Secchi disk

{
  "id": "MLC-T-MET-008732",
  "term": "Secchi disk",
  "field": "Meteorology and atmospheric science",
  "definition": "A simple, flat, circular disk, typically 30 centimeters in diameter, with alternating black and white quadrants, used to measure water transparency or turbidity. It is lowered into the water until it is no longer visible, and the depth at which it disappears is recorded as the Secchi depth. This measurement provides an indication of the amount of suspended particulate matter in the water column.",
  "see_also": [
    "Forel scale"
  ],
  "url": "https://mlchart.com/terminology/meteorology/secchi-disk/"
}