1. Earth's ozone layer on track to recovery, scientists report September 10, 2014
Earth's protective ozone layer is well on track to recovery in the next few decades thanks to concerted international action against ozone depleting substances, according to a new assessment by 300 scientists.
The Assessment for Decision-Makers is the first comprehensive update in four years.
The stratospheric ozone layer, a fragile shield of gas, protects Earth from harmful ultraviolet rays of the sun. Without the Montreal Protocol and associated agreements, atmospheric levels of ozone depleting substances could have increased tenfold by According to global models, the Protocol will have prevented 2 million cases of skin cancer annually by 2030, averted damage to human eyes and immune systems, and protected wildlife and agriculture, according to UNEP.
"There are positive indications that the ozone layer is on track to recovery towards the middle of the century. The Montreal Protocol -- one of the world's most successful environmental treaties -- has protected the stratospheric ozone layer and avoided enhanced UV radiation reaching the earth's surface," said UN Under-Secretary-General and UNEP Executive Director Achim Steiner.
"However, the challenges that we face are still huge. The success of the Montreal Protocol should encourage further action not only on the protection and recovery of the ozone layer but also on climate. "International action on the ozone layer is a major environmental success story," said WMO Secretary-General Michel Jarraud. "This should encourage us to display the same level of urgency and unity to tackle the even greater challenge of climate change.

2. Enough Wind to Power Global Energy Demand: New Research Examines Limits Sep. 9,
There is enough energy available in winds to meet all of the world's demand. Atmospheric turbines that convert steadier and faster high-altitude winds into energy could generate even more power than ground- and ocean-based units.
Surface winds were defined as those that can be accessed by turbines supported by towers on land or rising out of the sea. High-altitude winds were defined as those that can be accessed by technology merging turbines and kites. The study looked only at the geophysical limitations of these techniques, not technical or economic factors.
Using models, the team was able to determine that more than 400 terrawatts of power could be extracted from surface winds and more than 1,800 terrawatts could be generated by winds extracted throughout the atmosphere.
Today, civilization uses about 18 TW of power. Near-surface winds could provide more than 20 times today's global power demand and wind turbines on kites could potentially capture 100 times the current global power demand.

3. CHAPTER 3 Marine Provinces
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Chapter Overview
The study of bathymetry charts ocean depths and ocean floor topography.
Echo sounding and satellites are efficient bathymetric tools.
Most ocean floor features are generated by plate tectonic processes.
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Bathymetry
Measures the vertical distance from the ocean surface to mountains, valleys, plains, and other sea floor features
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Measuring Bathymetry
Soundings
Poseidonus first sounding 85 B.C.
Line with heavy weight
Sounding lines used for 2000 years
Unit of measure is a fathom
1.8 meters (6 feet)
First systematic measurements – HMS Challenger 1872
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7. Challenger Expedition
Sailed from 1872 – 1876
Modified an old Navy ship for true oceanographic studies.
Identified over 4700 previously unidentified species.
Collected specimens and took depth readings over entire ocean.
In 1875, found deepest depth of ocean to be 26,850 ft.

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Measuring Bathymetry
Echo Soundings
Echo sounder or fathometer
Reflection of sound signals
German ship Meteor identified mid-Atlantic ridge in 1925
Lacks detail
May provide inaccurate view of sea floor
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Echo Sounding Record
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Measuring Bathymetry
Precision Depth Recorder (PDR)
1950s
Focused high frequency sound beam
First reliable sea floor maps produced
Helped confirm sea floor spreading
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Measuring Bathymetry
Modern Acoustic Instruments
Side scan sonar
GLORIA (Geological Long-range Inclined Acoustical instrument)
Sea MARC (Sea Mapping and Remote Characterization)
Can be towed behind ship to provide very detailed bathymetric strip map
Multi-beam echo sounder
Seabeam
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Side Scanning Sonar
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17. SONAR = sound waves

18. Sound waves Travel ~1500 meters per second in water Or 3355 mph This is 4x faster than on land (768 mph) problem???

19. For marine mammals, sound is very important
For marine mammals, sound is very important. Sight and smell are difficult due to water environment. Why sound??

20. Whale Sounds: Echolocation Find food (tooth whales..YES)
SEX Find opposite sex? Chase away competition? Sell yourself?
Enjoyment?

21. Noise Pollution
Navy SONAR
Increased boat/ship traffic (engines/propellers/sonar) means more noise. In past 30 years, some whale species have been increasing the level of their communication. WHAT?????
If you cannot find a mate and reproduce you go extinct. The ocean is a big place……….

23. Sea Floor Mapping from Space
Uses satellite measurements
Measures sea floor features based on gravitational bulges in sea surface
Indirectly reveals bathymetry
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Measuring Bathymetry
Seismic Reflection Profiles
Air guns
Strong, low-frequency sounds
Details ocean structure beneath sea floor
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25. Seismic Reflection Profile
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Ocean Provinces
Three Major Provinces
Continental margins
Shallow-water areas close to shore
Deep-ocean basins
Deep-water areas farther from land
Mid-ocean ridge
Submarine mountain range
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Ocean Provinces
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Continental Margins
Passive or Active
Passive
Not close to any plate boundary
No major tectonic activity
Example: East coast of United States
Active
Associated with convergent or transform plate boundaries
Much tectonic activity
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29. Active Continental Margins
Convergent or Transform
Convergent Active Margin
Oceanic-continent convergent plate boundaries
Active continental volcanoes
Narrow shelf
Offshore trench
Example: Western South America
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30. Passive and Active Continental Margins
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31. Continental Margin Features
Continental shelf
Shelf break
Continental slope
Continental rise
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32. Passive Continental Margin Features
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Continental Shelf
Flat zone from shore to shelf break
Shelf break is where marked increase in slope angle occurs
Geologically part of continent
Average width is 70 km (43 miles) but can extend to 1500 km (930 miles)
Average depth of shelf break is 135 meters (443 feet)
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34. Active vs Passive Shelf

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Continental Slope
Where deep ocean basins begin
Topography similar to land mountain ranges
Greater slope than continental shelf
Averages 4° but varies from 1–25° gradient
Marked by submarine canyons
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Submarine Canyons
Narrow, deep, v-shaped in profile
Steep to overhanging walls
Extend to base of continental slope, meters (11,500 feet) below sea level.
Carved by turbidity currents
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Turbidity Currents
Underwater avalanches mixed with rocks and other debris
Sediment from continental shelf
Moves under influence of gravity
Sediments deposited at slope base
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Abyssal Plains
Extend from base of continental rise
Some of the deepest, flattest parts of Earth
Suspension settling of very fine particles
Sediments cover ocean crust irregularities
Well-developed in Atlantic and Indian oceans
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41. Passive and Active Continental Margins
Smaller sediment size = greater settling distance

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Abyssal Plains
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43. Ocean Trenches and Volcanic Arcs
Convergent margins generate ocean trenches.
Deepest part of oceans
Most in Pacific Ocean
Deepest trench – Mariana Trench at 11,022 meters (36,161 feet)
Volcanic arc on nonsubducted ocean plate
May produce island arc, e.g., Japan
Continental arc on land
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Pacific Ring of Fire
Margins of Pacific Ocean
Majority of world’s active volcanoes and earthquakes
Marked by convergent boundaries
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45. Ocean Trenches and Ring of Fire
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Mid-Ocean Ridge
Longest mountain chain
On average, 2.5 km (1.5 miles) above surrounding sea floor
Wholly volcanic
Basaltic lava
Divergent plate boundary
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Mid-Ocean Ridge
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48. Mid-Ocean Ridge Features
Central rift valley downdropped by seafloor spreading
Fissures and faults in rift valley
Seamounts – tall volcanoes
Pillow lava or pillow basalt – shapes formed when hot basaltic lava quickly cools
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49. Mid-ocean Ridge Features
Hydrothermal Vents
Sea floor hot springs
Foster unusual deep-ocean ecosystems able to survive without sunlight
Warm water vents – temperatures below 30°C (86°F)
White smokers – temperatures from 30–350°C (86–662°F)
Black smokers – temperatures above 350°C (662°F)
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Hydrothermal Vents
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52. Oceanography Tuesday 9/23 EXAM #1 HW #1 Due TODAY
Tuesday 9/16 Long Island
Thursday 9/18 Chapter 4
Tuesday 9/23 EXAM #1
Thursday 9/25 No School
Tuesday 9/30 HW #2 Due

53. End of CHAPTER 3 Marine Provinces
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54. Next Wednesday Feb 8 EXAM 1 covering Chapter 1, 2, 3, 4
Next Monday – Chapter 4
Yes—the day after the Super Bowl so go to sleep right after the game ends
Next Wednesday Feb 8 EXAM 1 covering Chapter 1, 2, 3, 4

55. Wednesday Feb 9 Chap 4 Then Plankton Lab Monday Feb 14 My Valentines Gift to you Oceanography Exam #1 Chap 1, 2, 3, 4

56. Fracture Zones and Transform Faults
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57. Transform Faults and Fracture Zones
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Hypsographic Curve
Shows relationship between height of land and depth of ocean
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Hypsographic Curve
70.8% of Earth covered by oceans
Average ocean depth is 3729 meters
Average land elevation is 840 meters
Uneven distribution of areas of different depths/elevations
Variations suggest plate tectonics at work
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Oceanic Islands
Volcanic activity
Hotspots
Island arcs
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61. Mid-Ocean Ridge Features
Seamount
Pillow lava
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62. Active Continental Margins
Transform Continental Margin
Less common
Transform plate boundaries
Linear islands, banks, and deep basins close to shore
Example: Coastal California along San Andreas Fault
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Continental Shelf
The type of continetnal margin determines the shelf features.
Passive margins have wider shelves.
California’s transform active margin has a continental borderland.
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Continental Rise
Transition between continental crust and oceanic crust
Marked by turbidite deposits from turbidity currents
Graded bedding in turbidite deposits
Deposits generate deep-sea fans, or submarine fans
Distal ends of submarine fans becomes flat abyssal plains
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65. Abyssal Plain Volcanic Peaks
Poke through sediment cover
Below sea level:
Seamounts, tablemounts, or guyots at least 1 km (0.6 mile) above sea floor
Abyssal hills or seaknolls are less than 1 km (0.6 mile) above sea floor
Above sea level:
Volcanic islands
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66. Chikyu Sets a New World Drilling-Depth Record of Scientific Ocean Drilling Sep. 6, 2012
Scientific deep sea drilling vessel Chikyu sets a world new record by drilling down and obtains rock samples from deeper than 2,111 meters below the seafloor off Shimokita Peninsula of Japan in the northwest Pacific Ocean.
Chikyu is the state-of-the-art scientific research vessel, capable of drilling as much as 10,000 m below sea level. It is designed to reach the deeper part of the Earth such as the mantle, the plate boundary seisomogenic zones and the deep biosphere.