Presentation on theme: "Ocean Currents 1.What is the cause of various kinds of oceans currents? 2.What is the impact of ocean currents on the transfer of energy around the globe?"— Presentation transcript:
Ocean Currents 1.What is the cause of various kinds of oceans currents? 2.What is the impact of ocean currents on the transfer of energy around the globe?
Day 1: Surface Currents 1. Surface Currents These waters make up about 10% of all the water in the ocean. These waters are the upper 400 meters of the ocean. Caused by the friction between the ocean and wind that blows across its surface. These currents are closely related to global wind patterns
Day 1: Deep Water Currents 2. Deep Water Currents— These waters make up the other 90% of the ocean Deep waters are "formed" where the air temperatures are cold and where the salinity of the surface waters are relatively high. The combinations of salinity and cold temperatures make the water denser and cause it to sink move along the bottom.
Surface and Deep-Sea Current Interactions Unifying concept: “Global Ocean Conveyor Belt” Warm, surface ocean currents flow toward the poles before sinking and deeper, colder ocean currents flow toward the equator before rising. http://seis.natsci.csulb.edu/rbehl/ConvBelt.htm
Day 2: Upwelling Upwelling along the coast is caused when waters are moved offshore by wind and are replaced by waters from below. This brings cold, nutrient rich waters to the surface, making them good habitats for marine organisms. Upwelling is common along the west coast of the U.S. and South America
Day 2: Question What do you think causes downwelling? When winds causes warm water to move towards shore causing water to sink?
Day 3: Coriolis Effect The Earth’s rotation causes the surface currents in the Northern Hemisphere to rotate to the right and to rotate to the left in the Southern Hemisphere
Day 3: Activity Experience the Coriolis Effect. Get out a piece of paper, turn it sideways and put a line down the middle representing the equator. Have a partner pull the paper left to right as you try drawing a straight line from the equator to the North. Which way does your line bend? Repeat the above but this time try drawing a straight line from the equator to the South. North South Equator
http://earth.usc.edu/~stott/Catalina/Oceans.html DAY 4: Surface Currents and Climate
Day 2: Questions Based on the previous slide 1.In general, in which direction do cold and warm ocean currents flow? 2.Which country would you expect to have a warmer climate, Canada or Great Britain? Explain why? 3.Do ocean currents play a role in distributing heat around the world? Explain why?
Day 4: Answers 1.Warm current flow from the equator toward the poles. Colder currents from poles toward the equator? 2.Despite having the same latitude as Canada, Great Britain has a fairly mild climate because the Gulf Stream carries warm water from the equator up to Northwestern Europe. 3. Ocean currents distribute excess heat from the equator to the cooler, higher latitudes.