Kirchhoff's law

{
  "id": "MLC-T-MET-006788",
  "term": "Kirchhoff's law",
  "field": "Meteorology and atmospheric science",
  "definition": "A principle of thermal radiation stating that for any material in thermodynamic equilibrium, its emissivity for radiation of a given wavelength is equal to its absorptivity for that same wavelength. This law connects a body's ability to emit thermal energy with its ability to absorb it. The relationship, expressed as emissivity (ε) equals absorptivity (α), is a cornerstone of radiative transfer theory in the atmosphere, applying to gases, aerosols, and surfaces like the Earth.",
  "url": "https://mlchart.com/terminology/meteorology/kirchhoff-s-law/"
}