Pat Neale
SR-18 UV Monitor
The SR-18 UV monitor was invented at the Smithsonian Environmental Research Center (SERC). A disk with 18 different filters rotates 15 times every minute. The filters select different UV wavelengths, which are passed to a sensor and recording computer. The sensor is kept dry and at a constant temperature to get a stable response. Smithsonian Institution scientists pioneered atmospheric monitoring in the late 1800s.
- In the woods, an SR-18 records that even leafless trees block about half the usual UV radiation.
- Photo Chip Clark © Smithsonian Institution
- Pat Neale uses the SR-18 UV monitor to measure ultraviolet light reaching Earth’s surface.
- Photo Chip Clark © Smithsonian Institution
- The SR-18 is one of several meteorological instruments perched on a tower at SERC to get a clear view of the sky. Cables feed data from the instruments to computers in the small shed at the base.
- Click here to see how much UV is at SERC
right now. - Photo Chip Clark © Smithsonian Institution
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