2 TidesTides are the daily changes in the elevation of the ocean surface. Tides are the daily rise and fall of the Earth’s waters on its coastlines. Tides are caused by the interaction of the Earth, the moon and the sun. A. Tides form from the gravitational attraction exerted upon the Earth by the moon. B. Tidal Cycle-Is influenced by the sun and moon. When they are aligned together their forces are added. Gravity is the force exerted by an object that pulls another object toward it. As the distance between two objects is greater the force becomes weaker.
3 Daily Tides Tides happen regularly no matter what the wind is doing Tides occur in all bodies of water but are most noticeable in oceans.High Tide- as the tide comes in toward the beach and reaches its highest pointLow Tide-as the tide flows back toward the sea and reaches its lowest point
4 Daily TidesThe moon gravity pulls on the water on the Earth’s Surface. The moon pulls on the water on the side closest to it more than it pulls on the center of the earth. This pull creates a Tidal bulge, a bulge of water on the side of the earth that is facing the moon . On the other side of the earth is a bulge of water that is pulled less strongly than the center of the earth. Where the tidal bulges are is where high tides occur. As the earth rotates different part of the earth's surface pass by these areas and experience the water level changes.
5 The Daily Tidal CycleAll areas of the world oceans pass under the moon every 24 hours and 50 minutes. The cycle takes more than one day, each day the tides occur at different timesEvery coastal area has at least one high tide and one low tide every dayFactors which influence the daily Tidal patterns are:The earth’s surfaceShape of the ocean floor/coastlineCoriolis effect
6 May 24 Agenda Question of the day Finish tide notes Finish study guide Go over answers
7 Monthly Tide CycleThe sun’s gravity also effects the Earth, even though it is far away it is very large. The sun’s gravity pulls the earth’s water toward it. Sometimes the moon and sun pull the earth’s water in the same direction other times they pull in different directions.
8 Spring tidesTwice a month at the new moon and the full moon, the sun and moon are lined up.These combined gravitational pulls cause the greatest tidal ranges.Spring comes from the word to jump and does not refer to the season!!!
9 Neap TidesAt the first quarter (waxing) and third quarter (waning) moons, the sun and moon pull at right angles to each other.Least tidal range due to the sun’s gravity pulling some of the water away from the tidal bulge facing the moon thus evening out the difference between low and high tide.