Part 2—Display Data in the Graphing Tool

In any step, click the Show me link to reveal extra information. If you prefer a printout of the full set of instructions for this part, choose Print from the File menu.

Step 1-
Display the Default Graph: Maximum Air Temperature

Be sure Reynolds High School is still checked (see Part 1). The default graph will be maximum temperature unless you select a different column for which the school has data. Let us look at maximum temperature measurements for Reynolds school. Above the list of schools, choose Make a Graph in the green box and click on Go.

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Above the list of schols, choose Make a Graph in the green box and click on Go.

Link on the GLOBE Web site that creates a graph or other data requests.

When you click Make a Graph, GO , you open the GLOBE Graphing Tool. The default graph always shows the Maximum Air Temperature data for the entire period of time that a school has been participating in the GLOBE program, but as you'll see later, there are many options for customizing your view of any data that the school has collected. In this case you are looking at the daily maximum temperature reading at Reynolds Jr Sr High School across an eight year time period.

Graph: 1996 through 2003; maximum air temperature; Greenville, PA

The Maximum Air Temperature is showing somewhat of a repeating pattern here. What do you think the reason for this is?
Is the pattern similar to one you might expect to see for maximum air temperature in your own city or town? If not, what are the differences?

Step 2-
Change the Time Frame of the Graph to Two Years

Below the graph, there is a box labeled, "Graph Data and Display Section". In the left side of that box, change the upper YYYY date from 1995 to 1998. Change the MM date from 10 to 01. Leave the DD date at 01. This will change the starting date of the graph to January 1, 1998. In the lower date box, change the ending date of the graph to December 31, 1999.

Below the section of the screen where you can change the time frame of the data displayed in the graph, change the size of the graph from small to large. At the bottom of the box, click the Redraw button.

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Below the graph, there is a box labeled, "Graph Data and Display Section"

In the left side of that box, change the upper YYYY date from 1995 to 1998. Change the MM date from 10 to 01. Leave the DD date at 01. This will change the starting date of the graph to January 1, 1998.
In the lower date box, change the ending date of the graph to December 31, 1999.
Below the section of the screen where you can change the time frame of the data displayed in the graph, change the size of the graph from small to large.
At the bottom of the box, click the Redraw button.

GLOBE tool for selecting parameters to display in a graph

You now have just two years of maximum temperatures on the screen—all of 1998 and 1999—and you may see that each day is represented by a small red triangle.

Graph: 1998 and 1999; maximum air temperature; Greenville

Look at the temperature scale, which runs along each edge of the graph. On approximately what date does the highest maximum daily temperature occur in 1998? When does it occur in 1999?

Compare the two years and describe the differences and similarities you see.

Step 3-
Add Data for Soil Moisture (10 cm) to the Graph

In the CURRENTLY SELECTED DATASETS menu, be sure that Maximum Temperature is still highlighted. Then, holding down the Command-Shift keys (Mac) or Control key (PC), scroll down to Soil Moisture (10 cm) and highlight it. Click Redraw.

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In the list of databases below the graph, be sure that Maximum Temperature is still highlighted. Then, holding down the Command-Shift keys (Mac) or Control key (PC), scroll down to Soil Moisture (10 cm) and highlight it. Click Redraw.

You should now have two data sets that appear in the graph. Soil moisture content is defined in terms of weight. It is a measure of the weight of water that exists in a gram of soil. Notice that the scale along the right side of the graph has changed. The unit of measurement for soil moisture is gram/gram, or g/g.

With your cursor over the graph itself, use Control -> Click (Mac) or Right Click (PC) to open a menu and save the image to the disk. Rename the image and save it in a new folder. Now re-open the image and print it.

Graph: 1998 and 1999; maximum air temperature, soil moisture; Greenville

During which months does soil moisture at 10 cm remain basically steady?

During which months does soil moisture at 10 cm change quite frequently?

What change do you notice as you compare soil moisture for 1998 with 1999?

Step 4-
Add Data for Soil Moisture (90 cm) to the Graph

Holding down the Command-Shift keys (Mac) or Control key (PC), and making sure that Maximum Temperature and Soil Moisture (10 cm) are still highlighted, highlight Soil Moisture (90 cm). Change the Data (Y) Axis Range to Use a fixed range, and click Redraw.

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Hold down the Command-Shift keys (Mac) or Control key (PC) and highlight Soil Moisture (90 cm).
Change the Data (Y) Axis Range to Use a fixed range
Click Redraw.
As described above, download, rename, and save the image. Now re-open the image and print it.

In what ways is the graph of Soil Moisture (90 cm) similar to the graph of Soil Moisture (10 cm)?
In what ways are the two Soil Moisture graphs different?
How does the 1998 graph compare with the 1999 graph for soil moisture at each depth?

Step 5-
Add Data for Rainfall to the Graph

Holding down the Command-Shift keys (Mac) or Control key (PC) and making sure that all three sets of data are still highlighted at the top of the list, scroll down to Rainfall and highlight it. Make sure the option for the Data Axis Range is Use a fixed range, and click Redraw.

Download, rename, and save the image. Now re-open the image and print it. You may want to use colored pencils to highlight the different data sets.

Graph: 1998 and 1999; maximum air temperature, soil moisture, precipitation; Greenville

Notice that a new scale has been added to the right of the graph, and that the unit of measurement is mm for millimeters of rain.There is now a lot of data crowded into a small space. In Part 3 you will be getting a closer look at the details. However, you should be able to see enough detail to answer this one last question about the data.