Using our new PAR (Photosynthetically Active Radiation) Sensor, we have developed an investigation to model the angle of insolation and its impact on plant distribution and growing seasons across the globe. A halogen light bulb and globe are used to represent the sun and Earth while the Vernier PAR Sensor is placed on different latitudes to determine the amount of light available for photosynthesis at these locations. As the student changes the angle of the sun with respect to Earth to represent each season, the PAR value changes at each latitude measured.

Download student and teacher instructions for Modeling the Sun’s Influence on Growing Seasons »