Free nappe

{
  "id": "MLC-T-MET-005755",
  "term": "Free nappe",
  "field": "Meteorology and atmospheric science",
  "definition": "A sheet of fluid, such as air or water, flowing over an obstacle where the underside of the sheet is not in contact with the obstacle and is exposed to the ambient pressure of the surrounding fluid. This condition allows air to circulate freely beneath the flow, preventing the formation of a low-pressure zone that would alter the trajectory and characteristics of the flow. The concept is applied to atmospheric airflow over mountains, where a stable layer of air passes over a ridge without descending immediately into its lee.",
  "url": "https://mlchart.com/terminology/meteorology/free-nappe/"
}