Outline factors that affect the depth of the photic zone What will be an ideal response?

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Sunlight has a difficult time reaching and penetrating the ocean; clouds and the sea surface
reflect light while atmospheric gases and particles scatter and absorb it. Once past the sea
surface, light is rapidly attenuated by scattering and absorption. Scattering occurs as light is
bounced between air or water molecules, dust particles, water droplets, or other objects
before being absorbed. The greater density of water (along with the greater number of
suspended and dissolved particles) makes scattering more prevalent in water than in air. The
absorption of light is governed by the structure of the water molecules it happens to strike.
When light is absorbed, molecules vibrate and the light’s electromagnetic energy is converted
to heat. Even the clearest seawater is not perfectly transparent. The thin film of lighted water
at the top of the surface zone is called the photic zone. In the very clearest tropical waters, the
photic zone may extend to a depth of 600 meters, but a more typical value for the open ocean
is 100 meters. In contrast, light typically penetrates the coastal waters in which we swim only
to about 40 meters (130 feet). All the production of food by photosynthetic marine organisms
takes place in this thin, warm surface layer. Here, the sun heats water, heat is transferred from
the ocean into the atmosphere and space, and gases are exchanged with the atmosphere. The
thermostatic effects function largely within this zone. Most of the ocean’s life is found here.
The photic zone may be extraordinarily thin, but it is also extraordinarily important.