Do Earth's oceans gain or lose water, considering evaporation and precipitation together? How much?

Question

Maya Adams · Accepted Answer

Besides almost balancing evaporation and precipitation, there is input of water to seas from external sources, above mean-sea-level. So, there ought to be gain over centuries.

External sources above mean-sea-level (MSL) contribute water to seas. This includes water from arctic sea-ice and antarctic. continental-ice. Rise in sea level over a long period of centuries, and consequent loss of coastal land that is taken into the sea, provide evidence for gain of water in the seas.

Aaron Anderson · Answer

undefined Earth's oceans experience a net gain of water when considering evaporation and precipitation together. This phenomenon is part of the global water cycle, where water evaporates from the surface of the oceans due to solar energy and then condenses to form clouds, leading to precipitation. The amount of water gained by the oceans through precipitation exceeds the amount lost through evaporation. On average, the Earth's oceans gain about 385,000 cubic kilometers (km³) of water annually through precipitation, while losing about 348,000 km³ through evaporation, resulting in a net gain of approximately 37,000 km³ of water each year.