Oceans and Climate
The global conveyor belt of ocean currents moves ocean water of different density and temperature through all of Earth's ocean basins in one giant loop. Which example also could be used to explain this movement of water?
a roller coaster that starts high, travels across the park as it swoops down, and rises back up again as it returns to the starting point
Millions of years ago, Earth's continents were in different places than they are today. Which statement is probably true about ocean currents millions of years ago compared with today?
Both surface currents and density currents would have different routes.
Your lab group has been assigned the job of making a model to show how ocean water circulates around Earth. Which variable is most important to correctly model this action?
Factors A, B, and C are equally important because each contributes to the circulation of ocean water.
Sylvia is writing a cause and effect report on ocean currents. Which statement can she use correctly in her report?
Global winds pull surface ocean water into the major ocean currents observed today.
Patrice has drawn a flow chart to explain how ocean currents help climates develop. Box 1 states: The temperature of the ocean water is determined by where the ocean currents begins. Box 3 states: The temperature over the land is determined, in part, by the temperature of the air mass above it What information should she put in Box 2?
Heat energy is transferred between the ocean water and the air mass above it.
Upwellings happen where cold water that first sank at the poles and traveled along the ocean floor rises to the surface. Upwellings bring nutrients to the surface, where they support communities of sea life. What might happen to the sea life around upwellings if all sea ice melted, and the ocean became the same temperature?
If the ocean became the same temperature throughout, upwellings would no longer happen. Sea life that depends on the nutrients brought up by the upwellings would move away or die.
There are four students in your group. Each student has a different explanation for why it is colder at the poles than it is nearer the equator. Which of your explanations is correct?
Julio says that it is colder at the poles because Earth is tilted on its axis, and the sun's energy is spread out over a larger area nearer the poles.
Your homework assignment is to draw the major ocean currents on a blank map of Earth. Your classmate says that he is going to simply copy the global winds onto the map. Will his map be correct?
No, because the ocean currents must also flow around the continents, which cause them to change direction.
Why does an increase in salinity cause a density current to form?
Saltier water is higher in density than fresh water. This water then sinks to the bottom, forming a current.
Your lab group has designed a model to teach younger children how the ocean current temperature changes with latitude and the effect this has on Earth's climates. In a large plastic pool, you have made a map of Earth, complete with North and South Poles and the equator. There is a heat lamp shining on the equator. What ocean current concept are you demonstrating by floating a large piece of ice toward the equator in the pool?
Surface currents travel only in one direction-- that is toward the equator.
The Dead Sea is a salty lake in the Middle East. Even though it is surrounded by land, it is below sea level. Water in the Dead Sea is about 10 times more salty than the average water in the world's oceans. What would happen if you poured water from the Dead Sea into ocean water at the same temperature, and why?
The Dead Sea water would sink into the ocean water because it is saltier and therefore denser.
When the oceans first formed on Earth, the water was not as salty as it is today. Based on this information, which statement could logically follow?
The average density of the ocean water was lower than it is today.
The current that moves south off the coast of California is a cold-water current. Suppose this current flowed north and originated further south, near the equator. What statement could be true?
The coastal California climate would be warmer than it is today.
Chantelle wants to model how the surface ocean currents have changed during Earth's long history. Which of these explains why Chantelle would need to use maps of Earth throughout different times in our geological history?
The continents have moved over time. And the ocean currents are influenced by the position of the continents.
Constant westward winds drive the Antarctic Circumpolar Current, which completely circles Antarctica. How would this current be different if there was a land bridge between the southern tip of South America and Antarctica?
The current would flow north into the Pacific after hitting the land bridge.
Your friend Clarence is moving from an inland city to a coastal city that is near a cold ocean current. Which statement would give Clarence the best advice about what to expect?
There will be a mix of warm and cool weather and a lot of fog.
Scientists think that ancient ocean travelers knew about Earth's ocean currents. Which would not have been a benefit from this knowledge?
They could have avoided areas of bad weather.
Your lab group is presenting a model showing how salinity affects ocean currents You have brainstormed four different scenarios. Which one is best for your model?
You gradually pour a beaker of salt water into a beaker of fresh water.
Ben's family went to Virginia Bench, VA, for their summer vacation. Steve's family went to San Francisco, CA. The went at the same time. While Ben swam in the ocean everyday, Steve stood on the shore shivering in the cold surf. Both cities are located about 37 degrees north latitude. Why was Ben able to swim comfortably while Steve could not?
cold water currents from the northern Pacific Ocean make the water along the California coast too cold to swim in
Which ocean travelers would benefit most from the Gulf Stream?
racing sailboats traveling from Miami Bench, Florida, to Virginia Beach, Virginia
