Seasons and Angle of Insolation

Introduction

Have you ever wondered why temperatures are cooler in the winter and warmer in the summer? This happens because the Earth’s axis is tilted. The Earth remains tilted as it revolves around the sun. Because of this tilt, different locations on the Earth receive different amounts of solar radiation at different times of the year. The amount of solar radiation received by the Earth or another planet is called insolation. The angle of insolation is the angle at which the sun’s rays strike a particular location on Earth. When the north end of the Earth’s axis points toward the sun, the Northern Hemisphere experiences summer. At the same time, the south end of the axis points away from the sun and the Southern Hemisphere experiences winter.

In this experiment you will investigate the relationship between angle of insolation and temperature change due to energy absorption from a simulated sun—a light bulb.

Objectives

In this experiment, you will

• Use a Temperature Probe to monitor simulated warming of your city by the sun in the winter.
• Use a Temperature Probe monitor simulated warming of your city by the sun in the summer.
• Measure the angle of insolation.
• Determine the relationship between temperature change and angle of insolation.