Task: Class Definition Understanding (ontology: Earth_Environment/OBOE)

Which of the following definitions best describes 'Radiance'?

A. The developmental stage of life of a given organism.
B. The number of photons striking an area per unit time. This could be probably also be called a PhotonArealDensityRate.
C. the concept amount of substance of solute B in a solution divided by the mass of the solvent: Often favored because measurements of mass are more precise than measurements of volume.
D. the concept and spectral the concept are radiometric measures that describe the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle in a specified direction. They are used to characterize both emission from diffuse sources and reflection from diffuse surfaces. The SI unit of the concept is watts per steradian per square metre (W·sr−1·m−2).

Answer: the concept and spectral the concept are radiometric measures that describe the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle in a specified direction. They are used to characterize both emission from diffuse sources and reflection from diffuse surfaces. The SI unit of the concept is watts per steradian per square metre (W·sr−1·m−2).