What are these Gizmos at Izaña Atmospheric Research Center in Spain?
Those are Sun/Moon multispectral photometers and ski radiometers. These are instruments that can scan the sky or track the Sun/Moon for direct measurements. They measure light intensity at multiple narrow wavelength bands, and are designed to measure atmospheric aerosols content and characteristics.

The ones in the third image seem to be a CIMEL CE-138 Sun Sky Lunar Multispectral Photometer (specs).



There is just a few brands that make these instruments. Others are Prede and Kipp &amp; Zonen. I don't know why they have so many at the AEMET. Perhaps it is some sort of instrumentation investigation, where they are testing different types of photometers or different wavelengths. Or perhaps, as these instruments have a filter wheel inside, each one may have a different set of filters to have higher multispectral resolution.