Evanescent level

{
  "id": "MLC-T-MET-005488",
  "term": "Evanescent level",
  "field": "Meteorology and atmospheric science",
  "definition": "A theoretical level in the atmosphere where vertically propagating waves, such as gravity waves, transition from propagating to decaying exponentially with height. This occurs when the wave's frequency is below a certain cutoff frequency, often related to the Brunt-Väisälä frequency. Waves at this level do not transport energy vertically but can transfer momentum.",
  "url": "https://mlchart.com/terminology/meteorology/evanescent-level/"
}