Earth’s Water Cycle for Middle School Students Global Precipitation Measurement Mission Developed by the GPM Education and Public Outreach Team NASA Goddard Space Flight Center

Guiding Questions The Big Picture: Why is it important to measure rain and snow around the globe? Earth’s Water: How much of Earth’s water is freshwater? Freshwater versus Saltwater: Which of these do we need for our survival? The Water Cycle: How does water move through the “water cycle? Precipitation: Where do rain and snow come from? Are these made up of freshwater or saltwater? GPM: How will the GPM mission measure precipitation all over the world? NASA and Earth Science: NASA is helping us learn about our home planet! 2

ENGAGE

Solid? Liquid? Gas?

Freshwater vs. Saltwater How much of Earth’s water is freshwater? We will make a model of Earth’s freshwater. 1.Take the plastic cup, and imagine that the cup is a model of Earth’s surface. 2.Fill up ~ 75% with water. This represents how much of Earth’s surface is covered with water. 3.Take out one eye-dropper of water, and place it in the small medicine cup. This represents how much of Earth’s water is freshwater- ~ 2.5% 4.Take one drop of this water- this represents how much freshwater is easily accessible to us!

Saltwater versus Freshwater

Water on Earth Credit: Earth Forum, Houston Museum of Natural Science

Where is our Freshwater?

The Big Picture The Freshwater Connection Link to GPM movie

How do we use freshwater? In addition to home use, fresh water is used for transportation, agriculture, heating and cooling, industry, livestock, and many other purposes. That one percent of water is primarily used in eight different ways, or categories: Domestic. Residential home indoor and outdoor use, such as drinking, cleaning, and watering lawns Public supply. Public and commercial buildings, such as schools and restaurants Irrigation. Watering systems for farms that grow food

Freshwater Usage Livestock. Watering systems for animals on ranches and farms Aquaculture- Watering systems for fish farms and hatcheries Industrial -Water used for manufacturing products, including food, paper, and petroleum products Mining- Water used for extracting natural resources such as metals, minerals, natural gas, and oil Thermoelectric- Water used for generating electricity using steam-driven generators

Estimated Water Use in US From the American Water Works Assoc. Thermoelectric 49% Public Supply 11% Domestic 1% Irrigation 31% Other- 8%: Mining 1%, Industrial 4%, Aquaculture 2%, Livestock 1%

Earth’s Water Cycle

The Water Cycle and NASA featuring-molecule-man featuring-molecule-man

Consider these questions- Where does the water cycle begin? Where did the water come from? How can we get more water into our water cycle? Does any water ever leave the water cycle? cycle cycle

Where did the water come from?

Earth’s Water We aren’t 100% sure! Let students research this topic and report in! Most experts think much of it came from space- comets and other objects hitting Earth during early formation Some may have been in Earth’s interior and in rocks and been outgassed from volcanoes as Earth began to cool. Some experts are thinking the solar wind’s interaction with Earth’s oxygen could play a part

Can We Get More Water? Recipe for water? Can people “make water”? What will happen as the glaciers and ice caps melt to our water cycle?

How Stuff Works- Manufacturing Water h/geophysics/manufacture-water.htm

Data Animation of Water Cycle 884/index.html 884/index.html

Animation of Fluid Circulation watering-land watering-land

Measuring Precipitation How do we know how much precipitation we receive? Ground-based measurements: rain gauges, radar Space-based measurements: TRMM and GPM

Overview: Global Precipitation Measurement The GPM Core Observatory will provide improved measurements of precipitation from the tropics to higher latitudes GPM is an international mission which will use inputs from an international constellation of satellites to provide improved space and time coverage of precipitation (rain, snow) over the globe

“For Good Measure” measure measure

What can we do with the data? Landslides Flooding Agriculture/Famine Early Warning Freshwater Availability Land surface and climate modeling World Health Extreme Events The rain and snow data gathered from the TRMM and GPM missions already provide and will extend our capabilities to study a wide range of applications for scientific research and societal benefit.