{"id":14806,"date":"2026-07-08T14:49:39","date_gmt":"2026-07-08T12:49:39","guid":{"rendered":"https:\/\/wp.unil.ch\/geoblog\/?p=14806"},"modified":"2026-07-08T14:50:22","modified_gmt":"2026-07-08T12:50:22","slug":"sediment-export-and-proglacial-area-change-at-outlet-glaciers-from-the-greenland-ice-sheet","status":"publish","type":"post","link":"https:\/\/wp.unil.ch\/geoblog\/2026\/07\/sediment-export-and-proglacial-area-change-at-outlet-glaciers-from-the-greenland-ice-sheet\/","title":{"rendered":"Sediment export and proglacial area change at outlet glaciers from the Greenland Ice Sheet"},"content":{"rendered":"<figure class=\"wp-block-post-featured-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1000\" height=\"750\" src=\"https:\/\/wp.unil.ch\/geoblog\/files\/2026\/07\/groenland.jpg\" class=\"attachment-post-thumbnail size-post-thumbnail wp-post-image\" alt=\"groenland\" style=\"object-fit:cover;\" srcset=\"https:\/\/wp.unil.ch\/geoblog\/files\/2026\/07\/groenland.jpg 1000w, https:\/\/wp.unil.ch\/geoblog\/files\/2026\/07\/groenland-300x225.jpg 300w, https:\/\/wp.unil.ch\/geoblog\/files\/2026\/07\/groenland-768x576.jpg 768w\" sizes=\"auto, (max-width: 1000px) 100vw, 1000px\" \/><\/figure>\n\n\n<div class=\"wp-block-group has-accent-5-background-color has-background has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"has-accent-5-background-color has-text-color has-background has-link-color wp-elements-fdac351bec18957a669404743113f6c1 wp-block-paragraph\" style=\"color:#212121;font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.49), 19px);\"><em>Th\u00e8se en sciences de l&rsquo;environnement, soutenue le 28 ao\u00fbt 2026 par Marjolein Gevers, rattach\u00e9e \u00e0 l&rsquo;Institut des dynamiques de la surface terrestre (IDYST) de la FGSE.<\/em><\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">La calotte glaciaire du Groenland fond \u00e0 mesure que le climat se r\u00e9chauffe. L\u2019eau de fonte de la calotte glaciaire transporte des s\u00e9diments (de petits fragments de roche et de sol) vers les rivi\u00e8res et les oc\u00e9ans situ\u00e9s en aval. Certains s\u00e9diments sont tr\u00e8s fins et restent en suspension dans l\u2019eau, tandis que des \u00e9l\u00e9ments plus gros comme le sable, le gravier et les roches se d\u00e9placent le long du lit de la rivi\u00e8re. Autour de Kalaallit Nunaat (Groenland), davantage de recherches ont \u00e9t\u00e9 men\u00e9es sur les s\u00e9diments fins, mais beaucoup moins sur les mat\u00e9riaux plus grossiers. On comprend \u00e9galement encore mal comment les zones situ\u00e9es devant les glaciers (zones proglaciaires) influencent le transport des s\u00e9diments vers l\u2019aval.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cette th\u00e8se \u00e9tudie les s\u00e9diments export\u00e9s par la calotte glaciaire du Groenland et la mani\u00e8re dont les terres situ\u00e9es devant les glaciers \u00e9voluent au fil du temps sous l\u2019influence de cette exportation de s\u00e9diments. La premi\u00e8re partie examine sept zones situ\u00e9es devant des glaciers dans le sud-ouest du Groenland entre environ 1985 et 2023 \u00e0 l\u2019aide de mod\u00e8les num\u00e9riques d\u2019\u00e9l\u00e9vation et des r\u00e9sultats de mod\u00e8les climatiques. La plupart de ces zones ont montr\u00e9 une \u00e9rosion, ce qui signifie que la surface du sol s\u2019est abaiss\u00e9e au fil du temps. Au glacier Leverett, une augmentation de l\u2019eau de fonte a \u00e9t\u00e9 associ\u00e9e \u00e0 l\u2019effondrement des berges de la rivi\u00e8re.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">La seconde partie \u00e9tudie le transport des s\u00e9diments au glacier Leverett pendant deux saisons estivales de fonte (2022 et 2023). Des mesures du d\u00e9bit de la rivi\u00e8re et de la sismologie environnementale (utilisation des vibrations du sol pour \u00e9tudier les processus environnementaux) ont \u00e9t\u00e9 utilis\u00e9es pour suivre \u00e0 la fois les s\u00e9diments fins et les s\u00e9diments plus grossiers se d\u00e9pla\u00e7ant le long du lit de la rivi\u00e8re. L\u2019\u00e9tude a montr\u00e9 que les s\u00e9diments fins et grossiers r\u00e9agissent diff\u00e9remment \u00e0 l\u2019augmentation de l\u2019eau de fonte. Les s\u00e9diments fins augmentent rapidement lorsque le d\u00e9bit d\u2019eau s\u2019\u00e9l\u00e8ve, tandis que les s\u00e9diments plus grossiers se d\u00e9placent plus lentement et deviennent plus importants plus tard dans la saison de fonte. Ces r\u00e9sultats montrent que mesurer uniquement les s\u00e9diments fins ne donne pas une image compl\u00e8te de la quantit\u00e9 de s\u00e9diments quittant la calotte glaciaire du Groenland.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>(DeepL translation to French)<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Th\u00e8se en sciences de l&rsquo;environnement<\/p>\n","protected":false},"author":47,"featured_media":14807,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"footnotes":"","_links_to":"","_links_to_target":""},"categories":[49465],"tags":[],"class_list":["post-14806","post","type-post","status-publish","format-standard","has-post-thumbnail","category-theses-soutenues"],"_links":{"self":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14806","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/users\/47"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/comments?post=14806"}],"version-history":[{"count":1,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14806\/revisions"}],"predecessor-version":[{"id":14809,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/posts\/14806\/revisions\/14809"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media\/14807"}],"wp:attachment":[{"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/media?parent=14806"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/categories?post=14806"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.unil.ch\/geoblog\/wp-json\/wp\/v2\/tags?post=14806"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}