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Capabilities / Instruments

CIMEL Sun Photometer in Action

CSPHOT

Sunphotometer

Baseline Instrument, External Instrument, Guest

The Cimel sunphotometer (CSPHOT) is a multi-channel, automatic sun-and-sky scanning radiometer that measures the direct solar irradiance and sky radiance at the Earth’s surface. It takes measurements at predetermined discrete wavelengths in the visible and near-infrared parts of the spectrum to determine atmospheric transmission and scattering properties. The CSPHOT only operates during daylight (sun above horizon).

Primary Measurements

Handbook Browse Data

Contact

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Lynn Ma
Lead Mentor Brookhaven National Laboratory

Related Data Announcements

Aerosol Optical Depth Best Estimate Production Data Available for 2 ARM Sites

References

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Russell et al. EPCAPE Field Campaign Report. 2025.

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Atmospheric Radiation Measurement (ARM) | Reviewed March 2025