Global Sea Surface Temperatures:

Directions: Go to the sea surface temperature image page.  Your teacher has the web site address.
A) Save every global sea surface temperature image as either a TIFF or a PICT.
B) Use image processing software to create an animated movie.
C) Answer the questions below.  To answer some of the questions, you will need to use the following formulas:
Temperature conversion from DN Value to degrees Celsius: C = (255 - DN) * .15 - 2.1
Temperature conversion from degrees Celsius to degrees Fahrenheit: F = 1.8 * C + 32


1)  What color represents the warmest ocean tempertures?  What color represent the coldest ocean tempertures?
 
 

2) In what ocean do the annual sea surface temperatures seem to vary the most?  In what part (North, Central, South) of that ocean?
 
 

Load the 1982 image only.  In NIH or Scion Image, choose the Analyze option from the menu bar, then select Measure.
3) What does the "Minimum Value" represent?
 
 

4) What is the Surface Water Temperature (In degrees Celsius) of the "Minimum Value"?
 
 

5) The "Mean" is the average of all the pixel values in the image.  Does the value for the "Mean" represent the DN Value for the average Surface Water Temperature in that image?  Why or why not?
 
 
 

From the "Tools" menu box, select the Box tool.  (It should be the first icon in the second column.) Place the cursor in the image so that the X value equals 0, the Y value equals 90 (NOTE: the Y value represents the equator).  Draw a rectangle that is 90 pixels long and 45 pixels wide.  Now select Measure from the Analyze option of the menu bar.  Your box will be the correct size if the area of the box is 4050 square pixels.

6) What are the Mean, the Minimum Value, and the Maximum Value?
 
 

7) What temperature (in degrees Celsius) corresponds with the Mean, the Minimum Value, and the Maximum Value?
 
 

8) What temperature (in degrees Fahrenheit) corresponds with the Mean, the Minimum Value, and the Maximum Value?
 
 

9) Load the image from 1992.  Repeat the directions above question 6, and answer questions 6, 7, and 8 for the 1992 image.  Fill in the table below with your answers.
 
 
1992 South Pacific Chart Data Number (Value) Degrees Celsius Degrees Fahrenheit
Mean: _ _ _
Minimum Value: _ _ _
Maximum Value: _ _ _
10) Which of the two years (1982 or 1992) was a cooler year in the South Pacific?  By how many degrees? (both Celsius and Fahrenheit)