{"id":1024,"date":"2006-05-02T08:28:00","date_gmt":"2006-05-02T06:28:00","guid":{"rendered":"https:\/\/kids.esa.int\/space_radar_reveals_antarctic_rivers\/"},"modified":"2026-10-08T00:35:00","modified_gmt":"2026-10-07T22:35:00","slug":"space_radar_reveals_antarctic_rivers","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fr\/space_radar_reveals_antarctic_rivers\/","title":{"rendered":"Des rivi\u00e8res d\u00e9couvertes sous les glaciers de l'Antarctique"},"content":{"rendered":"<div class=\"lede\">\n<p>Les scientifiques savent depuis les ann\u00e9es 60 que de nombreux lacs se cachent sous les glaciers de l'Antarctique. Ils pensaient toutefois que ces \u00e9tendues d'eau \u00e9taient isol\u00e9es. Mais le satellite europ\u00e9en de t\u00e9l\u00e9d\u00e9tection ERS-2 semblerait r\u00e9v\u00e9ler que des rivi\u00e8res sub-glaciaires transportent des masses consid\u00e9rables d'eau d'un lac \u00e0 l'autre.<\/p>\n<\/div>\n<p>On doit cette d\u00e9couverte \u00e0 des chercheurs britanniques, qui analysaient les variations dans la hauteur de la calotte glaciaire. Les mesures extr\u00eamement pr\u00e9cises du radar ont r\u00e9v\u00e9l\u00e9 que la surface du glacier s'\u00e9tait affaiss\u00e9e d'environ trois m\u00e8tres au-dessus d'un lac. Par contre, \u00e0 quelques deux cent quatre-vingt dix kilom\u00e8tres de l\u00e0, au-dessus de deux lacs distincts, le glacier s'\u00e9tait soulev\u00e9.<\/p>\n<p>La seule explication possible est qu'une rivi\u00e8re aussi large que la Tamise coule sous les 4 kilom\u00e8tres d'\u00e9paisseur de la calotte glaciaire. En 16 mois, environ 1,8 km3 d'eau a emprunt\u00e9 un tunnel creus\u00e9 \u00e0 l'int\u00e9rieur de la glace.<\/p>\n<p>\"Ces nouvelles donn\u00e9es montrent que les lacs sub-glaciaires 'sautent' parfois comme des bouchons de champagne, lib\u00e9rant des inondations qui se propagent sur de tr\u00e8s grandes distances\", a expliqu\u00e9 le professeur Duncan Wingham de l'University College London (UCL).<\/p>\n<p>\"Cette d\u00e9couverte pose un probl\u00e8me de taille : le forage du glacier jusqu'aux lacs pourrait les contaminer avec de nouveaux microbes,\" a ajout\u00e9 le professeur Wingham. \"Nos donn\u00e9es indiquent que la contamination ne serait pas limit\u00e9e \u00e0 un lac, mais qu'elle se propagerait \u00e0 tout le r\u00e9seau des cours d'eau.<\/p>\n<p>\"Nous pensions que ces lacs \u00e9taient aussi isol\u00e9s que des laboratoires de biologie. Aujourd'hui, nous devons tout remettre en question.\"<\/p>","protected":false},"excerpt":{"rendered":"<p>Scientists have known for decades about many huge lakes that hide beneath the frozen wastes of Antarctica. However, it has usually been assumed that the lakes were isolated. Now a [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"esa_banner_image":"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2006\/04\/the_dry_valleys_in_coastal_east_antarctica2\/17910935-2-eng-GB\/The_Dry_Valleys_in_coastal_East_Antarctica.jpg","esa_banner_description":"The Dry Valleys in coastal East Antarctica","esa_banner_credit":"David Sugden, Edinburgh University","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2006\/04\/The_Dry_Valleys_in_coastal_East_Antarctica2","esa_external_url":"","esa_external_new_window":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":true},"categories":[42,10,66],"tags":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-1024","post","type-post","status-publish","format-standard","hentry","category-earth","category-learn","category-water-world"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1024","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/comments?post=1024"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1024\/revisions"}],"predecessor-version":[{"id":2167,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/posts\/1024\/revisions\/2167"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/media?parent=1024"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/categories?post=1024"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/tags?post=1024"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/panel?post=1024"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/language?post=1024"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/age?post=1024"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/duration?post=1024"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/resource_type?post=1024"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/audience?post=1024"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fr\/wp-json\/wp\/v2\/wf_post_folders?post=1024"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}