出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/06/25 16:29 UTC 版)
The bathythermograph, or BT, is a small torpedo-shaped device that holds a temperature sensor and a transducer to detect changes in water temperature versus depth. Lowered into the water from an underway ship, the BT records pressure and temperature changes as it is dropped through the water. Because the pressure is a function of depth (see Pascal's law), temperature measurements can be correlated with the depth at which they are recorded. The bathythermograph was first developed by Athelstan Spilhaus in 1938.