Greenhouse+Effect


 * Planetary Surface Temperatures & Greenhouse Effect**

Note: Consider using this additional resource -- @http://www.concord.org/activities/greenhouse-gases


 * Author: Benjamin Farr, 2011**

The purpose of this activity is for students to gain an understanding of what factors determine the surface temperature of a planet. They will be using a basic model for this, that takes into account the planet’s radius, orbital radius, albedo, and the strength of the greenhouse effect on the planet.
 * Purpose**

This activity is centered around the use of a computer model made using Mathematica, that models the surface temperature of planets, including a basic model for the greenhouse effect.
 * Overview**

Rubric

places. making careful observations and trying to make sense of those observations. single system in which the basic rules are everywhere the same and that the things and events in the universe occur in consistent patterns that are comprehensible through careful, systematic study. evidence from many sources in order to form a scientific account of the universe.
 * Student Outcomes**
 * AAAS 1A:**
 * P2:** Science investigations generally work the same way in different
 * E2:** Science is a process of trying to figure out how the world works by
 * H1:** Science is based on the assumption that the universe is a vast
 * AAAS 4A:**
 * H4:** Mathematical models and computer simulations are used in studying

from another. Whenever energy is lost from somewhere, it must have gone somewhere else. Sometimes when energy appears to be lost, it actually has been transferred to a system that is so large that the effect of the transferred energy is imperceptible.
 * AAAS 4E:**
 * P1:** The sun warms the land, air, and water.
 * M1:** Whenever energy appears in one place, it must have disappeared

system to its environment) in different ways: 1) thermally, when a warmer object is in contact with a cooler one; 2) mechanically, when two objects push or pull on each other over a distance; 3) electrically, when an electrical source such as a battery or generator is connected in a complete circuit to an electrical device; or 4) by electromagnetic waves. an object's temperature increases depends on how intense the light striking its surface is, how long the light shines on the object, and how much of the light is absorbed.
 * M2:** Energy can be transferred from one system to another (or from a
 * M6:** Light and other electromagnetic waves can warm objects. How much

10-15 minutes opening discussion 20-25 minutes working with computational model 5 minutes wrap-up discussion
 * Time**

11-12 Grade Astronomy
 * Level**

Mathematica Player Greenhouse model Mathematica player file - [|planetSurfaceTemperature.nbp] Greenhouse Model Activity Sheet
 * Materials and Tools**

Ensure the free Mathematica player program is downloaded and installed on classroom computers, and that the Greenhouse model player file is accessible.
 * Preparation**

Some previous discussion of energy and equilibrium would be helpful, but not necessary.
 * Prerequisites**

In this lesson, you will learn how the ideas of equilibrium and energy conservation can be used to develop a model for the surface temperature of planets. You will also use a basic model for the greenhouse effect, in order to develop an understanding of how the greenhouse effect can impact the surface temperature of a planet.
 * Background**

Students are first introduced to new topics in a 10-15 minute discussion at the beginning of class. The concept of equilibrium is revisited, now for the case of thermal equilibrium. The concept of flux is introduced to explain why a planet’s temperature depends on its distance from the Sun. Albedo is also introduced in order to determine how much incoming energy a planet will absorb. Black body radiation is reviewed to show how planets are able to radiate away energy. The class then has a short discussion about the greenhouse effect, and what effect that has on the surface temperature of a planet. Students are then shown a model for these processes, and a small discussion is had on what all of the parameters mean, and how they affect the planet’s temperature. Students then go through a worksheet using a computer program that uses the models discussed in class to determine the planetary temperatures. The class is ended with a short discussion of what values students found for the greenhouse parameters of Earth, Venus, Mercury, and the Moon, and how this affects their surface temperatures.
 * Teaching Notes**

Assessment is done by checking answers to the questions on the activity sheet. The final discussion is also meant to test students’ understanding of planetary surface temperatures and what affects them.
 * Assessment**