Looks Still
Pierre-Henri Noundou
Award: Top 100
School: british international school of washington
Teacher: kat deakin
Category: Natural
Photo #21030
Looks Still
This place is so tranquil it can make you feel as if time has stopped. The lake is covered with a sheet of ice and there is hardly any wind but there is still motion occurring on the surface of the water. The air temperature has decreased and therefore thermal energy is being transferred from the lake to the surroundings by conduction and convection. As the water loses internal energy, its temperature approaches the freezing point, and certain regions begin to undergo a phase transition into solid ice. However, these regions freeze at different rates, meaning some areas remain as liquid water until sufficient energy is removed for complete solidification.
Ice can both form and melt around the boundary of the frozen lake. There is still continuous energy transfer throughout the system, even if it is not directly visible. At this interface, latent heat is absorbed or released, allowing melting and freezing to occur simultaneously. The small pieces of floating ice are constantly moving due to fluid currents in the water and external forces such as wind, demonstrating that the system is not in static equilibrium but instead undergoing slow, dynamic change.
In addition to appearing still while being influenced by small external forces, the ice on the surface exists due to density differences within the water. Solid ice has a lower density than liquid water, resulting in an upward buoyant force that keeps it afloat. What looks still may sometimes be in constant motion.
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