Final answer:
A seiche is a standing wave in an enclosed or partially enclosed body of water, created by the superposition of two waves moving in opposite directions that alternate between constructive and destructive interference, causing oscillations at fixed locations.
Step-by-step explanation:
A seiche is a standing wave that occurs in an enclosed or partially enclosed body of water. It can be thought of as the sloshing of water back and forth due to its resonance frequency being excited by an outside force, such as changes in atmospheric pressure, strong winds, or seismic activity. Unlike normal waves that travel across a surface, standing waves, including seiches, involve oscillations at fixed locations with crests and troughs that do not seem to move along the surface. This is because a seiche is created by the superposition of two waves moving in opposite directions within the body of water. As these waves reflect off the boundaries of the body of water, they interact with one another, alternating between constructive interference where the waves' amplitudes add together to form a higher wave, and destructive interference where they cancel each other out, resulting in no displacement of the water's surface. While this concept is similar to the oscillation seen in buildings during earthquakes due to resonance, in the scenario of a seiche, it's the body of water that enters into resonance, standing free within its container, and not transferring energy along the surface as traveling waves do.