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Founded in 1876, Texas A&M University is a U.S. public and comprehensive university offering a wide variety of academic programs far beyond its original label of agricultural and mechanical trainings. It is one of the few institutions holding triple federal designations as a land-, sea- and ...
A method designed to be optimal for analyzing short time series which can work with an SNR as low as 0. 6. No hypotheses are made about the actual series belonging to any hypothetical ensemble or infinite series; only the given data are used to find the probability of some a priori signal being contained in the data. A measure of the accuracy of the estimate can also be obtained.
Industry:Earth science
The application of underwater acoustics to investigations of biological patterns and processes in the sea. This has been traditionally divided into two distinct groups of investigators, those who study the sounds produced by marine organisms, and those who produce sounds and listen to the returning echoes to study the distributions of marine organisms.
Industry:Earth science
A project to study the effects of seasonal fluctuations in salinity, turbidity and sedimentation rates in the glacial fjords on Svalvard on how the diversity of ice flora and fauna is structured by stress gradients and the physical ice habitat. Also studied will be the zonation of macrobenthic organisms on hard bottom substrates and how this zonation changes longitudinally in the fjord against the general stress gradients. The work will involve several diving transects from inner to outer fjord. This project is being performed by the Norwegian Polar Institute under the leadership of Haakon Hop during 1996.
Industry:Earth science
A device developed by Athelstan Spilhaus in 1938 to measure temperature/depth profiles in the ocean, the bathythermograph was basically a reworking of a mostly unworkable device called an oceanograph built in 1934 by Carl-Gustav Rossby for the same purpose. It consisted of an open, rectangular frame in which a compressible bellows with a pen arm and stylus was mounted at one end. The stylus rested on a smoked glass slide and moved across it to scratch a record of ocean temperatures. The stylus also moved vertically with changes in depth and thus created a temperature/depth profile.
The bathythermograph (or BT) was further improved by Maurice Ewing and Allyn Vine in 1940. Their version responded more quickly to temperature changes and was streamlined so it could be lowered and raised more quickly from a moving ship than could the previous more unwieldy version. In 1940 WHOI started doing military research for the government, a large part of which was concerned with sonar and the use of BTs with it. Knowledge of the vertical temperature structure of the ocean was extremely helpful to sonar operators since sound speed in sea water is a strong function of temperature, and various types of vertical temperature profiles would lead to sound traveling differently in the ocean. BT data was also useful for adjusting the buoyancy or trim of submarines since it could help provide an estimate of how much ballast would be needed to move a submarine from periscope depth to greater depths. A strong thermocline would require much more ballast for the submarine to descend.
The military research also led to further improvements in the BT including better aerodynamics for more stable operation at higher speeds as well as moving the glass slide and stylus from within the BT to inside the submarine. By early 1943 many submarines were outfitted with and used BTs. In an extremely helpful quid pro quo, the glass slides were given to WHOI and Scripps after missions in both oceans, allowing charts of the vertical temperature structure of the ocean to be constructed. Over 60,000 slides from the North Atlantic alone were thus made available to oceanographers.
Industry:Earth science
The marine ecologic zone that lies deeper than the continental shelf but shallower than the deep ocean floor, i.e. those depths corresponding to the locations of the continental slope and rise. The depth range is from 100-300 m down to 1000-4000 m depending on such variables as the depth of the shelf break, the depth of light penetration, and local physical oceanographic conditions.
Industry:Earth science
A paleogeographic area during the late Precambrian and early Paleozoic that comprised north-western Europe, including most of what are now the U. K. , Scandinavia, European Russian and Central Europe. It formed the southeastern margin of the Iapetus Ocean and was moved by the subduction of that ocean (during the Caledonian orogenic event) such that it made contact with North America and Greenland during the Silurian and Early Devonian.
Industry:Earth science
A program to examine the status of marine ecosystems of the Pacific Ocean, Bering Sea and Chukchi Sea, and to assess their role in determining global climate. The objectives of BERPAC consist of the study of the biogeochemical cycles of contaminants, related oceanographical processes, and food-web interactions in the North Pacific waters that flow through the Bering and Chukchi Seas, including the study of the behavior of organic pollutants at the water/sediiment interface since sediments are source of the secondary pollution of ecosystems.
Industry:Earth science
A research project funded by the European Union whose aim is to understand the distribution of biogases in the surface water of European estuaries and to quantify related atmospheric exchanges.
Industry:Earth science
A method of flux correction that guarantees no long-term climate drift and reduces the other problems of flux correction. Fluxes are modified at the ocean-atmosphere interface but the correction is carried out on mean annual rather than monthly mean values, thus resulting in smaller and spatially smoother corrections. An interactive computation is also applied to reduce consistencies in the bias correction. This method was developed by J. Oberhuber at the DKRZ.
Industry:Earth science
A small sea centered in the Philippines at about 124° E and 9° S. It is surrounded by the islands of Mindanao to the southeast and Negros, Bohol and Leyte to the northwest. It is connected to the Sulu Sea to the west via a passage between Negros and Mindanao, the Visayan Sea to the north via the Tanon Strait, the Camotes Sea to the north via the Bohol Strait and a passage between Bohol and Leyte, and to the Leyte Gulf to the northeast via the Surigao Strait. Prominent geographic features include the islands of Siquijor and Camiguin and Sogod (in Leyte), Gingoog, Macajalar and Iligan (in Mindanao) Bays. This has also been called the Mindanao Sea.
Industry:Earth science
