All the water in the world (1.4b km3) and all the air in the atmosphere (5140 * 10e18 kg) gathered into a ball at sea-level density. Shown on the same scale as the Earth.

2008-10-30:

An “atlas of hidden water” has been created to reveal where the world’s freshwater aquifers really lie. “The hope is that it will help pave the way to an international law to govern how water is shared around the world.”

Useful to predict the wars of the future.
2013-12-07:

The volume of this water resource is 100x greater than the amount we’ve extracted from the Earth’s subsurface in the past century

2020-11-24:

The mantle transition zone (MTZ) at a depth of 410 to 660 km is considered to be a potential water reservoir because its dominant minerals, wadsleyite and ringwoodite, can contain large amounts of water up to 3 weight %. To fit the observed mantle viscosity profiles, ringwoodite in the MTZ should contain 1 to 2 wt % water. The MTZ should thus be nearly water-saturated globally.

The MTZ is estimated to hold 3x the amount of water as the world’s oceans. This makes books like Flood more plausible. earlier estimates thought it was more like 2x:

Evidence suggests the middle of Earth’s mantle holds as much water as the planet’s oceans. If scientists can prove without doubt that the middle mantle is filled with water, it calls into question theories that suggest water arrived on Earth from comets.

See also 2.8t Tons of Fresh Water Under the Ocean

Low-salinity submarine groundwater contained within continental shelves is a global phenomenon. While low-salinity groundwater is thought to be abundant, its distribution and volume worldwide is poorly understood due to the limited number of observations. The data suggest a continuous submarine aquifer system spans at least 350 km of the US Atlantic coast and contains 2.8t tons of low-salinity groundwater.