Books for Students‎ > ‎Ozone‎ > ‎6. Loss and Surprise‎ > ‎

6-1 Ozone Monitoring

Ozone Monitoring

(Adapted from Monitoring Ozone from Your Classroom, National Air and Space Museum, Washington, D.C., 1990.)

The data on this page were taken by the Total Ozone Mapping Spectrometer (TOMS) on the Nimbus-7 satellite. The ozone concentration values refer to a column of the atmosphere above a particular region of Antarctica. The actual TOMS data, consisting of measurements for each day of the year, were averaged to obtain the more manageable number of three readings per month.

Graph the TOMS data.

Dobson Units (DU) are used to describe ozone concentrations. They were named after the scientist, G. M. B. Dobson, who invented one of the first instruments for measuring the concentration of ozone.

TOMS Data
Day Month Ozone (DU)
7 March 229
8   212
9   201
10 April 208
11   227
12   221
13 May 220
14   222
15   223
16 June 219
17   225
18   226
19 July 228
20   225
21   211
22 August 210
23   206
24   208
25 September 185
26   162
27   138
28 October 118
29   124
30   130
31 November 143
32   155
33   176
34 December 219
35   247
36   241

 


Graph Interpretation

  1. For which month was the ozone concentration value highest?

  2. For which month was the ozone concentration lowest?

  3. Remember that the seasons in the Southern Hemisphere are opposite those in the Northern Hemisphere. During which Antarctic seasons were ozone values highest and lowest?

  4. Do ozone levels seem related to the time of year? How?

  5. How could you verify if there is a seasonal variation of ozone levels over Antarctica?

  6. What could be a possible cause of the ozone fluctuations throughout the year?

  7. Are the measurements of the Nimbus-7 satellite consistent with what you would expect from the graph on page 49?


Comments