Finding WATER in a DESERT.


Water is the most interesting naturally abundant substance on Earth, it is the medium of life, and it is scarce, especially in the desert. One of the most important reasons the Dry Valleys need to be protected is because the ecosystem here is so simplified. Unlike the forests and groves of the Portland valleys this area has little influx of nutrients from rain, rivers, or animals. Furthermore, it also has limited macro organisms to disrupt the balance of the microbial life in the lakes.



"A lake is the landscape's most beautiful and expressive feature. It is Earth's eye; looking into which the beholder measures the depth of his own nature."


-Henry David Thoreau-



First the Facts:


Ninety-seven percent of the water on the planet is in the form of salt water. Only 3 percent is fresh, and two-thirds of that is ice.


Water molecules are made of one oxygen and two hydrogen's bonded together.


Water is a POLAR molecule so each side bears a slight charge, the Oxygen side is partially negative and the Hydrogen side is partially positive.


Water is relatively incompressible.



Water has a very high surface tension which allows you to fill a glass up above the rim without spilling anything on the floor (make sure to be very careful!!!).


When cooled to its freezing temperature (0°C, 32°F, under standard pressure), water changes to a colorless, crystalline solid (ice).


Water is one of the only liquids on earth that expands during freezing and is therefore less dense in its solid form (ice) than as a liquid at 4°C.


Water is the universal solvent (which means it is the best liquid to dissolve particles in).



The United States uses three times as much water a day as the average European country, and many, many times more water than most developing nations.





The main fact is that WATER is LIFE.

Here in Antarctica our research takes place where the life is—beneath the ice. Remember that when ice forms it incorporates only pure water into its crystalline matrix. The molecules that remain are in the water and the concentration of these compounds changes based on depth (this is because temperature and ambient light also changes with depth). So water beneath ice has an extremely different composition from other water. The water beneath the ice holds trapped dissolved CO2 (not commonly found dissolved in lakes), dissolved O2 (present in other lakes, remember seeing small bubbles in the water?), and is very saline (salty), all of the compounds work together to give life to the extremophiles that habitat the water columns.


The BIGGER picture:

The Lakes of the Dry Valleys are treated scientifically like a baseline of research. When they are understood it is possible to further understand the more complex ecosystems of this world. More importantly due to the fragile state of this ecosystem the effects of global climate change or climate warming are drastically expressed by the lakes. When lake ice thickness diminishes it changes the amount of ambient sunlight that reaches the lower depths of water. Slight increases in temperature or increases in the amount of light can both have drastic effects on the microorganisms of the lakes. Changes like these can influence metabolism, temperature regulation, reproduction, and evolution. All of these things together lead scientists to believe that the changes in the lakes of the Dry Valleys are a good representation of the changes that could occur in our world if global warming continues.












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