Describing Earth’s atmosphere How does Earth’s atmosphere affect life on earth? How do scientists describe and predict weather? What is climate and how does it impact life on earth?
Atmospheric composition 78% nitrogen and 21% oxygen 1% argon, hydrogen, carbon dioxide, water vapor, other gases Ozone layer: protection from sun’s harmful rays http://www.soest.hawaii.edu/GG/ASK/atmo-nitrogen.html
Structure of the atmosphere
To do Layers of the atmosphere Read Chapter 12.1 p. 409 – 414 Take notes
To do Background reading: Section 12.2 (p. 417 – 423) Answer the following questions (1 paragraph each): 1. What is the difference between radiation, convection and conduction? 2. Draw a diagram with labels to illustrate how the energy from the Sun is reflected or absorbed. 3. Describe the greenhouse effect in terms of radiation.
12.3 Air Currents
Global winds Wind = movement of air from areas of high pressure to low pressure Warm air (less pressure) and cold air (high pressure) Unequal heating of earth’s surface Near the equator: sunlight strikes at high angle, more sunlight per unit of surface area Near the north pole: sunlight strikes at low angle, less sunlight per unit of surface area
Global wind belt Trade winds: east to west, 30N and 30 S latitudes Westerlies: west to east, 30N and 60N, 30 S and 60S latitudes Polar easterlies: east to west near North and South pole
The Coriolis Effect Turn of the wind caused by earth's rotation
Sea and land breezes Sea breeze = wind that blows from the sea to the land due to local temperature and pressure differences Land breeze = wind that blows from land to the sea due to local temperature and pressure differences
12.4 Air Quality
http://www.bbc.com/news/world-asia-26319146 http://www.youtube.com/watch?v=aIRkax6WUwQ
Causes and effects of air pollution Photochemical smog = air pollution that forms from interaction between chemicals in the air and sunlight Acid precipitation = sulfur dioxide and nitrogen oxide combine with moisture in the atmosphere and forms pH lower than normal rain water
pH Test Materials Vinegar, coffee, distilled water, baking soda, household detergent, one liquid of your choice (tell me first) 2 Petri dishes 6 pH strips Procedure Drop two – three drops of the solution on pH paper. Determine the pH using the pH color chart. Record the pH of the different substances.
Acid Rain Research Research the following. Write down the sources that you use (at least 3). What is acid precipitatio? What is the pH of acid rain? Find out the causes and effects of acid rain. Create a table (such as below) to help you to organize your thoughts. How good/bad is pollution in Venezuela? Why? Causes Effects