Sorry, you need to enable JavaScript to visit this website.
Skip to main content


Knows that the solid Earth is layered with a thin brittle crust, hot convecting mantle and dense metallic core; three-fourths of the Earth's surface is covered by a thin layer of water; and the entire planet is surrounded by a blanket of air.

Ice Sheets and Sea Level Rise

The ice sheets of Greenland and Antarctica contain massive amounts of frozen water (i.e., ice) that, if broken off or melted, for instance from extended global warming or from outward ice flow, would go largely into the oceans. In view of the vast size of the oceans, covering over 70% of the Earth's surface area, many people might at first think that the addition of ice or melted ice from the ice sheets would have little impact on global sea level.

View the full Example

How Thick is the Atmosphere?

We've all seen pictures of the Earth and its atmosphere as a series of concentric circles, showing the troposphere, stratosphere, ionosphere, etc., often looking like a bullseye target with the solid Earth in the middle. But if we were to draw that picture to scale, what would it really look like?

View the full Example

Could a World of Swimmers Raise Sea Level?

In the state of Maryland, a local politician claimed that sea level is rising because there are too many people putting boats on the open ocean! This is a true story! Is this or similar claims possible? Imagine if all of the people in the world agreed to go float on the ocean at the same time! Could that result in a significant sea level rise, perhaps even destroy low-lying nations such as Bangladesh?

View the full Example