Teacher Guide—Earth Science Module - Estuaries NOAA

Teacher Guide—Earth Science ModuleActivity 2: Salinity & TidesFeatured NERRS Estuary:Chesapeake Bay Virginia NationalEstuarine Research Reservehttp://nerrs.noaa.gov/Reserve.aspx?ResID=CBVActivity SummaryIn this activity, students learn about tides and salinity inestuaries. They observe time-lapse models of tides andsalinity distribution in the York River, part of theChesapeake Bay, VA NERR. Learn how salinity changeswith an incoming and outgoing tide, observing thedynamics of the salt wedge at various sites along the river.Students also make predictions about the salinitychanges at each site based upon their observations ofthe animation. They then use salinity data frommonitoring stations along the river to see changes duringa typical day. And, then describe the patterns of eachsalinity graph and compare the graphs.Learning ObjectivesStudents will be able to:1. Analyze different forms of data and synthesizeinformation to develop a hypothesis.2. Explain how tides and the geology of the estuaryaffect water circulation in an estuary.3. Describe daily patterns of salinity changes in theestuary.Grade Levels9-12Teaching Time3 (55 minute) class sessions + homeworkOrganization of the ActivityThis activity consists of 3 parts which help deepenunderstanding of estuarine systems:Tides in Chesapeake BaySalinity as York River Flows into the BayInteraction of Tides and River FlowBackgroundYork River is one of several riversflowing into Chesapeake Bay. As thenation’s largest estuary, ChesapeakeBay contains a diverse collection ofhabitats including oyster reefs, seagrassbeds, tidal wetlands, sandy shoals andmudflats. Chesapeake Bay and YorkRiver illustrate the complexities of tidalEarth Science Module—Activity 2