4

The FAO estimate that we use 11% of the Earth's surface area for agriculture, and that that represents approximately a third of the land that 'could' be used (http://www.fao.org/3/y4252e/y4252e06.htm). If we accept that current agricultural production is at a level that allows the current population to live healthy lives that implies that we could triple ...


3

The assumption is that these contaminants will leach into the ground and reach a source of drinking water. Or they will enter the food chain, by accumulating in plants, eaten by herbivores, eaten by carnivores and/or humans. So the risk is ingestion of material X, with material X being able to affect humans health if its concentration is larger than Y. There ...


2

The same thing that typically cause them,.... Lightning. a very small percentage started by spontaneous combustion of dry fuel such as sawdust and leaves.


2

Before the 1960s, the size of the Aral Sea was relatively consistent. However, the Aral Sea went through some "dry spells" during the 1st and 3rd centuries BCE. Going even further back, the Aral Sea dried up during the Early Pleistocene and was "refilled" during the Early Holocene. In other words, the Aral Sea probably looked the same in ...


2

Where am I wrong in my assumption about natural water distillation (i.e. is rain water not as clean as it should be in theory)? Generally, rain water is pretty clean. That is not an issue. Plus, we treat ground water and reservoir/lake/river water, so we could easily treat rain water. What you really fail to miss is that ground water and reservoir/lake/...


1

Agricultural water is largely Fossil Water, which took tens of thousands of years to accumulate and industrial activities have used it in a century. Saudi Arabia is abandoning programs to grow wheat that achieved self-sufficiency but depleted the desert kingdom's scarce water supplies. Going from the 6th largest exporter to NO more. Humanity derives water ...


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