The atmosphere is a mixture of gases, such as nitrogen, oxygen, argon, carbon dioxide, trace gases and water vapor. The amount of each gas in the mixture is usually very constant from the surface of the planet up to the top of the troposphere. These gases are constantly being used and renewed by the processes of respiration, photosynthesis, evaporation and condensation, the weathering of rock, and the decay of organic matter.
The atmosphere has different properties at different elevations and different locations around the earth. The air pressure is less on the top of mountains (higher elevation) than in valleys. At the equator the atmosphere is warmer; at the poles it is cooler. The uneven heating of land and water causes a rising and sinking of warm and cool air masses, creating convection currents and causing winds.
Five layers make up the atmosphere: the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Each of these layers has unique properties. Weather occurs in the troposphere and is the physical condition of the atmosphere at a specific place at a specific time. Fronts, global wind systems, atmospheric pressure changes and many other factors influence the weather. Major atmospheric activities such as thunderstorms, tornadoes and hurricanes affect humans and can result in huge natural disasters.
Technology has greatly influenced the ease and accuracy of predicting weather. Weather data at thousands of locations can be gathered instantaneously and applied to weather prediction models to produce weather maps. Weather maps show air masses, fronts, and pressure centers, helping to predict approaching weather. Weather forecasting has been improved by the additional data gained from Doppler radar units and satellites.
Air quality affects the quality of life for all organisms on Earth. Natural and human activities greatly influence the quality of the air. Technology has allowed us to measure the characteristics of the air and to monitor how air quality changes. This information helps us make informed decisions to protect air quality and the risks to organisms and human health.
The cumulative ecological effects of global ozone depletion, air pollution, increased particulate matter, acid rain, and global warming concern the entire global community. Studies have shown that human activity influenced and impacted the global ecosystem.
IX. Notes to the teacher/storyline
The first lesson begins with an introduction to the atmosphere, its composition and properties of each layer. Students will begin the lesson by investigating ultraviolet rays using UV beads. Throughout the lesson, they will learn about the three ways energy can be transferred and apply each to how it impacts weather. Finally, students will look at the layers of the atmosphere and create a scale model illustrating each layer.
The second lesson focuses on atmospheric conditions and weather hazards. It begins with an overview of clouds and several teacher demonstrations, which will lead into a discussion on stewardship and the effects of pollution. Students will complete several labs on predicting if air has mass and its behavior under certain conditions. The lesson will be concluded with a discussion of weather conditions and hazards. Students will collect daily readings of relative humidity and create a graph illustrating the data. As a culminating activity, several project choices and foldable options are included.
The third lesson focuses on using technology to study weather hazards. Students will be introduced to reading weather maps and review the types of symbols used on a map. Several resources are provided as a way for students to reinforce and apply what they learned. They will then create their own weather maps. A culminating internet scavenger hunt will conclude the lesson.
The fourth and final lesson focuses on air pollution. It begins with an overview of ultraviolet radiation and the affect it can have on a population. Students will discuss air quality and the affects humans can have on it. Using what they learned, students will create an airborne junk detector and collect data. They will then create a foldable to summarize their findings.
Additional resources, video topics, websites, extensions and a summative assessment are located at the end of the unit.
Ultraviolet beads (enough for each student to have several)
String for the beads
Different types of materials to test the beads for a class project
(sunglasses, sunscreen with various SPF’s, water, construction
paper, various materials, tissues, mirror, light bulbs, Ziploc, jar…)
A protractor, compass, jar lid, or circle template
One set of agree and disagree signs
Baby food jar with two large diameter straws
1000 ml beaker filled with ice water
Food coloring (blue and green work best)
VI. Notes to Teacher:
The following website can be used to order ultra violet beads. You may want to give students several on a string or just 1 or 2 to use for the investigation. They can do the lab at home or you can investigate as a class. Students can informally discuss their findings and/or write a lab report.