Clear-air echo

{
  "id": "MLC-T-MET-004333",
  "term": "Clear-air echo",
  "field": "Meteorology and atmospheric science",
  "definition": "A radar return signal detected from atmospheric regions that appear visually clear, without visible clouds or precipitation. These echoes are caused by variations in the refractive index of the air, often due to small-scale fluctuations in temperature and humidity. Clear-air echoes are used to study atmospheric boundary layer dynamics and detect clear-air turbulence.",
  "see_also": [
    "angel"
  ],
  "url": "https://mlchart.com/terminology/meteorology/clear-air-echo/"
}