18 Fast Changes on Earth

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Fast Changes on Earth by REYNA EISENSTARK

Chapter 1 Fast Changes on Earth Look outside. It probably looks as it did yesterday. This is because most changes on Earth happen slowly. There are fast changes on Earth, too. A bad storm can come out of nowhere. A small stream can grow into rushing water. We don't always know when fast changes will happen.

Chapter 2 Fast Water Have you ever filled a sink with too much water? If the water spilled over, there was a flood. A flood is when water overflows. It can happen during a heavy rain. It can happen when snow melts too quickly. Some floods cause damage. They tear down trees. They harm buildings and people, too.

Chapter 3 Twister! Many storms bring rain and wind. Sometimes they cause tornadoes. A tornado is a fast, spinning cloud of air. It is also called a twister. Tornadoes are wide at the top and thin at the bottom. Tornadoes have very strong winds. In 1999, one tornado after another hit Oklahoma. They were the strongest tornadoes ever!

Chapter 4 Shaky Cround If the ground under you starts to shake, it could be an earthquake. Scientists want to learn all about earthquakes. Most earthquakes do not last long. But they can be dangerous. In 1906 an earthquake destroyed most of San Francisco. It lasted for only 50 seconds!