International Hydrological Decade

Mayo L. R., Meir M. F., and Tangbom W. V. (1972) A system to combine stratigraphic and annual mass-balance systems a contribution to the International Hydrological Decade. J. Glacial. 61, 3-14. 

According to the locality, surface waters are categorized into continental and sea waters. Based on the measurements within the framework of the International Hydrological Decade (1965-1975) the world oceans contains 1228 million km of water which represents about 96.5% of all water reserves of the Earth. Not quite 3% of the reserves on the Earth is common continental water. The volume of continents emerging above the sea surface is about 125 million km. The ratio between the volume of continents above the sea to the volume of the seas is approximately 1 11. 

The supply of naturally occurring fresh water available for human use is limited. It consists of nonrenewable sources such as aquifers and other reservoirs that are not recharged as they are used, and renewable sources such as lakes, rivers, reservoirs and other sources that are replenished by the annual water, or hydrologic, cycle. However, the amount of water available in a given location as a result of the natural water cycle is essentially fixed. Thus as the population increases, the annual water supply per person, which is a general indicator of water security, decreases. The per capita water supplies worldwide are approximately one third less now than in 1970 due to population growth since that time. The water supply crises which already exist and are projected over the next few decades have received much attention recently. Population Action International expressed the concern quite... 

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