Hydrosphere Contents

1. Water

Most of the world's water is found in the oceans

By far the largest fraction of the Earth's water is stored as seawater in the oceans (97.3%) or as buried seawater in marine sediments. Most freshwater is present as ice in the ice caps and glaciers with much of the remainder being present in groundwater, both deep and shallow. Less than 0.02% of the total hydrosphere (and less than 0.5% of the world’s total freshwater) is present on the continents, as lakes and rivers. The amount of freshwater in the atmosphere is very small compared with the other reservoirs, equivalent to only 0.001% of the total. However, these waters play a very important role in the global cycles of many chemical species.

One estimate of global water distribution:

One estimate for global water distribution.

Where is the majority of the water in the hydrosphere stored?