Purgatory 1701

The city I am rooted to is Minneapolis, my home for 18 years now. I don’t want to write generalizations about buildings and people for this blog, I feel that the land has much more power than buildings and people could ever possess. Cities are so manufactured, so manmade that it is easy to forget about the power the land has over them. In Minneapolis, the power the land has is subtle. There are no crashing oceans, or towering mountains. But the land here is strong; Minnesota is home to 11,842 lakes and the second oldest rocks on Earth. This city’s energy comes from its stone and water.

The most prominent geological features of this city are its LAKES. What power do they have? They do not cycle like the sea or flow like the river. They seem quiet and calm. That perception of quietness is the wooliness of the lake, not the essence. The water in lakes is flowing and cycling, and this flow has the power of both life and death.

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Lake turnover.

Water has a curious property. Unlike other compounds, solid water is less dense than its liquid form. Ice can float on water. In addition, cold liquid water is denser than warm liquid water. This property of water makes it one of two known compounds in the universe capable of supporting LIFE. Without water of Earth, there would be no life at all. The lakes can show us why: These phenomenon create the lake turnover effect.

As Autumn comes, the air cools the top of the lakes, that water becomes denser and sinks. The water at the bottom of the lakes is forced upwards, where it cools as well. This mixing allows the water to become oxygenated. Without it, the bottom of lakes would become stagnant and dead. Winter comes. The water at the top of the lake becomes so cold that it freezes, this protects the rest of the lake from freezing. Ice floats, so there is a pocket of liquid water under the ice which allows life to continue below the surface. When spring arrives, the ice melts creating cold water at the top of the lake once again, and once again this water sinks, mixing the lake. The lake fosters life.

People are drawn to the lakes. In good weather the lakes are the busiest places in the city. People, too, flow around them and in them.

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Lakes can hold the power of death as well. Regular lake turnover only happens in places that have cold winters. In 1986 Lake Nyos of Cameroon killed 1700 people. This lake lies above a volcanic fault. The magma leaks CO2 into the lowest waters of the lake. There is no turnover because the climate is so warm, so the gas saturates the water. The lake stayed like this for years, slowly building up gas, until finally on August 21 a landslide triggered a massive turnover releasing a huge cloud of CO2 into the lake basin, the cloud of gas spilled into a nearby valley displacing all the other gasses. It suffocated all life along the valley for 20km.