Ocean Currents Critical Thinking:
- Read more about Thermohaline Circulation and identify the two places in the world that generate the thermohaline “conveyor belt” of the world’s oceans through cold water sinking. You can learn more about the global conveyor belt by watching this video (click here).
- Take a visit to Earth: a visualization of global weather conditions. Find any place in the Northern Hemisphere where you see lots of wind movement. Open the overlay menu in the lower left and select Mean Sea Level Pressure (MSLP.) Notice the scales they give you, white for high pressure, and purple to red for low pressure. Describe how air moves in or around a white high pressure cell. Describe how air moves in or around a red low pressure cell. Finally, does air move from low to high pressure or from high to low pressure.
- Using the Earth site above, zoom out a bit to look at the entire Pacific Ocean. Which direction does wind generally move on either side of the equator? Is this also true in the Atlantic? These winds are known as the Trade Winds. Using the term Coriolis Force, describe what drives the Trade Winds.
- Examine the graph at the top of the page. Use the data from September 16th and 17th on that graph to describe the relationship between dropping air pressure and changing wind speed. If you prefer, you can use the data in the graph to describe what makes wind blow.
- Let’s use Earth again. Take a view of the North Atlantic, use your over lay menu to view ocean, currents, and sea surface temperature (SST.) Warm water currents flow from the equator towards the poles. What effects do warm water currents such as the Gulf Stream have on the temperature of the lands they move towards?
- Kayak Island located in the Gulf of Alaska is nearly uninhabited and really remote. Explain why its beaches are covered in plastic trash. You may want to use this helpful site.
- Ever heard of the Great Pacific Garbage Patch? A floating patch of garbage the size of Texas? Watch the SciShow video on YouTube and explain how movement of large ocean gyres have concentrated huge masses of human garbage. If you get stuck, I would also encourage you to checkout gyres.org for additional explanation.
- Do your best to explain Ekman transport in your own words. The link should be helpful.
- Explain how offshore blowing winds create up-welling, and how up-welling create ideal conditions for plankton blooms. I tried to create a model of this in class using a fish tank, frozen food coloring, and a fan. See if this model helps.
- One area of the Pacific that experiences regular upwelling is the coastline of Peru. This happens when winds blowing from the south to the north move water off shore. Go to Earth, are the winds currently blowing towards the North along the coast of Peru? If so, is it likely the coast is experiencing upwelling? Can you see it if you switch to ocean (and SST)?