Tides The ____________ short term changes in the ___________ (rise or fall) of the ocean surface at a particular place

Tides Caused by a combination of __________ between the __________, __________ and __________ __________ force of the _________ and the _________ Moon’s influence 2x’s the sun’s (it is closer to Earth) the motion of __________

Tides The __________ of all __________ Wavelength = ½ Earth’s __________ They are always in __________ water They are the __________ _________ is proportional to __________ Tides move quickly ~1600 kilometers per hour (1000 mph)

Tides Also affected by: 1. ______ and ______ of the ocean floor 2. __________ (greater pull at equator) 3. __________ of water

What Causes Tides? Tides are caused by the ____________________of Earth, the Moon, and the __________. _____________is the reason for tides. Gravity is the ____________ exerted by an object that ____________other objects toward it.

Moon’s Gravity and Tides The Moon’s __________affects the __________on Earth’s surface. Since the Moon is __________to the Earth, it has a __________gravitational pull on it (closer objects have stronger gravitational pull).

Moon’s Gravity – Tidal Bulges The Moon pulls on the water on the side __________to it more __________than it pulls on the __________of the Earth. This __________creates a bulge of water, called a _____ __________, on the side of Earth __________ the the Moon.

Moon’s Gravity – Tidal Bulges The water on the side of Earth facing __________from the Moon has a __________strong pull. This water is “__________ __________” and forms a __________bulge. As Earth __________, different places on the planet’s surface through the areas of __________bulges and have the change in water levels.

Tidal Bulges – High Tide In places where there are tidal bulges, ________ ___________is occurring along the coastlines. Tidal Bulges – Low Tide In places __________ the bulges, ______tide is occurring

Tides occur when Earth __________beneath the bulge A tidal day is _____hours _____minutes long because the moon rises _____minutes later each day

Earth-Moon System The moon’s __________ attracts the __________ toward it The Earth-Moon system __________ once a month (27.3 days) around the system’s center of mass

Tides occur when __________ __________ beneath the bulge A tidal _____ is 24 hours 50 minutes long because the moon rises 50 minutes __________ each day

Earth’s rotation = _____ hours (one day) Moon’s rotation = 24 hours and 50 minutes (_________ day) Tides occur 50 minutes later every day because of the __________ __________ difference.

Variations in Tides The moon can also move ______ degrees above or below the ________ each month Tidal bulges are offset relative to this change

TIDAL RANGE Tidal range is the __________between ________ and ________ tide.

Sun-Earth-Moon System Ocean responds to __________ and __________ forces of the _______ too

Sun’s Gravity and Tides The Sun is so __________that its __________also affects tides. At times, the __________and __________pull together on Earth’s waters in the __________direction. At other times they pull in __________directions.

__________ Tides When the sun, Earth and moon are __________, __________ and _________ tides are additive Results in __________ high tides and __________ low tides Occur at two week intervals during _____ moons and _____ moons

_______ Tides When the sun, Earth and moon are at ______ __________, the __________ tide will reduce the _________ tide Results in __________ high tides and __________ low tides Occur at two week intervals, arriving one week after the spring tide (during _____ quarter and _____ quarter moons)

Tides are __________ in North America in the __________because the Earth is slightly ________ to the Sun in winter.

Tides are also __________ at times during the month when the moon and earth are __________ together.

Daily Tide Cycle Most seashores have _____tides every day – _____high tides and _____low tides. A __________of from low to high tide or vice versa takes about _____hours and ______minutes. Changes in tides can be drastic (can notice) or or less dramatic (can’t notice).

Monthly Tide Cycle Changes in the __________of Earth, the Moon, and Sun affect the __________of tides during a month.

______________ is how often tides occur ______________ is how often tides occur. There are some exceptions but basically there are 3 types: __________ = 2 equal high and low tides per day each 6 hours - 12 ½ minutes apart ex: east coast of U.S. 2. __________ = 1 high and 1 low tide per day each 12 hours - 25 minutes apart ex: Gulf of Mexico, S.E. Asia 3. __________ = 2 high tides and 2 low tides of unequal range each 6 hours - 12 ½ minutes apart ex: west coast of U.S.

Importance of Tides Greatly influences __________ marine life Different organisms have adapted to areas within the __________ zone ______ use the tides to exit and enter port Tidal power is the ______ ______ ______ _______ that has been __________ used on a large scale