What are air currents? Air currents are like rivers of wind caused by areas of high and low pressure.The air above the land is warmer and less dense, so it rises. The air over the water is cooler and heavier. The cool air rushes in toward the low-pressure zone over the land, forming a lovely sea breeze. But what about Jet Streams? In this episode of Crash Course Kids, Sabrina chats with us about all things relating to Air Currents.

This page is part of NASA's Earth Observatory website. It features text and a scientific illustration to describe how the ocean interacts with the atmosphere, physically exchanging heat, water, and momentum. It also includes links to related data sets, other ocean fact sheets, and relevant satellite missions.

In this activity, students learn about ocean currents and the difference between salt and fresh water. They use colored ice cubes to see how cold and warm water mix and how this mixing causes currents. Also, students learn how surface currents occur due to wind streams. Lastly, they learn how fresh water floats on top of salt water, the difference between water in the ocean and fresh water throughout the planet, and how engineers are involved in the design of ocean water systems for human use.

Students develop their understanding of air convection currents and temperature inversions by constructing and observing simple models.

This resource uses text, images, maps and a laboratory exercise to explain how differences in the temperature and salinity of ocean water cause the formation of deep-ocean currents. It is part of the Jet Propulsion Laboratory's "Ocean Surface Topography from Space" website. This material is also available on the "Visit to An Ocean Planet" CD-ROM.