Atmospheric Basics pages 282-288

Vocabulary:

1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
5. Exosphere
6. Radiation
7. Conduction
8. Convection

Objectives:

1. What is the gas and particle composition of the atmosphere?
2. List the 5 layers of the atmosphere in order and describe their properties
3. Describe the three types of energy transfer; conduction, convection, and radiation and relate them to heat transfer in the atmosphere

 Atmospheric Composition  page 282-283

The atmosphere extends from Earth’s surface into the far reaches of space. The ancient Greeks thought that the “air” of the atmosphere was one of four fundamental elements.

Air is actually a mixture of gases and not an element at all. How does a mixture differ from an element or compound?

Earth’s atmosphere consists of permanent and variable gases. About 99 % of Earth’s air is permanent atmospheric gases.

This is a graphic showing the representative ratios of Earth’s permanent gases.

Water vapor and ozone vary significantly from place to place. Think of the affect humidity has on the temperature in Nebraska in the summer vs the winter.

Carbon dioxide and water vapor are greenhouse gases and have a significant effect on Earth’s temperature.

1.  Water vapor varies as much as 4 % from place to place and season to season.
2. Carbon dioxide is another variable gas. 150 years ago, the carbon dioxide concentration was 280 ppm. Today, it is 380 pp. The increase id sue primarily due to burning fossil fuels such as coal, oil, and natural gas.

Carbon dioxide concentrations also vary through cycling in the carbon cycle.

Ozone

Molecules of ozone are formed by the addition of an oxygen atom to a molecule of oxygen. Ozone concentration varies seasonally at higher latitudes reaching a minimum in the spring.

The Ozone Layer has the greatest concentration of ozone. Use the graph to determine the range in altitude of the ozone layer.

What is the maximum concentration of ozone in the Ozone Layer?

Graph of Ozone concentration vs Height Above Earth’s Surface.

Use this link if you can’t see the graph.  http://ozonewatch.gsfc.nasa.gov/facts/ozone.html

Atmospheric Layers page 284-286

The atmosphere consists of 5 layers each differing in composition and temperature profile.

http://connected.mcgraw-hill.com/c2j/resourceLibrary.do?bookId=KOSMFW99ZJ2NCX8MZLX1S3Y51O&libraryId=6O7L784RGT1DBJ732L3JNHLVR8

  List the 5 layers from the layer closest to Earth to the layer furthest from Earth.

1. Troposphere contains most of the mass of the atmosphere.  Weather occurs here.  The temperature decreases with altitude.
2. Stratosphere The ozone layer is located here.  In the lower stratosphere, the temperature stays constant with altitude but from the ozone layer up, temperature increases with altitude until the stratopause.  The stratophere is heated by the ozone molecules which absorb UV light from the Sun.
3. Mesosphere Temperature decreases with altitude because very little solar radiation is absorbed in this layer.
4. Thermosphere The extremely low density of air causes the temperature to rise.  Temperatures can increase to 2000 degrees C.  The ionosphere which is made of electrically charged particles is part of the thermosphere.
5. Exosphere The outer most layer of the atmosphere extends from 600 km to 10, 000 km.  There is no clear boundary between the top of the exosphere and space.  The density of atoms and molecules in this layer is very low and they rarely collide.  Some move fast enough to escape Earth’s gravity into space.

Energy Transfer in the Atmosphere 286-288

Chapter 11.2 Properties of the Atmosphere