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OCN331
• Goals: Qualitative & Quantitative• Joint Commitment re OCN331• Reading Materials—On-Line• Lectures & Discussions
– Rec. read chapters; – Access/bring PwrPt to class– Additional [timely] readings
• Examinations:Q30%, MT25%, F45%• Ethics
OCN331
• http://www.soest.hawaii.edu/oceanography/courses_html/OCN331/index.html
• Dr. Paul BienfangPhone: 956-7402Office: MSB 606email: [email protected]
• Dr. Hank Trapido-RosenthalPhone 956-9418Office: POST 105Email: [email protected]
OCN331
• How do the oceans make fish?
• How do we extract fish from the oceans?
• What other living resources do the world’s oceans hold?
• Why do we care?
In The Beginning…
I. The Universe Begins with a Bang15 billion years ago
II. Our Sun Forms5 billion years ago
III. The Earth Forms4.5 billion years ago
IV. First Signs of Life on Earth3.8 billion years ago - chemicals3.4 billion years ago - microbial
fossils
The Ancient Atmosphere and Ocean
I. The Earth Before Photosynthesis4.5 - 3.5 billion years ago
II. Marine Microbes Generate OxygenStarting 3.5 billion years ago
III. The Oceans Rust3.5 - 2.0 billion years ago
IV. An Oxygenic Atmosphere Evolves2.0 - 0.5 billion years ago
Atmospheric Oxygen
I. Stays between 15% and 35%
II. Below 15% - no such thing as fire
III. Above 35% - spontaneous combustion ofmost organic matter
And, CO2 concentrations have fluctuated
Low CO2 concentrations = ice age
High CO2 concentrations = interglacial
Atmospheric CO2 concentrations since the year 1000 AD estimated from
ice core data and monitoring of CO2 at Mauna Loa.
Some Wind and Current Fundamentals
I. Effect of Differential Heating on Atmospheric Circulation
II. The Coriolis Effect
III. Trade Winds and Westerlies
IV. Air-Sea Interactions
V. El Niño
Some effects of atmospheric circulation cells
Dry climate and high pressure in the vicinity of 30o latitude
Some effects of atmospheric circulation cells
Wet climate and low pressure in the vicinity of the equator and 60o latitude
Dry climate and high pressure in the vicinity of 30o latitude
In the Northern Hemisphere:
Things moving north curve east
Things moving west curve north
Things moving south curve west
Things moving east curve south
Deflection is to the RIGHT
Coriolis Effect II
In the Northern Hemisphere:
Air flowing FROM an area of high pressure curves to the right
Air flowing TOWARDS an area of low pressure curves to the right
Deflection is to the RIGHT
Coriolis Effect III
153045607590
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60Bermuda in the Age of Exploration
Gulf Stream
Westerlies
N E Trades
Bermuda
There are several major coastal upwelling regions in the world, including those along the coasts of California and Mauritania in the northern hemisphere…
Effects of Walker Cell circulation
Wet climate and low pressure at the western margin of the ocean basin near the equator
Dry weather and high pressure at the eastern margin of the ocean basin near the equator. Note that this is contrary to the effect expected from Hadley cell circulation.
Southern Oscillation Index
The Southern Oscillation Index (SOI) is a measure of the pressure differential between the southeastern Pacific (high pressure) and the western Pacific near the equator (low pressure). It is commonly taken to be the pressure differential between Easter Island and Darwin, Australia.
Because this pressure differential results from the circulation of the atmosphere, it is a convenient proxy for the intensity of atmospheric circulation and the strength of the Trade Winds.
I. High atmospheric pressure at 30° N and 30° S latitude governs major wind patterns
II. The Coriolis Effect deflects winds and currents to the RIGHT in the Northern Hemisphere
and to the LEFT in the Southern Hemisphere
III. These wind and current phenomena generate coastal UPWELLING of deep ocean water
IV. Variations in the strength of these winds andcurrents can lead to conditions (EL NIÑO)that disrupt upwelling
Things to Remember