1 Name four branches of oceanography Describe at

1. Name four branches of oceanography. Describe at least five reasons why it is important for people to learn about the oceans. physical oceanography, chemical oceanography, marine geology, and marine ecology. Ocean waters serve as a source of food and valuable minerals, commerce, and provide a place for both recreation and waste disposal.

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. Salinity: 1 of 2 salinity is the total amount of dissolved material in grams in one kilogram of sea water.

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. Most marine creatures keep the salinity inside their bodies at about the same concentration as the water outside their bodies because water likes a balance. If an animal that usually lives in salt water were placed in fresh water, the fresh water would flow into the animal through its skin. If a fresh water animal found itself in the salty ocean, the water inside of it would rush out. The process by which water flows through a semi-permeable membrane (a material that lets only some things pass through it) such as the animal's skin from an area of high concentration (lots of water, little salt) to an area of low concentration (little water, lots of salt) is called osmosis. Did you ever wonder why the oceans are filled with salt water instead of fresh? Just where did the salt come from? And is it the same salt you find on a dining room table? Most of the salt in the oceans came from land. Over millions of years, rain, rivers, and streams have washed over rocks containing the compound sodium chloride (Na. Cl), and carried it into the sea. You may know sodium chloride by its common name: table salt! Some of the salt in the oceans comes from undersea volcanoes and hydrothermal vents. When water evaporates from the surface of the ocean, the salt is left behind. After millions of years, the oceans have developed a noticeably salty taste. 2 of 2

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. Temperature : a physical property of a system that underlies the common notions of hot and cold Temperature and density share an inverse relationship. As temperature increases, the space between water molecules—also known as density, decreases. If the temperature of a liquid decreases the density will increase. At a temperature of 0 C with zero movement, water freezes and is at peak density. Salinity and density share a positive relationship. As density increases, the amount of salts in the water—also known as salinity, increases. Various events can contribute to change in the density of seawater. Salinity can decrease from the melting of polar ice or increase from the freezing of polar ice. Evaporation increases salinity and density while the addition of freshwater decreases salinity and density. 1 of 2

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. Temperature : a physical property of a system that underlies the common notions of hot and cold Seawater temperature map showing areas of warmer water in red and areas of cooler water is blue. White areas represent ice. 2 of 2

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. Density : physical characteristic, and is a measure of mass per unit of volume of a material or substance 1 of 2

2. Define salinity, temperature, and density, and describe how these important properties of seawater are measured by the physical oceanographer. Discuss the circulation and currents of the ocean. Describe the effects of the oceans on weather and climate. While surface currents are driven mainly by wind, deep water circulation is driven by gravity. Cold and salty ocean surface water in the North Atlantic and elsewhere will slowly sink downward until it reaches a level of equal density. If the water is more dense (colder and/or saltier) then any other water in the deep ocean, it will sink all the way to the sea floor. Once the water reaches a level of equal density, the water spreads out. So in this way the deep ocean is stratified into horizontal layers, with water of higher and higher density sinking to deeper and deeper layers. The water that sinks in the North Atlantic flows all the way past the equator into the Southern Hemisphere. The water then flows past Antarctica and into the Pacific and Indian Oceans. Here, some of the deep waters are warmed and so rise again to the surface and to the surface circulation system. This conveyor belt cycling (pictured above) of the ocean waters is a simplification of the global ocean circulation. Still, it helps to show the basic idea of ocean water circulation from the surface to the depths of the ocean back to the surface again. In reality, deep water circulation is interrupted or diverted by ridges, rises and other underwater obstacles. 2 of 2

3. Describe the characteristics of ocean waves. Point out the differences among the storm surge, tsunami, tidal wave, and tidal bore. Explain the difference between sea, swell, and surf. Explain how breakers are formed. Storm surge (which is the same as a tidal surge) is an offshore rise of water associated with a low pressure weather system, typically a tropical cyclone. Waves are caused by the wind blowing over the surface of the ocean. A tsunami is a series of water waves, that is caused when a large volume of a body of water, such as an ocean, is rapidly displaced.

3. Describe the characteristics of ocean waves. Point out the differences among the storm surge, tsunami, tidal wave, and tidal bore. Explain the difference between sea, swell, and surf. Explain how breakers are formed. The swell or crest of surface ocean water created by the tides. A tidal bore is a large movement of water formed by the funneling of the incoming tide into a river or narrow bay

3. Describe the characteristics of ocean waves. Point out the differences among the storm surge, tsunami, tidal wave, and tidal bore. Explain the difference between sea, swell, and surf. Explain how breakers are formed. Breaking Waves. As waves approach landmasses, the wave base begins to contact the sea floor and the wave's profile begins to change. This friction slows the circular orbital motion of the wave's base, but the top continues at its original speed. In effect, the wave begins leaning forward on its approach to shore. When the wave's steepness ratio reaches 1: 7, the wave's structure collapses on top of itself, forming a breaker. A spilling breaker is the classic rolling wave coming up a gradually sloping sandy beach. The long incline drains the energy of the wave over a large area. A plunging breaker approaches a steeper beachfront and forms a curling crest that moves over a pocket of air. The curling water is traveling faster

4. Draw a cross-section of underwater topography. Show what is meant by: 1. Continental shelf 2. Continental slope, and 3. Abyssal plain Name and put on your drawing the following: seamount, guyot, rift valley, canyon, trench, and oceanic ridge. Compare the depths in the oceans with the heights of mountains on land. 1 of 4

The continental shelf is the extended perimeter of each continent and associated coastal plain, and was part of the continent during the glacial periods, but is undersea during interglacial periods such as the current epoch by relatively shallow seas (known as shelf seas) and gulfs. 2 of 4

Continental slope The shelf usually ends at a point of decreasing slope (called the shelf break). The sea floor below the break is the continental slope. Below the slope is the continental rise, which finally merges into the deep ocean floor, the abyssal plain. The continental shelf and the slope are part of the continental margin. 3 of 4

Abyssal plains are flat or very gently sloping areas of the deep ocean basin floor. They are among the Earth's flattest and smoothest regions and the least explored. Abyssal plains cover approximately 40% of the ocean floor and reach depths between 2, 200 and 5, 500 m (7, 200 and 18, 000 ft). They generally lie between the foot of a continental rise and a mid-oceanic ridge. 4 of 4

5. List the main salts, gases, and nutrients in sea water. Describe some important properties of water. Tell how the animals and plants of the ocean affect the chemical composition of seawater. Explain how differences in evaporation and precipitation affect the salt content of the oceans. Salinity map showing areas of high salinity (36 o/oo) in green, medium salinity in blue (35 o/oo), and low salinity (34 o/oo) in purple. Salinity is rather stable but areas in the North Atlantic, South Pacific, Indian Ocean, Arabian Sea, Red Sea, and Mediterranean Sea tend to be a little high (green). Areas near Antarctica, the Arctic Ocean, Southeast Asia, and the West Coast of North and Central America tend to be a little low (purple). 1 of 5

5. List the main salts, gases, and nutrients in sea water. Describe some important properties of water. Tell how the animals and plants of the ocean affect the chemical composition of seawater. Explain how differences in evaporation and precipitation affect the salt content of the oceans. Dissolved Gases The concentration of dissolved oxygen and carbon dioxide are very important for marine life forms. Although both oxygen and carbon dioxide are a gas when outside the water, they dissolve to a certain extent in liquid seawater. Dissolved oxygen is what animals with gills use for respiration (their gills extract the dissolved oxygen from the water flowing over the gill filaments). Dissolved carbon dioxide is what marine plants use for photosynthesis. 2 of 5

5. List the main salts, gases, and nutrients in sea water. Describe some important properties of water. Tell how the animals and plants of the ocean affect the chemical composition of seawater. Explain how differences in evaporation and precipitation affect the salt content of the oceans. Dissolved Nutrients Fertilizers, like nitrogen (N), phosphorous (P), and potassium (K), are important for plant growth and are called 'nutrients. ' The level of dissolved nutrients increases from animal feces and decomposition (bacteria, fungi). Surface water often may be lacking in nutrients because feces and dead matter tend to settle to the bottom of the ocean. Most decomposition is thus at the bottom of the ocean. In the oceans most surface water is separated from bottom water by a thermocline (seasonal in temperature and marginal polar regions, constant in tropics) which means that once surface nutrients get used up (by the plants there) they become a limiting factor for the growth of new plants. Plants must be at the surface for the light. Nutrients are returned to surface waters by a special type of current called 'upwelling' and it is in these areas of upwelling that we find the highest productivity of marine life. 3 of 5

5. List the main salts, gases, and nutrients in sea water. Describe some important properties of water. Tell how the animals and plants of the ocean affect the chemical composition of seawater. Explain how differences in evaporation and precipitation affect the salt content of the oceans. Marine organisms have evolved a wide variety of unique physiological and morphological features that allow them to live in the sea. Notothenid fishes in Antarctica are able to inhabit waters as cold as − 2° C (28° F) because of proteins in their blood that act as antifreeze. The chemical composition of the atmosphere also affects that of the ocean. For example, carbon dioxide is absorbed by the ocean and oxygen is released to the atmosphere through the activities of marine plants. The dumping of pollutants into the sea also can affect the chemical makeup of the ocean, contrary to earlier assumptions that, for example, toxins could be safely disposed of there. Tell how the animals and plants of the ocean affect the chemical composition of seawater. 4 of 5

5. List the main salts, gases, and nutrients in sea water. Describe some important properties of water. Tell how the animals and plants of the ocean affect the chemical composition of seawater. Explain how differences in evaporation and precipitation affect the salt content of the oceans. The ocean plays a key role in this vital cycle of water. The ocean holds 97% of the total water on the planet; 78% of global precipitation occur over the ocean, and it is the source of 86% of global evaporation Evaporation from the sea surface keeps the oceans from overheating. If there were no oceans, only land, the earth's greenhouse effect would lead to a surface temperature far too high. If the earth were in radiative equilibrium, with an atmosphere, the surface temperature would be 67°C. This does not happen because water evaporates from the surface, mostly from tropical seas, cooling the surface. The hydrological cycle keeps the greenhouse effect from heading to an overly hot planet. Sunlight warms the surface, mostly the tropical seas. The seas lose heat by evaporation (latent heat flux). Winds carry the vapor away from tropics. When the vapor condenses as rain, mostly in the ITCZ, it releases the latent heat, which warms the air, which drives the atmospheric circulation. Etc. This result of the hydrological cycle is of over riding importance. Without it we would not live on a habitable planet. 5 of 5

6. Describe some of the biologically important properties of seawater. Define benthos, nekton, and plankton. Name some of the plants and animals that make up each of these groups. Describe the place and importance of phytoplankton in the oceanic food chain. Benthos are the organisms which live on, in, or near the seabed, also known as the benthic zone. [1] They live in or near marine sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths. "A variety of marine worms": Seagrass

6. Describe some of the biologically important properties of seawater. Define benthos, nekton, and plankton. Name some of the plants and animals that make up each of these groups. Describe the place and importance of phytoplankton in the oceanic food chain. Nekton refers to the aggregate of actively swimming aquatic organisms in a body of water (usually oceans or lakes) able to move independently of water currents. Occacaris

6. Describe some of the biologically important properties of seawater. Define benthos, nekton, and plankton. Name some of the plants and animals that make up each of these groups. Describe the place and importance of phytoplankton in the oceanic food chain. Plankton consist of any drifting organisms (animals, plants, archaea, or bacteria) that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. Plankton are defined by their ecological niche rather than their phylogenetic or taxonomic classification. They provide a crucial source of food to more familiar aquatic organisms such as fish. the "conveyor belt" of the upgrowing larvae and the ovarium can be seen An amphipod (Hyperia macrocephala)

The main food sources for benthos are plankton and organic run off from land. The depth of water, temperature and salinity, and type of local substrate all affect what benthos is present. In coastal waters and other places where light reaches the bottom, benthic photosynthesizing diatoms can proliferate. Filter feeders, such as sponges and pelecypods, dominate hard, sandy bottoms. Deposit eaters, such as polychaetes, populate softer bottoms. Fish, sea stars, snails, cephalopods, and crustaceans are important predators and scavengers.

7. Do ONE of the following: A. Make a plankton net*. Tow the net by a dock, wade with it, hold it in a current, or tow it from a rowboat. Do this for about 20 minutes. Save the sample. Examine it under a microscope or high-power glass. Identify the three most common types of plankton in the sample. B. Make a series of models (clay or plaster and wood) of a volcanic island. Show the growth of an atoll from a fringing reef through a barrier reef. Describe the Darwinian theory of coral reef formation. C. Measure the water temperature at the surface, midwater, and bottom of a body of water four times daily for five consecutive days. You may measure depth with a rock tied to a line. D. Make a Secchi disk to measure turbidity (how much suspended sedimentation is in the water). Measure the air temperature. Note the cloud cover and roughness of the water. Show your findings (air and water temperature, turbidity) on a graph. Tell how the water temperature changes with air temperature. E. Make a model showing the inshore sediment movement by littoral currents, tidal movement, and wave action. Include such formations as high and low waterlines, low tide terrace, berm, and coastal cliffs. Show the offshore bars are built up and torn down. F. Make a wave generator. Show reflection and refraction of waves. Show groins, jetties, and breakwaters affect these patterns. Track and monitor satellite images available on the Internet for a specific location for three weeks. Describe what you have learned to your counselor.

8. Do ONE of the following: A. Write a 500 -word report on a book about oceanography approved by your counselor. B. Visit one of the following: (1) an oceanographic research ship, or (2) an oceanographic institute. Write a 500 -word report about your visit. C. Explain to your troop in a five minute prepared speech "Why Oceanography Is Important" or describe "Career Opportunities in Oceanography. " (Before making your speech, show your speech outline to your counselor for approval. ).

9. Describe four methods that marine scientists use to investigate the ocean, underlying geology, and organisms living in the water. Midwater scientists continued to dredge and trawl through the midwater ranges to gather specimens for study and identification. The mysterious depths of the midwater—the largest habitat on Earth— extend from several hundred feet below the ocean surface to just above the seafloor. The animals who live there have adapted to weightlessness, almost total darkness and infrequent meals. Because there’s almost no turbulence in the deep ocean, some animals, like jellies, have developed balloon-like, diaphanous bodies that are extremely fragile. 1 of 4

9. Describe four methods that marine scientists use to investigate the ocean, underlying geology, and organisms living in the water. Satellite-and Shuttle-based remote sensors are especially adept at providing image and physical property data regarding atmospheric and ocean surface conditions, usually scanned from meteorological/oceanographic platforms. Sea Surface Topography TOPEX/Poseidon and Jason-1, Scientists measure the sea surface height (SSH) to study surface currents, ocean circulation, and heat stored in the oceans, ocean and coastal tides and ocean floor topography. The satellites use a radar altimeter that sends short pulses of electromagnetic radiation downward analyzes the returned (reflected) signal. 2 of 4

9. Describe four methods that marine scientists use to investigate the ocean, underlying geology, and organisms living in the water. Surface Scientists measure the sea surface temperature (SST) to understand the ocean’s affect on weather, study global climate change and visualize surface water currents, turbulence and upwelling. The satellites measure thermal infrared radiation emitted by the sea surface to estimate its temperature. To correct for undetected clouds, which interfere with SST measurements, ship and buoy near-surface temperature measurements are required to calibrate the SST values. Global SST maps are a composite of cloud-free data collected over a week or a month. 3 of 4

9. Describe four methods that marine scientists use to investigate the ocean, underlying geology, and organisms living in the water. Ocean Floor The U. S. Geological Survey collects data from a variety of instruments to map the sea floor and its underlying geology scientists will trawl the ocean floor at up to 2000 metres depth, using both Agassiz-trawl fitted with a closed net as well as a Box-corer. The two methods are complementary. With the Agassiz-trawl a corridor of the sea floor is swept to catch all the species on the way in a mixed form. On the other hand the Box-corer is cast and once it hits the bottom it takes a 50 cm x 50 cm sample thereof for subsequent analysis on deck. With this sample we can quantify the number of each species per square metre, its biomass, and so on. Thus it is known as a quantified sample of the ocean floor. 4 of 4

Mt. Lake District Circle 10

* May be done in lakes or streams. CREDITS www. crystalinks. com/oceanography Wayne Ellis bsagptx@yahoo. com