A Mountain of Water
Posted by hyperpat on February 7, 2007
The idea of using icebergs as a fresh water source has been floated around quite a few times, and is gaining headway again in view of the concerns over what will happen to the climate in certain areas that are already short on clean water given the projected warming trend over the next fifty years. Does the idea really make sense?
First off, there is certainly a large enough supply of naturally occuring icebergs to fufill any expected need from this source for quite a long time. Unless the world’s glaciers and ice caps totally melt, it will continue to be there. And as it sits right now, icebergs represent both a hazard to shipping and a natural resource that is not being utilized. If these bergs were used to supply fresh water for land use, it obviously would reduce the amount of fresh water being added to the world’s oceans, but only temporarily, as after use such water would eventually find it’s way back to the oceans.
Second is the energy and economic cost of pushing these bergs to where we want them, and setting up appropriate facilities to pump the melt water into the local water system. While this is not a small item, and in fact is one of the major reasons why it hasn’t really been tried yet, neither is outside the pale of what is doable with the right economic incentives. And this is where the real crux of the matter shows up: in most of the world, the cost of water is very low, and the cost of getting water from an iceberg is much higher than this. However, in those areas with chronic water shortages, many of which are the same areas projected to get even less rainfall under the effects of global warming, it might make sense to pay such a high price for water (versus not having any at all). Areas where there is a water shortage can become flash points for conflicts and wars (it’s certainly happened in the past) – and the economic cost of wars (not to mention the humanitarian cost) is much higher than what would be needed to do something like this. Other technical problems, like the need to wrap these bergs in a huge plastic baggie to prevent the sea water from mixing with the pure melt runoff, have already pretty much been solved.
So it doesn’t appear as if there is any real roadblock to doing this. The only real problem is getting either a government or a large enough corporation to take the first step and provide enough funding to really try it, and so far these entities have been more enamored of desalinization as a solution to the water problem. An even further out solution has been proposed, that of moving a icy asteroid into near-Earth orbit and mining it for water – but this idea is clearly a lot further away from becoming a reality. But sometime soon, we better come up with some solution, as clearly our usage is outstripping the supply.