{"id":435,"date":"2017-07-17T10:04:00","date_gmt":"2017-07-17T08:04:00","guid":{"rendered":"https:\/\/kids.esa.int\/gigantic_iceberg_now_floating_free\/"},"modified":"2026-10-08T00:28:10","modified_gmt":"2026-10-07T22:28:10","slug":"gigantic_iceberg_now_floating_free","status":"publish","type":"post","link":"https:\/\/kids.esa.int\/fi\/gigantic_iceberg_now_floating_free\/","title":{"rendered":"Valtava j\u00e4\u00e4vuori kelluu nyt vapaasti"},"content":{"rendered":"<div class=\"lede\">\n<p>Viime kuukausien aikana suuri halkeama on leikannut l\u00e4pi valtavan j\u00e4\u00e4lohkareen Etel\u00e4mantereella. ESA:n Sentinel-1-satelliitit ovat nyt havainneet, ett\u00e4 j\u00e4\u00e4 on irronnut kokonaan, muodostaen yhden suurimmista koskaan havaituista j\u00e4\u00e4vuorista.<\/p>\n<\/div>\n<figure class=\"wp-block-image size-large\" data-width=\"849\" data-credit=\"contains modified Copernicus Sentinel data (2017), processed by ESA, CC BY-SA 3.0 IGO\" data-detail-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2017\/07\/Ice_crack_seen_by_Sentinel-2A\" data-licence=\"CC BY-SA 3.0 IGO or ESA Standard Licence\" data-licence-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\"><img decoding=\"async\" loading=\"lazy\" style=\"max-width:100%;height:auto\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2017\/07\/ice_crack_seen_by_sentinel-2a\/17906200-2-eng-GB\/Ice_crack_seen_by_Sentinel-2A.jpg\" alt=\"Ice crack seen by Sentinel-2A\"><figcaption>Sentinel-2A:n havaitsema j\u00e4\u00e4halkeama<\/figcaption><\/figure>\n<p>Halkeama ilmestyi itse asiassa jo useita vuosia sitten, mutta aluksi se ei kasvanut juurikaan. Tilanne muuttui vuoden 2016 alussa, kun halkeama alkoi pidenty\u00e4. Pelk\u00e4st\u00e4\u00e4n tammikuussa 2017 se kasvoi 20 km ja saavutti kokonaispituuden 175 km. Hein\u00e4kuun 2017 alussa halkeaman k\u00e4rjen ja meren v\u00e4lill\u00e4 oli en\u00e4\u00e4 muutama kilometri. Siit\u00e4 l\u00e4htien tutkijat ovat odottaneet, ett\u00e4 halkeama saavuttaa meren ja irrottaa siten valtavan j\u00e4\u00e4vuoren Antarktikasta.<\/p>\n<p>Valitettavasti Etel\u00e4mantereella on alkamassa pime\u00e4t talvikuukaudet, jolloin valoa on v\u00e4h\u00e4n ja huono s\u00e4\u00e4 on yleist\u00e4, mik\u00e4 vaikeuttaa havainnointia jopa satelliittien avulla. T\u00e4m\u00e4n ongelman ratkaisemiseksi MIDAS-projektin tutkijat \u2013 brittil\u00e4isen Swansea-yliopiston johtama Etel\u00e4mantereen tutkimusryhm\u00e4 \u2013 k\u00e4yttiv\u00e4t Sentinel-satelliittien tutkakuvausta l\u00e4p\u00e4ist\u00e4kseen pimeyden ja pilvet.<\/p>\n<figure class=\"wp-block-image size-large\" data-width=\"1500\" data-credit=\"P. Nyquist\" data-detail-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2017\/07\/Trekking_out_for_CryoSat\" data-licence=\"ESA Standard Licence\" data-licence-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\"><img decoding=\"async\" loading=\"lazy\" style=\"max-width:100%;height:auto\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2017\/07\/trekking_out_for_cryosat\/17900569-2-eng-GB\/Trekking_out_for_CryoSat.jpg\" alt=\"Trekking out for CryoSat\"><figcaption>Retki CryoSat-satelliitin luo<\/figcaption><\/figure>\n<p>Lis\u00e4ksi tutkijat ovat seuranneet tilanteen kehittymist\u00e4 toisen ESA:n satelliitin, CryoSat-satelliitin, avulla. CryoSatissa on laite, jota kutsutaan tutka-korkeusmittariksi ja joka pystyy mittaamaan j\u00e4\u00e4n korkeutta ja paksuutta. Sen avulla saimme selville, ett\u00e4 halkeama oli kymmeni\u00e4 metrej\u00e4 syv\u00e4 eik\u00e4 kyseess\u00e4 ollut pelkk\u00e4 pinnallinen halkeama.<\/p>\n<p>T\u00e4m\u00e4n uuden j\u00e4ttim\u00e4isen j\u00e4\u00e4vuoren pinta-ala on noin 6 000 neli\u00f6kilometri\u00e4, ja se painaa yli miljoona miljoonaa tonnia! On vaikea ennustaa, mit\u00e4 sille seuraavaksi tapahtuu. Se saattaa pysy\u00e4 kellumassa alueella monien vuosien ajan. Tai se saattaa hajota pienemmiksi j\u00e4\u00e4vuoriksi, jotka voivat ajautua pohjoiseen l\u00e4mpim\u00e4mpiin vesiin, joissa j\u00e4\u00e4 sulaa.<\/p>\n<figure class=\"wp-block-image size-large\" data-width=\"1500\" data-credit=\"ESA\u2013Pierre\" data-detail-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2017\/07\/Artist_s_impression_of_Sentinel-1B\" data-licence=\"ESA Standard Licence\" data-licence-url=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\"><img decoding=\"async\" loading=\"lazy\" style=\"max-width:100%;height:auto\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2017\/07\/artist_s_impression_of_sentinel-1b\/17899311-2-eng-GB\/Artist_s_impression_of_Sentinel-1B.jpg\" alt=\"Artist\u2019s impression of Sentinel-1B\"><figcaption>Taiteilijan n\u00e4kemys Sentinel-1B:st\u00e4<\/figcaption><\/figure>\n<p>Antarktiksen menett\u00e4ess\u00e4 n\u00e4in suuren j\u00e4\u00e4palasen voi aiheutua ongelmia. Kun vastaavia tapahtumia on aiemmin sattunut, se on nopeuttanut j\u00e4\u00e4tik\u00f6iden virtausta meriin, mik\u00e4 on vaikuttanut maapallon merenpinnan nousuun.<\/p>\n<p>Hyv\u00e4 uutinen on, ett\u00e4 ESA:n satelliittien ansiosta voimme seurata ajantasaisesti, miten planeettamme muuttuu, etenkin sellaisissa paikoissa, joihin on eritt\u00e4in vaikea p\u00e4\u00e4st\u00e4, kuten Antarktikalla. Mit\u00e4 enemm\u00e4n tietoa meill\u00e4 on, sit\u00e4 paremmin voimme suojella planeettaamme ja sill\u00e4 el\u00e4v\u00e4\u00e4 el\u00e4m\u00e4\u00e4!<\/p>\n<p><b>Mielenkiintoinen fakta:<\/b> J\u00e4\u00e4vuori sis\u00e4lt\u00e4\u00e4 suunnilleen saman m\u00e4\u00e4r\u00e4n vett\u00e4 kuin Pohjois-Amerikassa sijaitseva Ontarionj\u00e4rvi!<\/p>","protected":false},"excerpt":{"rendered":"<p>For the last few months a large crack has been cutting across a vast chunk of ice in Antarctica. ESA\u2019s Sentinel-1 satellites have now seen the ice completely break away, [&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\/2017\/07\/larsen_c_breaks2\/17881808-2-eng-GB\/Larsen_C_breaks.jpg","esa_banner_description":"Larsen C breaks","esa_banner_credit":"contains modified Copernicus Sentinel data (2017), processed by ESA, CC BY-SA 3.0 IGO","esa_banner_licence":"CC BY-SA 3.0 IGO or ESA Standard Licence","esa_banner_detail_url":"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2017\/07\/Larsen_C_breaks2","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":[26],"tags":[],"panel":[],"language":[],"age":[],"duration":[],"resource_type":[],"audience":[],"wf_post_folders":[],"class_list":["post-435","post","type-post","status-publish","format-standard","hentry","category-news"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/435","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/comments?post=435"}],"version-history":[{"count":4,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/435\/revisions"}],"predecessor-version":[{"id":4471,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/435\/revisions\/4471"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=435"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=435"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=435"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=435"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=435"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=435"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=435"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=435"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=435"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=435"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}