Download First day of Spring Semester

Essential Question
I will be able to describe the chemical
properties of ocean water.
Warm up
Do you know anything about the earth’s oceans
Exit
What are two elements in the ocean
Homework
Page 422 Terms – define and give one fact
5/24/2017
Chapter 21.1 pages 407 to 412
5/24/2017
Notes Section 21.1
• Properties of Ocean Water
– Composition of Ocean water
• Rivers carry dissolved solids into oceans.
• Evaporation leaves behind salts and minerals.
• Gases enter the ocean from rivers, volcanoes
and the atmosphere.
– Elements in Ocean water
• Oceans are 96.5 % pure water
• 75 chemicals elements in oceans
• The six most abundant; chlorine, sodium,
magnesium, sulfur, calcium, & potassium
5/24/2017
Notes Section 21.1
– Dissolved Gases
• The principal gases are nitrogen, oxygen, &
CO2, CO2 most common.
• Temperature effects the amount of gas that
dissolves. Cold water is best.
• The gases can leave and return to the
atmosphere.
5/24/2017
Notes Section 21.1
– Salinity of Ocean water
• Most solids are salts, parts per 1,000
• Table salt, sodium and chlorine make up 78%
of solids in oceans.
• Salinity can be affected by amount of fresh
water and the temperature.
– Temperature of Ocean water
• Oceans absorb long, invisible infrared
wavelengths.
• The amount of infrared determines ocean
temperature.
• Ocean water freezes at -2 Celsius.
5/24/2017
Notes Section 21.1
– Surface temperature
• Water temperature is constant to about 100m
to 300m in depth
• Surface temperature does cool with latitude:
poles close to -2 Celsius, tropics around 30
Celsius
• In the mid-latitudes surface temperature varies
from 10 to 20 Celsius
5/24/2017
Notes Section 21.1
– The Thermocline
• The sun does not directly heat below the
surface, so temperatures drop sharply to about
5 Celsius
• It is caused by a difference in density
• Many lakes have this zone as well.
– Density of Ocean water
• Temperature affects density more than salinity
does
• The densest water is at the poles.
5/24/2017
Notes Section 21.1
– Color of Ocean water
• Color is determined by the way it absorbs or
reflects sunlight.
• Water reflects or absorbs the blue wavelength
last
• Light does not penetrate below the surface
levels and this area is in total darkness.
5/24/2017
Chapter 21.2 pages 413 to 416
5/24/2017
Notes Section 21.2
– Life in the Oceans
• Ocean Chemistry and Marine Life
– Plants and animals in the ocean help maintain a
balance.
– All elements in the ocean are part of the food chain.
– Deep water is storage for vital nutrients to support
life.
• Sunlight and Marine life
– All plants require sunlight and are restricted to the
upper 100 meters of water.
– Phytoplankton form the base for the complex food
web that support life.
– A benthos is something that lives on the ocean floor
of shallow waters.
5/24/2017
• Ocean Environments
– Two types – bottom and water
• Benthic zone or bottom
– Has five zones
– Intertidal zone – this the area between high
tide and low tide
 Mixed water, sunlight and nutrients
attached marine life to this zone
 I.e.. Crabs, clams, seaweed…..
– Sublittoral zone – submerged zone on
continental shelves
 Sea stars and brittle stars live here
5/24/2017
– Bathyal Zone – starts at the continental slope
to 4,000 meters
 Octopuses, sea stars…..
– Abyssal Zone – starts at the end of the
Bathyal zone and extends to 6,000 meters
 Sponges, worms…..
– Hadal Zone – in ocean trenches
 Unexplored.
5/24/2017
Notes Section 21.2
• Pelagic Zones
– It has two main areas
– First is the neritic zone.
• Located above the continental shelves
• Abundant sunlight, moderate temperature
and low pressure.
• Plankton and nekton fill this area and
make most of the sea food people eat.
5/24/2017
Notes Section 21.2
– The second is the oceanic zone
• This is the area below the continental
shelves and is divided into four areas.
– Epipelagic zone – upper zone, tuna,
dolphin and sargassum weed.
– Mesopelagic, bathypelagic, and
abyssopelagic make the rest. Marine life
decreases with depth.
5/24/2017
Chapter 21.3 pages 417 to 421
5/24/2017
Notes Section 21.3
• Ocean Resources
– Fresh Water from the ocean
• Three ways to remove salt (desalination) from
oceans
• Distillation – is a process in which water is heated
to cause evaporation and then pure water is
condensed from the vapor.
• Freezing – pure water freezes first and the salt
water can be removed, the pure water can now
be melted.
• Reverse Osmosis – salt water is pushed through
membranes that block the salt.
5/24/2017
Notes Section 21.3
– Minerals from the ocean
•Nodules are found on the abyssal plains,
they contain manganese, iron copper,
nickel, cobalt and phosphates.
•If a cheap method of recovery can be
found, they may replace some land based
mining.
•Some minerals we currently get from the
ocean are salt, magnesium, bromine and
oil from the sea bottom.
5/24/2017
Notes Section 21.3
– Food from the ocean
•Fish is a high protein food from the ocean
that is currently in decline.
•Aquaculture – is the development of plants
and animals to grow in the oceans.
•These farms would be susceptible to
pollution from land.
•These farms could one day produce more
food then land based farms.
5/24/2017
Notes Section 21.3
– Ocean-Water pollution
•As populations increase and dump more
waste into the oceans it will no longer be
diluted and absorbed.
•Coastal waters are at the most risk, these
are also the most productive.
•Pollutants have been detected in
measurable amounts everywhere in the
open ocean.
5/24/2017