Currents and Climate

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Standards
Science 6.4 d Students know the sun is the major source of energy for
Earth’s surface.
Science 6.4 e Students know differences in pressure, heat, air movement
and humidity results in a change in weather.
Reading Comprehension
-2.5 Comprehension & Analysis of Grade Level Appropriate Text -Clarify and
understanding of texts by creating outlines, logical notes, summaries, or
reports.
Language of the
Discipline
El Nino
La Nina
Salinity
Upwelling
Anticipatory Set
Once upon a time, a family was strolling along a
beach in Washington and noticed sneakers
covered the beach. They had been washed up to
shore. A few weeks later the same sneakers
showed up in Oregon. After that they showed up
in Hawaii! How is this possible?
Input/ Surface Currents
Affect water to a depth of several hundreds meters
are driven mainly by winds.
Currents are a large stream of moving water that
flows through the ocean.
Suns radiation is the ultimate source of energy that
powers global winds and surface currents in the
ocean.
Continentals blocks and redirect the flow of currents.
Coriolis Effects
Causes global winds to curve as a results of
Earth’s rotation
It causes surface currents to curve to the right in
the Northern hemisphere and to curve to the left
in the Southern hemisphere
Effects on Climate
Surface current warms or cools the air above it,
influencing the climate of the land near the
coast.
Winds pick up moisture as they blow across
warm water currents.
Cold water currents cool the air above them.
Cold air holds less moisture and brings cool, dry
weather to the land.
El Nino and La Nina
El Nino and La Nina are short term changes in
the tropical Pacific Ocean caused by changes in
ocean surface currents and prevailing winds.
Warm water event: El Nino begins with unusally
wind patters. It causes the ocean to become
warm.
Occurs every 2 to 7 years. Brings heavy rains,
flooding, and mudslides to California
El Nino and La Nina
La Nina when surface waters are colder than
normal. Brings colder than normal winters and
greater precipitation to the Pacific.
La Nina causes greater hurricane activity.
Deep Currents
Deep currents are caused by differences in the
density of ocean water.
Depends on temperature and salinity
The sinking of dense, cold water with high
salinity occurs in deep currents formed in the
oceans near the poles.
Global Conveyer Belt
Deep currents move and mix water around the world.
They carry cold water from the poles toward the
equator.
Deep currents flow slowly.
Moves water from the tropics towards the poles and
cold water to the equator.
Dense water sinks near the poles it spreads out and
mixes with surrounding water.
Upwelling
Upwelling brings up tiny ocean organisms, minerals,
and other nutrients from the deeper layers of the
water.
Occurs in the Pacific Ocean.
The movement of cold, deep ocean water to replace
warm water at the surface.
March- September
El Nino prevents upwelling from occurring
Modeling
Identify 5 key components that are important to
Currents and climates.
1. Surface currents are driven mainly by winds
2. Surface currents warms or cools the air around it
3. California Current and Davidson Current are two
important currents.
4. Continents block and redirect the flow of currents
5. Coriolis changes global winds
Checking for
Understanding
Identify 5 key components that are important to
El Nino and La Nina
Guided Practice
Independent Practice
Guided Practice – Worksheet #1-5
Stop! Raise your hand and have your answers
checked.
Independent Practice – Worksheet # 6-10
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