irradiance.

The amount of radiant power reaching a surface per unit of area.

Use it for

Words that belong together

• solar irradiance
• incident irradiance

On the page

Solar irradiance fell sharply when the dust plume crossed the horizon.

Usage notes

Primary category: sci-fi. Forms: Usually uncountable; no ordinary plural in this sense. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Writing functions: description, setting. Commonness: uncommon.