Registration Problems? Please see... Melinda Peterson Geosciences Departmental Office 104 Wilkinson Hall petersom@geo.oregonstate.edu 737-1238.
Post on 23-Dec-2015
229 Views
Preview:
Transcript
Registration Problems?Please see...
Melinda PetersonGeosciences Departmental Office
104 Wilkinson Hallpetersom@geo.oregonstate.edu
737-1238
“Water World”“Earth is a unique
planet, possibly one of the few in the
galaxy that has water.Nearly 71% of it’s surface is ocean.
From space, Earth is brilliantly blue, white in places with clouds and ice, sometimes swirling with storms.
At it’s surface the ocean is in constant motion with powerful currents that stretch
for thousands of miles and towering waves. Beneath the ocean’s
surface lie hidden mountain ranges, vast
trenches tens of thousands of feet
deep, immense hot springs, and huge volcanoes spewing
molten rock in massive eruptions.”
-- T. Garrison
“Just the Facts…” Over 97% of the water on the Earth is in the
ocean. The average depth of the ocean is about
4000 meters. The Mariana Trench is 11,022 m deep, the
deepest spot on the planet.– 8 tons per sq. in.– Mt. Everest is “only” ~8667 m above sea level
“Just the Facts…” Mauna Kea on the Big Island of Hawaii,
measures ~10,600 m from the ocean floor, making it the tallest mountain on the planet (surpassing even Mt. Everest).
If the Earth’s contours were leveled to a smooth ball, the ocean would cover it to a depth of 2686 m.
“Just the Facts…” The ocean contains some 5 trillion tons
of salts– If dried and spread evenly, that mass would
cover the entire planet to a depth of 45 m. On a planetary scale the ocean is
insignificant.– Its average depth is a tiny fraction of the
Earth’s radius.– The blue ink representing the ocean on a
paper globe is proportionally thicker.
Why Study the Ocean? Major influence on weather and climate Source of food, energy, medical drugs Transportation Military significance Recreational resource Major influence on the health of the planet Culture and history
Historical Reviewof Oceanography
The 18th century was marked by– Improvements in navigation and
mapping
– Accumulation of data for charts Temperature, currents
In the United States, Benjamin Franklin (1769-1770) published the first chart of the Gulf Stream
Historical Reviewof Oceanography
(Cont.)
In Britain, James Cook (1768-1779)
– Constructed charts of coastlines especially for the South Pacific
– Secondary discovery the Hawaiian Islands
Historical Reviewof Oceanography
(Cont.)
Historical Reviewof Oceanography
(Cont.)
In the 19th century curiosity about the oceans increased and voyages for scientific purposes were initiated
Charles Darwin: British naturalist– Voyage of the Beagle (1831-1836), studied
geology and biology of the South American coastline
Developed theory of organic evolution based on natural selection
Published On the Origin of the Species (1859)
$1200!
Edward Forbes: British naturalist (1815-1854)– Proposed the hypothesis that no life (azoic)
existed in the oceans below 550 m
Historical Reviewof Oceanography
(Cont.)
Matthew Fontaine Maury: U.S. naval officer– Compiled information on winds and
currents– Published The Physical Geography of the
Sea (1855)– “Father of physical oceanography”
Historical Reviewof Oceanography
(Cont.)
C. Wyville Thompson: British explorer– Directed the Challenger Expedition (1872-1876)
First major scientific expedition Globe-encircling voyage Chemical, physical, and biological measurements
and collections Disproved Edward Forbes “azoic theory” by
collecting sea life from waters as deep as 9000 m
Historical Reviewof Oceanography
(Cont.)
Modern Oceanography Major interdisciplinary expeditions e.g., the Meteor
Expedition: German (1925-1927)– Bottom topography– Vertical profiles of salinity, temperature, oxygen
Subsequent growth, World War II, urgent need for information on the physical structure of the oceans
Geological Oceanography(Marine Geology)
Study of rocks and sediments & processes responsible for their formation.
Marine Geophysics
Study of rock structure in the ocean basin, properties of rocks such as
magnetism, occurrence of earthquakes.
Physical Oceanography
How and why ocean currents flow, air-sea interactions such as the generation of
waves by the wind.
Chemical Oceanography
Composition of sea water and the processes controlling and altering its
composition, including marine pollution.
Biological Oceanography(Marine Biology)
Organisms that live in the oceans and their relationships to the environment.
Today ocean research is conducted by Today ocean research is conducted by investigators in investigators in specialized marine specialized marine institutionsinstitutions, as well as universities, and , as well as universities, and state and federal agenciesstate and federal agencies
The emphasis is on interdisciplinary, The emphasis is on interdisciplinary, processprocess-oriented research and -oriented research and international cooperationinternational cooperation
Modern Oceanography (Cont.)
19031903www.sio.ucsd.eduwww.sio.ucsd.edu
19301930www.whoi.eduwww.whoi.edu
19491949www.ldeo.columbia.eduwww.ldeo.columbia.edu
Current and Future Oceanographic Research
greater focus on internationalinternational efforts and large scale interdisciplinary expeditions– Many scientists– Many ships
“remote sensing” “unmanned” platforms
TOPEX/Poseidon satellite launched in 1992.
Seasat-A, the first oceanographic satellite, was launched in 1978.
top related