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[o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Logg inn</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Sider for utlogga bidragsytarar <a href="/wiki/Hjelp:Introduksjon" aria-label="Lær meir om redigering"><span>lær meir</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Spesial:Bidraga_mine" title="Liste over endringar gjorde frå denne IP-adressa [y]" accesskey="y"><span>Bidrag</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Spesial:Diskusjonssida_mi" title="Diskusjon om endringar gjorde av denne ip-adressa [n]" accesskey="n"><span>Diskusjon</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Nettstad"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Innhald" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Innhald</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">flytt til sidefeltet</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">gøym</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">Byrjinga</div> </a> </li> <li id="toc-Målingar_av_sjøis" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Målingar_av_sjøis"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Målingar av sjøis</span> </div> </a> <button aria-controls="toc-Målingar_av_sjøis-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Vis/skjul underseksjonen Målingar av sjøis</span> </button> <ul id="toc-Målingar_av_sjøis-sublist" class="vector-toc-list"> <li id="toc-Historisk_rekord_i_Arktis_i_2007" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Historisk_rekord_i_Arktis_i_2007"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Historisk rekord i Arktis i 2007</span> </div> </a> <ul id="toc-Historisk_rekord_i_Arktis_i_2007-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Årsaker_til_redusert_sjøis" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Årsaker_til_redusert_sjøis"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Årsaker til redusert sjøis</span> </div> </a> <ul id="toc-Årsaker_til_redusert_sjøis-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Nokre_effektar_av_sjøisen" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Nokre_effektar_av_sjøisen"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Nokre effektar av sjøisen</span> </div> </a> <ul id="toc-Nokre_effektar_av_sjøisen-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Kjelder" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Kjelder"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Kjelder</span> </div> </a> <ul id="toc-Kjelder-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Innhald" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Vis/skjul innhaldslista" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Vis/skjul innhaldslista</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Sjøis</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Gå til ein artikkel på eit anna språk. Tilgjengeleg på 53 språk" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-53" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">53 språk</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Sj%C3%B8is" title="Sjøis – norsk bokmål" lang="nb" hreflang="nb" data-title="Sjøis" data-language-autonym="Norsk bokmål" data-language-local-name="norsk bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Havsis" title="Havsis – svensk" lang="sv" hreflang="sv" data-title="Havsis" data-language-autonym="Svenska" data-language-local-name="svensk" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Havis" title="Havis – dansk" lang="da" hreflang="da" data-title="Havis" data-language-autonym="Dansk" data-language-local-name="dansk" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%AC%D9%84%D9%8A%D8%AF_%D8%A8%D8%AD%D8%B1%D9%8A" title="جليد بحري – arabisk" lang="ar" hreflang="ar" data-title="جليد بحري" data-language-autonym="العربية" data-language-local-name="arabisk" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Banquisa" title="Banquisa – asturisk" lang="ast" hreflang="ast" data-title="Banquisa" data-language-autonym="Asturianu" data-language-local-name="asturisk" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9C%D0%B0%D1%80%D1%81%D0%BA%D1%96_%D0%BB%D1%91%D0%B4" title="Марскі лёд – belarusisk (klassisk ortografi)" lang="be-tarask" hreflang="be-tarask" data-title="Марскі лёд" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="belarusisk (klassisk ortografi)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9C%D0%BE%D1%80%D1%81%D0%BA%D0%B8_%D0%BB%D0%B5%D0%B4" title="Морски лед – bulgarsk" lang="bg" hreflang="bg" data-title="Морски лед" data-language-autonym="Български" data-language-local-name="bulgarsk" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Morskorneg" title="Morskorneg – bretonsk" lang="br" hreflang="br" data-title="Morskorneg" data-language-autonym="Brezhoneg" data-language-local-name="bretonsk" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Banquisa" title="Banquisa – katalansk" lang="ca" hreflang="ca" data-title="Banquisa" data-language-autonym="Català" data-language-local-name="katalansk" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%A2%D0%B8%D0%BD%C4%95%D1%81_%D0%BF%C4%83%D1%80%C4%95" title="Тинĕс пăрĕ – tsjuvansk" lang="cv" hreflang="cv" data-title="Тинĕс пăрĕ" data-language-autonym="Чӑвашла" data-language-local-name="tsjuvansk" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Mo%C5%99sk%C3%BD_led" title="Mořský led – tsjekkisk" lang="cs" hreflang="cs" data-title="Mořský led" data-language-autonym="Čeština" data-language-local-name="tsjekkisk" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Meereis" title="Meereis – tysk" lang="de" hreflang="de" data-title="Meereis" data-language-autonym="Deutsch" data-language-local-name="tysk" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Merej%C3%A4%C3%A4" title="Merejää – estisk" lang="et" hreflang="et" data-title="Merejää" data-language-autonym="Eesti" data-language-local-name="estisk" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Sea_ice" title="Sea ice – engelsk" lang="en" hreflang="en" data-title="Sea ice" data-language-autonym="English" data-language-local-name="engelsk" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Banquisa" title="Banquisa – spansk" lang="es" hreflang="es" data-title="Banquisa" data-language-autonym="Español" data-language-local-name="spansk" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Flosglacio" title="Flosglacio – esperanto" lang="eo" hreflang="eo" data-title="Flosglacio" data-language-autonym="Esperanto" data-language-local-name="esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Bankisa" title="Bankisa – baskisk" lang="eu" hreflang="eu" data-title="Bankisa" data-language-autonym="Euskara" data-language-local-name="baskisk" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%AF%D8%B1%DB%8C%D8%A7%DB%8C%D8%AE" title="دریایخ – persisk" lang="fa" hreflang="fa" data-title="دریایخ" data-language-autonym="فارسی" data-language-local-name="persisk" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Glace_de_mer" title="Glace de mer – fransk" lang="fr" hreflang="fr" data-title="Glace de mer" data-language-autonym="Français" data-language-local-name="fransk" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Oighear_mara" title="Oighear mara – irsk" lang="ga" hreflang="ga" data-title="Oighear mara" data-language-autonym="Gaeilge" data-language-local-name="irsk" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Banquisa" title="Banquisa – galisisk" lang="gl" hreflang="gl" data-title="Banquisa" data-language-autonym="Galego" data-language-local-name="galisisk" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%ED%95%B4%EB%B9%99" title="해빙 – koreansk" lang="ko" hreflang="ko" data-title="해빙" data-language-autonym="한국어" data-language-local-name="koreansk" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%B8%E0%A4%AE%E0%A5%81%E0%A4%A6%E0%A5%8D%E0%A4%B0%E0%A5%80_%E0%A4%AC%E0%A4%B0%E0%A5%8D%E0%A4%AB%E0%A4%BC" title="समुद्री बर्फ़ – hindi" lang="hi" hreflang="hi" data-title="समुद्री बर्फ़" data-language-autonym="हिन्दी" data-language-local-name="hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Es_laut" title="Es laut – indonesisk" lang="id" hreflang="id" data-title="Es laut" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonesisk" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Haf%C3%ADs" title="Hafís – islandsk" lang="is" hreflang="is" data-title="Hafís" data-language-autonym="Íslenska" data-language-local-name="islandsk" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Banchisa" title="Banchisa – italiensk" lang="it" hreflang="it" data-title="Banchisa" data-language-autonym="Italiano" data-language-local-name="italiensk" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A7%D7%A8%D7%97_%D7%99%D7%9D" title="קרח ים – hebraisk" lang="he" hreflang="he" data-title="קרח ים" data-language-autonym="עברית" data-language-local-name="hebraisk" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kbp mw-list-item"><a href="https://kbp.wikipedia.org/wiki/Pa%C5%8Bgiizi" title="Paŋgiizi – kabiye" lang="kbp" hreflang="kbp" data-title="Paŋgiizi" data-language-autonym="Kabɩyɛ" data-language-local-name="kabiye" class="interlanguage-link-target"><span>Kabɩyɛ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%96%E1%83%A6%E1%83%95%E1%83%98%E1%83%A1_%E1%83%A7%E1%83%98%E1%83%9C%E1%83%A3%E1%83%9A%E1%83%98" title="ზღვის ყინული – georgisk" lang="ka" hreflang="ka" data-title="ზღვის ყინული" data-language-autonym="ქართული" data-language-local-name="georgisk" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9D%D0%B8%D0%BB%D0%B0%D1%81" title="Нилас – kasakhisk" lang="kk" hreflang="kk" data-title="Нилас" data-language-autonym="Қазақша" data-language-local-name="kasakhisk" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-kw mw-list-item"><a href="https://kw.wikipedia.org/wiki/Morrew" title="Morrew – kornisk" lang="kw" hreflang="kw" data-title="Morrew" data-language-autonym="Kernowek" data-language-local-name="kornisk" class="interlanguage-link-target"><span>Kernowek</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Glacies_marina" title="Glacies marina – latin" lang="la" hreflang="la" data-title="Glacies marina" data-language-autonym="Latina" data-language-local-name="latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Zie%C3%AB-ies" title="Zieë-ies – limburgsk" lang="li" hreflang="li" data-title="Zieë-ies" data-language-autonym="Limburgs" data-language-local-name="limburgsk" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9C%D0%BE%D1%80%D1%81%D0%BA%D0%B8_%D0%BC%D1%80%D0%B0%D0%B7" title="Морски мраз – makedonsk" lang="mk" hreflang="mk" data-title="Морски мраз" data-language-autonym="Македонски" data-language-local-name="makedonsk" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Air_batu_laut" title="Air batu laut – malayisk" lang="ms" hreflang="ms" data-title="Air batu laut" data-language-autonym="Bahasa Melayu" data-language-local-name="malayisk" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Zee-ijs" title="Zee-ijs – nederlandsk" lang="nl" hreflang="nl" data-title="Zee-ijs" data-language-autonym="Nederlands" data-language-local-name="nederlandsk" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E6%B5%B7%E6%B0%B7" title="海氷 – japansk" lang="ja" hreflang="ja" data-title="海氷" data-language-autonym="日本語" data-language-local-name="japansk" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Banquisa" title="Banquisa – oksitansk" lang="oc" hreflang="oc" data-title="Banquisa" data-language-autonym="Occitan" data-language-local-name="oksitansk" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/L%C3%B3d_morski" title="Lód morski – polsk" lang="pl" hreflang="pl" data-title="Lód morski" data-language-autonym="Polski" data-language-local-name="polsk" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Banquisa" title="Banquisa – portugisisk" lang="pt" hreflang="pt" data-title="Banquisa" data-language-autonym="Português" data-language-local-name="portugisisk" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Banchiz%C4%83" title="Banchiză – rumensk" lang="ro" hreflang="ro" data-title="Banchiză" data-language-autonym="Română" data-language-local-name="rumensk" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9C%D0%BE%D1%80%D1%81%D0%BA%D0%BE%D0%B9_%D0%BB%D1%91%D0%B4" title="Морской лёд – russisk" lang="ru" hreflang="ru" data-title="Морской лёд" data-language-autonym="Русский" data-language-local-name="russisk" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Sea_ice" title="Sea ice – enkel engelsk" lang="en-simple" hreflang="en-simple" data-title="Sea ice" data-language-autonym="Simple English" data-language-local-name="enkel engelsk" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Morski_led" title="Morski led – slovensk" lang="sl" hreflang="sl" data-title="Morski led" data-language-autonym="Slovenščina" data-language-local-name="slovensk" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9C%D0%BE%D1%80%D1%81%D0%BA%D0%B8_%D0%BB%D0%B5%D0%B4" title="Морски лед – serbisk" lang="sr" hreflang="sr" data-title="Морски лед" data-language-autonym="Српски / srpski" data-language-local-name="serbisk" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Merij%C3%A4%C3%A4" title="Merijää – finsk" lang="fi" hreflang="fi" data-title="Merijää" data-language-autonym="Suomi" data-language-local-name="finsk" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%95%E0%AE%9F%E0%AE%B1%E0%AF%8D%E0%AE%AA%E0%AE%A9%E0%AE%BF" title="கடற்பனி – tamil" lang="ta" hreflang="ta" data-title="கடற்பனி" data-language-autonym="தமிழ்" data-language-local-name="tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-chr mw-list-item"><a href="https://chr.wikipedia.org/wiki/%E1%8E%A0%E1%8E%BA%E1%8F%89%E1%8E%AF_%E1%8E%A4%E1%8F%81%E1%8F%8D%E1%8F%93%E1%8E%B3" title="ᎠᎺᏉᎯ ᎤᏁᏍᏓᎳ – cherokesisk" lang="chr" hreflang="chr" data-title="ᎠᎺᏉᎯ ᎤᏁᏍᏓᎳ" data-language-autonym="ᏣᎳᎩ" data-language-local-name="cherokesisk" class="interlanguage-link-target"><span>ᏣᎳᎩ</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Deniz_buzu" title="Deniz buzu – tyrkisk" lang="tr" hreflang="tr" data-title="Deniz buzu" data-language-autonym="Türkçe" data-language-local-name="tyrkisk" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9C%D0%BE%D1%80%D1%81%D1%8C%D0%BA%D0%B8%D0%B9_%D0%BB%D1%96%D0%B4" title="Морський лід – ukrainsk" lang="uk" hreflang="uk" data-title="Морський лід" data-language-autonym="Українська" data-language-local-name="ukrainsk" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/B%C4%83ng_bi%E1%BB%83n" title="Băng biển – vietnamesisk" lang="vi" hreflang="vi" data-title="Băng biển" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamesisk" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a 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title="Liste over spesialsider [q]" accesskey="q"><span>Spesialsider</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Sj%C3%B8is&oldid=3426098" title="Fast lenkje til denne versjonen av sida"><span>Fast lenkje</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Sj%C3%B8is&action=info" title="Meir informasjon om sida"><span>Sideinformasjon</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Spesial:Siter&page=Sj%C3%B8is&id=3426098&wpFormIdentifier=titleform" title="Informasjon om korleis ein siterer denne sida"><span>Siter denne sida</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Spesial:UrlShortener&url=https%3A%2F%2Fnn.wikipedia.org%2Fwiki%2FSj%25C3%25B8is"><span>Hent kort URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Spesial:QrCode&url=https%3A%2F%2Fnn.wikipedia.org%2Fwiki%2FSj%25C3%25B8is"><span>Last 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aria-label="Sideverktøy"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Utsjånad"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Utsjånad</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">flytt til sidefeltet</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">gøym</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">Frå Wikipedia – det frie oppslagsverket</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="nn" dir="ltr"><figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fil:Sea_ice.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Sea_ice.svg/220px-Sea_ice.svg.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Sea_ice.svg/330px-Sea_ice.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Sea_ice.svg/440px-Sea_ice.svg.png 2x" data-file-width="706" data-file-height="705" /></a><figcaption>Kart over den typiske yttergrensa til sjøisen i Arktis i mars og september.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fil:Seaice_%26_Edge%C3%B8ya.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Seaice_%26_Edge%C3%B8ya.jpg/220px-Seaice_%26_Edge%C3%B8ya.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Seaice_%26_Edge%C3%B8ya.jpg/330px-Seaice_%26_Edge%C3%B8ya.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Seaice_%26_Edge%C3%B8ya.jpg/440px-Seaice_%26_Edge%C3%B8ya.jpg 2x" data-file-width="1600" data-file-height="1200" /></a><figcaption>Tett sjøis i <a href="/wiki/Storfjorden_p%C3%A5_Svalbard" title="Storfjorden på Svalbard">Storfjorden</a> på Svalbard. <a href="/wiki/Edge%C3%B8ya" title="Edgeøya">Edgeøya</a> ligg i bakgrunnen. Dette er første års is, men dei sterke straumane i <a href="/w/index.php?title=Freemansundet&action=edit&redlink=1" class="new" title="Freemansundet (sida finst ikkje)">Freemansundet</a> har skrudd isen saman ganske kraftig.<div style="font-size:85%">Foto: Lars H. Smedsrud</div> </figcaption></figure> <p><b>Sjøis</b> (eller <b>havis</b>) er <a href="/wiki/Is" title="Is">frose</a> sjøvatn og dekker store havområde, både nord og sør på jordkloden. Sjøis frys når havet blir avkjølt under frysepunktet, ganske nært -1,8 °C. Viss sjøisen er brekt opp i mange små flak, blir han kalla <b>drivis</b>. </p><p>I nord er utbreiinga av sjøis om vinteren sør til <a href="/wiki/Austersj%C3%B8en" title="Austersjøen">Austersjøen</a> og <a href="/wiki/Newfoundland" title="Newfoundland">Newfoundland</a> i <a href="/wiki/Atlanterhavet" title="Atlanterhavet">Atlanterhavet</a>, og sør til <a href="/wiki/Alaska" title="Alaska">Alaskahalvøya</a> og <a href="/wiki/Japan" title="Japan">Japan</a> i <a href="/wiki/Stillehavet" title="Stillehavet">Stillehavet</a>. Sjøisen i <a href="/wiki/Arktis" title="Arktis">Arktis</a> dekker eit område tilsvarande Europa og skil eit forholdsvis varmt arktisk hav frå ein kald atmosfære. Han har den maksimale utbreiinga si i mars månad og når eit minimum i september. Gjennomsnittleg tjukkleik er 2-3 meter. Isen kan smelte både frå oversiden og undersida ved kontakt med varm luft eller varme havstraumar. Store område med ope hav mellom sjøisen vert kalla <a href="/wiki/Polynja" title="Polynja">polynja</a>. </p><p>Sjøisen er i rørsle, driven av <a href="/wiki/Vind" title="Vind">vinden</a> på oversida eller <a href="/wiki/Havstraum" title="Havstraum">havstraumane</a> på undersida. Dette fører til regionale skilnader i isdekket, og store svingingar frå år til år. Det er ei gjennomsnittleg drift av sjøisen frå <a href="/wiki/Beringstredet" class="mw-redirect" title="Beringstredet">Beringstredet</a> mellom Alaska og <a href="/wiki/Sibir" title="Sibir">Sibir</a> mot <a href="/wiki/Gr%C3%B8nland" title="Grønland">Grønland</a> og <a href="/wiki/Svalbard" title="Svalbard">Svalbard</a>, dette kallast den transpolare drifta. Dette vart første gongen dokumentert då <a href="/wiki/Fridtjof_Nansen" title="Fridtjof Nansen">Fridtjof Nansen</a> navigerte <a href="/wiki/%C2%ABFram%C2%BB" title="«Fram»">«Fram»</a> over <a href="/wiki/Polhavet" title="Polhavet">Polhavet</a> i åra 1893–1896. </p><p>I <a href="/wiki/Antarktis" title="Antarktis">Antarktis</a> dekkast havet nord til omtrent 60 °S av sjøis kvar vinter. Sjøisen i Antarktis har ei større endring av arealet gjennom året enn i nord, fordi det ikkje er nokre kontinent som avgrensar utbreiinga nordover. Sjøisen i sør er difor tynnare, og det aller meste smeltar kvar sommar, og frys igjen neste vinter. Dette blir kalla førsteårs sjøis. Overlever sjøisen ein sommar blir kalla han fleirårsis. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Målingar_av_sjøis"><span id="M.C3.A5lingar_av_sj.C3.B8is"></span>Målingar av sjøis</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Sj%C3%B8is&veaction=edit&section=1" title="Endre bolk: Målingar av sjøis" class="mw-editsection-visualeditor"><span>endre</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Sj%C3%B8is&action=edit&section=1" title="Rediger kildekoden til seksjonen Målingar av sjøis"><span>endre wikiteksten</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/Fil:NSIDC_arctic_sea_ice_extent_since_1979.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/NSIDC_arctic_sea_ice_extent_since_1979.svg/220px-NSIDC_arctic_sea_ice_extent_since_1979.svg.png" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/NSIDC_arctic_sea_ice_extent_since_1979.svg/330px-NSIDC_arctic_sea_ice_extent_since_1979.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4b/NSIDC_arctic_sea_ice_extent_since_1979.svg/440px-NSIDC_arctic_sea_ice_extent_since_1979.svg.png 2x" data-file-width="864" data-file-height="576" /></a><figcaption>Sesongvariasjon og langtidsutvikling i utstrekninga av området med arktisk sjøis, målt ved satellittar.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></figcaption></figure> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/Fil:Ice-floe_params_hg.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Ice-floe_params_hg.png/220px-Ice-floe_params_hg.png" decoding="async" width="220" height="108" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Ice-floe_params_hg.png/330px-Ice-floe_params_hg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Ice-floe_params_hg.png/440px-Ice-floe_params_hg.png 2x" data-file-width="2800" data-file-height="1373" /></a><figcaption>Parameter for å måle storleiken på ein straum av sjøis.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fil:Isfjorden_Adventtoppen_IMG_2623.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Isfjorden_Adventtoppen_IMG_2623.JPG/220px-Isfjorden_Adventtoppen_IMG_2623.JPG" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Isfjorden_Adventtoppen_IMG_2623.JPG/330px-Isfjorden_Adventtoppen_IMG_2623.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Isfjorden_Adventtoppen_IMG_2623.JPG/440px-Isfjorden_Adventtoppen_IMG_2623.JPG 2x" data-file-width="3888" data-file-height="2592" /></a><figcaption>Delvis sjøis inst i <a href="/wiki/Adventfjorden" title="Adventfjorden">Adventfjorden</a> ved <a href="/wiki/Longyearbyen" title="Longyearbyen">Longyearbyen</a> på Svalbard.</figcaption></figure> <figure typeof="mw:File/Thumb"><a href="/wiki/Fil:Isfjorden_IMG_2564.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/39/Isfjorden_IMG_2564.JPG/235px-Isfjorden_IMG_2564.JPG" decoding="async" width="235" height="353" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/39/Isfjorden_IMG_2564.JPG/353px-Isfjorden_IMG_2564.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/39/Isfjorden_IMG_2564.JPG/470px-Isfjorden_IMG_2564.JPG 2x" data-file-width="2592" data-file-height="3888" /></a><figcaption>Drivis på <a href="/wiki/Isfjorden_p%C3%A5_Svalbard" title="Isfjorden på Svalbard">Isfjorden</a> på Svalbard, seint i april.</figcaption></figure> <p>Ved hjelp av satellittmålingar har ein gode observasjonar av isutbreiinga frå 1979 og fram til i dag, medan informasjon lenger tilbake i tid er meir usikker. Den europeiske miljøsatellitten <a href="/wiki/Envisat" title="Envisat">Envisat</a> og amerikanske satellittar fotograferer både Arktis og Antarktis og gjer isobservasjonar. Desse vert handsama for nordlege <a href="/wiki/Norskehavet" title="Norskehavet">Norskehavet</a> og <a href="/wiki/Svalbard" title="Svalbard">Svalbard</a> av <a href="/wiki/Meteorologisk_institutt" title="Meteorologisk institutt">Meteorologisk institutt</a>, og formidlast mellom anna gjennom <a href="/w/index.php?title=Maritim_radio&action=edit&redlink=1" class="new" title="Maritim radio (sida finst ikkje)">Maritim radio</a>. På Svalbard er <a href="/w/index.php?title=Svalsat&action=edit&redlink=1" class="new" title="Svalsat (sida finst ikkje)">Svalsat</a> engasjert i å hente ned satellittdata frå 14 sirkumpolare satellittar, mellom anna fleire som gjer ismålingar. </p><p>Det er no mogleg å følgje utbreiinga av is dagleg med desse målingane. Variasjonen gjennom året er formidabel; 15 millionar km² på vinteren til 7 millionar km² på sommaren. Den årlege smeltinga og isveksten dekker altså eit område like stort som Australia. </p> <div class="mw-heading mw-heading3"><h3 id="Historisk_rekord_i_Arktis_i_2007">Historisk rekord i Arktis i 2007</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Sj%C3%B8is&veaction=edit&section=2" title="Endre bolk: Historisk rekord i Arktis i 2007" class="mw-editsection-visualeditor"><span>endre</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Sj%C3%B8is&action=edit&section=2" title="Rediger kildekoden til seksjonen Historisk rekord i Arktis i 2007"><span>endre wikiteksten</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>September 2007 nådde isutbreiinga i Arktis det lågaste nivået sitt sidan satellittmålingane starta i 1979.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Samanlikna med gjennomsnittet for september i perioden 1979–2000 var isdekket 40 % mindre enn det pleier å vere. </p><p>Denne rekorden skuldast derimot ikkje berre auka temperatur, men òg uvanleg sterk vind som pressa store delar av isen sørover og på den måten førte til kraftig auke i smeltinga. Det totale skydekket over sommarsesongen var lågare enn tidlegare år<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> og isen var tynnare enn før ved starten av smeltesesongen.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Årsaker_til_redusert_sjøis"><span id=".C3.85rsaker_til_redusert_sj.C3.B8is"></span>Årsaker til redusert sjøis</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Sj%C3%B8is&veaction=edit&section=3" title="Endre bolk: Årsaker til redusert sjøis" class="mw-editsection-visualeditor"><span>endre</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Sj%C3%B8is&action=edit&section=3" title="Rediger kildekoden til seksjonen Årsaker til redusert sjøis"><span>endre wikiteksten</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Det er brei semje blant klimaforskarar at det er temperaturauken som er hovudårsaka til at sjøisen i Arktis reduserast. Likevel er det ganske store skilnader mellom klimamodellane, og når dei bereknar at isen er borte på sommaren. Dei fleste bereknar ein vesentleg reduksjon dette hundreåret, og nokre modellar bereknar eit Arktis heilt utan sjøis i september 2100. </p><p>Noko av reduksjonen kan skuldast is som har drive ut mellom Svalbard og Grønland og smelta, noko er mindre frysing inne i Polhavet og noko skulda moglegvis at isen er pressa saman til tjukke <a href="/wiki/Skruis" title="Skruis">skrugardar</a>. Eit hovudproblem med utrekningane av smelting frå arealet er at det finst få målingar av istjukkleiken.<sup id="cite_ref-faktaark_5-0" class="reference"><a href="#cite_note-faktaark-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Nokre_effektar_av_sjøisen"><span id="Nokre_effektar_av_sj.C3.B8isen"></span>Nokre effektar av sjøisen</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Sj%C3%B8is&veaction=edit&section=4" title="Endre bolk: Nokre effektar av sjøisen" class="mw-editsection-visualeditor"><span>endre</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Sj%C3%B8is&action=edit&section=4" title="Rediger kildekoden til seksjonen Nokre effektar av sjøisen"><span>endre wikiteksten</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Sjøisen frys raskast i store opningar i isen som blir kalla <a href="/wiki/Polynja" title="Polynja">polynjaer</a>. Havet under blir då tilsett salt som blir pressa ut under frysinga og dette vatnet blir tungt nok til å søkke ned og danne botnvatnet i verdshava.</li> <li>Sjøis reflekterer omkring 75 % av all solinnstråling, medan ope hav berre reflekterer omkring 15 %.</li> <li>Mindre sjøis gjev auka energioverføring frå havet til atmosfæren. Lufta over isen blir dermed varma opp og det blir danna fleire skyer, som igjen gjer at det blir reflektert meir sollys. Modellresultat viser at i framtida er det om vinteren denne oppvarminga blir mest effektiv, fordi det då ikkje er nokre solinnstråling i Arktis.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Kjelder">Kjelder</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Sj%C3%B8is&veaction=edit&section=5" title="Endre bolk: Kjelder" class="mw-editsection-visualeditor"><span>endre</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Sj%C3%B8is&action=edit&section=5" title="Rediger kildekoden til seksjonen Kjelder"><span>endre wikiteksten</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="references-small"> <ul><li><i>Denne artikkelen bygger på «<a href="https://no.wikipedia.org/wiki/Sj%C3%B8is" class="extiw" title="nb:Sjøis">Sjøis</a>» frå <a href="https://no.wikipedia.org/wiki/Hovedside" class="extiw" title="nb:Hovedside">Wikipedia på bokmål</a>, den 10. september 2011.</i> <ul><li><i><a href="https://no.wikipedia.org/wiki/Hovedside" class="extiw" title="nb:Hovedside">Wikipedia på bokmål</a> oppgav desse kjeldene:</i></li></ul></li></ul> </div> <style data-mw-deduplicate="TemplateStyles:r3318915">.mw-parser-output .reflist{font-size:90%;margin-bottom:0.5em;list-style-type:decimal}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text">Fetterer, F., K. Knowles, W. Meier, and M. Savoie. 2002, oppdatert 2010. Havisindeks. Boulder, Colorado USA: National Snow and Ice Data Center.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://earthobservatory.nasa.gov/IOTD/view.php?id=8074">Record Arctic Sea Ice Loss in 2007</a> (engelsk)</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a></span> <span class="reference-text"><cite class="citation"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120312141846/http://www.agu.org/pubs/crossref/2008/2008GL033451.shtml"><i>Kay, J. E., T. L'Ecuyer, A. Gettelman, G. Stephens, and C. O'Dell (2008), The contribution of cloud and radiation anomalies to the 2007 Arctic sea ice extent minimum, Geophys. Res. Lett., 35, L08503, doi:10.1029/2008GL033451</i></a>, arkivert frå <a rel="nofollow" class="external text" href="http://www.agu.org/pubs/crossref/2008/2008GL033451.shtml">originalen</a> 12. mars 2012<span class="reference-accessdate">, henta 10. september 2011</span></cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fnn.wikipedia.org%3ASj%C3%B8is&rft.btitle=Kay%2C+J.+E.%2C+T.+L%27Ecuyer%2C+A.+Gettelman%2C+G.+Stephens%2C+and+C.+O%27Dell+%282008%29%2C+The+contribution+of+cloud+and+radiation+anomalies+to+the+2007+Arctic+sea+ice+extent+minimum%2C+Geophys.+Res.+Lett.%2C+35%2C+L08503%2C+doi%3A10.1029%2F2008GL033451&rft.genre=book&rft_id=http%3A%2F%2Fwww.agu.org%2Fpubs%2Fcrossref%2F2008%2F2008GL033451.shtml&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://nsidc.org/news/press/2007_seaiceminimum/20071001_pressrelease.html">Arctic Sea Ice Shatters All Previous Record Lows</a> National Snow and Ice Data Center (NSIDC)</span> </li> <li id="cite_note-faktaark-5"><span class="mw-cite-backlink"><a href="#cite_ref-faktaark_5-0">↑</a></span> <span class="reference-text"><cite class="citation"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20091004061324/http://www.bjerknes.uib.no/pages.asp?kat=124&lang=1"><i>Faktaark om Arktis frå Bjerknes senteret</i></a>, arkivert frå <a rel="nofollow" class="external text" href="http://www.bjerknes.uib.no/pages.asp?kat=124&lang=1">originalen</a> 4. oktober 2009<span class="reference-accessdate">, henta 10. september 2011</span></cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fnn.wikipedia.org%3ASj%C3%B8is&rft.btitle=Faktaark+om+Arktis+fr%C3%A5+Bjerknes+senteret&rft.genre=book&rft_id=http%3A%2F%2Fwww.bjerknes.uib.no%2Fpages.asp%3Fkat%3D124%26lang%3D1&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></span> </li> </ol></div></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r3515230">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist 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