Spherical pyrgeometer

{
  "id": "MLC-T-MET-009133",
  "term": "Spherical pyrgeometer",
  "field": "Meteorology and atmospheric science",
  "definition": "An instrument that measures longwave (terrestrial infrared) radiation arriving from all directions, the full 4 pi steradians, on a spherical receiving surface, so it responds to both the sky and the ground around it. It differs from an ordinary pyrgeometer, whose flat receiver sees only one hemisphere, and from the spherical pyrradiometer, which responds to shortwave as well as longwave radiation.",
  "url": "https://mlchart.com/terminology/meteorology/spherical-pyrgeometer/"
}