That's right. After decades of being asked to save the whales and the tigers, and more, you are now being called upon to save glaciers and underground bodies of water. It has longed been theorized that the ability to store food was the ultimate lynch pin of human civilization. However, one of the ecology movement's most important insights is that food is water (often lots of it). And so far, our methods of storing and transporting are very limited in scale, and very expensive in terms of money, infrastructure, energy, and losses to evaporation. If you look at the distribution of freshwater on earth, a very high percentage of it however is "stored" either underground or in the form of ice.
Of course, glaciers have largely been looked upon either the visually beautifully casualties of global warming, or as synonymous with the purest water on earth. Of course, the consumers in supermarkets who buy "glacier pure" bottled water have most likely never been too close to an actual glacier. Real glaciers are often full of debris, dirt, pebbles, dead animals, and even pollution from far away. But what many people don't know is that glaciers are to a large extent nature's "water towers" with the snowmelt feeding many of the world's rivers. Some parts of the world such as India and parts of the United States are heavily dependent on ice melt for both human uses and the ecosystems. Restoring the glaciers may sound right out of science fiction, but artificial glaciers have in fact been used as "appropriate technology" in India. And if done on large scales they might not just serve as a water saving tactic, but might help slow down climate change. Basically the ice on the planet reflects sunlight, while rocks especially the ones with dark colors, tend to store heat from the sunlight. Physicists refer to this property as "albedo" or the propensity of materials to reflect light rays rather than absorb them-mostly as heat. And it can be a major factor in the temperature of a planet. So if ice caps and glaciers melt on earth, the planets albedo could drop and global warming would accelerate. And similarly more ice could cool the planet. This is the reason some people have suggested painting roofs or even rocks white, white topping streets and so on as either a way to cool cities, or even the planet itself. However, it is unlike that such technology could be a magic bullet if greenhouse gases are not addressed more directly.
Also groundwater has been found to be more than just a series of passive vessels that take in rainwater until it is removed. For example scientists have discovered that having a lower water table over a certain land area can influence the length and severity of droughts, even if they do not cause them per se. In the past it was taken for granted that depleting groundwater wasn't an ecological problem per se, because it didn't degrade the ecosystem but simply meant that the resource was no longer available. Now we know that reality is a lot more complicated. Also more recent studies shown that some methods of "water conservation" such as lining canals with concrete can decrease the amount of water penetrating the ground table. As can the placing of concrete and asphalt over many land surfaces, and in some cases the losses of certain animals such as prarie dogs. Another controversial measure to increase the amount
of water underground is the concept of injecting highly purified sewage into the water-table. Somehow this idea generates more opprobrium than the amount of uncleaned sewage that gets into the groundwater table regularly, or the number of poorly maintained septic tanks all over America. Is the idea of recycled sewage the next thing people will have to "get over" for the sake of survival? Very likely.But more important is the idea that groundwater far from being an inert underground mass, is in fact, deeply connected with other aspects of the local ecology, including the above ground flora and fauna, the soil conditions, and even the land/atmosphere interactions.
Say Goodnight Readers!
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