The Earth’s atmosphere is a kind of fluid that moves much like the liquid inside the Turbulent Orb exhibit, which was created for NCAR by the Exploratorium Museum. Atmospheric winds interact with the spinning Earth as they create complex circulation patterns. We know these winds as westerlies, easterlies, and trade winds in both the Northern and Southern Hemispheres.

Spinning the Turbulent Orb simulates the rotating Earth. As you spin it you can see various patterns, which are made by a soap-and-water mixture, that are similar to patterns observed in the atmosphere.

Understanding the general circulation of the atmosphere is fundamental in the work of many different areas of atmospheric sciences—to study hurricanes and the movement of pollution, for example. Scientists who mathematically simulate, or model, the global climate also need to incorporate this knowledge in their models. To read more about the Climate and Global Dynamics Division (CGD) and its work, go to, and to learn more about one such climate model, check out