

  11. Stratosphere • Above tropopause • Contains the ozone layer • Air temperature increases with altitude since the ozone layer absorbs the sun’s energy • Ends at the stratopause

  12. Mesosphere • Above the stratopause • Air temperature decreases with altitude since very little solar radiation is absorbed • Ends at mesopause

  13. Thermosphere • Low air density so temperature rises (can be over 1000°C) • Contains the ionosphere (made up of charged particles) • Ends at thermopause

  14. Exosphere • Outermost layer • Transitional region between the Earth’s atmosphere and outer space

  15. Review of Thermal Energy and Heat • Remember – all matter is made of particles in constant, random motion! • These moving particles contain kinetic energy. • The total kinetic energy of the moving particles is called thermal energy. Less thermal energy  More thermal  energy

  16. Review of Thermal Energy and Heat • Heat is the transfer of thermal energy from regions of higher temperature to regions of lower temperature Direction of movement 

  17. Energy Transfer in the Atmosphere • In the atmosphere thermal energy is transferred by: • Radiation • Conduction • Convection

  18. Radiation • Transfer of thermal energy by electromagnetic waves • Thermal energy is transferred from the Sun to Earth by radiation

  19. Absorption and Reflection • Incoming solar radiation is either reflected back into space or absorbed by Earth’s atmosphere or its surface. • 30% reflected • 20% absorbed by atmosphere and clouds • 50% absorbed by Earth’s surface

  20. Rate of Absorption • Depends on physical characteristics of the surface and the amount of solar radiation • Examples – water heats and cools more slowly; dark colors absorb energy faster Solar Radiation Around the World Darker = more

  21. Conduction • Transfer of thermal energy when objects at two different temperatures are in contact • Occurs between the Earth’s surface and lowest part of the atmosphere

  22. Convection • Remember – convection is the transfer of thermal energy by the movement of heated material from one place to another • Near the Earth’s surface air becomes heated, expands, and rises then as it rises it cools, contracts, and sinks. • This creates convection currents in the atmosphere.

More Related