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Learn about the different types of electromagnetic radiation, their energy levels, and their interactions with surfaces. Understand the greenhouse effect through experiments and explore the importance of greenhouse gases in Earth's temperature rise.
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Lab 5: Infrared Radiation and the Greenhouse Effect Key Objectives • Differentiate visible vs. infrared radiation • Expose how the type and amount of electromagnetic light emitted from an object depends on its temperature • Understand different types of radiative transfer processes • Understanding Earth’s greenhouse effect through experiment
Electromagnetic Radiation All types of electromagnetic radiation travel at the speed of light (c=3*108 m/s) However, different types have different wavelengths (λ), and hence frequencies (ν, “nu”) Wave equation: ν = c/λ
Which wavelengths have more energy? Increasing Energy
If an object is heated enough, it will first glow red. With much more heating, it will then glow white. Radiation Intensity Blue Green Red Visible Light Infrared Light Wavelength
Solar vs. Terrestrial Radiation Solar Radiation: More Total Radiation, Short λ (Visible Peak) Earth Radiation: Less Total Radiation, Long λ (IR Peak)
Visible vs. IR Radiation Reflected Visible Radiation Emitted Infrared Radiation The amount of emitted infrared radiation primarily depends on the object’s temperature
3PM MST 1/11/17 Infrared Satellite Image Clouds are very effective at blocking surface IR from reaching space!!! Visible Satellite Image
Phet Greenhouse Gas Simulation http://phet.colorado.edu/en/simulation/greenhouse
Which GHGs are most important? + 33 ºC Greenhouse effect for Earth Broken down: + 32.5 ºC from H20 Vapor + 0.5ºC from CO2 Ozone
Experiment 1 Room Temp. Sheet Room Temp. Sheet Use IR thermometer to measure room temperature pot + 0-8 sheets atop it Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet
Experiment 2 Room Temp. Sheet Room Temp. Sheet Use IR thermometer to measure high temperature pot + 0-8 sheets atop it Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet
Experiment 3 Use IR thermometer to measure high temperature pot + thin liquid layer atop it Also measure thin liquid layer itself using dial thermometer
Experiment 4 Room Temp. Sheet Use IR thermometer to measure clear (or least cloudy) sky + 1, 2, 4, & 8 sheets between you & that sky DO NOT AIM IR THERMOMETER AT SUN!! Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Room Temp. Sheet Warm ground