ACE Class Report – Oceanography 1.
Title: Oceanography: Exploring Earth’s Final Wilderness.
Instructor: Professor Harold J. Tobin
University of Wisconsin – Madison
Why I choose to Take This Class:
Oceanography weaves together Geology, Biology, Physics and Chemistry to illuminate the single ocean – vast, deep and mostly dark. This class gives me the opportunity to explore the ocean and understand the mystery of what lies beneath the surface of the waves.
What I learned from this Class:
Diving In- The Ocean Adventure:
71% of the earth is covered by ocean. Seawater and saltwater compose 97% of earth’s surface water. All the freshwater; polar Icecaps, lakes, rivers, stream and ponds and ground water that supplies our drinking water composed only 3% of the water on the planet. For nearly all of the 4.5 billion years history of the planet, the ocean has also been around. The Ocean has been essential to life; to the climate, that makes earth a habitable environment; and even to the geological forces of the planet.
Explorers, Navigator, Pioneering scientist:
Ocean exploration developed early technologies of shipbuilding and navigation, mostly as a by product of practical needs. Open ocean crossing by Polynesian, Nordic and European seafarer were accomplished through remarkably skilled navigation.
Chronometer – Precise clock originally used to determine longitude based on timing of local noon.
Sextant – Instrument used to measure the angle above the horizon of celestial objects that is used in navigation.
Stick Chart – Map like representation of islands, waves,and ocean current used in navigation by Micronesian and Polynesian seafarers.
Ocean Basics and Ocean Basins:
The ocean basins have their own unique physiographic features reflecting the geological origin. Major features include globe-encircling mid-ocean ridge mountain range; dep sea trenches, vast abyssal plains; and the continental shelves, slopes and rises. Each major ocean basin – Pacific, Atlantic, Artic, Indian has unique architecture, reflecting common processes but differing histories. The deep-ocean floor is underlain by oceanic crust, which is formed exclusively by volcanic processes and is completely different from the continental crust.
Mapping the sea – Soundings to Satellites:
Major basic features of the ocean floor were completely unknown until the late 19th century. Features as large as undersea mountains are still being discovered today through the progression of methods from line and weight sounding to acoustic echo sounding and sonar mapping to satellite altimetry. Modern oceanographic instruments digitally record currents, temperature, pressure, and salinity all over the world, mapping out the water itself.
Bathymetry – The measurement of the depth below sea level, is an inverse mirror of the topography on land.
Habitats – Sunlit Shelves to the Dark Abyss:
Just as on land, life in the ocean depends on habitat. Key ingredients for living organisms are: light, nutrients, temperature, pressure, chemistry and substrate. The geomorphology of the sea floor governs Benthic habitats from the Littoral zone to the Abyssal zone, wide, Sunlit Continental shelves host the most abundant life. Deep and completely dark Continental Slopes and Abyssal plains host a sur[prizing diversity and abundance of life too. Special environment host entire ecosystems not based on the sun’s energy but rather on plate tectonic energy from earth.
The shallow zone that is sunlit is called the Photic zone. By contrast everything below the photic zone is called the Aphotic.
Zone – the zone without any light.
The Spreading Sea Floor and Mid Ocean Ridges:
Plate Tectonic explains the the ocean basins are different from the continents because they form through seafloor spreading at the mid ocean ridges. Mapping of the mid Atlantic Ridge contemporaneously with the development of radioactive decay dating of Rocks and or rock magnetism led by Harry Hess and others to propose seafloor spreading in the 1960s. Alternating stripes of magnetized rocks due to earth’s magnetic reversals through time added support to the theory. Crust get older symmetrically on either side of the ridge, and ocean basin rocks are geologically very young in relation to the continents.
The Plunging Sea Floor and Deep Sea Trenches:
Ocean-Floor crust is created at the ridges, so it must be consumed elsewhere; subduction zones at deep sea trenches are the locations where ocean floor is recycled back into earth’s mantle,and transform faults link up the ridges and trenches, completing the plate Tectonic system. Subduction zones are the sites of the greatest earthquakes and Tsunami. Oceanic trenches as deep as 11,000 meters are the product of plate subduction. The plate Tectonic cycle is one of constant destruction, renewal, and reconfiguration of ocean basins, but the continents remain mostly intact.
The Formation Of The Earth and Its Ocean:
As the solar system formed, earth uniquely had the right conditions and ingredients for liquid water on the surface, and it has had an ocean for 4 billion years. Water was present from the initial accretion of the planet and separated from rock early in earth’s history; comets nay have added more water as well. the early earth was too hot for oceans to from, but gradual cooling took place through 25 million years of steady rain. Th moon formed through the collision of Mars sized body with the early earth.
The Early Ocean and The Origins Of Life:
Over the first 2/3 of the earth’s history, the ocean atmosphere,and the rocky surface changed from an early oxygen-poor state to the present oxygen rich system, and the development of life and photosynthesis dominates these changes. Early atmosphere had no oxygen but gradually changed to its present composition due to photosynthesis in the ocean. Liquid water is the most essential ingredient for life on earth; the ocean provided the only stable environment over the eons of early evolution.
Marine Sediments-Archives Of The Ocean:
After the ocean floor was created, sediments accumulated on it in layers that can be interpreted into a history of the ocean and climate through time. Marine sediments preserve clues to the environment at the time of their deposition in the type of fossils, the nature of grains of sand, and the chemical fingerprint of past climate. Many of the rock formations we see on land began as marine sediments and were incorporated into the continents through plate tectonic processes.
Offshore Oil And Gas – Resources and Risks:
Marine sediments are the source and host of all oil and gas deposits, the legacy of millions of years of life in the sea. The development of offshore oil brings societal needs and environmental and aesthetic concerns into conflict. The scale of the offshore drilling and production industry is immense, with billions of dollars invested in even a single platform. Smaller scale resources extraction from the sea include minerals, especially salt, and energy extraction through tide generators or thermal energy conversion.
The Enduring Chemistry of Seawater:
The unique and surprising properties of H2O, the water molecule, are responsible for the existence of a liquid ocean and a benign and relatively stable environment for life on earth. Water is the only common substance that exist in gaseous, liquid and solid form on the surface of earth. The incredible heat-retaining capacity of liquid water has acted as a global thermostat through geologic time. Light penetrates only about 200 meters into the ocean – The photic zone – which controls the habitat.
How will this class contribute to my success upon release:
Topics like oceanography improves my knowledge about the environment an its contribution to civilization. This knowledge will improve my critical thinking skills. The knowledge acquired will be taught to the communities which I volunteer my services.
ACE darasa Ripoti <unk> Oceanography 1. Kichwa: Oceanography: Kuchunguza Dunia's Mwisho Wilderness. Mwalimu: Profesa Harold J. Tobin Chuo Kikuu cha Wisconsin <unk> Madison Kwa nini mimi kuchagua kuchukua darasa hili: Oceanography weaves pamoja Jiolojia, Biolojia, Fizikia na Kemia ili kuangaza bahari moja <unk> kubwa, kina na zaidi giza. "Klasi hii inanipa fursa ya kuchunguza bahari na kuelewa fumbo la kile kilicho chini ya uso wa mawimbi.""" Kwa mfano, katika kipindi cha Diving in the Ocean Adventure, tulijifunza kwamba dunia ina bahari 71%. Maji ya bahari na maji ya chumvi hufanyiza asilimia 97 ya maji ya uso wa dunia. Maji yote ya chumvi, barafu za barafu, maziwa, mito, vijito na vidimbwi, na maji ya chini ya ardhi ambayo hutoa maji yetu ya kunywa, yanajumuisha asilimia tatu tu ya maji yote duniani. Katika historia ya sayari hii ya miaka bilioni 4.5 ya kibiolojia, bahari imekuwa karibu na dunia. Bahari imekuwa muhimu kwa maisha; kwa hali ya hewa, ambayo hufanya dunia mazingira ya kuishi; na hata kwa nguvu za kijiolojia za sayari. Watafiti, Navigators, Pioneers, Wanasayansi: Uchunguzi wa Bahari uliendeleza teknolojia za mapema za ujenzi wa meli na urambazaji, hasa kama bidhaa ya mahitaji ya vitendo. Meli za baharini za Polynesia, Nordic, na Ulaya zilivuka bahari kwa njia ya uendeshaji wa baharini wenye ustadi wa ajabu. Chronometer <unk> Saa sahihi awali kutumika kuamua longitudo kulingana na muda wa mchana wa ndani. Sextant <unk> Chombo kutumika kupima pembe juu ya upeo wa macho ya vitu vya angani ambayo ni kutumika katika urambazaji. Stick Chart  Ramani kama uwakilishi wa visiwa, mawimbi, na mkondo wa bahari kutumika katika urambazaji na Micronesian na Polynesian baharia. Ocean Basics na Basin Ocean: Basin bahari na yao wenyewe kipekee physiographic sifa kuonyesha asili ya kijiolojia. Sehemu kuu za eneo hilo ni safu ya milima inayozunguka dunia; mitaro ya bahari iliyo ndani sana, nyanda kubwa za chini ya ardhi; na mabonde ya bara, mteremko na vilima. Kila bonde kubwa la bahari - Pasifiki, Atlantiki, Aktiki, India - lina usanifu wa kipekee, unaoonyesha michakato ya kawaida lakini historia tofauti. Chini ya bahari ya kina kirefu kuna tabaka la bahari, ambalo hufanyizwa tu na michakato ya volkano na ni tofauti kabisa na tabaka la bara. Map ya bahari: Vipimo vya satellite: Vipengele vikubwa vya msingi vya sakafu ya bahari vilikuwa haijulikani kabisa hadi mwishoni mwa karne ya 19. Vitu kama vile milima ya chini ya bahari bado vinagunduliwa leo kupitia maendeleo ya mbinu kutoka kwa sauti ya mstari na uzito hadi sauti ya sauti na ramani ya sonar hadi altimetry ya satelaiti. Vifaa vya kisasa vya kuchunguza bahari huandika kwa njia ya kompyuta mawimbi, halijoto, shinikizo, na chumvi ulimwenguni pote, na hivyo kuchora ramani ya maji yenyewe. Bathymetry <unk> Upimaji wa kina chini ya usawa wa bahari, ni kioo kinyume cha topografia juu ya ardhi. Mazingira <unk> Shelves Sunlit to the Dark Abyss: Kama vile kwenye nchi kavu, maisha katika bahari hutegemea mazingira. Viungo muhimu kwa viumbe hai ni: mwanga, virutubisho, joto, shinikizo, kemia na substrate. Geomorphology ya sakafu ya bahari inaongoza makazi ya Benthic kutoka eneo la Littoral hadi eneo la Abyssal, shelves pana, Sunlit Continental huandaa maisha mengi zaidi. Mteremko wa Bara wenye kina kirefu na wenye giza kabisa na nyanda za Abyssal huandaa utofauti wa ajabu na wingi wa uhai pia. Mazingira maalum mwenyeji mifumo nzima ya ikolojia si kulingana na nishati ya jua lakini badala ya bamba tectonic nishati kutoka duniani. Eneo lisilo na kina kirefu linalopatikana kwa jua huitwa eneo la Photic. Kwa kutofautisha kila kitu chini ya eneo la photic huitwa Aphotic. Eneo <unk> eneo bila mwanga wowote. Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic Plate: Tectonic. Mapping ya Mid-Atlantic Ridge wakati huo huo na maendeleo ya tarehe ya uharibifu wa mnururisho wa miamba na au magnetism ya mwamba iliyoongozwa na Harry Hess na wengine kupendekeza kuenea kwa sakafu ya bahari katika miaka ya 1960. Mstari wa miamba yenye sumaku unaobadilika-badilika kwa sababu ya mabadiliko ya sumaku ya dunia kwa muda uliongeza utegemezo kwa nadharia hiyo. Makundi ya miamba ya bahari huzeeka kwa njia ya usawa upande wa mteremko, na miamba ya mabonde ya bahari ni ya vijana sana kwa kulinganisha na mabara. "Kutoka kwa ""subduction zones"" katika matundu ya bahari ya kina kirefu, mabonde ya bahari yanaunganisha mabonde na matundu, na kumaliza mfumo wa sahani ya Tectonic." Maeneo ya kuanguka kwa maji ni mahali ambapo matetemeko makubwa ya ardhi na Tsunami hutokea. Mifereji ya bahari yenye kina cha mita 11,000 ni matokeo ya kuanguka kwa mabamba. Mzunguko wa Tectonic ya sahani ni moja ya uharibifu wa mara kwa mara, upya, na marekebisho ya mabwawa ya bahari, lakini mabara hubaki hasa intact. Kuanzishwa kwa bahari: Kwa mfano, wakati mfumo wa jua ulipoanzishwa, dunia ilikuwa na hali sahihi na viungo kwa maji ya kioevu kwenye uso wake, na imekuwa na bahari kwa miaka bilioni 4. Maji yalikuwapo tangu kuunganishwa kwa sayari na kutenganishwa na mwamba mapema katika historia ya dunia; kometi nay pia zimeongeza maji zaidi. Dunia ya mapema ilikuwa moto sana kwa bahari, lakini baridi ya hatua kwa hatua ilitokea kupitia miaka milioni 25 ya mvua ya kudumu. Mwezi wa kwanza ulijitokeza wakati mwili wa ukubwa wa Mars ulipogongana na dunia ya mapema. Katika kipindi cha miaka miwili ya kwanza ya historia ya dunia, anga ya bahari na uso wa miamba ilibadilika kutoka hali ya mapema ya oksijeni-dogo hadi mfumo wa sasa wa oksijeni-tajiri, na maendeleo ya maisha na photosynthesis inatawala mabadiliko haya. Anga la mapema halikuwa na oksijeni lakini hatua kwa hatua lilibadilika kuwa muundo wake wa sasa kwa sababu ya fotosynthesis katika bahari. Maji ni kiungo muhimu zaidi cha uhai duniani, na bahari ndiyo iliyokuwa mazingira ya kudumu kwa miaka mingi ya mageuzi ya mapema. Baada ya sakafu ya bahari kuundwa, sediments zilizokusanywa juu yake katika tabaka ambazo zinaweza kutafsiriwa katika historia ya bahari na hali ya hewa kwa muda. Matope ya baharini huhifadhi dalili za mazingira wakati wa kuhifadhiwa kwao katika aina ya visukuku, asili ya chembe za mchanga, na alama ya kemikali ya hali ya hewa ya zamani. Mengi ya miamba ambayo tumepata duniani ni ya asili ya bahari na imesababishwa na miamba ya mabara ya dunia. Mafuta na Gesi ya Pwani: Rasilimali na Hatari: Sediments za baharini ni chanzo na mwenyeji wa amana zote za mafuta na gesi, urithi wa mamilioni ya miaka ya maisha baharini. Maendeleo ya mafuta ya pwani huleta mahitaji ya jamii na wasiwasi wa mazingira na urembo katika mgogoro. Kiasi cha sekta ya kuchimba visima na uzalishaji wa pwani ni kikubwa sana, na mabilioni ya dola zimewekezwa hata katika jukwaa moja. Uchimbaji wa rasilimali ndogo kutoka baharini ni pamoja na madini, hasa chumvi, na uchimbaji wa nishati kupitia jenereta za mawimbi au ubadilishaji wa nishati ya joto. "Kemia ya maji ya bahari: ""Hisi za kipekee na za kushangaza za H2O, molekuli ya maji, ni wajibu wa kuwepo kwa bahari ya kioevu na mazingira mazuri na thabiti kwa maisha duniani." Maji ni dutu pekee ya kawaida ambayo ipo katika gesi, kioevu na fomu imara juu ya uso wa dunia. Uwezo mkubwa wa maji ya kioevu wa kuhifadhi joto umekuwa kama thermostat ya ulimwengu katika nyakati za kijiolojia. Nuru huingia ndani ya bahari kwa mita 200 tu, eneo linaloongoza mazingira. Jinsi gani darasa hili litasaidia mafanikio yangu baada ya kutolewa: Mada kama vile oceanography inaboresha maarifa yangu kuhusu mazingira na mchango wake kwa ustaarabu. Ujuzi huo utaongeza uwezo wangu wa kufikiri kwa njia ya kukosoa. Ujuzi uliopatikana utafundishwa kwa jamii ambazo mimi kujitolea huduma zangu.