Sequence | Background | Objectives | Materials | Activity | Extensions | Evaluations

TOPIC-TITLE Physical Parameters - Sea Level Rise AUTHOR Michael Duffy Edward Pasek Madelyn Charlton Allen Ross Hobbs Rosemarie Buote GRADE SUITABILITY Middle School SCOPE Geology

Sequence You may present sea level rise to students in either 7th grade Life Science or 8th grade Earth Science before or after studies of the greenhouse effect or global warming. You can examine depletion of the ozone layer relative to the greenhouse effect and the periods of glaciation followed by warming trends throughout the Earth's history. < < go top

Background Summary Research has demonstrated a relative rise in sea level in the last century at a number of locations around the globe. This expansion is believed to be the result of the Earth's increased surface temperature because of increased concentrations of carbon dioxide in the atmosphere and other factors. Should temperatures continue to rise, the Antarctic ice sheet would melt and significantly increase the rate of increase in sea level. An accelerated rise in sea level would create problems for low-lying coastal areas. For example, coastal inundation would increase the rate of shoreline erosion, thereby threatening coastal structures and increasing salinity in rivers, bays, and aquifers via flooding and the subsequent rise in water tables. < < go top Objectives The students will be able to do the following: Interpret visual data and graphs. Present a topic in a debate. < < go top Materials Two large glass beakers Two thermometers Masking tape Waterproof markers Aluminum foil Goose neck lamp Graph paper Two meter sticks Stop watch Two trays of ice cubes Instant Ocean® Stainer Four cups gravel < < go top Activity Experiment 1. Place one cup gravel and 1/2 cup of sand in each beaker. Tape a thermometer to the inside of each beaker. Pour salt water (made with Instant Ocean®) into each beaker, leaving 10mm of dry rock above the water. Put vertical tape on beakers; mark water levels both inside and outside. Place four ice cubes in each beaker. Place aluminum foil (dull side up) over one container, sealing the edges. Place a goose neck lamp over the other and follow with aluminum foil. Seal. Have students develop hypotheses on what they believe will occur to the water level and temperature in the beaker. Record temperatures and water levels every 15 minutes until the ice has melted. Record observations on data sheet. Have students graph data. Analyze data and discuss results in terms of the melting of floating ice masses (Arctic analogies). Experiment 2. Fill two beakers with salt water (made with Instant Ocean®). In one, add four ice cubes to the water. To the second, place ice cubes in a strainer above the water level. Again, have students develop hypotheses on the results for each experiment. Mark and record the water level on data sheet. When the ice cubes melt, observe how the water level has or has not changed on graph paper. Analyze and discuss in terms of the different impacts of the melting of floating and grounded ice. < < go top Possible Extension Research information on rises of sea level throughout Earth's history. Graph these sea level changes. Research and debate the different views on the greenhouse effect and/or global warming. Research the effects of increased salinity in rivers, bays, and aquifers. Conduct a salinity test with refractometer or multi-parameter probe. < < go top Teacher Evaluation Check students' data sheets and graphs for accuracy. Have students write conclusions on experiments. Written assessment (sample questions): State your view on either the greenhouse effect or global warming; support your view. Explain why melting of the Arctic ice cap would not affect sea level, while melting of the Antarctic ice cap would affect sea level. Why is the rate or amount of sea level rise not a scientific certainty? < < go top