Effect of the Sun's Energy on the Ocean and Atmosphere

By Mitch Fox, Ron Miller, and Seema Gupta

Radiative Balance

The energy balance of the solar energy reaching earth must be studied to verify that the amount of energy coming in equals the amount being radiated out. This is called radiative balance and conforms to the Law of Conservation of Energy. To validate this theory, several satellites have been launched into Earth's orbit that indirectly measure the energy absorbed and radiated by the earth and by inference the energy stored. The NASA Earth Radiation Budget Experiment (ERBE) project involves three such satellites: the Earth Radiation Budget Satellite (ERBS), launched October 1984; NOAA-9, launched December 1984; and NOAA-10, launched September 1986.

Earth Radiation Budget Satellite (ERBS), launched from Space Shuttle Challenger, October 1984. Photo: ERBE, Atmospheric Sciences Division, NASA LaRC.

Team Mission

The Oceans research project at the GISS Institute on Climate and Planets is organizing a team of researchers to study radiative balance. As a member of this research team, your mission is to conduct a series of tasks that enable you to audit Earth's radiative budget and help answer a number of science questions. If you are an educator, you might want to read the note to the teacher from the authors.

If You Accept This Mission ...

You will analyze the measurements by keeping a balance of incoming and outgoing solar radiation. Your balance will be like an energy bank account for the earth. For a specific region, you will calculate the local budget to determine if the earth is really in radiative balance. This could help shed light on the question of global warming if for example we found that more solar energy is being absorbed by the earth than emitted to space. It could also help to improve climate modeling through a better understanding of the role of the earth's regions in the energy budget.

Science Questions

You will have a number of tasks to perform. Keep the following science questions in mind while you conduct the tasks. At the conclusion, you should be able to understand and answer these science questions that guide this research project.

Note: You are not expected to answer these questions now. You will answer them after completing all the tasks.

1. Does the region you have studied absorb more energy than it emits? Defend your answer with the results of your calculations.
2. Describe how the solar energy flux absorbed at the particular location you are studying varies over the course of the year?
3. How does the solar energy flux absorbed by the tropics vary over the course of a year? How does this compare to the change at the polar latitudes?
4. At the equator, how does the total absorbed energy flux for the year compare to the total emitted? At the polar regions, how does the total energy flux absorbed for the year compare to the total emitted?
5. What must be happening in terms of energy flow between the tropics and the poles to maintain total radiative balance of the planet?
6. What dynamic processes can maintain the temperature of the tropics despite a net energy input?

In order to get started you will need some background information on the project. Use the diagram below to navigate. So, away we go ...

Mitch Fox is a teacher at the Bronx High School of Science. Seema Gupta was a student at the Bronx High School of Science at the time this module was written. The scientist advisor on project was Ron Miller. (August 1997).