surface_downwelling_photon_flux_per_unit_wavelength_in_sea_water
The surface called "surface" means the lower boundary of the atmosphere. Downwelling radiation is radiation from above. It does not mean "net downward". The sign convention is that "upwelling" is positive upwards and "downwelling" is positive downwards. A photon flux is specified in terms of numbers of photons expressed in moles. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. A coordinate variable for radiation wavelength should be given the standard name radiation_wavelength.Aliases for this term
surface_downwelling_spectral_photon_flux_in_sea_water
The surface called "surface" means the lower boundary of the atmosphere. "Water" means water in all phases, including frozen i.e. ice and snow. Downwelling radiation is radiation from above. It does not mean "net downward". A photon flux is specified in terms of numbers of photons expressed in moles. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.This term is not aliased.