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Lessons and Modules

Introduction to Clouds

Accessing NASA Satellite Imaging Data

In the previous section, illustrations of satellite images explain the process of converting observations into a digital format. This section allows you to use a data analysis utility to access and read digitized data. The demonstration program will give you a chance to identify the types of clouds that appear in the data while getting accustomed to the interface. The steps listed below will lead you through this activity.

Sampling the Data

View properties of a snapshot of a midlatitude storm

  1. You should see two images below that display the cloud optical thickness and the cloud top pressure data for a storm that occured on April 2, 1988. Click on a point on the optical thickness image that indicates clouds with the greatest optical thickness.
  1. Notice the corresponding point also being highlighted in the cloud top pressure image on the right. The values of your selected data point should appear in the windows on the right side of each image. Select two more points of high optical thickness.
  2. You should now see a set of three data values (for each point you selected) in the columns to the right of each of the images. The next step is to determine what kind of optically thick clouds you have selected.
  3. To identify storm clouds in satellite data images, numerical data for cloud optical thickness and cloud top pressure should be inspected and compared with the cloud type classification table. Determine the cloud types for each of your three data points, and select your results in the table below:

Discuss your choices with your instructor. Then continue with data analysis and graphing by analyzing cloud types in a midlatitude storm.