Tides

periodic rise and fall due to earths rotation and gravitational effects on moon and sun

tides

difference in height between high and low

tidal range

idealized tidal theory

equilibrium tidal theory

directly proportional

mass and gravitational pull is _________ __________

greatest force - closest to the moon

zenith

weakest force- furthest from the moon

nadir

long vectors = 

short vectors = 

stronger, weaker 

center of mass, Earth travels the path of _____ as orbits the sun

barycenter - underneath Earth 

connects center of mass of an orbiting object to its parent - pulling it inward

revolutions of earth and moon and earth and sun around barycenter 

centripetal force 

excerpted by moon and sun upon earth 

moon > sun

gravitational force 

differences between gravitational and centripetal

resultant force 

resultant force at earths center =

zero

forces from moon are ______ compared to Earths gravity, water is pulled _______ toward _____ and _____

insufficient, horizontally, nadir, zenith

bulge toward and away from the moon - larger of the two

idealized tidal bulge  

points toward sun and away on opposite side

sun bulge 

occurs during new/full moon - greatest tidal range - earth, moon, and sun in syzygy  

spring tide 

occurs during quarter - least tidal range

neap tide 

moon closest to the earth, greatest tidal range - January 

perigee 

moon furthest from E - least tidal range - July

Apogee

spring tide (new/full moon) and closest to the earth

proxigean (evry 1.5 year)

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

declination

time between high tides 

tidal period 

12 hr 25 min

equilibrium theory tidal period 

time between two overhead successive moons

• 24 hr and 50 min 

lunar day

two high tides, two low tides - 6 lunar hours between h/l

idealized tidal prediction 

crest and troughs of tides rotate around ________ points, where there is no tidal range

amphidromic

continents and friction with seafloor

what modifies tidal bulges

one high, one low tide per day

dinurnal

two high, two low per day with a similar tidal range

semidiurnal

two high, two low, with different tidal ranges - most common 

mixed

NOVA SCOTIA

highest tidal range found in

rapidly spinning water between two basins with different tides

whirlpool / meastrom

tide generated wall of water that move up certain rivers

tidal bores