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Radiation measurement on frozen lake
A student begins to measure radiation (light) on frozen Bear Lake, Utah-Idaho. The spherical probe will be lowered through the water column, and light intensities recorded at 1-2 m (3-6 ft) intervals. The data will be used to estimate if there is sufficient light for photosynthesis, and for fish predation. Light measurement under the ice are difficult, because drilling a hole and disturbing the surrounding snow cover allows more light to enter the lake.