Download Properties of ocean water

Ocean Water
Earth Science II
(Session 14)
Introduction
• The oceanic microflora produces most of
oxygen that we breath.
• 90% of the Earth´s Oxygen comes from
Marine photosynthesis by phytoplankton
and algae.
• Through the water cycle, the oceans purify
the atmosphere and constitute an
immense space for marine life.
Origin of the oceans
• In its beginnings, the Earth was surrounded by
great volcanic activity throwing rocks and gases that
later gave origin to the atmosphere.
• With time, the Earth’s surface cooled enough so
that the water vapor was condensed and formed
water drops that fell on Earth in form of rain during
thousands of millions of years.
• The rain water formed rivers and water streams
initiating the formation of oceans.
Properties of ocean water
Salt (Sodium chloride, sodium
bromide and fluoride. Calcium
potassium, carbonates and
magnesium, etc.)
Density
Dissolved gases (Oxygen and Carbon
dioxide)
Boling Point
Freezing Point
Data
34.5 g/Kg
1.026 - 1.028 g/cm³
Variable
More then 100oC
Less then 0oC
DiSpezio, Michael , et al. (1999)
Physical properties
Marine organisms
• The organisms that habitat the oceans use
substances of the ocean water as nutrients and
to obtain energy.
• Many of these organisms depend on solar light
and because of this they need to live on the
superficial waters.
• The density of the ocean water also affects the
organisms that live in the ocean.
Distribution of life in the oceans
Organism's
Euphotic (500 m) also called
the Sunlight Zone
Seaweed
Zooplankton & plants
Fish
Marine mammals
Dysphotic (1,000 m) also
called the Twilight Zone
Fish
Mollusks
Aphotic (up to 6,000 m) this
latin word mean “no light”
Worms
Gelationous bodied
Gutiérrez, M. (1996)
Ocean zones
Gutiérrez, M. (1996)
Distribution of life in the
oceans
• In the ocean, the same phenomenon of
the food chain as what occurs on the
Earth’s surface occurs.
• Predator fish, eat smaller fish. Small fish
eat smaller organisms. Small organisms
eat micro organisms…..and so on….
Facts
• Most of the life in the ocean is found in the
Euphotic zone. This layer is also the
smallest.
• Many fish and mammals use
countershading to disguise themselves.
Their backs are dark and their bellies are
light
Things to Think about
• Dysphotic Zone….there is no photosynthesis
here…why?
• What mechanism do organisms use in to create
light?
• What is the relationship between pressure and
temperature in the ocean?
• What are the factors that affect the oceans
density?
Physical Properties
• The surface zone is
heated by solar energy
and mixed by the wind.
• The warmest water and
the least dense water is
found in the surface
zone.
• Surface water temps can
vary from 28°C near the
equator or -2° near the
poles.
http://www.bigelow.org/collaboratory/images/Thermocline.jpg
Thermocline
• Occur when water
temperatures decrease
rapidly.
• Are formed becuase warm
surface water floats on top
of the colder water
• The depth of the
thermocline can vary due
to location or season
http://www.bigelow.org/collaboratory/images/Thermocline.jpg
Reading in class
• From the textbook…
– Science and Technology: Drinkable Ocean
Water.
– Page 342
Bibliography
• DiSpezio, M. et al. (1999) Science
Insights: Exploring Earth and Space. 1st
ed. United States of America: Prentice
Hall.
• Gutiérrez, M. (1996) Ecology: Lets Save
the Planet Earth. 1st ed. Mexico: LIMUSA.