Hypsometer

{
  "id": "MLC-T-MET-006389",
  "term": "Hypsometer",
  "field": "Meteorology and atmospheric science",
  "definition": "An instrument used to measure altitude by determining the boiling point of a liquid, typically water. Since the boiling point of water decreases with decreasing atmospheric pressure, and pressure decreases with increasing altitude, the hypsometer provides an indirect measure of elevation. Early hypsometers were used in surveying and mountaineering before more advanced altimeters became common.",
  "url": "https://mlchart.com/terminology/meteorology/hypsometer/"
}