What's the temperature of the sea?

The annual average surface water temperature of the three oceans is about 17.4℃, of which the Pacific Ocean is the highest, reaching 19. 1℃, followed by the Indian Ocean, reaching 17.0℃, and the Atlantic Ocean is the lowest, reaching 16.9℃. The water temperature generally decreases with the increase of depth. The water temperature is about 4 ~ 5℃ at 1000 meters, 2 ~ 3℃ at 2000 meters and 1 ~ 2℃ at 300 days. The temperature of seawater, which accounts for 75% of the total ocean volume, ranges from 0℃ to 6℃, and the global average ocean temperature is about 3.5℃. Sea water temperature also has periodic and irregular changes such as day, month, year and year. Sea water temperature is often used as a basic index to study the properties of water masses and identify ocean currents. Studying the temporal and spatial distribution and variation of seawater temperature is not only an important content of marine geography, but also of great value to fisheries, navigation, meteorology and underwater acoustics.