PAR; 400–700 nm). Alternative wavelengths are available as an option. Incorporating a custom interference filter with negligible red-leakage, the 305 nm sensor is designed to respond to the region of the UV-B spectrum strongly affected by atmospheric ozone concentration. Similarly, other UV sensors incorporate custom interference filters and sensitive silicon photodiodes to minimize errors associated with spectral leakage.
The GUV-2511 Ground-based Ultraviolet / PAR Radiometer was specifically designed to measure downwelling irradiance at 305, 313, 320, 340, 380, and 395 nm, as well as Photosynthetically Active Radiation (To minimize the effect of changes in ambient temperature, the GUV-2511 features PID-controlled internal heating to maintain the temperature of the optical elements at 40 °C or 50 °C, depending on the deployment site.
The GUV-2511 radiometer is specifically designed to monitor UV radiation in key UV wavebands for biological exposure studies. These wavelengths allow the calculation of the UV Index and the retrieval of cloud optical thickness and total column ozone. The systems are designed to be easily deployed, either individually or in networks, to examine the geographic variability in UV exposure. Components include the GUV-2511, an AC-powered control unit, 50 m cable, and Windows-based LOGGER software.