Study Questions — Water
Lectures 7b and 7c
1) Why does clear ocean water appear blue? Discuss is terms of absorption and
scattering.
2) At what wavelengths are located the two most important water absorption bands in the
reflective infrared? List the wavelengths of three relatively minor water absorption
bands. (Hint: see slides 12 and 13 of Lecture 7b – water)
3) What is the best wavelength range for distinguishing land from water?
4) Select the wavelength bands for mapping ocean depth on shallow reefs. How would
you estimate ocean depth using these bands?
5) How would you modify your band selections in order to obtain data that would allow
your colleague to test the hypothesis that slightly elevated water temperatures are the
cause of the world wide decline of coral reefs?
6) What is El Nino? La Nina? How did remote sensing contribute to our understanding
of these two natural phenomena?
7) What color is river water having a high concentration of suspended sediments? What
color is this water in color infrared film? What color is clear water in color infrared film?
8) There is a national agricultural program to reduce the sediment eroded from crop and
forest lands and transported to the ocean by rivers. If you were the manager of this
program at the USDA, what specific actions would you suggest to growers and foresters?
9) Is it possibly to estimate the concentration of sediments suspended in water? What
type of sensor would you use?
10) What is SeaWiFS?
11) Explain briefly how to estimate chlorophyll concentrations in the open ocean.
12) Why is water vapor sometimes (correctly) said to be ‘the most important green house
gas?’
13) What is the latent heat of vaporization? How does the latent heat of vaporization
affect cloud dynamics?
14) What is Mie Theory? What is the most important assumption that Mie made to
derive his theory? Of what value is X, the size parameter in Mie Theory?
