Temperature Exercise based on WorldWatcher Software

Introduction

Daniel Edelson presented the elements of this exercise to participants at the Second International Conference on Geoscience Education, July 31, 1997. With his permission, it is presented here for the MATHCOUNTS Coaches as an example of a mathematics-rich activity.

Creating a World Temperature Map - Testing what you Know

Select six crayons of different colors and assign a color to the following temperature ranges:
less than 10F
between 11F and 30F

between 31F and 50F

between 51F and 70F

between 71F and 90F

greater than 90F


Use your six colors and the map above to display what you think the average temperatures around the world would be for the month of July.

What you Want to Know

The WorldWatcher software allows you to display the actual average temperatures on a global map.(It also allows you to color your own computer-map) The figures below illustrate the kind of information that can be gotten from this program. The maps are for the months of January and July. Note that the cursor's position is identified by the printout that gives its coordinates, identification and mean temperature for the two months.

What have you learned

Dan suggests that you reflect on what you thought about while making your drawing

You might be interested in seeing a representation of the difference in temperture between the two months. The WorldWatcher software allows you to subtract the values of the first picture from those in the second and displays these differences as a map.

What more would you like to inviestigate about global temperature? For example, is there any correlation between annual average temperature and population?

The data are displayed using an equidistant rectangular projection. This means that a square degree is shown as the same size at the poles and equator, when its actual surface area is not the same. The result is that areas close to the poles appear to be larger than they are in relation to areas near the equator. Cartographers often use other projections to display regions of the earth in sizes that more faithfully represent their actual sizes. One of the most popular of these projections is the Mollweide projection which is suggestive of the spherical shape of the earth. WorldWatch gives you the option of this display; an example of this projection is given below and represesnts a different display of the same temperatue data in the previous diagram that compares temperature with population.

For a closer approximation to the representation of a spherical earth, this projection can be cut out and pasted together to make a 'globe".