Hydrosphere 
The hydrosphere includes all the liquid water on or just below the surface of the planet, the vast majority of which is in the oceans. Some of Earth’s water is frozen, mainly in Antarctica and Greenland. This ice and snow is called the cryosphere and is often included with the hydrosphere when accounting for the distribution of Earth’s water (as is done in this article). About 71 percent of Earth’s surface is covered by water.
From: https://kids.britannica.com/students/article/Earth/274103/273809-toc