Glaciers And Nutrients

There is a long-term implication of global warming that has occured to me. The last ice age ended 12,000 years ago and we rarely stop to think about how important those ancient glaciers actually are to life as we know it.

We know that there has been more than twenty ice ages. Normally, about 10% of the earth's surface is covered by ice but during the ice ages, this increases to about 30%. The vast majority of the earth's land is in the northern hemisphere and this is where most glaciation takes place.

It is very clear that the most fertile land on earth is that which was covered by ice during the ice ages. Glaciers are sheets of moving ice about 1-2 kilometers in height and they slide along the underlying rock strata, particularly at the ends of the ice ages when the glaciers begin to melt and break apart. The important thing here is that the moving glaciers stir up nutrients that are vital to life from deep underground.

The so-called "Fertile Crescent" in the Middle East that was the site of so many early civilizations was fertile for a very obvious reason, it was the path of glacial bergs that slid down from the mountains to the north and east. Part of the Fertile Crescent became the routes of the Tigris and Euphrates Rivers.

In a similar way, the most fertile areas of Europe is the plain across the north of the continent and the East Anglia region of Britain. These areas were also well-plowed by the glaciers as were the most fertile areas of North America.

In contrast, tropical soils that never get plowed in such a way by glaciers are easily depleted. This is true even with the heavy rainfall that they may receive. Lack of glacial plowing is the trouble with much of the soil in Australia.

There is a story from ancient times about a dying farmer who wanted his sons to escape from poverty. He told his sons that there was treasure buried in his fields and if they wished to be rich, they could dig for it. The sons dug up all of the fields to a depth that no plow (plough) had ever reached. Yet, they found no buried treasure and put the project aside when it came time for planting.

The harvest that year was bountiful such as they had never seen before and from that and successive harvests, the sons gained considerable wealth. The father's plan had worked. By digging the soil to great depths, vital nutrients were stirred up that would otherwise had been lost and the result was much better harvests.

The fact is that nutrients which are vital to life are continuously lost by sinking deep into the ground unless the soil is periodically plowed up by glaciers. This is similar in concept to "The Bone To Flesh Ratio" on this blog. This explains why, from the age of the dinosaurs, creatures on land must get smaller in size because bone material disappears from circulation in the biosphere faster than flesh material.

This can only mean that if we warm the earth enough to stop the ice ages, there will be no glaciers to stir up the nutrients deep in the soil and in the distant future, enough nutrients will be lost to bring to a halt most life on land.