The Sinking CityAva CohenAward: Top 100
School: kentucky country day school In just 75 short years, the city of Venice is predicted to be fully submerged in the lagoon of the Adriatic Sea. When I looked at the photo I took, what first stood out to me was that the stairs off the buildings were completely submerged. I became curious, and discovered the slow descent is caused by a number of factors that can be recognized through physics. The lithosphere of the earth, made of tectonic plates, floats on the fluid, unstable asthenosphere. When water or resources are removed beneath the surface, the crust sinks to maintain balance, known as isostasy. Lying on the boundaries of the African and Eurasian plates, Venice is vulnerable to their movement. Not only does the natural subduction of the plates contribute to its sinking, but over time, human extraction of extensive amounts of water has accelerated the balance of isostasy, causing the crust to sink. Built on small islands formed by sediment buildup, the foundation of Venice does not lie on solid land; it is a mixture of mud, sand, and clay. To stabilize it, wooden poles resistant to rotting were driven into the earth, followed by layers of stone and brick to support the buildings. The weight of the city applies pressure to the ground beneath it, and along with the natural descent of the land, it causes the inevitable sinking of Venice. If no action is taken, the sinking city will be lost beneath the waves permanently. 
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