Download and Analysis of Mars-Based Temperature Data

How Does Near-Surface Temperature Change with Height on Mars?
Claris Works 4.0 (Macintosh) Version

Purpose: to "download" and import data into Claris Works 4.0 so you may analyze it for patterns and significance using the Make Chart option.

Procedure: Print this worksheet to follow along and work with a partner (if possible). Similar procedures are available for those using Microsoft Excel 4.0 or Microsoft Excel 5.0.

1. Begin at the home page of our site (Live from Earth and Mars, http://www-k12.atmos.washington.edu/k12/).

2. Click the "Pathfinder" graphic to get to the Mars Pathfinder mission and data.

3. Click "Mars Meteorological Data and Graphs: Latest Pathfinder and Viking."

4. Scroll down to "Data Tables" and click the link "Subset of Pathfinder Temperatures, Sols 2­7." Wait for the data to be transferred and loaded into a table.

5. Peruse the data for understanding and patterns. What do you notice about temperatures over a day and at different heights?

6. Click the "Back" button to return to the previous page.

7. Click on the link "Data Interchange Format" below the "Subset..." link. (Note: you can click HERE to download the pre-formatted data in one step)

8. Accept the download by clicking "Save" in the "Download Dialog Box."

9. Save the file by clicking "Desktop" then clicking "Save" in the "Save Dialog Box." You should now have saved the file "temps.bin"

10. Launch ClarisWorks. In the "New Document Dialog Box" click "Cancel."

11. Load the data file by pulling down "File" to "Open..." In the dialogue box, click "Desktop," click the icon for your computer's hard drive, and click "Open." Click the saved file (temps.bin) and click "Open." ClarisWorks will import the pre-formatted spreadsheet file.

12. Save the file as a ClarisWorks document by pulling down "File" to "Save As..." giving the file a descriptive name (such as "Mars Temperatures, Sols 2-7), and clicking "Save."

Now we're ready for some data analysis. Scroll the data columns to get a feel for the range of values. Do you notice any patterns?

13. Create empty columns to the left of each of the last two temperature columns. Highlight the second temperature column (E) throughout the data range (cells 3 ­ 238). Pull down the "Calculate" menu to "Insert Cells," click "Shift Cells Right," and click "OK." If you get a warning about not having sufficient memory to recalculate, click "OK." Repeat the procedure for column G (cells 3 ­ 238). You now have empty columns before each of the last two temperature data columns.

14. Create X-value columns for each of the last two temperature columns. Copy the Decimal Sol column (C) by highlighting the data cells range (cells 3 ­ 238) and pulling down the "Edit" menu to "Copy." Click in the first cell where the data is to be pasted (cell E3) and paste the "Decimal Sol" data by pulling down the "Edit" menu to "Paste." Repeat pasting "Decimal Sol" for the other empty column (cell G3). The spreadsheet should now have "Decimal Sol" data before each temperature data column.

15. Save your changes by pulling down under "File" to "Save."

16. Highlight the data you wish to graph (such as C4 to H238) by dragging from the first cell to the last one.

17. Begin the graphing utility by pulling down "Options" to "Make Chart."

18. Click "X-Y Scatter." Click the "Axes" button and input a descriptive term for each (such as "Temperatures, °C for "Y" and "Martian Sol" for "X"). Click "Series" and pull down "Edit Series" to select each series, change the "Point Size" to 2, and give each series a unique symbol rather than "X" for each symbol). Click "OK."

19. Enlarge your graph by dragging one of the "handles" in the corner of the graph. Examine the graph more closely by clicking on the "zoom" icon in the lower-left corner of the window.

20. Find the Martian diurnal (daily) cycle of temperature by looking at one of the temperature columns plotted against decimal sol. (No fair just looking at sol number!) How would you describe a Martian diurnal cycle to another person?

The steepness of the temperature curve provides information about the rate at which the Martian atmosphere heats and cools. The steeper the curve the more quickly the temperature changes. Examine the shape of the temperature curves you plotted. Calculate the heating rate and the cooling rates for the Martian atmosphere. Does Mars cool at the same rate as it heats?

21. Compare the diurnal cycle of temperature of these 6 sols with one another. Is there a sol-to-sol variation? Describe any variations you see. What are some possible causes of these variations?

22. Compare the temperatures recorded for the 3 different sensor heights. What patterns do you see over a day? What patterns do you see during the night? Hypothesize about possible causes of these variations. Write your hypothesis and explain it to another person.

23. Print the graphs you believe are particularly representative of what you learned. Make some notes on the graphs that address the above questions.

24. Save the file (with associated graph) by pulling down from "File" to "Save."

Extensions: Try using the Analysis Tools under the Options pull-down menu to analyze these data further. You can calculate daily average temperatures and standard variations, correlations between temperatures at different heights, or with time. You can analyze the variance in the temperature measurements, or compute any number of interesting statistics. Forge on according to your own interests and capabilities!

 

© 1998 Live from Earth and Mars, Janice DeCosmo, and Rich Edgerton