Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Indian eddies supply Atlantic Ocean with warm water

11.10.2005


Water from the Indian Ocean does not reach the South Atlantic Ocean continuously, but in separate packages. These are called Agulhas eddies, after the current along the east coast of Southern Africa where they originate from. Dutch researcher Astrid van Veldhoven characterised the fate of these rapidly rotating, three hundred kilometre wide and five kilometres deep, warm eddies during their journey to the Atlantic Ocean.



Over the past four years, the Royal Netherlands Institute for Sea Research (NIOZ) on Texel, in partnership with Utrecht University and the University of Cape Town, has carried out a large NWO-funded project into the Agulhas eddies, which transport seawater from the Indian Ocean to the South Atlantic Ocean. During this project the NIOZ research vessel ’Pelagia’ and the University of Cape Town’s research vessel ’Agulhas’ were remotely navigated by the Utrecht researchers, who interpreted satellite images from behind their computers. Satellite images revealed that the warm Agulhas eddies rose up as small hills above the Atlantic Ocean with a maximum height of about one metre.

Moreover, Van Veldhoven visited the eddies on three occasions onboard the research vessel. The Agulhas eddies turned out to be large warm rings of water from the Indian Ocean with a diameter of about 300 kilometres within which the water sometimes rotated at a speed of more than 3.6 kilometres per hour in an anticlockwise direction. To everyone’s surprise the eddy was found to stretch from the ocean surface right down to the ocean floor at a depth of some five kilometres; it therefore has a volume of about 350,000 cubic kilometres.


On the ocean surface, young eddies are at most 5 degrees Celsius warmer than the surrounding Atlantic Ocean. Due to their enormous volume, the eddies import considerable quantities of heat into the Atlantic Ocean.

Van Veldhoven carried out a detailed study of how these enormous eddies transformed, rotated increasingly slowly, and as a result of this gradually released their heat and salt into the surrounding cold Atlantic Ocean and into the atmosphere. The eddies only completely subside when they are halfway to South America.

The knowledge acquired from this research will be used to improve computer models of the global ocean circulation. Such models are necessary for improved predictions of climate change and the degree of global warming due to the greenhouse effect.

Astrid van Veldhoven’s research was funded by NWO.

Dr Astrid van Veldhoven | alfa
Further information:
http://www.nwo.nl/nwohome.nsf/pages/NWOP_6GMGCA_Eng

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: It’s All in the Mix: Jülich Researchers are Developing Fast-Charging Solid-State Batteries

There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.

The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Quantum bugs, meet your new swatter

20.08.2018 | Information Technology

A novel synthetic antibody enables conditional “protein knockdown” in vertebrates

20.08.2018 | Life Sciences

Metamolds: Molding a mold

20.08.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>