{"id":718,"date":"2012-03-27T12:48:00","date_gmt":"2012-03-27T10:48:00","guid":{"rendered":"https:\/\/kids.esa.int\/keeping_an_eye_from_the_sky_on_volcanoes\/"},"modified":"2026-10-08T00:31:30","modified_gmt":"2026-10-07T22:31:30","slug":"keeping_an_eye_from_the_sky_on_volcanoes","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/da\/keeping_an_eye_from_the_sky_on_volcanoes\/","title":{"rendered":"At holde \u00f8je med vulkaner \u2013 set fra luften"},"content":{"rendered":"
\n

Udbruddet af vulkanen Eyjafjallaj\u00f6kull p\u00e5 Island i 2010 viste os, at vulkanudbrud kan have alvorlige konsekvenser, der rammer tusindvis af mennesker. Derfor er satellitter, der overv\u00e5ger vulkaner, yderst vigtige.<\/p>\n<\/div>\n

Desv\u00e6rre overv\u00e5ges de fleste vulkaner rundt om i verden ikke s\u00e6rlig godt \u2013 hvis de overhovedet overv\u00e5ges! En unders\u00f8gelse i tidsskriftet *Science* viste, at ud af 440 aktive vulkaner i verden er 384 kun overv\u00e5get i meget begr\u00e6nset omfang eller slet ikke. Af disse vulkaner blev 65 identificeret som udg\u00f8rende en alvorlig risiko for store befolkningsgrupper.<\/p>\n

\"Alutu
Alutu-vulkanen<\/figcaption><\/figure>\n

Jordobservationssatellitter, s\u00e5som ESA\u2019s Envisat, kan ved hj\u00e6lp af interferometrisk syntetisk aperturradar (InSAR) registrere forandringer p\u00e5 vulkaner, der ikke overv\u00e5ges. InSAR er en fjernm\u00e5lingsteknik, hvor man tager to eller flere radarbilleder af det samme omr\u00e5de og kombinerer dem. Derved kan vi se, om der er sket \u00e6ndringer i overfladen mellem det tidspunkt, hvor det f\u00f8rste og det andet billede blev taget. Disse \u00e6ndringer ses som regnbuefarvede m\u00f8nstre p\u00e5 det nye sammensatte billede.<\/p>\n

P\u00e5 baggrund af disse satellitobservationer ved man nu, at mange vulkaner, som man tidligere troede var inaktive, viser tegn p\u00e5 aktivitet.<\/p>\n

De nye Sentinel-satellitter forventes at indsamle data over alle landmasser, herunder vulkaner, hver sjette dag i de n\u00e6ste 20 \u00e5r. Den f\u00f8rste af disse satellitter vil blive opsendt n\u00e6ste \u00e5r, i 2013. Dette vil bidrage til overv\u00e5gningen af mange af verdens vulkaner.<\/p>\n

Ved hj\u00e6lp af satellitter fors\u00f8ger forskerne at forst\u00e5, hvorn\u00e5r vulkansk aktivitet vil f\u00f8re til udbrud. Satellitdata kan ogs\u00e5 hj\u00e6lpe lande med at udarbejde evakueringsplaner for mennesker, der bor i n\u00e6rheden af vulkaner, og hvis liv kan v\u00e6re i fare.<\/p>","protected":false},"excerpt":{"rendered":"

The eruption of the Eyjafjallaj\u00f6kull volcano in Iceland in 2010 showed us that volcanic eruptions can have major consequences, affecting thousands of people. That is why satellites that keep an […]<\/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\/2011\/06\/puzzle_-_volcanoes2\/17895497-2-eng-GB\/Puzzle_-_Volcanoes.jpg","esa_banner_description":"","esa_banner_credit":"ESA","esa_banner_licence":"ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2011\/06\/Puzzle_-_Volcanoes2","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":[42,10,59],"tags":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-718","post","type-post","status-publish","format-standard","hentry","category-earth","category-learn","category-natural-disasters"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/718","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/comments?post=718"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/718\/revisions"}],"predecessor-version":[{"id":4646,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/posts\/718\/revisions\/4646"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/media?parent=718"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/categories?post=718"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/tags?post=718"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/panel?post=718"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/language?post=718"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/age?post=718"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/duration?post=718"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/resource_type?post=718"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/audience?post=718"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/da\/wp-json\/wp\/v2\/wf_post_folders?post=718"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}