Human: What is the difference between a tornado and a funnel cloud? Assistant: 
The main difference between a tornado and a funnel cloud is that a tornado is a rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud, while a funnel cloud is an isolated rotating column of air that is not in contact with any other clouds. Tornadoes are usually much more destructive than funnel clouds as they can cause widespread destruction due to their strong winds and heavy rainfall.