QUESTION OF THE DAY What is an event that you thought was going to be very scary, but actually wasn’t?

1910 – Halley’s Comet On this date Earth passed through the tail of Halley’s Comet This was the closest Earth has been to a comet in recorded history. People were very afraid of this event because a few years earlier astronomers found the poison gas cyanogen in a comet Even though they were assured that it was only trace amounts it didn’t stop opportunist from taking advantage and they sold “Comet Pills” to cover the effects of cyanogen. No one died due to comet issues.

What is a comet? What makes it different? Comet is an block of ice or rock that is from outside out solar system that happens to come visit Asteroid/meteors orbit within our solar system Comets tend to have a “tail” because they are mostly made of ice which is melting behind it The direction of the comet’s tail does NOT show the direction the comet is going

Halley’s/Voyager

Interim Reports and SOL Info SOL is MAY 25- NEXT WEDNESDAY 1 st block will be in T-24 4 th block will be in the media center

Currents Review What are the circles in the center of the currents called that typically contain trash washed into the ocean? Gyre What directions do the currents spin in the north and south hemisphere? Clockwise in the north, Counterclockwise in the south Which side of the continent will get warmer weather due to the current flowing from the equator towards the north pole? East side of continents

Waves

What are they? Transfer of energy through a liquid. One of the few ways we can visualize energy moving from one place to another. Dropping a rock in a pond can create waves on a small scale Storms far away often are the source of ocean waves. Wind moves the surface and that energy spreads out

Parts of a Wave These parts are mostly the same as any other wave type (sound, radio, cell phone, wifi) Crest – Top of a wave Trough – Bottom of a wave Wave Height – The vertical distance between a trough and a crest Wavelength – Distance from a crest of one wave to the crest of the next. Shows how quickly we can expect waves Wave Period – Time it takes for one full wave to pass a certain point. Shows how fast they are moving.

Parts of a Wave

Wave Motion Waves can travel a great distance in water because it encounters little resistance. Waves generated in Antarctica have been measured to travel more than 10,000km and break in Alaska The water itself isn’t moving with the waves. This means that the water in Antarctica isn’t making that trip, just passing the energy on by way of the waves The energy moves in a circular motion in the water, decreasing the deeper it goes until at have a wave length deep, it is essentially gone

Breaking waves This can happen in two ways First way is the crest gets so high that the water simply can’t stay together anymore and it breaks Think of a pirate movie with a bad storm in the ocean

Breaking Waves Second is what we are more used to with waves at the beach When water is in the open water it is not affected by the depth because that wave loses energy at have a wave length deep. When the water comes to the shore, the water get shallow and starts to invade on that energy making it lower the wavelength and go higher, causing it to break This is known as Surf

Tides Tides are the regular changes in elevation of water Referred to as High and Low Tides What causes the tides? The gravity of the Sun and Moon are not strong enough to have much effect on us because we are mostly solid. However it does have some influence on the water because naturally wants to move around

Moon Phases

Moon Position and Tides The tide will be directly tied with the location of the moon in relation to the sun and Earth If the moon and sun are on the same or direct opposite sides of the earth, New and Full Moon, this will cause the greatest fluctuation in the tide (higher highs, lower lows) Spring Tide If the moon is at a right angle, then it is the smallest tide changes. Quarter Moon Neap tide

Tidal Patterns There are three main types Diurnal – One high and one low tide each day Gulf of Mexico

Tidal Patterns Semidiurnal 2 high and 2 low each day Typically around the same heights East coast US

Tidal Patterns Mixed 2 high and 2 low each day Heights change West Coast US

Reading Guide 16.2 Quiz on oceans tomorrow Waves Tides Currents Ocean Floor Features All SOL Review sheets due tomorrow Keep studying for the SOL!

Exit Question What is an event or activity you have taken part in that was affected by waves or tides? How might you use the knowledge you learned today the next time you have that activity?