Introduction to Physical Oceanography STUDENT NOTES Date: 1. What do you know about solar radiation at different parts of the world?

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1 Introduction to Physical Oceanography STUDENT NOTES Date: 1 Warm up What do you know about solar radiation at different parts of the world? What affect does the tilt of the Earth have on the northern and southern hemisphere Intro What is physical oceanography? The atmosphere is the volume of that extends 90 km from the Earth s surface. Atmosphere Are earth s atmosphere and ocean intertwined? YES NO (circle) What are the three gases found in the atmosphere and ocean? (78%), (21%), and (.03%) Change in atmosphere can affect the ocean Change in ocean affects atmosphere - Ocean transports heat into the air which changes the local climate Layers of the Atmosphere - Lowest Layer - Temperature with altitude - Where weather happens and gases exchange from atmosphere and ocean (majority of breathable air) Atmosphere Layers - Temperature with altitude - What does the ozone layer do? - Some airplanes fly in this layer; breathable air also present - Temperature with altitude - What happens to space debris as it enters this part of the atmosphere? - Example: - Furthest Layer - What occurs in this layer?

2 Heating of the Earth s Surface Solar radiation from the sun heats the Earth s surface and powers atmospheric circulation What happens as radiation hits Earth? Differences in the heating of the atmosphere at different latitudes set gases in motion. This creates. The intensity of solar radiation varies with latitude What happens at lower latitudes? What happens at higher latitude? Unequal Solar Heating Diagram the direction of the sun s rays to the right Why does the Earth heat unevenly? Temperatures vary by - What causes heat to arrive at different times? - The tilted axis of Earth causes different parts of the Earth to heat at different rates This is the reason why the northern hemisphere is in while the southern hemisphere is in - The elliptical orbits cause the Earth to be of the year. More intense sunlight reaches the equator and the intensity of solar radiation towards the poles. Heat Budget At high latitudes the same amount of sunlight passes through the atmosphere but the same amount of sunlight is spread over a larger area In order to maintain a stable long-term temperature, what does Earth have to do? Excessive heat from the tropics tend to move to higher latitudes by and.

3 Coriolis Effect STUDENT NOTES Date: 2 Warm up Do pilots need to consider the spherical shape of the Earth in flight? Can they fly in a straight line? Complete the statement: air rises while air sinks. Coriolis Effect: tendency for a moving object to. Coriolis Effect causes winds to be able to move in ALL direction. It shapes and. Allows for distribution of heat, nutrients, and life. Coriolis Effect It is caused by the of the Earth Important for objects that move long distances/long time Where is the maximum deflection? Lowest/Negligible defection at which location? Which way in the northern hemisphere? Left/ Right (circle) Clockwise/Counter-clockwise (circle) Which way in the southern hemisphere? Left/ Right (circle) Clockwise/Counter-clockwise (circle) Convection: uneven heating causes air to raise and air to fall. Convection Winds do NOT just flow from poles to equator and back What is this change due to? The hot air at the equator will head either to north or south poles. At the same time, the cold air at the poles will move toward the equator. - This causes various weather patterns. Name THREE!

4 Hurricane Webquest STUDENT NOTES Date: 3 Warm up What do you know about Hurricanes? Where do they form? When? 1. What is a hurricane? 2. Where does the word "hurricane" come from? 3. Describe the three main PARTS of a hurricane: Webquest- Hurricane (Schoology Posted Links) 4. What conditions are needed for hurricane formation? 5. What type of pressure exists in a hurricane? 6. How do winds spin in Northern Hemisphere hurricanes? 7. What are hurricanes called in the Indian Ocean? What are hurricanes called in the western Northern Pacific and Philippines? 8. What "rules" are used to name hurricanes? 9. What name will be given to the 13th hurricane or tropical storm of 2014? 10. Why are some hurricane names retired? 11. When is the Atlantic hurricane season? What months have the most activity? 12. What "fuels" a hurricane? (Hint: Removing this "fuel" causes the hurricane to "die".)

5 13. What wind speeds are found in the following storms (report in mph) tropical depressions tropical storms hurricanes 14. Why do hurricanes hit the East coast of the US and not the West coast? 15. What is a storm surge? Why is it so dangerous? 16. The Saffir-Simpson scale classifies the damage caused by hurricanes into five categories. Copy and complete the following table: Webquest- Hurricane (Schoology Posted Links) Category # Wind Speed Height of Storm Surge Amount of Damage What is a hurricane watch? What is a hurricane warning? 18. List at least 3 different things you should do to prepare for a hurricane. 19. What should you do with your pet during a hurricane? 20. When and where was the deadliest hurricane in the US? How many people died?

6 Surface Circulation STUDENT NOTES Date: 4 Warm up What is a current? What can affect currents? Circulation within the ocean is significantly driven by. Ocean Circulation How does water transfer energy on the water s surface? It does this as it blows over the water causing horizontal movement. A water current will develop if wind blows at the same direction. What happens if the wind then stops blowing? The current continues to flow until internal friction, or friction with the sea floor, dissipates its energy Ocean circulation can occur as: : a horizontal movement of water in a well-defined pattern Ocean Currents Other than wind, what causes ocean currents? Earth s rotation:, Shape of Basin of water,, Temperature- cold water sinks/warm rises, Salinity- salt content of water Circulation (Density Driven) Refresh: How is the ocean stratified? How are density and salinity connected? Ocean Currents continued Two Types Surface Currents: Occurs in the top 400 m or less; What percent of the ocean currents are surface currents? Transfer heat from warmer to colder areas Similar to pattern of major wind belts What do these currents affect? Primarily horizontal motion Deep Currents: that result from differences in salinity and temperature Occurs below 400 m; What percent of ocean currents are deep currents? Produces very slow flow of deeper waters Vertical and horizontal motions

7 Winds and Surface Currents Rule: The Coriolis Effect is more pronounced the an object moves. 1. Wind blows only on the surface water layer (but it moves slower than the wind.) 2. This layer of water will also, but with less force (even slower). 3. This proceeds lower and lower (each layer is even slower). 4. What is this called? Ekman Spiral and Transport : a spiraling pattern of water direction caused because slower substances are more greatly influenced by the Coriolis Effect. : States that the overall movement of a current is to the right or left of the global wind direction Which way does it move in the Northern Hemisphere? Which way does it move in the Southern Hemisphere? : a circular pattern formed by the connection of several. Gyres and Eddies Made of multiple, connected currents in each ocean basin and named for the ocean and hemisphere they are found. Northern Hemisphere: 2 gyres with clockwise rotation; Southern Hemisphere: 3 gyres with counterclockwise rotation Gyres flow in a general area but they don t flow within perfectly defined paths they can vary due to wind strength. Eddies: Caused by friction with abrupt changes in adjacent waters, in water temperature, speed, and direction Can form large circular loops that can temporarily break away Eddies are important because: They can affect local by redistributing heat. Commercial fishing boats use eddies to locate fish. They can affect ship speed El Nino ENSO: is the change in location of warm and cold surface water every 2-7 years El Nino: La Nina: Effects of El Nino: result in worldwide weather changes. During El Nino years, the trade winds weaken and do not move warm water across the Pacific. What can occur during El Nino?

8 Deep Currents STUDENT NOTES Date: 5 Warm up What is the difference between surface currents and deep currents? What is sea level? REFRESH: Deep Currents Deep currents are that result from difference between what two things? The main gyres move and resulting in density variation lead to (sinking) Which sinks? Salty, dense water or less salty water (circle) There are different density layers found in the ocean What is density driven water flow called? This is because temperature and salinity together determine the of seawater Thermohaline/Density Driven Circulation T = temperature H = salt Density differences occur as a result of temperature and salinity Warm water holds salt than cold water so it is dense and rises toward the surface while cold, salt laden water sinks. As the warm water rises, the cold water is forced to rise through and fills the void left by the warm water. When cold water rises, it too leaves a void and the rising warm water is then forced, through to descend and fill this empty space creating Thermohaline circulation. - Coldest water is at the poles and have higher salinities because of low precipitation and the formation of sea ice.

9 Upwelling vs. Downwelling Upwelling Upward vertical current that brings cold deep nutrient rich water to the surface. This increases what? Increased diversity of life in upwelling zones and prove to be great fishing areas Some upwelling occurs when a wind blowing to shore pushes surface water out to sea due to. Where does upwelling occur? Downwelling A downward vertical current that pushes surface water deep into the ocean What is carried to the deep ocean? Combination of Thermocline deep water currents and Wind-driven surface currents. Below, trace the warm (red) and cold (blue) water. Great Ocean Conveyor Belt Unequal distribution of Equator heats up and redistributes heat Water moves as current from tropics toward higher latitudes. What is an example? What moving northward cools It is denser and sinks What else makes water more dense? Why would salinity in the water increase at the poles? This acts as a. Bringing cold water to the tropics and warm water to the poles and regulates climate. Sea Level Importance of Ocean Circulation What is sea level? This is driven by pressure gradient force When the level drops, the current carries water out Why is ocean circulation important? Ocean circulation affects the Earth in many ways Circulates and throughout the ocean Affects the Earth s climate Affects the transport and shipping industries What other things can be transported?

10 Waves STUDENT NOTES Date: 6 What is a wave? Waves and Movement When a wave passes through the ocean, individual water molecules move and but they DO NOT move or. Ex: Waves ripple away from the splash the water doesn t move away only the What determine how big a wave will become? : the strength of the wind; wind must be moving faster than the wave crests for energy to transfer from air to sea. Waves Fetch: How long must strong wind blow in one direction in order for large waves to be fully developed? : the length of the air current; high winds that blow only a short time will not generate large waves. Low winds that blow for a long time can generate very large waves Types of Progressive Waves Progressive Wave: the energy is transferred by of matter form one point to another and do not break. How are progressive waves classified? What are the 3 types of Progressive Waves? Longitudinal Wave Longitudinal Waves: vibration is in the Vibration is back and forth. (THINK or. What is this also known as? Provide examples of Longitudinal Waves Transverse Wave What are transverse wave? Which direction are vibrations in? Provide examples for Transverse Waves.

11 Orbital Waves Orbital Waves: transmit only through fluids as energy moves through the fluid in a motion as it passes. How is vibration? What is this also known as? Provide example for Orbital Waves. : the horizontal distance between two consecutive crests or troughs What is the HIGHEST point on a wave? LOWEST? : vertical distance between a wave crest and trough : the vertical distance between the still-water line and a wave crest or trough (How else can you think about it?) Wave Terminology : the time it takes for 2 consecutive crests or troughs to pass a stationary point What would you get with a LONG period? SHORT period? What is frequency? Celerity: speed of a wave. Wavelength/period Identify in the terms above in the following: What makes a wave break? Breaking Waves Explain the beaches that create the following breaking waves. Surging Wave: Plunging Wave: Spilling Wave: Which one do you think are on our SC Beaches?

12 Destructive Waves: Tsunami What is a Tsunami? What causes them? They re also called seismic sea waves. What else can they be called? Why is that incorrect? In open ocean, a tsunami may only have a wave height of a few feet and as the wave approaches shallow water, it builds to heights that can reach greater than 100 feet. When will tsunamis cause damage? AKA: Rip Current What causes it? How fast can it flow? How do you escape a rip current?

13 Tides STUDENT NOTES Date: 7 W ar m up What do you know about tides? Ocean Circulation: Tides Ocean Circulation is also driven by tides. Tides: are the rhythmic of sea surface levels. What three things cause the tides? The tides are caused by the gravitational pull of the on the ocean water (and the High vs. Low Tide to a lesser degree). This causes the. Water on the side of the Earth are pulled, causing a high tide. What is a high tide? Waters on the far side of the Earth are, causing a low tide. What is a low tide? Because the Earth spins, the place where high and low tides occur are constantly changing Tides: Spinning How often does it change? What do the bulges that create high tide follow? Inflow is AKA: Outflow is AKA: Midpoint between high and low tide creates a Gravitational Effect of the Sun on Tides: Spring Tride Sun has about of the power of the moon, and adds or subtracts from the lunar/moon tide. When are tidal bulges the largest? When sun and moon are, which produce very extreme tides. Spring Tide More storm damage during this tide How often does it occur? High tides are than normal and low tides are than normal Neap Tide What position are the Earth, Sun, and moon in? During a first or 3 rd quarter moon.

14 : two high, two low tide (most locations have this type) Ex: East Coast : successive high tides of different height Ex. West Coast : one high and one low Ex: Gulf of Mexico Tides: Types Why do Tides Vary? Number and size of tides can be affected by what things? Continents block westward passage of tidal bulges : the difference in ocean level between high tide and low tide Large wide basins tend to have a small tidal range than narrow, shallower basins Organisms are Affected by Tides Organisms that live in areas exposed during a low tide are especially affected during spring tides. What happens when there is movement of water during tidal changes? Many organisms time their according to the tides.