{"id":13469,"date":"2016-10-14T00:00:10","date_gmt":"2016-10-13T22:00:10","guid":{"rendered":"http:\/\/www.laterredufutur.com\/accueil\/?p=13469"},"modified":"2016-10-14T13:16:51","modified_gmt":"2016-10-14T11:16:51","slug":"le-niveau-doxygene-de-la-terre-de-ne-cesse-de-decliner","status":"publish","type":"post","link":"https:\/\/www.laterredufutur.com\/accueil\/le-niveau-doxygene-de-la-terre-de-ne-cesse-de-decliner\/","title":{"rendered":"Le niveau d&rsquo;oxyg\u00e8ne de la Terre ne cesse de d\u00e9cliner"},"content":{"rendered":"<div class=\"1665f18d14f35dd9e7566e1a8ac9a3e9\" data-index=\"1\" style=\"float: none; margin:10px 0 10px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block; text-align:center;\"\r\n     data-ad-layout=\"in-article\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-client=\"ca-pub-2860849627502538\"\r\n     data-ad-slot=\"3019501113\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script>\n<\/div>\n<p style=\"text-align: justify;\">D\u2019apr\u00e8s une r\u00e9cente \u00e9tude, des scientifiques ont d\u00e9couvert que le taux d\u2019oxyg\u00e8ne ne cesse de diminuer dans l\u2019atmosph\u00e8re de notre plan\u00e8te. Etant l\u2019\u00e9l\u00e9ment essentiel pour toute forme de vie, est-ce que ce ph\u00e9nom\u00e8ne met notre esp\u00e8ce en danger ?<\/p>\n<p style=\"text-align: justify;\">UNE BAISSE DE 0,7%<br \/>\nAu cours des 800 000 derni\u00e8res ann\u00e9es, le taux moyen d\u2019oxyg\u00e8ne contenu dans l\u2019atmosph\u00e8re de la Terre ne cesse de r\u00e9duire. Durant ce laps de temps, il a baiss\u00e9 de 0,7%. Autant vous rassurer de suite, cela n\u2019a rien de dramatique mais \u00e7a peut repr\u00e9senter un signal d\u2019alerte pour notre plan\u00e8te.<\/p>\n<p style=\"text-align: justify;\">Avant l\u2019apparition de toute forme de vie sur Terre, l\u2019atmosph\u00e8re terrestre ne poss\u00e9dait pas du tout d\u2019oxyg\u00e8ne. C\u2019est \u00e0 la suite de l\u2019apparition des premi\u00e8res cyanobact\u00e9ries que notre atmosph\u00e8re a vu le taux de ce gaz augmenter en ayant une concentration stable pendant des centaines de millions d\u2019ann\u00e9es qui ont suivi.<\/p>\n<p style=\"text-align: justify;\">Sauf que derni\u00e8rement, une \u00e9quipe de scientifiques de l\u2019universit\u00e9 de Princeton a confirm\u00e9 que le taux moyen d\u2019oxyg\u00e8ne n\u2019a cess\u00e9 de d\u00e9cliner au cours de ces derni\u00e8res centaines de milliers d\u2019ann\u00e9es. C\u2019est apr\u00e8s avoir analys\u00e9 des \u00e9chantillons de glace pr\u00e9lev\u00e9s en Antarctique et au Groenland qui conservent des bulles de gaz de l\u2019atmosph\u00e8re que ces chercheurs en sont parvenus \u00e0 cette conclusion.<\/p><div class=\"1665f18d14f35dd9e7566e1a8ac9a3e9\" data-index=\"2\" style=\"float: none; margin:10px 0 10px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block; text-align:center;\"\r\n     data-ad-layout=\"in-article\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-client=\"ca-pub-2860849627502538\"\r\n     data-ad-slot=\"3019501113\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script>\n<\/div>\n\n<p style=\"text-align: justify;\">DEUX HYPOTH\u00c8SES POUR EXPLIQUER CE PH\u00c9NOM\u00c8NE<br \/>\nPour tenter de trouver une explication \u00e0 ces changements, les experts proposent deux hypoth\u00e8ses : la premi\u00e8re, il s\u2019agit d\u2019un ph\u00e9nom\u00e8ne d\u2019\u00e9rosion qui s\u2019acc\u00e9l\u00e8rent et qui entra\u00eene dans le m\u00eame temps des processus d\u2019oxydation. Ou bien, la seconde hypoth\u00e8se repose sur le fait que la temp\u00e9rature moyenne de l\u2019hydrosph\u00e8re a baiss\u00e9 lors des derniers millions d\u2019ann\u00e9es ce qui implique que les oc\u00e9ans absorbent davantage d\u2019oxyg\u00e8ne qu\u2019avant.<\/p>\n<p style=\"text-align: justify;\">Une autre conclusion int\u00e9ressante ressort de cette \u00e9tude : si l\u2019on fait abstraction des 150 derni\u00e8res ann\u00e9es, le taux de dioxyde de carbone est quant \u00e0 lui rest\u00e9 relativement stable. Un fait assez surprenant puisque les niveaux de CO2 ont tendance \u00e0 augmenter \u00e0 mesure que l\u2019oxyg\u00e8ne diminue. Toujours est-il qu\u2019il est n\u00e9cessaire de r\u00e9aliser davantage de recherches dans le but de d\u00e9terminer de quelle fa\u00e7on l\u2019oxyg\u00e8ne et le dioxyde de carbone interagissent entre eux dans l\u2019atmosph\u00e8re de notre plan\u00e8te sur de tr\u00e8s longues p\u00e9riodes.<\/p>\n<p style=\"text-align: justify;\">source :\u00a0<a href=\"http:\/\/hitek.fr\/actualite\/diminution-taux-moyen-oxygene-terre-atmosphere_10763\" target=\"_blank\">http:\/\/hitek.fr\/<\/a><\/p>\n<p class=\"bawpvc-ajax-counter\" data-id=\"13469\">(652)<\/p>\n<!--CusAds0-->\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>D\u2019apr\u00e8s une r\u00e9cente \u00e9tude, des scientifiques ont d\u00e9couvert que le taux d\u2019oxyg\u00e8ne ne cesse de diminuer dans l\u2019atmosph\u00e8re de notre&#8230;<\/p>\n","protected":false},"author":1,"featured_media":12362,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"ngg_post_thumbnail":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":true,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Le niveau d'oxyg\u00e8ne de la Terre de ne cesse de d\u00e9cliner @laterredufutur","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[31],"tags":[252,93,2190,234,286,75],"class_list":["post-13469","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-divers","tag-atmosphere","tag-co2","tag-niveau","tag-oceans","tag-oxygene","tag-terre","wpcat-31-id"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2016\/05\/Terre-photo-Nasa-espace-6.jpg?fit=1070%2C431&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p631RN-3vf","jetpack-related-posts":[{"id":25378,"url":"https:\/\/www.laterredufutur.com\/accueil\/la-chute-extreme-du-taux-doxygene-etouffera-un-jour-la-plupart-des-formes-de-notre-monde\/","url_meta":{"origin":13469,"position":0},"title":"La chute extr\u00eame du taux d&rsquo;oxyg\u00e8ne \u00e9touffera un jour la plupart des formes de vie de notre monde","author":"Admin","date":"22 novembre 2023","format":false,"excerpt":"Pour l'instant, la vie s'\u00e9panouit sur notre plan\u00e8te riche en oxyg\u00e8ne, mais la Terre n'a pas toujours \u00e9t\u00e9 ainsi. Les scientifiques ont pr\u00e9dit qu'\u00e0 l'avenir, l'atmosph\u00e8re redeviendra riche en m\u00e9thane et pauvre en oxyg\u00e8ne. Cela ne se produira probablement pas avant un milliard d'ann\u00e9es. Mais lorsque le changement interviendra, il\u2026","rel":"","context":"Dans &quot;Monde Futur&quot;","block_context":{"text":"Monde Futur","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/monde-futur\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/05\/planete-terre-ocean.jpg?fit=1200%2C792&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/05\/planete-terre-ocean.jpg?fit=1200%2C792&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/05\/planete-terre-ocean.jpg?fit=1200%2C792&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/05\/planete-terre-ocean.jpg?fit=1200%2C792&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/05\/planete-terre-ocean.jpg?fit=1200%2C792&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":26965,"url":"https:\/\/www.laterredufutur.com\/accueil\/un-monde-qui-finira-sans-oxygene\/","url_meta":{"origin":13469,"position":1},"title":"Un monde qui finira sans oxyg\u00e8ne","author":"Admin","date":"8 juin 2025","format":false,"excerpt":"Une chute extr\u00eame de l'oxyg\u00e8ne finira par \u00e9touffer la plupart des formes de vie sur Terre. Pour l'instant, la vie complexe prosp\u00e8re sur notre plan\u00e8te gr\u00e2ce \u00e0 son apport en oxyg\u00e8ne . Mais l'atmosph\u00e8re terrestre n'a pas toujours \u00e9t\u00e9 ce qu'elle est aujourd'hui, et les scientifiques pr\u00e9disent qu'\u00e0 l'avenir, elle\u2026","rel":"","context":"Dans &quot;Monde Futur&quot;","block_context":{"text":"Monde Futur","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/monde-futur\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":26700,"url":"https:\/\/www.laterredufutur.com\/accueil\/leau-tres-chaude-de-yellowstone-pourrait-renfermer-les-secrets-de-la-premiere-respiration-de-la-terre\/","url_meta":{"origin":13469,"position":2},"title":"L&rsquo;eau tr\u00e8s chaude de Yellowstone pourrait renfermer les secrets de la premi\u00e8re respiration de la Terre","author":"Admin","date":"17 f\u00e9vrier 2025","format":false,"excerpt":"La vie microbienne dans le bassin inf\u00e9rieur des geysers de Yellowstone pourrait fournir des indices sur l'\u00e9volution de l'exploitation de l'oxyg\u00e8ne par la vie, selon une analyse r\u00e9cente r\u00e9alis\u00e9e par des chercheurs de l'universit\u00e9 d'\u00c9tat du Montana. Les habitants des sources Octopus et Conch du bassin vivent dans des structures\u2026","rel":"","context":"Dans &quot;Seismes\/Volcans&quot;","block_context":{"text":"Seismes\/Volcans","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/seismes-et-volcans\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/08\/yellowstone.jpg?fit=1024%2C679&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/08\/yellowstone.jpg?fit=1024%2C679&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/08\/yellowstone.jpg?fit=1024%2C679&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/08\/yellowstone.jpg?fit=1024%2C679&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":24577,"url":"https:\/\/www.laterredufutur.com\/accueil\/loxygene-de-la-terre-provient-dune-source-interne-a-notre-planete-selon-une-etude\/","url_meta":{"origin":13469,"position":3},"title":"L&rsquo;oxyg\u00e8ne de la Terre provient d&rsquo;une source interne \u00e0 notre plan\u00e8te, selon une \u00e9tude","author":"Admin","date":"6 d\u00e9cembre 2022","format":false,"excerpt":"La quantit\u00e9 d'oxyg\u00e8ne dans l'atmosph\u00e8re de la Terre en fait une plan\u00e8te habitable. Vingt et un pour cent de l'atmosph\u00e8re est constitu\u00e9 de cet \u00e9l\u00e9ment vital. Mais dans un pass\u00e9 lointain - aussi loin que l'\u00e8re n\u00e9o-arch\u00e9enne, il y a 2,8 \u00e0 2,5 milliards d'ann\u00e9es - cet oxyg\u00e8ne \u00e9tait presque\u2026","rel":"","context":"Dans &quot;Divers&quot;","block_context":{"text":"Divers","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/divers\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2022\/12\/terre-oxygene.jpg?fit=1024%2C533&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":7839,"url":"https:\/\/www.laterredufutur.com\/accueil\/planete-terre-la-vie-sous-la-glace\/","url_meta":{"origin":13469,"position":4},"title":"Plan\u00e8te Terre &#8211; La Vie Sous La Glace","author":"Admin","date":"13 ao\u00fbt 2015","format":false,"excerpt":"Au cours de ses 4,6 milliards d'ann\u00e9es de vie, la Terre a connu de grands bouleversements provoqu\u00e9s par des chocs avec des objets venant de l'espace ou lors des soubresauts de son noyau interne. C'est pourtant sur cette plan\u00e8te que la vie est apparue et s'est lentement transform\u00e9e, malgr\u00e9 tous\u2026","rel":"","context":"Dans &quot;Seismes\/Volcans&quot;","block_context":{"text":"Seismes\/Volcans","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/seismes-et-volcans\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2015\/04\/glace-et-banquise1.jpg?fit=1024%2C768&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2015\/04\/glace-et-banquise1.jpg?fit=1024%2C768&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2015\/04\/glace-et-banquise1.jpg?fit=1024%2C768&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2015\/04\/glace-et-banquise1.jpg?fit=1024%2C768&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":24794,"url":"https:\/\/www.laterredufutur.com\/accueil\/les-oceans-ont-tres-probablement-borde-venus-avant-quelle-ne-devienne-un-enfer\/","url_meta":{"origin":13469,"position":5},"title":"Les oc\u00e9ans ont tr\u00e8s probablement bord\u00e9 V\u00e9nus avant qu&rsquo;elle ne devienne un enfer","author":"Admin","date":"13 mars 2023","format":false,"excerpt":"V\u00e9nus est peut-\u00eatre l'un des objets les plus brillants et les plus beaux de notre ciel nocturne, mais il ne faut pas s'y tromper. Notre plan\u00e8te voisine est extr\u00eamement inhospitali\u00e8re par rapport \u00e0 la vie telle que nous la connaissons. C'est un monde toxique et br\u00fblant sur lequel les humains\u2026","rel":"","context":"Dans &quot;Espace&quot;","block_context":{"text":"Espace","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/espace\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2020\/11\/venus-terraformee-5.jpg?fit=960%2C540&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2020\/11\/venus-terraformee-5.jpg?fit=960%2C540&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2020\/11\/venus-terraformee-5.jpg?fit=960%2C540&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2020\/11\/venus-terraformee-5.jpg?fit=960%2C540&ssl=1&resize=700%2C400 2x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/13469","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/comments?post=13469"}],"version-history":[{"count":2,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/13469\/revisions"}],"predecessor-version":[{"id":13632,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/13469\/revisions\/13632"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media\/12362"}],"wp:attachment":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media?parent=13469"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/categories?post=13469"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/tags?post=13469"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}