Develop and use a model to describe the role of gravity in the motions within galaxies and the solar system.
You may be familiar with ice cubes in your favorite soda, but do you know there are very big ice cubes (scientists call them glaciers) hundreds to thousands of meters thick, lying in places
with high mountains? These glaciers shaped beautiful landscapes all around the world — from Glacier National Park to Yosemite, from Patagonia in South America to the Himalayas in Asia.
Did you know that a quarter of the world’s population gets drinking water from karst aquifers? Karst is the type of landscape that forms by dissolution of carbonate rocks (limestone, dolomite) or other highly soluble rocks such as evaporates (gypsum and rock salt). Karst includes caves, sinkholes, sinking streams, and springs. Karst environments are vulnerable to groundwater contamination. Understanding groundwater flow in karst terrains is critical for safe drinking water.
After rain falls on relatively high land, it moves downwards into drainage areas called watersheds. You will create a model of a watershed by spraying rain on a plastic cover representing Earth’s surface. By watching how it flows, you can identify drainage divides and learn about the movement of water.
Even though our home planet has a lot of water, over 73 percent of that is salt water. We need freshwater to meet most of our needs, and precipitation supplies much of this valuable natural resource. Did you know that NASA, in a partnership with the Japanese, has a satellite that measures precipitation as it falls from the clouds to the ground?
Watersheds can be as small as a lake or thousands of square miles. The natural or human-made surface of the land and the sediments and rocks below are all part of a watershed. Rainfall
supplies watersheds, and water moves across the surface or infiltrates and moves through the ground.
In this activity you will use a computer model to explore the movement of water within your watershed.
• Computer with internet