Mobile version

Arctic sea ice shrinks and thins

Image of the Month - February 2010

Map of the sea ice thickness anomaly for the 2007/2008 winter (2007/2008 winter thickness minus the average thickness for the 2002/2008 winters). In some areas (e.g. North Chukchi Plateau (A), Canada Basin (B) and Beaufort Sea (C)), the ice thinned, up to 1.5 m or more. The grey areas are where there are no available data (especially higher than 81.5°, the maximum latitude for Envisat). (Credits Centre for Polar Observation and Modelling)

 
Arctic is one of the most sensitive regions to climate change. The sea ice is especially sensitive, and its vanishing could have serious impacts.

September 2007 saw a record minimum in Arctic sea ice extend -- which is to say, the Arctic sea ice was never observed covering so small an area than that year. This was measured by many different satellites (altimetric ones among others). The ice thickness has also changed following this episode. Envisat altimeter enabled to estimate this thinning, of 0.26 m with respect to the 2002-2008 average overall, and up to 0.49 m for the Western basin.

Altimetry satellites such as ERS and Envisat (Esa), which go up to 81.5° North and South, provide measurements of the sea ice height with respect to the water height (the "freeboard"). Since the ice is floating, taking into account ice and snow density, and following Archimedes principle, sea ice thickness can be computed from these measurements of ice freeboard. It must be noted, however, that ice thinner than 0.5 m is not measured by such a method.

The Cryosat-2 satellite, to be launch on February 25 2010, will provide much more precise information on such measurements due to its enhanced altimeter design and  high latitude orbit (up to 88°North and South).

See also:

Websites on this subject:

References:

  • Giles, K. A., S. W. Laxon, and A. L. Ridout (2008), Circumpolar thinning of Arctic sea ice following the 2007 record ice extent minimum, Geophys. Res. Lett., 35, L22502, doi:10.1029/2008GL035710

EnglishFrançaisEspañol
Rss feedsContactSitemapPartnersFAQGlossaryLexiconMobile
You must enable cookies in your browser preferences to save the modifications
You are using an older version of Internet Explorer, please update to take full advantage of Aviso+ features

Customize the home page

View all widgets
Reduce display
Public profile
User profile

Select/Deselect widgets

Discover AVISO+

Customizable home, reading tools, products search guide, etc.. Discover step by step the features of the new site AVISO+.

Customizable homepage

The new 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+.

Reading tools

Ease your reading by choosing the page background colour (black/white) and/or by modifying the font size.

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.

Products search guide

The first submenu of the "Data" banner item leads you to a new search form enabling you to find quickier the product that suits your needs. The list of results is updated according to your selection criteria.

AVISO+ Multimedia

The first submenu of the "Multimedia" banner item leads you to AVISO+ collections of images and videos linked to altimetry and its applications. Have a nice visit!