Thermometers and Anemometers
The youngest students monitor the temperature and wind speed using thermometers and anemometers. They make daily weather reports using both qualitative and quantitative observations. Their observations may include wind speed, windiness, cloudiness, perceived temperature and actual temperature. Students are able to compare their observations with those made by the Environment Canada weather station in their community. Additionally, they can compare their observed monthly average temperature to the archived monthly average temperatures from previous years.
Pyranometers and Sun Photometers
Older students make observations about the atmosphere using a pyranometer and a sun photometer. A pyranometer views the sky from horizon to horizon and measures all of the sunlight (solar radiation) falling on it; in other words, it measures the amount of sunlight a specific location of Earth is receiving. Students use the pyranometer to collect and analyse solar radiation, and then compare their results to those collected by CANDAC scientists and other students. Scientists can use long-term pyranometer measurements to study climate change. Activities, research and investigations will demonstrate that the amount of sunlight reaching the surface of the Earth depends on the region’s latitude, the amount and type of cloud cover, the presence of air pollution and particles in the atmosphere, and the season. Students learn to graph their data to reveal the changes over time.
Another scientific instrument that complements the measurements of a pyranometer is a sun photometer. A sun photometer measures the intensity of direct sunlight over a narrow range of wavelengths. It allows scientists to calculate aerosol optical thickness, thus determining the amount of aerosol contaminants in the atmosphere. Aerosols are important to atmospheric scientists because they can have negative effects on human health and the ozone layer. Interestingly, they can also play a role in mitigating the warming effects of greenhouse gases. Students gather measurements using a sun photometer and then compare their results to CANDAC CIMEL Sunphotometer data and MODIS satellite imagery.
The portable sun photometers and pyranometers we use are available through the Institute for Earth Science Research and Education. As part of the GLOBE project, David Brooks and Forrest Mims designed this inexpensive photometer that uses light emitting diodes (LEDs) as detectors.