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Melting Glaciers Cutting Peru Water Supply
NewYorkCountryLawyer writes "In a story that may repeat itself in all mountainous areas dependent on glaciers for their water supply, the glaciers in Peru's Cordillera Blanca mountain range are melting so quickly (PDF) that the water they supply to the arid region is being threatened 20-30 years earlier than expected. Of the time needed for the region to adapt to the coming water shortages, previously thought to be decades, researchers now believe, 'those years don't exist.'"
I don't find this to be a joke. This just emphasizes how little we know about how the earth's systems will react to global warming. My fear is we won't listen to scientists until it is too late and we have killed off the majority of the organisms that help us counter the CO2 we are pumping into the air or the other effects, e.g. ocean acidification.
I'm reminded of the kid who won the Ontario science fair by figuring out how to biodegrade plastic bags. Everyone always told him that it would take thousands of years for bacteria to break down those bags, so he instantly saw that if they break down in thousands of years, something's doing it, and that something can be cultured.
The environment changes, the organisms change. The universe loves organisms, and she'll never stop springing them up in places you'd never think you'd find them.
-1 Uncomfortable Truth
Well, considering that humans didn't arrive in South America until around 15,000 years ago, 40,000 years is out. But more likely most if not all of the area under the glaciers in Peru has never before been seen by human eyes. 15,000 years ago the last glaciation was winding down so the glaciers were probably much bigger than they are now. I doubt those glaciers have ever been significantly smaller since then than they are now.
How can you know what kind of weather occurred in Peru over the last 150 years? Did someone find Mayan engravings? Or there is this very old guy that can swear that this never happened since he was born? Or maybe it was a Union soldier that got lost and decided to start a weather journal?
Ok, I have some homework for you. Go home and read your textbook on Sedimentology, focussing specifically on lake sediments caused by runoff. Read about how the flows of rivers can be read by drilling sediment cores out of lake beds. Then find your textbook on Glaciology, and read about how cores of ice drilled from long term ice deposits can be used to track snowfall. While you are at it, you can read about how rainfall events leave specific signatures in sand and dirt, including rivulets and specific patterns in the distribution of different sizes of sedimentary particles. I suspect snowfall events could also be inferred with similar observations.
You would be amazed at what geologists and geographers can find out simply by using observation and logic.
This and no other is the root from which a tyrant springs; when first he appears as a protector - Plato (423 to 327 BC)
avoid doing something that will cost a lot of money in the short run. And an *enormous* amount of money in the long run.
I'm interested in your source for this. The only reason I'm asking is because of an article I read early this year in one of the Business Review Weekly magazines. The economist was arguing the exact opposite, that the global effort to change the lifestyle and energy sources of half the population of the world would be orders of magnitude more expensive than to simply adapt as a species and relocate or provide resources in some other means to people dispersed by global warming.
Of course this ignores any emotional attachment which people have to their homes, but I can see where he may be making a valid point. For example the system rolled out in Australia is an incredible economic reform and some say it will cost the nation over $1trillion in GDP over the next 38 years. That's a lot of money for a 0.0005% reduction in carbon output in the world.
I think we as a species need to come up with a smarter way of tackling this problem because if the numbers are right we'd basically be bankrupting the world to get humans carbon neutral.
How can you know what kind of weather occurred in Peru over the last 150 years?
The fact that this Peruvian desert had no precipitation left it as one of the few places on earth with sodium nitrate prior to WWI. Europeans imported it for fertilizer and explosives. Germany had to devise a way to synthesize nitrate for their war efforts.
So yes, many people historically were aware of the lack of precipitation in that Peruvian desert and what the recorded precipitation was by the locals due to it being an extremely rare event.
Look at the glaciers as a key reserve of water for the dry season. A glacier in equilibrium will replenish itself during wet season, and act as a source of water during dry season. A melting glacier means it doesn't replenish itself during wet season, and thus a diminishing source during dry season. At some point it means a lost source of water during dry season.