MEA 200 - Waves and Tides

Period

Time passage of 1 wavelength

Frequency

Number of wavelengths that pass a fixed point per unit of time

Longitudinal Energy

Energy moves horizontally

Transverse Energy

Energy moves vertically

Orbital Energy

Energy moves in circular fashion

Perturbing force

Cause of the wave

Restoring force

Returns to still water

Gravity

#1 Restoring force

Capillary waves

Waves smaller than 0.68in.

Gravity waves

Waves larger than 0.68in

Deep-water wave

Water depth is > ½ wavelength

Shallow water waves

Water depth is < 1/20 wavelength

Fetch

How long the wave has travelled

Wind speed, Wind direction, Fetch

Factors affecting wave energy

Swell

Uniform, symmetric waves

Zenith

Point closest to moon

Nadir

Point furthest from moon

Barycenter

Center of mass between moon and earth

Resultant force

Difference between gravitational force and centripetal forces

Perigee

Time when moon is closest to earth

Apogee

Time when moon is furthest from Earth

Proxigean tides

Occurs during overlapping Spring Tide & Perigee

Declination

Angular distance of moon or sun N or S of the equator

Tidal Period

Time between high tides

Diurnal

One high/low tide per day

Semidiurnal

Two high/two low tides per day