Scholastic's The Magic School Bus Teacher FeatureMicroscope

Have you ever wondered how rain is made? To find out, the Friz and her class boarded the Magic School Bus and headed to Atlanta, Georgia, home of The Weather Channel. There they met Nick Walker, the "Weather Dude," an on-camera meteorologist. Nick sat with Ms. Frizzle and told her all about the water cycle. Here’s how the conversation went:

Ms. Frizzle: How is water related to weather?
Nick: In order to have weather, you need to have water in the atmosphere. That’s one of things that make our planet unique. We are able to have water in our atmosphere in three different forms - solid (as ice), liquid, and as a gas (water vapor). As a liquid, water is found in the oceans, rivers, and lakes. Water vapor is in the air all the time, even though you can’t see it or feel it. In the clouds in the sky we have water in both a liquid form, and a solid form. Clouds may be made of just water, just ice, or both ice and water.

Ms. Frizzle: What is the water cycle?
Nick: The water cycle is the transfer of liquid water on the earth, in oceans, lakes, rivers, and ground, into a gas form, water vapor, and then the transfer of the water vapor back into liquid form as rain or snow. Really it’s the recycling of the water that’s on the earth. When you think about it, there is no new water, it’s the same water that’s always been here for thousands and thousands of years, recycling itself into different forms.

Ms. Frizzle: What are some weather conditions that demonstrate the water cycle?
Nick: Everybody has gone out after a rainy night, and they see that everything is wet. Then later during the day, you notice everything is no longer wet. Where did that water go? Well, through evaporation, it turned into a gas, water vapor in the air. Evaporation is the process in which water becomes a gas. Air will often rise, and as it rises it takes the water vapor with it. It goes up high into the sky where it’s cool. Cool enough where it will turn the vapor back into a liquid form or an ice form and that forms the clouds. This process is called condensation. Eventually, the drops of liquid or ice cling together and get bigger. Then they get heavy and fall to the ground as snow or rain. The snow or the rain is the precipitation, and that’s the third part of the water cycle. And then the cycle starts all over again and keeps going and going and going.

Ms. Frizzle: How does water evaporate?
Nick: Water evaporates when the sun heats it. The sun will actually cause the water molecules to separate from one another. Liquid water is basically water molecules that are very close together. When the sun heats it, the molecules become less crowded, so there is more space between the molecules. That’s when it becomes a gas. Wind can also cause these molecules to separate.

Ms. Frizzle: Are there other forces in the atmosphere that are necessary to complete the cycle?
Nick: Yes, the air has to rise. That involves pressure in the air. You don’t actually think about the air having weight, but there are different areas around the earth where the air weighs more or less, and these areas are constantly changing. We refer to an area where the air weighs a lot as an area of high pressure, and an area where the air weighs less, as an area of low pressure. When you have an area of low pressure, the air doesn’t weigh much so the air will rise.

About Nick Walker

Nick is an on-camera meteorologist for The Weather Channel, and can be seen in the late afternoon and evening broadcasts. Prior to joining The Weather Channel, Nick was at KSTW-TV and KIRO-TV in Seattle. His 20+ years in broadcasting also includes work as a news anchor and reporter at KSNW-TV in Wichita, Kansas, and KVUE-TV in Austin, Texas.

Nick is a member of the American Meterological Society and the National Weather Association, where he holds the NWA television Seal of Approval. He also received the 1993 Washington Press Award for weathercasting.

Nick is extremely active in educating kids about weather. Nick is the author of "Weather Dude: A Musical Guide to the Atmosphere," a book and musical cassette for children. He has appeared in numerous local and national magazine publications, and has been active as a speaker for schools and community groups. Nick has recorded several albums of original music as a singer and songwriter.

Back to "Kicks Up a Storm" Page

Back to Teacher Feature