Julie works at a place called the United States Polar Rock Repository. It is a place that stores rocks from the Arctic and Antarctica. It is a library of rocks! Julie takes pictures of the rocks that are sent there. She writes descriptions of them. She labels each rock so it can be stored. But what she likes the most is sharing the rocks with other people.
This black, crumbly rock from the continent of Antarctica is coal. Coal is a fossil fuel. It is formed from trees and plants that died and fell to the ground. Over millions of years, the plants broke down and became packed together. Over time, the tightly packed plants became coal.
But wait! Why is there coal in Antarctica? There are no trees and not many plants there. Most of Antarctica is a cold, frozen desert.
Julie knows that rocks can tell a story. The coal tells us that Antarctica was very different long ago. There was no ice or snow. Antarctica was warm and covered by swamps and forests.

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