Mountains as Water Sources - Andes Expedition Part 2
You worry that many of the activities you have seen during the expedition might have an impact on the quality of these water supplies. So far, you've seen land cleared for farming and grazing, trees cut for firewood and charcoal, and plants removed during resource mining. You've even seen the bare land that is left behind. Without vegetation, erosion must be taking place, washing soil into the rivers and degrading the water supply. Are people other than those in the Andes affected by the quality of this water? Are other species affected?
At approximately 11,480 feet (3,500 meters) you notice several long scratches in the rock surface beneath you. Looking around, you realize that this whole section is covered with scratches. They are all facing the same way, parallel to the slope of the mountain. What could have caused these scratches? You try to get some clues from the surrounding landscape. The only thing that strikes you as odd is the random boulders located nearby. How did these boulders get here? Where did they come from? After thinking about it for a little while you are able to figure out that both are the result of glaciers. Glaciers have rocks (sometimes as large as boulders) and debris frozen in them. As they travel down the mountain, these rocks scratch the surface. As the glaciers melt, some of the boulders get left behind. These boulders are called erratics because they are found in odd, unexpected places.
As you continue climbing, you see more and more trash. The side of the mountain is littered with bottles, cans, glass, tent parts, and ropes. Walter explains, somewhat embarrassed, that when the weather gets really bad at high elevations, expedition teams leave everything behind and get down to safety as quickly as possible. Not only does this trash look ugly, but it is yet another threat to mountain water supplies.
At 18,000 feet (5,490 meters) you realize you aren't feeling very well. In fact, you haven't felt well for quite a while. It's difficult to breathe or walk very fast. You haven't been hungry for hours and are starting to feel really nauseous. Your head hurts, too. You felt great yesterday. Could you be coming down with a cold? The flu? Even though you don't want to admit to not feeling well-for fear you might miss out on the final stretch up to the peak-you ask a few teammates how they are feeling. Some are fine, others don't feel well either. What could it be?
Your Expedition Leader thinks it is probably altitude sickness. After all, you have many of the symptoms and have reached an elevation where it is possible. In fact, you are now in the exact location where in 1979 a man spent 66 days studying the effects of high altitude on humans. You think you feel bad today-imagine how you might feel after 66 days!
After resting for quite a while you continue toward the summit. Looking back down the mountain toward the town of Yungay, you notice a deep canyon lake between Huascarán and a neighboring mountain. Lagunas Llanganuco. You wonder how this lake was created. It must have something to do with the glaciers. You know that as snow builds at high elevations it turns to ice. Eventually, gravity pulls this ice down the mountain. On the way down, these glaciers grind away rock and create valleys. Maybe as they move down the mountain, they also carve out basins that fill with snowmelt and precipitation. You remember reading about a glacial lake outburst that took place in the 1940s. Five thousand people were killed in the town of Huaraz when mountain lake surfaces overflowed.
On the way down, you look back toward the peak, and the glaciers look red as they reflect the setting sun. Although they aren't very thick, some of the glaciers on Huascarán are long, stretching as far as a couple of miles. Around the world, glaciers like these are receding because of global warming. Every once in a while when these glaciers break free, people are killed and towns are destroyed down below. You can even see where some glaciers have taken the shortest route, down a steep slope. As dusk falls, you can just barely make out the large boulders these glaciers have dropped in the lower valley.
Suddenly the mountain is very peaceful-the wind has quieted down, the skies are clear, and the stars are out. You've never seen so many stars! Although you wish you didn't have to leave, you are very excited to return to the United States and share everything you have learned about Nevado Huascarán.