Download Physics of Water Pictures and Readings

Figure 1. Temperature of the ocean with increasing depth
Taken from http://my.opera.com/nielsol/blog/2007/08/16/ocean-watermixing
Question: Why Is the Ocean Blue?
Answer: When sunlight strikes water, the top 50 meters absorbs nearly all of the
radiation that reaches the surface. This is why surface temperatures are warmer
than at lower depths.
Light can travel up to 200 meters in depth. Surface water (within 50 meters)
absorbs warm colors, like reds and oranges (long wavelength light). But, bluish
light, with shorter wavelengths, continues to travel further down into the water
column. Therefore, it is blue light that is scattered and reflected back. So, blue
light travels further through water than red, orange, yellow, and green light. No
light at all penetrates beyond 2,000 meters (3,280 feet).
If one was to take a red object under water with them, the deeper they would
descend, the less red it will appear. This happens because there is a decreasing
amount of red light available to reflect back to your eye. Remember that a red
apple appears red because it absorbs all other colors and reflects red light. If there
is no red light available, the apple will look gray or black.
See link below for an illustration of the depth at which different colors of light are
absorbed.
http://oceanexplorer.noaa.gov/explorations/04deepscope/background/deeplight/media/diagram3.html
Written portion compiled by Elena Duduk from multiple, unknown sources.
Light and the Ocean Zones
The ocean is divided into three zones beginning from its surface to its furthest depth. The three
zones are the following and possess the attached characteristics:
1. Sunlit Zone (Euphotic zone)
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Nearest to the surface
About 90% of marine life exists in this zone
Photosynthesis occurs in this zone due to enough light being able to penetrate water
Depth ranges to 600 feet below sea level
2. Twilight Zone (Disphotic Zone)
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Little light
No plants
Depth ranges from 600-3,000 feet below sea level
3. Midnight Zone (Aphotic Zone)
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90% of ocean exists in the Midnight Zone
No light exists
Near freezing temperatures
Little aquatic life forms
The above information was taken from the following web link. See this resource for more
information and graphics on each of the zones described.
http://www.mbgnet.net/salt/oceans/zone.htm