Chapter 12
MARINE SCIENCE TECHNOLOGY
I. Early Devices
A. John Harrison’s marine chronometer (1700s): early timing device that accurately kept
time on ships and allowed explorers to navigate better
II. Instruments and Methods of Obtaining Information
A. Secchi disk: black and white circular disk lowered into water to measure water
transparency, which indirectly reveals turbidity, clarity, and attenuation
B. coring device [corer]: obtains cylinders of sediment
C. Nansen bottle: early device used to obtain seawater samples at specific depths; takes
sample when it flips over; named after Fridjtof Nansen, the Arctic explorer
D. Niskin bottle: modification of the Nansen bottle that does not have to flip over
E. Ekman grab: device used to obtain samples of sediment from the bottom of a body of
water; Peterson grab is similar
F. hydrocast: the process of putting bottles on a wire and getting them to take samples of
water at certain depths and then retrieving them
G. pressure gauge: measures pressure
H. acoustic tomography: the use of sound waves to map seawater properties
I. depth recorder [echo sounder]: beams sound down through water and measures time it
took for sound to travel, which reveals depth
J. CTD [conductivity, temperature, depth] device: the name explains its uses
K. barometer: measures air pressure
L. plankton net: fine, cone-shaped, mesh net used to catch plankton
M. drogue: free-floating instrument that tracks currents
N. dredge: container connected to a mesh net that is dragged over the sea floor
1. epibenthic sled: modified dredge designed to capture small organisms
III. Diving
A. free diving: diving without air
B. scuba [self-contained underwater breathing apparatus]: allows people to dive underwater
for prolonged periods; developed in 1943 by Jacques-Yves Cousteau and Emile Gagnan
1. Aqualung: first form of scuba developed by Jacques-Yves Cousteau
2. heliox (helium, oxygen, hydrogen): gas mixture used for deep dives
3. record ocean dive was 534 m
C. atmospheric diving suit [ADS]: maintains atmospheric pressure for diver; famous
example is the Jim Suit, a particular model of the ADS
IV. Submersibles
A. classifications
1. deep submergence vehicle [DSV]
2. remotely operated vehicle [ROV]: robotic vessel
3. bathysphere: small, spherical vessel usually made of steel lowered into the ocean by a
cable; earliest form of submersible; Barton and Beebe pioneered its use
4. bathyscaphe [“deep boat”] (ex: Trieste): deep-diving submersible that uses a float
filled with an incompressible fluid to remain buoyant
B. Skinkai (6500 m): deepest-diving manned submersible in operation
C. Argo: unmanned vessel; discovered RMS Titanic in 1985; Robert Ballard led the search
D. Alvin (4500 m): manned submersible; found the first hydrothermal vents in 1977,
discovered a missing hydrogen bomb, and was the first manned submersible to visit RMS
Titanic
E. Jason/Medea: Jason is a remotely operated vehicle (ROV) attached to Medea, his base
V. Navigational Technologies
A. loran [long range navigation]: requires use of two radio broadcast stations
B. lidar [light detecting and ranging]
C. radar [radio detecting and ranging]: shows shoreline and surrounding vessels by
reflecting radio signals off of them
D. sonar [sound navigating and ranging] (similar to echolocation, which is the term for what
cetaceans use to communicate)
1. active: emitting sounds from an echo sounder in order to obtain picture of
surroundings; better than using light to look at surroundings in the ocean
2. passive: receiving sound from environment in order to make a picture of surroundings
VI. Renewable Ocean Energy Sources
A. ocean heat
1. ocean thermal energy conversion [OTEC]: utilizes the prominent thermocline of
warm tropical waters to heat fluid, which powers a turbine, then condense it
B. wave energy: up-and-down motion is harnessed by buoys, which move pistons
1. Limpet 500: world's first wave power plant that began operating in 2000 off the west
coast of Scotland on the island of Islay
C. tidal energy
1. the amount of useful tidal energy available to a power plant is based on the basin area
enclosed and the tidal range
2. Annapolis River estuary, Bay of Fundy: home of the only tidal power plant in North
America
D. current energy
E. wind energy
1. offshore windpower systems [OWPS]: capture wind energy on the sea
VII. Geochemical Ocean Sections [GEOSECS]: systematic program designed to increase
understanding of circulation patterns and mixing processes in the oceans; use rosettes to
capture seawater samples at different depths; this program measures temperature, salinity,
dissolved oxygen, pressure, and particulate content
VIII. Satellites
A. Seasat (1978): first truly oceanographic satellite; mission was a failure because it only
yielded 42 hours of data
B. TOPEX/Poseidon (1992-2006): first satellite to measure sea surface height, which
revealed ocean circulation patterns
C. Jason-1: measured sea surface height later on
D. SeaStar: holds the SeaWiFS instrument, which measures ocean surface productivity by
detecting the amount of chlorophyll in the ocean; this measurement is not always an
accurate measure of productivity because there are different efficiencies, and zooplankton
eat phytoplankton, causing a decrease in chlorophyll concentrations
IX. Other
A. Floating Instrument Platform [FLIP]: stable platform for instruments; designed by
Scripps Institution of Oceanography
B. icebreaker: any ship designed to navigate through ice; modern icebreakers can advance
through ice up to 1.8 m thick