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A stable bi-product, water, water, everywhere.

 

In another chapter I suggested that all the water on Earth has been produced as a waste product by trillions of methanogens, an ancient form of life, over a 3.5 billion year period. This water synthesis is still ongoing and is attributable to the annual increase in sea-level. It has been noted from tide gauges that sea levels have increased by 18 cm over the past 100 years (Warrick and Oerlemans ). Many other indicators show that this sea-level increase has been consistent since the times of the earliest civilisations. We can extrapolate further into geological time, if we consider that the production of water is, like it’s producer, increasing exponentially over time.

 

It is estimated that there are 1.2 trillion, trillion litres of water in the oceans (Wikipedia). If we place this figure at the top of the curve on an exponential graph, we can extrapolate for quantities of water which may have existed at different stages up to 500 million years ago. We can also see how this sits with the amount calculated from ocean level increase over the past 30 million years. We must also allow for the increase in ocean-bed area as the Earth’s radius gets larger over time and we can take this information from my small Earth models.

 

By dividing the total quantity of water at a given time by the surface area of the Earth, at the same time, we can gather some idea of the depth of water, if the water were to cover the whole surface, and if that surface were the same level throughout.

 

These are only crude figures and the amount of glaciation is not included in the calculations. However, glaciation has less significance in the equation than one may consider at first. This is because glaciation is cyclical; water vapour from the oceans freezes on high ground at the cooler polar regions. A mass of ice accumulates which gradually moves down to lower ground and eventually to the ocean where it melts back into sea water. Ice which forms over sea water (pack ice) merely displaces the water and when it melts (such as during a post major glacial) the water level is not altered. Greenland, for example, is an archipelago of high mountainous terrain and many of its glaciers already exist over water.   

 

Similarly, there is a cycle for water on land; water vaporises from the oceans’ surface, forms rain clouds which deposit water on land, and this water gravitates into aquifers and rivers and eventually returns to the oceans.

 

Water accumulation calculated from graph

 

 

 

 

 

 

 

 

 

 

 

 

THE ACCUMULATION
OF WATER