The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). Net downward radiation is the difference between radiation from above (downwelling) and radiation from below (upwelling). Radiative flux is the sum of shortwave and longwave radiative fluxes. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
This concept was harvested from the controlled vocabulary at http://vocab.nerc.ac.uk/collection/P07/current/ on 2022-06-10. Information was pulled as-is for the following properties: dcterms:created, skos:definition, skos:exactMatch, skos:related and skos:notation. The URI of the concept is generated using SHA256 on the CF standard name (in the skos:notation) and concatenated with the TERN controlled vocabularies' base URI (http://linked.data.gov.au/def/tern-cv/).
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