1Why is snowimportant in thesouthwesternUnited States?Investigation OverviewIn Investigation 4, students role-play U.S. senators from seven westernstates seeking to find solutions to important water problems in theSouthwest: recurrent drought, which reduces vital snowpack resources,in the face of rapid population growth and therefore increasing demandon those resources. Information from satellite images, in tandem withground-based perspectives, assist students in playing their roles assenators. Because the investigation uses a case study in the UnitedStates, all statistics will be in English units. This conscious exception tothe standard use of metric units reflects the real-world practice of Ameri-can water resource managers.Time required: Five to nine 45-minute sessions (as follows):Introduction and Parts 1 and 2: One or two 45-minute sessionsPart 3: One 45-minute sessionParts 4 and 5: One or two 45-minute sessionsParts 6 and 7: One or two 45-minute sessionsPart 8 and Debriefing: One or two 45-minute sessionsMaterials/ResourcesBriefing (one per student)Log (one per student)Computer with CD-ROM drive. The Mission Geography CD containscolor graphics that contain data needed for the investigation.Access to an atlas with an index to show location of cities in the westernUnited StatesOptional: Access to the Internet, which offers opportunities for extendingthis investigationContent PreviewThe southwestern United States faces critical water shortages. TheSouthwest is the driest quarter of the United States and yet its populationis growing faster than that of any other region. Most of the populationdepends upon mountain snowmelt for its water supply, but the amount ofsnow varies, and the climate is subject to recurrent droughts. Theallocation of water among both competing uses and areas is a hugepolitical and management problem.Geography StandardsStandard 7: Physical SystemsThe physical processes that shapethe patterns of Earth’s surface• Describe how physical processesaffect different regions of the UnitedStates and the world.Standard 15: Environmentand SocietyHow physical systems affecthuman systems• Analyze examples of changes in thephysical environment that havereduced the capacity of the environ-ment to support human activity.• Apply the concept of “limits to growth”to suggest ways to adapt to orovercome the limits imposed onhuman systems by physical systems.Standard 18: The Uses ofGeographyHow to apply geography to inter-pret the present and plan for thefuture• Develop policies that are designed toguide the use and management ofEarth’s resources and that reflectmultiple points of view.• Analyze a variety of contemporaryissues in terms of Earth’s physicaland human systems.Geography SkillsSkill Set 4: Analyzing GeographicInformation• Make inferences and draw conclu-sions from maps and other geo-graphic representations.Skill Set 5: Answering GeographicQuestions• Evaluate the answers to geographicquestions.Module 1 Educator’s Guide Investigation 42Classroom ProceduresBeginning the Investigation1. Tell students that in this investigation they will playthe roles of senators from seven western states onthe Senate Subcommittee on Future Water Policyin the Southwest. Generate initial discussion byasking questions such as:• Why might there be a need for changing waterpolicies in this region?• What kinds of issues might you expect to face indoing this?2. Organize for cooperative learning by formingstudents into seven small groups:• Form a small group for Arizona, California,Colorado, Nevada, New Mexico, Utah, andWyoming.• Give students some choice of group, randomlyassign, or count off by seven.• All groups do not need to be the same size:assign larger groups to the more populousstates (California is by far the largest, followedby Arizona and Colorado; Wyoming has thesmallest population).• Students help each other in their small grouplearn to play the role of their state’s senator.(Cooperative learning will be completed in Part 8when students from each group come together ingroups of seven to formulate recommendations.)3. Hand out copies of the Briefing and Log to eachstudent. (Alternative: If you don’t want eachstudent to complete a Log, hand out only one copyper group.)4. Have students look over the Briefing and Log andemphasize• the importance of studying the images (calledfigures) that support the written material;• the questions and the need to write out answerson the Log (answers are provided at the end ofthis Educator’s Guide); and• the schedule for handing in answers on the Log,either all together at the conclusion, or one ortwo at a time as they complete individual parts ofthe investigation.5. In their small groups,• have students read Background, Objectives,and Scenario;• take any questions they may have; and• tell them they should begin working through theBriefing in their small groups—reading, studyingthe figures, discussing, and answering the Logquestions.6. For students who do not live in the Southwest, ask:Why would you care about this region’s waterproblems? Student responses might include• the Southwest provides fresh fruits and veg-etables to the rest of the country;• the economic burdens caused by regionalproblems, such as drought or flooding, are oftenborne by the rest of the country through federalassistance; or• you should care about the problems of people inother places.Developing the Investigation7. Beginning with Part 1: Why is this investigationimportant?, small groups can work through thematerial on their own.• If you want to keep the groups progressing atabout the same pace, you might conduct wholeclass discussions on interesting and difficultpoints and/or of the Log questions.• From Part 1, for example, you might check forunderstanding of the concept of reservoirstorage and hydropower by asking: “How issnow used to make electricity?” and “What ismeant by the phrase water-stressed areas?”• The first Log question comes at the end of Part2. Remind students that in answering the Logquestions carefully, they are preparing to playtheir roles as members of the Senate Subcom-mittee on Future Water Policy in the Southwest.8. At the beginning of Part 3: How much do cities inthe Southwest depend on snow?, Question 2directs students to complete the table in the Log.The table is designed to help students organize theinformation in Part 3 as they cover it.• Students should