Study Questions – Lecture 7a - Water
1) Describe the hydrological cycle.
2) Provide examples of remote sensing related to liquid water, water vapor and clouds
and snow.
3) How does water absorb incident light?
4) What is the wavelength at which water absorption is minimum? What color does this
wavelength correspond to?
5) Why does water appear blue? Scattering is more important in which wavelength
range? What effect does the presence/absence of multiply scattered light have on its
reflectance?
6) In satellite and aircraft data, the apparent total radiance of a water body is the sum of
what four radiances?
7) There is one meter of water covering an ocean coral reef. The coral should be visible
in which Landsat TM bands? Why? If there are 10 meters of water covering a coral
reef, in which Landsat TM bands should the coral be visible? Why?
8) How deep in the water column does the thermal band in a satellite sea surface
temperature sensor measure?
9) Explain how to use Planck’s equation and the bandpass of a thermal sensor to estimate
the sea surface temperature.
10) What is emissivity? What is the emissivity of water?
11) What is the importance of sea surface temperature in a weather model? In a climate
model?
12) Describe the spatial variation of sea surface temperature during an El Nino year.
During a La Nina year. In each of these climatic extremes, what is the direction of the
prevailing winds? In each where have the prevailing winds moved the warm water?
13) What is the significance of the name El Nino? Explain the link between El Nino, the
food source for anchovies and prosperity of Peru’s fishing community.
14) What is DOM?
15) In color IR film imagery, what color would you expect the Mississippi River to
appear, a river containing large amounts of inorganic suspended sediments and
dissolved organic matter? In color IR film what color would you expect a river
