PhET/C2/The-Greenhouse-Effect/English-timed

Time	Narration
00:01	Welcome to this tutorial on Greenhouse Effect, an Interactive PhET simulation.
00:07	In this tutorial, we will Demonstrate Greenhouse Effect, using Interactive PhET simulation.
00:14	To follow this tutorial you should have knowledge of High School Science.
00:20	Here I am using- Ubuntu Linux OS version 14.04
00:26	Java version 1.7.0
00:30	Firefox Web Browser version 53.02.2.
00:36	Using this simulation students will learn, 1. Effect of greenhouse gases on atmospheric temperature.
00:44	2. Explore and compare the atmosphere of Ice age and Today.
00:49	3. Effect of Glass panes and Clouds on atmospheric temperature.
00:55	4. Interaction of photons with atmospheric gases.
00:59	5. Contribution of atmospheric gases to Greenhouse Effect.
01:04	Greenhouse Effect It is a phenomenon in which, earth's atmosphere traps radiation emitted by sun.
01:13	This effect is caused by gases in the atmosphere.
01:17	They retain the heat radiated back from earth's surface.
01:22	This slide shows greenhouse gases and their percentages.
01:27	This process is similar to what happens inside a Greenhouse.
01:32	In cold places, fruits and vegetables are grown in glass covered area called a Greenhouse.
01:40	In a Greenhouse, solar radiations pass through the transparent glass and heat up the soil.
01:47	Some of this heat is absorbed by the glass and some is reflected.
01:52	This mechanism keeps the energy of the sun trapped in the Greenhouse.
01:58	Use the following link to download the simulation.
02:02	I have already downloaded the Greenhouse Effect simulation to my Downloads folder.
02:08	I will open the simulation using the terminal.
02:12	Open the terminal.
02:14	At the prompt type cd Downloads and press enter.
02:20	Then type, java space hyphen jar space greenhouse_en.jar and press enter.
02:31	Greenhouse Effect simulation opens.
02:35	The simulation has 3 screens, Greenhouse Effect Glass Layers and Photon Absorption.
02:45	Greenhouse Effect screen shows Earth's atmosphere.
02:49	Light from Sun is depicted as yellow photons.
02:54	The radiated heat from Earth's surface is shown as red infrared photons.
03:00	On the right-hand side panel, we have options to explore the atmosphere.
03:06	By default Atmosphere during is set as Today.
03:11	Observe the composition of greenhouse gases for Today's Atmosphere.
03:16	There is a thermometer to record the temperature in Kelvin and Fahrenheit scales.
03:23	Options panel has radio buttons to display temperature in, Fahrenheit or Celsius units.
03:31	At the bottom of the screen there are buttons to Pause and Play simulation.
03:37	Drag the slider to change the speed of the animation from fast to slow.
03:44	Observe the temperature on the thermometer.
03:48	Click on Adjustable concentration button.
03:52	It will increase the concentration of greenhouse gases.
03:57	Then drag the Greenhouse Gas Concentration slider towards Lots .
04:03	Observe the temperature on the thermometer.
04:07	As the concentration of greenhouse gases increases, temperature increases.
04:13	Does clouds in atmosphere help in reducing the Greenhouse Effect?
04:18	Add Clouds to the simulation from the Options menu.
04:23	Observe the temperature. Note that, Clouds will help the atmosphere, to retain heat.
04:30	You can also compare the atmosphere during 18th century and Ice age.
04:36	Click on 1750 radio button.
04:40	Note the composition of greenhouse gases.
04:44	Click on Ice age radio button.
04:47	Note the change in composition of greenhouse gases.
04:52	Percentage composition of greenhouse gases in Ice age is much lower.
04:58	Click on Reset All button at the bottom of the screen to reset the simulation.
05:04	Click on Yes to confirm your action.
05:08	Now let us explore other screens in this window.
05:13	Click on Glass Layers tab.
05:16	Here, we have an option to add Glass Panes to the simulation.
05:22	This helps to understand the effect of Glass Panes on atmospheric temperature.
05:28	Let us add a Glass Pane and observe the change in temperature.
05:33	Add more Glass Panes and see what happens.
05:38	Click on Photon Absorption tab.
05:41	Drag the Infrared Photon slider to release the photons.
05:46	Click on Atmospheric Gases radio buttons, one by one and check the vibrations.
06:00	Click on Build Atmosphere radio button.
06:04	Drag the sliders for the respective atoms.
06:19	Then drag the slider for releasing Infrared or Visible Photons.
06:25	Observe the vibrations of the molecules.
06:29	Let us summarize.
06:31	In this tutorial we have learnt, About the effect of greenhouse gases on atmospheric temperature.
06:38	Compared the atmosphere of Ice age and Today.
06:43	Effect of Glass panes and Clouds on atmospheric temperature.
06:48	Interaction of photons with atmospheric gases.
06:52	Contribution of atmospheric gases to Greenhouse Effect.
06:57	As an assignment, Compare atmospheric temperature during 18th century and Ice age.
07:05	Add Clouds to the simulation and observe the changes in the temperature.
07:11	Explore Glass layers and Photon Absorption screens.
07:16	Explain why Glass panes increase the temperature of the atmosphere.
07:22	The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.
07:31	The Spoken Tutorial Project team: conducts workshops using spoken tutorials and gives certificates on passing online tests.
07:41	For more details, please write to us.
07:45	Please post your timed queries on this forum.
07:49	This project is partially funded by Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.
07:57	Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India. More information on this mission is available at this link.
08:09	This tutorial is contributed by Snehalatha Kaliappan and Meenal Ghoderao from IIT-Bombay. Thank you for joining

Contributors and Content Editors

PoojaMoolya, Sandhya.np14, Snehalathak