• Image of Rowers on River

    Anacostia

    Park District of Columbia

Classroom Activity

Measure Sea Level: Equipment needed, a basin for each group, a ruler for each group, and water in the basin to fill it 1/3 full.

Learning standards: number sense, data analysis: gather, organize, and analyze data, scientific inquiry, identify variables

Time involved: About a half hour

Skills used: Science methodology – multiple measurements and awareness of random chance in science research, tracking data, understanding statistical variability, making observations, estimates, develop a hypothesis and investigate

Explanation for group: Science has to rule out random chance in data. This requires multiple observations particularly on measurements done in the field. We know sea levels are rising. There are now satellites that use different frequency light waves to see through clouds to measure the difference between a fixed orbit the satellite is in and the ocean surface.

But there are swells and waves in the ocean, so how can accuracy be assured? Since sea level rises will impact people and is a likely result of global warming, learning about how measurements are made is important to understanding the impact of global warming. Even with the technology we have only estimates of levels, as absolute accuracy is not likely to occur. The ocean surface is not level but an estimate with enough observations can be trusted to show a trend.

How to: Have students guess ahead of time how many measurements will give a good estimate of sea level height. Have four students to a group and give each group an open container of water. One is the observer who will warn the person doing the measuring if they are not the same height above the container with each try. One is the measurer who will use a ruler to measure the sea level from a fixed distance from the container. (Have the container on a table to make this easier) The third person is going to gently jiggle the container to create troughs and waves. The fourth student keeps track of measurements. Take a minimum of 10 measurements. Take the average of all 10 or more for an average of sea level.

Discussion: Would the task have been easier if the "ocean" were not constantly moving?

How close was the average to the high and low? Would fewer or more observations improve accuracy? Could the person doing the measurement be exact in their measurements or did they have to make quick estimates?

Since an air plane can't lower a ruler to measure distance, what might they use? Consider light in a particular frequency as a tool for measuring distance. Is it consistent? Is it easy to use? Would changing the frequency matter?

Greenhouse Model developed by Stephanie Marrone Equipment needed, Two ice cubes for each student or group, a jar for each student or group and a thermometer that can handle temperatures over 100oF for each and a watch that shows seconds.

Learning standards: number sense, data analysis: gather, organize, and analyze data, scientific inquiry, identify variables

Time involved: About a half hour

Skills used: Science methodology – multiple measurements and awareness of random chance in science research, tracking data, understanding statistical variability, making observations, develop a hypothesis and investigate

Explanation for group:Greenhouse gasses are said to act like glass on a greenhouse. To investigate what this means the group will measure two things. Before you begin have a car handy and the windows open. The car should be parked where students will be working.

Experiment one:

Take two ice cubes placed in the sun. Put a jar over one and track the length of time using the watch that it takes each to melt. Record data

Next : Have half the class lay their thermometers on the hood of the car, the other half of the class lay their thermometers on the dashboard or back if that is in the sun and close the windows of the car. Wait 5 minutes and check the temperatures. Record data

Did the ice under the jar or in the open melt faster? Did the hood or the inside of the car get hot faster? Did the glass act like our atmosphere letting in the sun's heat and trapping it?

Searching for Microclimates Supplies needed: A thermometer, a humidity meter, graph paper for making a map of the school area, graph paper for tracking results, an anemometer is nice but not necessary. A web site below had directions for building one.

http://www.otherpower.com/anemometer.html

Learning standards: number sense, data analysis: gather, organize, and analyze data, scientific inquiry, identify variables

Time involved: 15 -20 minutes without instructional time

Skills used: Science methodology – multiple measurements and awareness of random chance in science research, tracking data, understanding statistical variability, making observations, use of maps and graphs to track data and communicate results, develop a hypothesis and investigate

Explanation: A microclimate is a variance in the regular climate for an area that can be caused by trees, rocks, water, or human structures. Cities have lots of concrete, asphalt, and stone or brick buildings that absorb the sun's heat energy in the day time and release it at night. They also have lots of glass reflecting the sun's energy in some cases, absorbing it into the building in others. Cities also heat and cool structures artificially, releasing heat into the surrounding environment from heat pumps, furnaces, and other equipment. As a result, cities tend to have warmer weather than the open areas surrounding them. They are a microclimate that tends to be warmer than the normal climate for their area.

A simple stone wall may absorb enough heat in the daytime and release it at night to form a microclimate. This warmer microclimate may allow a longer growing season for frost sensitive plants. A rock outcrop may protect plants from the prevailing wind, allowing them to grow more vigorously than those in the steady wind. An increase in humidity might also indicate a microclimate.

How to: On all sides of the school building locate a test spot that can be used through the year. Make a map of the school yard and near-by buildings showing parking lots, side-walks, streets, grass, trees, water, and playgrounds as well as buildings. Locate on the map where you will be measuring weather and north and south.

Each week for the school year, go to each side of the building at different times of day and measure wind speed, temperature, and humidity. Track each of these three on a different sheet of graph paper showing the side of the building as the title, the wind speed, temperature, or humidity on one axis and the time of day on the other. At the end of the year compare different sides of the building. By going at different times of the day you avoid hitting a spot where the sun is always on one side of the building, and another that is always in the shade.

Did one side stay consistently warmer or cooler than the others?

Did one stay consistently more or less humid than the others?

Could land use of surrounding area be a factor?

 

Did You Know?

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