the depth at which a Secchi disk is no longer visible from the surface of ocean water.
A measure of the clarity of water, especially seawater. Secchi depth is measured using a circular plate, known as a Secchi disk, which is lowered into the water until it is no longer visible. High Secchi depths indicate clear water; whereas low Secchi depths indicate cloudy or turbid water. See also Secchi disk.
noun 1. an opaque, white or black-and-white disk used to measure the cloudiness or turbidity of ocean water by the point at which it is no longer visible from the surface. Secchi disk An instrument used for measuring the clarity of water, especially seawater. It consists of a circular plate divided into alternating black and […]
noun 1. fresco secco. adjective 2. (of notes or passages in a musical score) played and released abruptly and without resonance. noun (pl) -cos 1. wall painting done on dried plaster with tempera or pigments ground in limewater Compare fresco 2. any wall painting other than true fresco
- Season creep
noun 1. the gradual changing in the length of the seasons, as demonstrated by earlier flowering of plants, etc, thought by many to be caused by climate change
- Seasonal unemployment
seasonal unemployment definition Periodic unemployment created by seasonal variations in particular industries, especially industries such as construction that are affected by the weather.