HMH Florida Science Grade 6: Unit 3 - Lesson 5
What affects surface currents?
Continental deflections, Coriolis Effect, and Global winds.
What is a convection current?
a combination of surface and deep currents that work like a convection belt and distribute energy in the form of heat throughout the ocean
What is more dense, colder water or warmer water?
colder water
Global ocean currents distribute what two things all around the Earth?
energy and matter
What can push ocean water across the Earth's surface to create surface currents?
global winds
What kind of energy do ocean currents transport?
heat from the equator
What three spheres does an upwelling involve?
hydrosphere, biosphere and atmosphere
How does the sun power surface currents?
it causes difference in temperature across Earth, which causes differences in air pressure, which causes winds, and the winds create surface currents
In the southern hemisphere the Coriolis effect cause the currents to be deflected to the right or left?
left
Does higher salinity make water more or less dense?
more
What are deep currents?
movements of ocean water below the surface caused by differences in density
What does the water from the deep ocean supply?
nutrients from the decay of marine organisms
What do the nutrients from the deep ocean water supply with food?
plankton and other marine organisms
In the northern hemisphere the Coriolis effect causes the currents to be deflected to the right or left?
right
What two things cause differences in water density?
salinity and temperature
What two things combine to make global ocean circulation?
surface currents and deep currents
Coriolis effect
the deflection of moving objects from a straight path due to Earth's rotation
What is upwelling?
the process in which winds blow warm water away from a shore which allows cold water from the deep ocean to rise
What is the major source of energy that powers surface currents?
the sun
When surface currents meet continents they are deflected and change direction. True or False?
true
What are some examples of the kinds of life that ocean currents can carry?
turtles, coconuts and phytoplankton
How do convection currents transfer energy?
water at the ocean's surface absorbs energy from the sun which can be carried to cooler regions
What kinds of matter does ocean water transport?
water, solids, nutrients and dissolved gasses
When do deep currents form?
when water at the ocean surface becomes dense enough to sink far below the surface
Is the water from the deep ocean nutrient rich?
yes
