{"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\/fi\/space_radar_reveals_antarctic_rivers\/","title":{"rendered":"Avaruustutka paljastaa Etel\u00e4mantereen joet"},"content":{"rendered":"
\n

Tutkijat ovat jo vuosikymmenten ajan tienneet, ett\u00e4 Etel\u00e4mantereen j\u00e4\u00e4peitteen alla piilee lukuisia valtavia j\u00e4rvi\u00e4. Yleens\u00e4 on kuitenkin oletettu, ett\u00e4 n\u00e4m\u00e4 j\u00e4rvet ovat erillisi\u00e4 toisistaan. Nyt eurooppalainen ERS-2-niminen tutkasatelliitti on osoittanut, ett\u00e4 j\u00e4\u00e4n alla virtaavat joet saattavat siirt\u00e4\u00e4 valtavia m\u00e4\u00e4ri\u00e4 tulvavett\u00e4 j\u00e4rvest\u00e4 toiseen.<\/p>\n<\/div>\n

L\u00f6yd\u00f6n tekiv\u00e4t brittil\u00e4iset tutkijat, jotka analysoivat j\u00e4\u00e4peitteen pinnan korkeuden muutoksia. Eritt\u00e4in tarkat tutkamittaukset pinnan korkeudesta paljastivat, ett\u00e4 yhden j\u00e4rven yl\u00e4puolella oleva j\u00e4\u00e4 oli vajoanut noin kolme metri\u00e4. 290 kilometrin p\u00e4\u00e4ss\u00e4, kahden eri j\u00e4\u00e4tik\u00f6n alla sijaitsevan j\u00e4rven yl\u00e4puolella, j\u00e4\u00e4 oli pullistunut yl\u00f6sp\u00e4in.<\/p>\n

N\u00e4m\u00e4 muutokset j\u00e4\u00e4n korkeudessa voidaan selitt\u00e4\u00e4 sill\u00e4, ett\u00e4 4 kilometrin paksuisen j\u00e4\u00e4peitteen alla virtaisi Lontoon Thamesin kaltainen suuri joki. 16 kuukauden aikana noin 1,8 kuutiokilometri\u00e4 vett\u00e4 ry\u00f6ppyi kiinte\u00e4\u00e4n j\u00e4\u00e4h\u00e4n kaivettua tunnelia pitkin<\/p>\n

\u201cN\u00e4m\u00e4 uudet tiedot osoittavat, ett\u00e4 j\u00e4\u00e4peitteen alla olevat j\u00e4rvet purkautuvat silloin t\u00e4ll\u00f6in kuin samppanjakorkit ja vapauttavat tulvavirtoja, jotka kulkevat hyvin pitki\u00e4 matkoja\u201d, sanoi professori Duncan Wingham (University College, Lontoo).<\/p>\n

\u201cSuuri huolenaihe on ollut se, ett\u00e4 poraamalla j\u00e4rviin saataisiin uusia mikrobeja\u201d, sanoi professori Wingham. \u201cTietomme osoittavat, ett\u00e4 mahdollinen saastuminen ei rajoitu yhteen j\u00e4rveen, vaan levi\u00e4\u00e4 ajan my\u00f6t\u00e4 koko jokiverkoston pituudelle.\u201d.<\/p>\n

\u201cOlimme pit\u00e4neet n\u00e4it\u00e4 j\u00e4rvi\u00e4 erillisin\u00e4 biologisina laboratorioina. Nyt meid\u00e4n on mietitt\u00e4v\u00e4 asiaa uudelleen.\u201d<\/p>","protected":false},"excerpt":{"rendered":"

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 […]<\/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\/fi\/wp-json\/wp\/v2\/posts\/1024","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=1024"}],"version-history":[{"count":1,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/1024\/revisions"}],"predecessor-version":[{"id":2167,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/posts\/1024\/revisions\/2167"}],"wp:attachment":[{"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/media?parent=1024"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/categories?post=1024"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/tags?post=1024"},{"taxonomy":"panel","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/panel?post=1024"},{"taxonomy":"language","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/language?post=1024"},{"taxonomy":"age","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/age?post=1024"},{"taxonomy":"duration","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/duration?post=1024"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/resource_type?post=1024"},{"taxonomy":"audience","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/audience?post=1024"},{"taxonomy":"wf_post_folders","embeddable":true,"href":"https:\/\/kids.esa.int\/fi\/wp-json\/wp\/v2\/wf_post_folders?post=1024"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}