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

More articles from Earth Sciences:

nachricht NASA sees quick development of Hurricane Dora
27.06.2017 | NASA/Goddard Space Flight Center

nachricht Collapse of the European ice sheet caused chaos
27.06.2017 | CAGE - Center for Arctic Gas Hydrate, Climate and Environment

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>