|
 List of all backgrounders
|
|
What is ...? How can I find out more about ...? Learn more about deep sea life, the mid-Atlantic ridge and marine ecology through our backgrounders, which are short articles about a topic. If you would like to know how it is to be on a research cruise, see the ship-to-shore section.
|
| Introduction to oceanography
Why study the oceans? "Oceanography is a diverse subject because it combines all the different sciences with the study of the ocean." (paraphrased from Joseph Valencic) |  | | |
| History of oceanography
The first deep-sea explorers were not scientists. They were fishermen, merchants, settlers and explorers of the 15th Century looking for new lands. These latter were the first “oceanographers” as they made meticulous maps of their travels. |  | | |
| The Secrets of the Deep
Only 200 years ago, it was generally assumed that the deep sea was void of life. The deep seas were comparable to deserts; it was believed that no animal life existed at depths greater than 400 – 500 m. Read about The Challenger Expedition (1872-76) and The Michael Sars Expedition of 1910. |  | | |
| |
|
| | Ghost catsharks
When ghost catsharks are born, the embryos have two rows of large tooth-like denticles on their back, which the scientists believe they use to hatch themselves out of the egg capsule. |  | | |
| White orange roughy
The orange roughy (Hoplostethus atlanticus) got its name because of its colouration and the special scales (scutes) formed along the belly thus making this part of the body resemble like an “armoured chest”. Scientists are fascinated of this fish, which might live until the age of 150 and can switch of its colour and become white! |  | | |
| Weird and wonderful deep sea fish
Ingvar Byrkjedal, a vertebrate curator at Bergen Museum, shared some fascinating deep sea specimens, some dating from nearly 100 years ago!
|  | | |
| Orange roughy story
Should we eat the Orange Roughy? Justifying MAR-ECO – the Orange Roughy experience. A medium sized fish with a firm, tasty white flesh, the Orange Roughy is a gourmet item on many restaurant menus. |  | | |
| Deep-sea fish
Deep-sea fishes: it may be that their life histories make them especially vulnerable to exploitation. |  | | |
| Seaturtles
Sea turtles undertake a tremendous migration that can cross the Atlantic ocean twice. |  | | |
| Cephalopods
Squids are cephalopods. The Cephalopods are a class of marine molluscs (soft-bodied animals) that include the octopus, squids, cuttlefish and nautilus. They have a well-developed head (cephalas), large brain and eyes that closely resemble vertebrate eyes in structure. The head is surrounded by prehensile tentacles |  | | |
| Cephalopods
Mike Vecchione, who is a MAR-ECO scientist and a cephalopod specialist presents a brief, popular description on cephalods. |  | | |
| Zooplankton
The fascinating oceanic zooplankton: conveyors of energy from the surface to the deep sea. |  | | |
| Facts about cephalopods
Some interesting facts about cephalopods from the FAQs on the Cephalopod Page. The Cephalopod Page (TCP) was created and is maintained by Dr. James B. Wood and is hosted by Dalhousie University and the University of Texas Medical Branch. |  | | |
| Fishing the ridge
Fisheries on the ridge: Prospects for fisheries on the seamounts, a russian study. Original paper by V.I.Vinnichenko, summarized by Elinor Bartle |  | | |
| Fish genetics
How can genetics be used to study fish populations?Rus Hoelzel and Halvor Knutsen have developed a project that uses genetic markers to identify population structure, levels of diversity within local populations and aspects of demographic history. |  | | |
| | Orange Roughy cartoon
To adapt life deeper than the light, deep-sea fishes has special features - as illustrated in the cartoon about Orange Roughy. |  | | |
| |
|
| | Deep-sea challenges
This is a backgrounder about physical oceanography. Deep is dangerous. It may be more dangerous for man to dive to the depths, than to go out in space. Learn more about these deep-sea challenges! |  |
| Pressure
Hydrostatic pressure is the most generally applicable factor with a constant increase of 10 atm per 100 m depth. Beginning with a depth of ca. 6000 m a change in faunal composition can be observed that is possibly related to pressure. |  |
| Temperature
Hydrostatic pressure is the most generally applicable factor with a constant increase of 10 atm per 100 m depth. Beginning with a depth of ca. 6000 m a change in faunal composition can be observed that is possibly related to pressure. |  |
| Light
Light is an important ecological factor that influences organisms significantly. Light is the primary source of energy intake in plants (primary production based on photosynthesis), it warms up air, bottoms, and water and allows direct absorption of heat by animals. Light facilitates the orientation in the environment and the recognition of food and mates. |  |
| Deep-sea structure
There are typical structural features that enable the ocean world to be divided into zones. Topographical zones, relating to the sea floor, and Bathymetric zones, relating to water depth. |  |
| Cool facts on ocean-currents
There are two main kinds of ocean currents, those driven by the wind and the earth's rotation that affect the surface waters, and those driven by density that affect the deeper waters. | |
| Ocean currents
The physical setting of the mid-Atlantic Ocean: Hydrodynamic modelling and satellite observations of regional watermasses and frontal zone features. |  |
| |
|
| | Deep-sea Structure
There are typical structural features that enable the ocean world to be divided into zones. Topographical zones, relating to the sea floor, and Bathymetric zones, relating to water depth.
|  |
| Plate tectonics
The earth's crust is constantly changing, and plate material is always being created and destroyed. As a result, the continents and oceans cannot ride atop the plates without being changed. |  |
| Seamounts
Seamounts are undersea mountains. They rise steeply from the sea floor and peak below sea level. Seamounts are found in all the world's oceans. By definition, they have an elevation of more than 1000 m. They may have very steep slopes with a gradient angle of up to 60° and their summit surface area is relatively small. Seamounts are usually relatively resistant to forces of erosion because they are generally formed in volcanic processes, and therefore mainly consist of hard substrates.
|  |
| |
|
| | MAR-ECO Technology
The choice of appropriate tools (technologies), procedures and strategies can make the difference between the success and failure of a research expedition. |  |
| | Research vessels: the G.O. Sars
"G.O. Sars" is one of the most advanced research vessels in the world and was handed over in May 2003. The vessel is used by the University of Bergen and the Institute of Marine Research.
|  |
| Technology tests onboard G.O. Sars
Application of modern technology is considered one of the most critical factors for success in the challenging investigations MAR-ECO is aiming for. Substantial effort has therefore been invested in fitting RV G.O. Sars properly. In the end of April 2004 a test cruise was carried out onboard RV G.O. Sars |  |
| Sampling equipment and technologies
List of sampling equipment and technologies used by RV G. O. Sars leg 1 and leg 2, and by MS Loran on leg 2 on the two months MAR-ECO expedition 2004.
|  |
| Longlining
During the last decade there has been a marked development of new and better fishing gear and technical solutions. Commercial technologies and know-how is also important for science, especially when focusing on areas that are out of the range of normal scientific equipment. |  |
| Submersibles
The remotely operated vehicle (ROV), the Aglantha, is used for marine biological and geological studies. The Aglantha was financed by Erna & Victor Hasselblads foundation. It was built and devlivered to UiB in 1998.
|  |
| The ROV Bathysaurus
Bathysaurus is a remotedly operated vehicle (ROV) especially designed for the main MAR-ECO cruise. Find out more about this advanced technology. |  |
| Acoustic
RV G.O. Sars represents a new generation of marine research vessels. With its vibration- and noise-damped diesel generators and its propellers driven by directcurrent motors, RV G.O. Sars is an extremely quiet vessel under way. It emits 99 percent less noise under water than conventional research vessels. |  |
| Taking oceanographical measurements: using a CTD
Just as taking a person’s temperature tells something about their physiological status, so can taking the temperature in the ocean tell us something about the ocean. Other parameters, such as salinity, water density etc reveal information about water movements and productivity. Oceanographers routinely measure a number of parameters in order to learn more about the ocean. |  |
| Currents in the North Atlantic
Extreme conditions have made deep-sea exploration nearly as challenging as space exploration, and nearly as infrequent. The deep waters of the ocean, surprisingly, do not provide a uniform environment where marine organisms are uniformly distributed. They are affected by a number of topographical features that are much more dramatic than any found on land. |  |
| |
|
| | Seawater
Seawater is a complex solution of many chemicals. Their concentration is, on average, 33-37 parts per thousand by weight. Ninety percent of this is common table salt, sodium chloride. | |
| Oxygen & salinity
Salinity in the deep sea varies mostly only slightly and ranges between 34.69 % in the Pacific and 35 % in the northern Atlantic. Only in the Red Sea and Mediterranean salinity is significantly higher with about 39 %. This influences also the adjacent seas, as the heavy surface water flows in and sinks to deeper levels. This may affect also the species composition in the NE Atlantic. | |
| |
|
|
|
|
|
