NO JAVASCRIPT

This website requires JavaScript to function properly / Ce site a besoin de JavaScript pour fonctionner correctement

Aviso+
News
Image of the month
2003
Feb. 2003: Ocean currents

Ocean currents

Image of the Month - February 2003

Mean dynamic topography, i.e. oceanic relief corresponding to permanent ocean circulation, computed from hydrologic and drifting buoys, used jointly with altimetric measurements and Champ gravimetric satellite data (geoid model Eigen2). Arrows are proportional to current speed. This dynamic topography shows all the features of the general circulation. The ocean gyres and associated western boundary currents (e.g. Gulf Stream, Kuroshio, Brazil/Malvinas Confluence area) appear clearly on the map; so too does the Antarctic Circumpolar Current.

As at the eddy scale, global ocean circulation is made of "hills" and "valleys". Large scale ocean currents flow along the lines of equal dynamic topography (black arrows on the map). In the northern hemisphere, the flow is clockwise around the topography highs. In the southern hemisphere, the flow is counter-clockwise.

This mean circulation is not an immediate product of altimetry data. Those data give more the mean sea surface, which contains the marine geoid plus the sea elevation due to the mean oceanic circulation (see January 1999 Image of the Month "A glassy sea... of ridges and valleys"). So we have to combine altimetric data with others (in situ, gravimetric satellites...), to precisely determine the geoid, and by substracting it, compute the mean circulation.

Websites on this subject:

News

Search.
Front-page news.
Image of the month .
- 2024 .
- 2023 .
- 2022 .
- 2021 .
- 2020 .
- 2019 .
- 2018 .
- 2017 .
- 2016 .
- 2015 .
- 2014 .
- 2013 .
- 2012 .
- 2011 .
- 2010 .
- 2009 .
- 2008 .
- 2007 .
- 2006 .
- 2005 .
- 2004 .
- 2003 .
  - Dec. 2003: Warm waters.
  - Nov. 2003: Aral Sea: nothing new under the Sun.
  - Oct. 2003: Black Sea forecasting.
  - Sep. 2003: Scaling the waves.
  - Aug. 2003: Sea salt seen by altimeters.
  - Jul. 2003: Currents steered by gaps in the ridges.
  - Jun. 2003: Combining sensors.
  - May 2003: Flying tandem.
  - Apr. 2003: A looping current.
  - Mar. 2003: Africa's Great Lakes.
  - Feb. 2003: Ocean currents.
  - Jan. 2003: Altimetry and phytoplankton.
- 2002 .
- 2001 .
- 2000 .
- 1999 .
- 1998 .
Press review.
Operational news and status .
News from CTOH .
Events calendar.

Customizable homepage

This home page is composed of blocks called "widgets".

Rearrange the blocks with a "Click & Drop".

Hide a widget with the cross at the top right. Reset or add a widget with the "wrench" icon. The "User" and "Public" profiles offer a predefined organization.

All the modifications are automatically saved as cookies on your machine so as to enable you to have your own specific AVISO+.

Browsing menu and breadcrum trail

To ease your browsing through AVISO+, you can use at any time the main banner items with the interactive submenus or use the browsing menu on the left side of the screen (it is open by default). For more readiness of the page contents, you can fold and unfold the browsing menu by clicking on the tab. At any time you can know where you are thanks to the browsing menu or the breadcrum at the top of the page.