I'm studing the correlations between solar radiation (global, direct and diffuse) and UV solar radiation.
There are also direct and diffuse measurements of UV
using sun pointing systems for spectral or specific wavelength (filter) instruments, or shaded broadband UV meters.
For Vienna we have a long tme series of about 15 years for global and diffuse UV radiation, measured with the solar light sensors. These data are available on requwat.
Hello Germán,
I think this is because the scattering of UV is so high that there is no point in distinguishing between the direct and the diffuse portion.
I dont think that only UV rays are considered. Global measure will include UV NIR and VIS all. (direct + diffused). yes, we can measure them seperate as UV global, UV direct using some filters
Hello Sandeep: Thank you very much for your answer.
My question is directed towards the broadband type sensors.
Just a small addition: some broadband sensors may have a 2PI (semi-spherical) or 4PI (spherical) collector, and others may have a planar (cosine) collector. The cosine response may vary from one instrument to another because, in the end, they are weighting differently photons from different directions. And the angular distribution of UV photons may vary strongly depending on olar zenith angle, cloudiness, etc.
There are instruments that measure narrow band spectral v
Irradiance in the the UV. They measure global, diffuse and calculate direct normal for these wavelengths.
This may surely depend on the type of study or the purpose of data collection.