The territory of permafrost

The territory of permafrost on Earth is approximately 25 million square kilometers. In this case, the thickness of the permafrost layer varies - on average about a kilometer, but reaches two. Do not be her - battery and moisture custodian - huge spaces North American and Asian continents, where there is little precipitation, would be turned into a desert. In summer the permafrost territory is supported from below by melt water, which is why there is enough, to water the plants of the tundra and taiga. But how can one explain the very existence of kilometer strata of frozen ground?

The territory of permafrost on Earth is approximately 25 million square kilometers

It is known that every 30 m deep into the Earth is increased by temperature on average to 10 C. To raise the temperature by a degree, where the territory of permafrost, you need to go down 300 m! Maybe the heat flow from the incandescent planets here is much less than in other places, or the ability permafrost conduct heat is different from other rocks?

But, the territory of permafrost consists of ordinary rocks, permeated with veins ice. Hence, its thermal conductivity differs little from the thermal conductivity of other rocks. There are no grounds for assuming a reduced heat flux in the vast expanses of Siberia, the Far East, Northern Europe and America.

An interesting hypothesis was put forward by S.M. Grigoriev. The territory of permafrost gives life to its uppermost layer. Salt accumulates here, which are pushed down in autumn, when the layer is frozen from above. Accordingly, the concentration of salts increases here, which, at some point, begin to corrode their base. But the freezing point of the solution is lower than the net water. Therefore, a strong solution covering the top of the permafrost, causes the melting of its thinnest upper layer. As a result, some fresh water is poured into the solution - it becomes less strong. At the same time, the cooler stratum, which desires from above, immediately takes away excess fresh water from the layer of the liquid solution. So gradually the layer of cold solution passes through the entire thickness of the permafrost. Therefore, under the permafrost in a fairly narrow layer, a variety of salts should be concentrated, including, possibly, very valuable.

It is also interesting that along with the film of the solution, heavy water must travel from top to bottom. After all, its freezing point is almost four degrees lower than that of ordinary water.

Heavy water is water, in which instead of the usual hydrogen - deuterium, a heavy isotope of hydrogen. Hence, it is not H2O, but D2O. The chemical properties are the same, the physical properties are almost the same. Heavy water in an insignificant impurity is in ordinary water. But it is very difficult to distinguish it. And it is needed in nuclear reactors - for cooling and for regulation the rate of nuclear reactions.

And this water, perhaps, is concentrated in brines under the permafrost territory.