Liquid Earth

Simulated Sea Surface Rising

As I discussed in my previous post, Teaching Tricky Topics, climate change can be a very tricky subject to teach. But rather than shy away from it, I recommend being strategic about it. By focusing only on the strictly scientific principles involved, using hands-on activities students can experience with their own senses, and chunking down the topic into smaller bits, you can still educate your students while (hopefully) avoiding the classroom battle royal.

If you’ve managed to stay with me and have not abandoned ship yet, then I assume you too are determined to teach environmental science accurately. Here is an activity that I wrote with a geologist friend, Elia Gill, that gives students a tangible way to learn about sea level rise due to warming air temperatures. It’s very straight forward, and incorporates math in several ways for my fellow multidisciplinary enthusiasts!

40 minutes total – 10 minutes for setup and initial measurements, 30 minutes for heating/measuring intervals

Materials:

• 4-5 Large to medium clear containers (glass or plastic)
• Three cups of sand per group
• Three cups of room temperature water per group
• 4-5 Large rocks
• 4-5 Metric rulers
• 4-5 Thermometers (in degree C) that can be submerged
• 4-5 Large pieces of ice
• 4-5 Hair dryers
• 4-5 Stopwatches or Timers
• A printed copy of the student worksheet for each student:
• Sea Surface Rising Worksheet

Split students into small groups, with one group per table. Each group will be given a clear container filled with three cups of sand, three cups of water, a large rock, and a large ice cube. They will also be provided a ruler, a thermometer that can be submerged, a hair dryer, a stopwatch or timer, and a worksheet to record their observations and answer questions. This hands-on simulated activity will capture the students’ interest by having them explore the effects of climate change on sea surface levels. The students will model sea surface rising due to glacial melt, a result of the warming of both the atmosphere and ocean water.

Teacher Directions:

• Assemble the sand, and water in the container prior to the activity to allow the sand to settle and the water to clear. These represent the ocean’s floor and water.
• Give each group one prepared container, ruler, thermometer, hair dryer, stopwatch and a worksheet for each student.
• Carefully place the rock so that it sits on top of the sand with the top half of the rock exposed above the water line. This represents land, like continents and islands that people and animals live on.
• Help the students to carefully add the ice cube at the start of the exploration activity. Make sure the top of the rock is still exposed once the ice cube is added. The ice represents glaciers at each of the earth’s poles.

Student Directions:

• At the start of the activity, the students will be asked to place the thermometer into the container in a way that it is easy to read. The thermometer will remain in the container for the full activity.
• They will then be asked to use the ruler to make two measurements in centimeters:
• • Height (level) of water in their container starting from the top of the sand to the water line
  • The amount of rock exposed above the water (from the water line to the top of the rock)
• They are to record their measurements into the table provided on their worksheet (the ‘time’ for these should be marked as ‘0 Minutes’ to indicate that they are the initial measurements before any changes are made).
• Once measurements are taken, they are to draw a picture of their observations on their worksheet and to write down their prediction about what will happen if heat is applied to the container.
• After the initial measurements, observations and predictions are recorded, students will carefully turn on a hair dryer to the medium setting and aim the warm air at the side of the container, roughly 10 centimeters away.
• Using the timer, have the students heat the side of the container for five minutes.
• At the end of the five-minute period, turn off the hair dryer and have the students retake the same measurements as before, filling in the new data into their tables.
• Have them draw a new picture of what they observe now.
• Repeat steps of heating and measurement recording for a total of three more times (at 10 minutes, 15 minutes and 20 minutes, making 5 total cycles including the initial measurements) or until the ice is fully melted. Make sure the data table is fully filled in.
• At the end of the activity, students will be asked to mathematically find the differences between the first initial measurements and the final last measurements, calculating the range of each (how much exactly did each variable change by?).
• After the activity is done, have the students come back together as a whole classroom for the rest of the lesson.

Notes:

• Have the students predict and observe what will/is happening to the temperature and level of the water throughout the demonstration activity.
• Be careful to say climate or global change, not only global/climate warming. This is to reinforce the concept that the overall global climate is changing in many ways, not only by warming temperatures. The activity looks at warming temperatures as one change out of several.

Probing Questions:

1. What happens when we blow hot air at the container?
2. What happened when the ice melted?
3. Was your first prediction supported? Or not supported?
4. By how much did the water level/temperature rise? What was the range of change?