Lab 4: The Greenhouse Effect1. Light photons are an elementary particle that is a bundle of electr

Lab 4: The Greenhouse Effect

1. Light photons are an elementary particle that is a bundle of electromagnetic radiation within the visible light spectrum. It is the basic unit of that makes up all light. Infrared photons are the electromagnetic radiation having a longer wavelength than the visible spectrum

a. In the simulation, light photons are the yellow circles, infrared photons are the red circles.

b. The visible light from the sun hits the Earth’s surface. The surface absorbs the light and is heated. Infrared photons are then re-radiated off the surface. The infrared photons cannot pass through the atmosphere

2. When increasing the number of clouds on the simulator, visible light does not reach the surface of the Earth. Thus, there is not surface heating coming from those photons. Daytime and nighttime clouds have the opposite effects. Daytime clouds prevent the visible light from reaching the Earth’s surface so the temperature would be lower if there were no clouds. If clouds are present at night, the infrared photons that are re-emitted are trapped closer to the surface keeping the Earth’s surface warmer than if there were clouds.

3. By increasing the greenhouse gas concentrations, they serve the same effect as clouds. I did this by changing the “atmosphere during…” to adjustable concentration and increasing the “greenhouse gas concentration” to lots. When doing this, the infrared photons are unable to escape and are bounce back toward the Earth’s surface similar to the effect when clouds are present.

4. With no greenhouse gases and no clouds, the temperature hovers between -3°F and 0°F. Pushing the arrow all the way to the right for greenhouse gas concentration increases the temperature to a range between 70°F and 72°F. When the simulator is at no greenhouse gases and three clouds, the temperature hovers between 9°F and 17°F. When the simulator is at no clouds and the greenhouse gas concentration is at the maximum, the temperature hovers between 69°F and 75°F. Greenhouse gases are much more efficient at trapping infrared photons and thus heating the Earth.

5. When infrared photons are directed at methane, some photons are absorbed and re-emitted. When infrared photons are directed at carbon dioxide, some photons are absorbed and re-emitted. When

infrared photons are directed at nitrogen, infrared photons are not reemitted. When infrared photons are directed at water, some photons are absorbed and re-emitted. When infrared photons are directed at oxygen, some photons are not re-emitted. Based on this simulation, methane, carbon dioxide, and water are greenhouse gas molecules.

6. Clicking on the Glass Layers tab will provide a simulation of the interior of car being hotter than outside temperatures. Visible light will enter through the glass. It will hit the surfaces and re-emit infrared photons. The glass prevents all of the infrared photons from escaping back outside. The increased infrared photons in the car’s interior will increase the temperature.

7. An ice age is a period of colder global temperatures that features recurring glacial expansion across the Earth’s surface. Capable of lasting hundreds of millions of years, these periods are interspersed with regular warmer interglacial intervals in which at least one major ice sheet is present. Earth is currently in the midst of an ice age, as the Antarctic and Greenland ice sheets remain intact despite moderate temperatures.[1] The Pleistocene Epoch is typically defined as the time period that began about 2.6 million years ago and lasted until about 11,700 years ago. The most recent Ice Age occurred then, as glaciers covered huge parts of the planet Earth.[2] In the simulator, clicking on “ice age” drops the amount of greenhouse gases in the atmosphere. The infrared photons readily escape and are not bounced back down to warm the Earth. The temperature in the simulator hovers slightly above and below the freezing temperature of water.