{"id":3936,"date":"2007-04-05T19:59:22","date_gmt":"2007-04-05T17:59:22","guid":{"rendered":"http:\/\/www.laterredufutur.com\/accueil1\/?p=3936"},"modified":"2015-04-11T20:01:00","modified_gmt":"2015-04-11T18:01:00","slug":"dossier-n-2-les-courants-marins","status":"publish","type":"post","link":"https:\/\/www.laterredufutur.com\/accueil\/dossier-n-2-les-courants-marins\/","title":{"rendered":"Dossier N\u00b0 2 : Les Courants Marins"},"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>Voici un dossier, en\u00a04 parties qui seront publi\u00e9es sur la Terre du Futur, transmis par <span style=\"color: #004a9d;\">Fifi321fth (Thomas), <\/span>pass\u00e9 au lyc\u00e9e Sacr\u00e9-Coeur \u00e0 Reims.<\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Thomas <span style=\"font-size: small;\"><span style=\"color: #2b2bff; font-family: ComicSansMS-Bold;\">L., <\/span><\/span>Enguerran D., <\/span><span style=\"font-family: ComicSansMS-Bold; font-size: small;\"><span style=\"color: #2b2bff;\">Juliette M.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Dossier Exclusif sur les Courants Marins et de ce qui en r\u00e9sulte.<\/span><\/p>\n<p><span style=\"color: #ffffff;\">Ici 2 eme partie&#8230;<\/span><\/p>\n<p align=\"justify\">d) les diff\u00e9rences de densit\u00e9 (salinit\u00e9)<\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff; font-size: small;\">Il existe des courants marins appel\u00e9s <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"color: #2b2bff; font-size: small;\">Courants de densit\u00e9<\/span><\/span><\/b><span style=\"color: #2b2bff;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">. Comme <\/span><span style=\"font-size: small;\">leur nom l&rsquo;indique, ils sont li\u00e9s \u00e0 la densit\u00e9 de l&rsquo;eau. Ils sont \u00e0 l&rsquo;origine <\/span><span style=\"font-size: small;\">des <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"font-size: small;\">eaux profondes<\/span><\/span><\/b><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">, plus sal\u00e9es et plus denses, qui coulent donc plus en <\/span><span style=\"font-size: small;\">profondeur (voir exp\u00e9riences sur le montage), ils permettent \u00e0 ces eaux <\/span><span style=\"font-size: small;\">d&rsquo;atteindre parfois la surface.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Suivant la latitude, on observe des diff\u00e9rences de tempr\u00e9ature. Cette <\/span><span style=\"font-size: small;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant7.jpg?resize=256%2C256\" alt=\"\" width=\"256\" height=\"256\" align=\"left\" \/>diff\u00e9rence de tempr\u00e9rature entra\u00eene une diff\u00e9rence de salinit\u00e9 de l&rsquo;eau <\/span><span style=\"font-size: small;\">et donc de densit\u00e9 (\u00e0 cause de l&rsquo;\u00e9vaporation et de la fonte des glaces en\u00a0 <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">composante horizontale de la force de Coriolis est nulle. La variation de la <\/span><span style=\"font-size: small;\">force de Coriolis donne donc diff\u00e9rents r\u00e9gimes de circulation<\/span><span style=\"font-size: small;\">atmosph\u00e9rique selon la latitude.<\/span><\/span><\/span><\/p>\n<p align=\"justify\">\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Dans la figure, on voit comment cela se produit en prenant les quatre <\/span><span style=\"font-size: small;\">points cardinaux comme d\u00e9but de l&rsquo;interaction des forces. Le gradient de <\/span><span style=\"font-size: small;\">pression (fl\u00e8ches bleues) amorce le d\u00e9placement de l&rsquo;air mais la force de <\/span><span style=\"font-size: small;\">Coriolis (fl\u00e8ches rouges) le fait d\u00e9vier vers la droite (fl\u00e8ches noires). Le <\/span><span style=\"font-size: small;\">gradient de pression s&rsquo;ajuste en direction avec ce changement ainsi que<\/span><span style=\"font-size: small;\">la force de Coriolis ce qui fait changer continuellement la direction de <\/span><span style=\"font-size: small;\">notre parcelle.<\/span><\/span><\/p>\n<p align=\"justify\">d) les diff\u00e9rences de densit\u00e9 (salinit\u00e9)<\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff; font-size: small;\">Il existe des courants marins appel\u00e9s <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"color: #2b2bff; font-size: small;\">Courants de densit\u00e9<\/span><\/span><\/b><span style=\"color: #2b2bff;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">. Comme <\/span><span style=\"font-size: small;\">leur nom l&rsquo;indique, ils sont li\u00e9s \u00e0 la densit\u00e9 de l&rsquo;eau. Ils sont \u00e0 l&rsquo;origine <\/span><span style=\"font-size: small;\">des <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"font-size: small;\">eaux profondes<\/span><\/span><\/b><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">, plus sal\u00e9es et plus denses, qui coulent donc plus en <\/span><span style=\"font-size: small;\">profondeur (voir exp\u00e9riences sur le montage), ils permettent \u00e0 ces eaux <\/span><span style=\"font-size: small;\">d&rsquo;atteindre parfois la surface.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">Suivant la latitude, on observe des diff\u00e9rences de tempr\u00e9ature. Cette <\/span><span style=\"font-size: small;\">diff\u00e9rence de tempr\u00e9rature entra\u00eene une diff\u00e9rence de salinit\u00e9 de l&rsquo;eau <\/span><span style=\"font-size: small;\">et donc de densit\u00e9 (\u00e0 cause de l&rsquo;\u00e9vaporation et de la fonte des glaces en <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">\u00e9t\u00e9), cr\u00e9ant ainsi des <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"font-size: small;\">courants de profondeur<\/span><\/span><\/b><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff; font-size: small;\">.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ces courants sont bas\u00e9s sur des diff\u00e9rences de temp\u00e9rature (l&rsquo;eau <\/span><span style=\"font-size: small;\">froide est plus dense que l&rsquo;eau chaude), et de salinit\u00e9 (l&rsquo;eau sal\u00e9e est plus <\/span><span style=\"font-size: small;\">dense que l&rsquo;eau douce) entre les diff\u00e9rentes couches de l&rsquo;oc\u00e9an.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les eaux chaudes de surface se chargent en sel \u00e0 cause de l&rsquo;\u00e9vaporation, <\/span><span style=\"font-size: small;\">ce qui les rend plus denses. <\/span><span style=\"font-size: small;\">En hiver, lors de la formation de la banquise, la glace un fois form\u00e9e <\/span><span style=\"font-size: small;\">d\u00e9gage du sel qui alourdit l&rsquo;eau non gel\u00e9e qui devient plus dense, ce qui <\/span><span style=\"font-size: small;\">fait qu&rsquo;elle plonge plus en profondeur.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les courants de surface et les courants profonds sont <\/span><span style=\"font-size: small;\">interconnect\u00e9s. Il existe une expression venue de l&rsquo;imanigation des <\/span><span style=\"font-size: small;\">hommes qu&rsquo;est le <\/span><\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"color: #2b2bff; font-size: small;\">Tapis roulant <\/span><\/span><\/b><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">pour d\u00e9crire le transport d&rsquo;eaux <\/span><span style=\"font-size: small;\">profondes de l&rsquo;Atlantique vers le Pacifique et son retour en surface.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Gr\u00e2ce \u00e0 la capacit\u00e9 thermique de l&rsquo;eau, l&rsquo;oc\u00e9an est un immense r\u00e9servoir <\/span><span style=\"font-size: small;\">de chaleur. <\/span><span style=\"font-size: small;\">Les eaux refroidies et sal\u00e9es plongent au niveau des hautes latitudes.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff; font-size: small;\">Le <\/span><\/span><b><span style=\"font-family: ComicSansMS-Bold;\"><span style=\"color: #2b2bff; font-size: small;\">Gulf Stream <\/span><\/span><\/b><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">est un exemple de courant marin affect\u00e9 par les <\/span><span style=\"font-size: small;\">diff\u00e9rences de densit\u00e9s.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant8.jpg?resize=700%2C500\" alt=\"\" width=\"700\" height=\"500\" \/><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Sh\u00e9ma simplifi\u00e9 de la circulation Thermohaline globale <\/span><span style=\"font-size: small;\">( conveyor belt : \u201cTapis roulant\u201d)<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS; font-size: small;\"><span style=\"color: #2b2bff;\">e) La diff\u00e9rence de hauteur d&rsquo;eau (SSH)<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">La diff\u00e9rence de hauteur d&rsquo;eau est un principe de fluides tr\u00e8s simple <\/span><span style=\"font-size: small;\">\u00e0 comprendre. L&rsquo;eau coule, or elle coule, attir\u00e9e par la gravit\u00e9 terrestre.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Donc elle ne coule que du haut vers le bas et non du bas vers le haut, <\/span><span style=\"font-size: small;\">c&rsquo;est ce concept qui intervient \u00e9galement dans la circulation thermohaline <\/span><span style=\"font-size: small;\">g\u00e9n\u00e9rale.<\/span><\/span><\/p>\n<p align=\"center\"><span style=\"color: #2b2bff; font-size: small;\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant9.jpg\" alt=\"\" \/><\/span><\/p>\n<p align=\"justify\">Sch\u00e9ma de la SSH (hauteur de la surface de la mer)<\/p>\n<p align=\"justify\">f) Des influences animales marines ?<\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS; font-size: small;\"><span style=\"color: #2b2bff;\">Il est admis qu&rsquo;il y aurait une cause animale au fonctionnement des <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">courants marins, ou au moins pour une partie peut-\u00eatre minime de la force <\/span><span style=\"font-size: small;\">des courants marins. En effet, il semblerait que les bancs de poissons ou <\/span><span style=\"font-size: small;\">de baleines, qui nagent au gr\u00e9 des grands courants marins, auraient une <\/span><span style=\"font-size: small;\">influence sur la puissance des courants marins, on l&rsquo;estimerait, pour le <\/span><span style=\"font-size: small;\">Gulf Stream seul, \u00e0 plusieurs t\u00e9rawatts !<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">II.L&rsquo;influence des courants marins<\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">1\u00b0) Les influences thermiques et pluviom\u00e9triques des <\/span><span style=\"font-size: small;\">courants marins permanents. <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">L\u2019effet du vent sur la surface de la mer cr\u00e9e des courants dont <\/span><span style=\"font-size: small;\">l\u2019intensit\u00e9 et la direction varient avec la profondeur. Ces courants <\/span><span style=\"font-size: small;\">constituent le principal facteur du transport et renouvellement des eaux <\/span><span style=\"font-size: small;\">sur le plateau continental. En hiver, les courants de surface sont plut\u00f4t <\/span><span style=\"font-size: small;\">dirig\u00e9s vers le nord sous l\u2019effet des vents d&rsquo; Ouest \u00e0 Sud Ouest <\/span><span style=\"font-size: small;\">dominants alors qu\u2019ils se dirigent vers le sud ouest au printemps et en \u00e9t\u00e9 <\/span><span style=\"font-size: small;\">sous l\u2019influence des vents dominants de Nord Ouest. Toutefois, ces <\/span><span style=\"font-size: small;\">sch\u00e9mas de circulation ne repr\u00e9sentent qu\u2019une moyenne. Ils sont, \u00e0 court <\/span><span style=\"font-size: small;\">terme, tributaires de l\u2019alternance des r\u00e9gimes m\u00e9t\u00e9orologiques.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les effets fluviaux contribuent, de mani\u00e8re g\u00e9n\u00e9rale, en Automne et <\/span><span style=\"font-size: small;\">en hiver \u00e0 accentuer le d\u00e9placement vers le Nord des masses d&rsquo;eau le <\/span><span style=\"font-size: small;\">long des c\u00f4tes fran\u00e7aises. <\/span><span style=\"font-size: small;\">Les eaux chaudes du Gulf Stream exercent une influence<\/span><span style=\"font-size: small;\">consid\u00e9rable sur les climats europ\u00e9ens. La fa\u00e7ade atlantique du continent, <\/span><span style=\"font-size: small;\">de Lisbonne (Portugal) \u00e0 Oslo (Norv\u00e8ge), jouit ainsi qu&rsquo;une grande <\/span><span style=\"font-size: small;\">douceur climatique, avec une variation annuelle de temp\u00e9ratures et de <\/span><span style=\"font-size: small;\">pr\u00e9cipitations relativement faible. Plus \u00e0 l&rsquo;Est, o\u00f9 l&rsquo;influence du Gulf <\/span><span style=\"font-size: small;\">Stream n&rsquo;est plus perceptible, ce sont des climats continentaux qui <\/span><span style=\"font-size: small;\">dominent, avec de grands \u00e9carts annuels de temp\u00e9rature. Enfin, le Sud du <\/span><span style=\"font-size: small;\">continent b\u00e9n\u00e9ficie d&rsquo;un climat M\u00e9diterran\u00e9en, g\u00e9n\u00e9ralement chaud et <\/span><span style=\"font-size: small;\">sec. Un exemple simple de l&rsquo;influence consid\u00e9rable du Gulf Stream : Paris <\/span><\/span><\/span><span style=\"color: #2b2bff;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">est \u00e0 la latitude de Qu\u00e9bec, or Qu\u00e9bec poss\u00e8de un climat bien plus froid <\/span><span style=\"font-size: small;\">que Paris. C&rsquo;est seulement dans l&rsquo;Atlantique Nord que nous pouvons <\/span><span style=\"font-size: small;\">apercevoir des eaux \u00e0 plus de 10\u00b0C au-del\u00e0 du 50<\/span><\/span><span style=\"font-family: ComicSansMS; font-size: small;\">e <\/span><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">parall\u00e8le et presque <\/span><span style=\"font-size: small;\">jusqu&rsquo;au 60<\/span><\/span><span style=\"font-size: small;\"><span style=\"font-family: ComicSansMS;\">e <\/span><span style=\"font-family: ComicSansMS;\">parall\u00e8le. Dans le Pacifique Nord, \u00e0 cette latitude du 60<\/span><span style=\"font-family: ComicSansMS;\">e <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">parall\u00e8le on observe soit de la banquise, soit des eaux tr\u00e8s froides<\/span><span style=\"font-size: small;\">proches de 0\u00b0C.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant10.jpg?resize=700%2C550\" alt=\"\" width=\"700\" height=\"550\" \/><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\">Sch\u00e9ma des temp\u00e9ratures des eaux de l&rsquo;Atlantique Nord<\/span><\/p>\n<p align=\"justify\">\n<p align=\"justify\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant11.jpg?resize=700%2C550\" alt=\"\" width=\"700\" height=\"550\" \/><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS; font-size: small;\"><span style=\"color: #2b2bff;\">Sch\u00e9ma des temp\u00e9ratures des eaux du Pacifique Nord <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Un Gulf Stream plus fort v\u00e9hiculera des eaux plus chaudes vers le <\/span><span style=\"font-size: small;\">Nord, ainsi l&rsquo;oc\u00e9an est plus chaud. Et un oc\u00e9an plus chaud favorise la <\/span><span style=\"font-size: small;\">cyclog\u00e9n\u00e8se (la formation de d\u00e9pressions) \u00e0 cause du fait qu&rsquo;il doit <\/span><span style=\"font-size: small;\">\u00e9vacuer sa chaleur exc\u00e9dentaire et ce par les d\u00e9pressions et cyclones, <\/span><span style=\"font-size: small;\">destructrices de chaleur (un cyclone ne transforme que 5% de sa chaleur <\/span><span style=\"font-size: small;\">captur\u00e9e en \u00e9nergie m\u00e9canique, donc c&rsquo;est un mauvais destructeur de <\/span><span style=\"font-size: small;\">chaleur), ce qui am\u00e8ne \u00e0 un flux de Sud-Ouest (donc chaud et humide) <\/span><span style=\"font-size: small;\">sur l&rsquo;Europe occidentale comme l&rsquo;hiver 2006\/2007 que nous venons de <\/span><span style=\"font-size: small;\">conna\u00eetre.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Au contraire, un oc\u00e9an plus froid am\u00e8ne \u00e0 la formation <\/span><span style=\"font-size: small;\">d&rsquo;anticyclones, et ainsi v\u00e9hiculent dans leur partie Est un flux de Nord, <\/span><span style=\"font-size: small;\">donc froid (pour l&rsquo;h\u00e9misph\u00e8re Nord).<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ainsi tous les courants marins chauds r\u00e9chauffent l&rsquo;atmosph\u00e8re qui <\/span><span style=\"font-size: small;\">est au-dessus d&rsquo;eux et inversement si ce sont des courants froids. Et oui <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">les capacit\u00e9s thermiques de l&rsquo;oc\u00e9an sont telles que les deux premiers <\/span><span style=\"font-size: small;\">m\u00e8tres de la mer \u00ab repr\u00e9sentent \u00bb les m\u00eames capacit\u00e9s thermiques que <\/span><span style=\"font-size: small;\">2000 m\u00e8tres de l&rsquo;atmosph\u00e8re. Et les 10 premiers m\u00e8tres <\/span><span style=\"font-size: small;\">\u00ab repr\u00e9sentent \u00bb la troposph\u00e8re et la stratosph\u00e8re enti\u00e8res !<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">2\u00b0) Les influences des courants temporaires<\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">a) El Nino<\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Quand ce ph\u00e9nom\u00e8ne a lieu, beaucoup de pays sont touch\u00e9s.<\/span><\/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 align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les eaux sont moins chaudes en Indon\u00e9sie, des anticyclones se cr\u00e9ent <\/span><span style=\"font-size: small;\">donc \u00e0 la place des d\u00e9pressions, causant des s\u00e9cheresses en Australie et <\/span><span style=\"font-size: small;\">en Indon\u00e9sie, voir des incendies de for\u00eats dans des zones qui ont <\/span><span style=\"font-size: small;\">d&rsquo;habitude des pr\u00e9cipitations abondantes. Mais les cyclones sont moins <\/span><span style=\"font-size: small;\">nombreux \u00e0 l&rsquo;ouest du Pacifique.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ces eaux qui sont amen\u00e9es de l&rsquo;autre c\u00f4t\u00e9 du Pacifique provoquent <\/span><span style=\"font-size: small;\">une baisse de la pression atmosph\u00e9rique donc une augmentation des <\/span><span style=\"font-size: small;\">pr\u00e9cipitations sur la c\u00f4te-est d&rsquo;Am\u00e9rique du sud (surtout au nord du <\/span><span style=\"font-size: small;\">Br\u00e9sil, au P\u00e9rou), voire d&rsquo;importantes inondations dans des r\u00e9gions <\/span><span style=\"font-size: small;\">habituellement d\u00e9sertiques.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les cyclones affectant la Polyn\u00e9sie sont en augmentation ainsi que les <\/span><span style=\"font-size: small;\">tornades, provoquant des cons\u00e9quences dramatiques. L&rsquo;eau se <\/span><span style=\"font-size: small;\">r\u00e9chauffant elle coupe l&rsquo;upwelling (la remont\u00e9e) de l&rsquo;eau froide et riche <\/span><span style=\"font-size: small;\">en aliments nutritifs, et de nombreuses sortes de poissons migrent vers <\/span><span style=\"font-size: small;\">le P\u00f4le, r\u00e9duisant s\u00e9v\u00e8rement les populations dans cette partie de l&rsquo;oc\u00e9an <\/span><span style=\"font-size: small;\">Pacifique.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">L&rsquo;Afrique du Sud et de l&rsquo;Est, le sud de l&rsquo;Inde, et le Pakistan <\/span><span style=\"font-size: small;\">connaissent aussi des s\u00e9cheresses et les inondations de l&rsquo;Inde sont <\/span><span style=\"font-size: small;\">sporadiques.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Dans l&rsquo;oc\u00e9an Atlantique le nombre d&rsquo;ouragans diminue.<\/span><\/p>\n<p align=\"center\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant12.jpg\" alt=\"\" \/><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Sch\u00e9ma des incidences de El Nino de D\u00e9cembre \u00e0 F\u00e9vrier.<\/span><\/p>\n<p align=\"center\"><span style=\"color: #2b2bff;\"><img data-recalc-dims=\"1\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant13.jpg\" alt=\"\" \/><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Sch\u00e9ma des incidences de El Nino de Juin \u00e0 Ao\u00fbt.<\/span><\/p>\n<p align=\"justify\">\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">En bleu fonc\u00e9 : frais et pluvieux ; en jaune : chaud et sec ; en bleu clair : frais ; en <\/span><span style=\"font-size: small;\">vert fonc\u00e9 : pluvieux ; en vert clair : chaud et pluvieux ; en orange : frais et sec ; en <\/span><span style=\"font-size: small;\">marron : sec ; en rouge : chaud.<\/span><\/span><\/p>\n<p align=\"justify\">b) La Nina<\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">La Ni\u00f1a, un ph\u00e9nom\u00e8ne qui est tout l&rsquo;oppos\u00e9 d&rsquo;El Ni\u00f1o, a donc des <\/span><span style=\"font-size: small;\">cons\u00e9quences oppos\u00e9es.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les eaux sont plus chaudes en Indon\u00e9sie et se r\u00e9chauffent peu \u00e0 peu <\/span><span style=\"font-size: small;\">atteignant 29\u00b0C et le niveau de la mer s&rsquo;\u00e9l\u00e8ve de 40 cm sur les bords <\/span><span style=\"font-size: small;\">ouest du bassin. Cela amplifie les pr\u00e9cipitations au sud-est de l&rsquo;Asie et \u00e0 <\/span><span style=\"font-size: small;\">l&rsquo;est de l&rsquo;Australie et cause d&rsquo;importantes inondations. Les moussons <\/span><span style=\"font-size: small;\">sont aussi anormalement fortes en Inde. L&rsquo;Afrique du Sud conna\u00eet <\/span><span style=\"font-size: small;\">\u00e9galement des pr\u00e9cipitations plus importantes.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Mais les \u00eeles intertropicales du Pacifique Central et de l&rsquo;autre cot\u00e9 <\/span><span style=\"font-size: small;\">du Pacifique : le sud de l\u2019Am\u00e9rique du Nord, le nord du Mexique et la <\/span><span style=\"font-size: small;\">Californie&#8230; connaissent des p\u00e9riodes de s\u00e9cheresses prononc\u00e9es.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ce ph\u00e9nom\u00e8ne climatique augmente le nombre de cyclones dans <\/span><span style=\"font-size: small;\">l&rsquo;Atlantique comme il diminue le cisaillement vertical des vents. En effet, <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">il faut pour un cyclone que les vents soient stables pour une convection <\/span><span style=\"font-size: small;\">haute, forte et stable. Dans le Pacifique, les forces et la trajectoire des <\/span><span style=\"font-size: small;\">temp\u00eates sont diff\u00e9rentes et comme le jet-stream change de latitude, ils <\/span><span style=\"font-size: small;\">sont moins fr\u00e9quents.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Sch\u00e9ma des incidences de La Nina de D\u00e9cembre \u00e0 F\u00e9vrier.<\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">Sch\u00e9ma des incidences de La Nina de Juin \u00e0 Ao\u00fbt.<\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">M\u00eame l\u00e9gende que pr\u00e9c\u00e9demment.<\/span><\/p>\n<p align=\"justify\">3\u00b0) Les autres influences des courants marins.<\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Les courants marins convectifs (circulation thermohaline g\u00e9n\u00e9rale <\/span><span style=\"font-size: small;\">donc) ram\u00e8nent des profondeurs des sels min\u00e9raux indispensables \u00e0 la <\/span><span style=\"font-size: small;\">croissance du phytoplancton (plancton v\u00e9g\u00e9tale) qui est \u00e0 la base de la <\/span><span style=\"font-size: small;\">cha\u00eene alimentaire marine.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">De plus, les oc\u00e9ans sont des \u00e9normes puits de carbone (capable de <\/span><span style=\"font-size: small;\">stocker du CO<\/span><\/span><\/span><span style=\"color: #2b2bff; font-family: ComicSansMS; font-size: small;\">2 <\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">et autres gaz \u00e0 effet de serre pr\u00e9sents dans l&rsquo;air). Plus <\/span><span style=\"font-size: small;\">un oc\u00e9an est froid, plus il capture et stocke facilement. L&rsquo;oc\u00e9an austral <\/span><span style=\"font-size: small;\">repr\u00e9sente 60% de la capture des gaz \u00e0 effet de serre alors qu&rsquo;il <\/span><span style=\"font-size: small;\">repr\u00e9sente moins de 20% de la surface mondiale oc\u00e9ane. Cela est d\u00fb \u00e0 ses <\/span><span style=\"font-size: small;\">temp\u00e9ratures basses.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ainsi les courants marins am\u00e8nent en capturant les gaz \u00e0 effet de <\/span><span style=\"font-size: small;\">serre de l&rsquo;oxyg\u00e8ne provenant des profondeurs. <\/span><span style=\"font-size: small;\">Les courants marins influencent donc le climat mondial, et la cha\u00eene <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">alimentaire marine mondiale. Et par cons\u00e9quent ils influencent l&rsquo;\u00e9conomie <\/span><span style=\"font-size: small;\">et l&rsquo;agriculture des hommes, et donc influencent finalement les hommes.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">III.Des perspectives d&rsquo;avenir.<\/span><\/p>\n<p align=\"justify\">1\u00b0) Le contexte du r\u00e9chauffement climatique<\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Le r\u00e9chauffement climatique est av\u00e9r\u00e9 et n&rsquo;est plus contest\u00e9. Il est <\/span><span style=\"font-size: small;\">appuy\u00e9 par les rapports du GIEC (IPCC en anglais) r\u00e9dig\u00e9s par plus de <\/span><span style=\"font-size: small;\">600 climatologues provenant de tous les pays.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Le rapport Ar4 de F\u00e9vrier 2007 du GIEC indique que les effets sur <\/span><span style=\"font-size: small;\">le climat comporteront une augmentation des s\u00e9cheresses, de pluies <\/span><span style=\"font-size: small;\">torrentielles, du nombre de canicules et cyclones violents, et enfin une <\/span><span style=\"font-size: small;\">\u00e9l\u00e9vation du niveau de l&rsquo;oc\u00e9an.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Selon les hypoth\u00e8ses retenues et les mod\u00e8les employ\u00e9s, les <\/span><span style=\"font-size: small;\">pr\u00e9visions pour les 50 ann\u00e9es \u00e0 venir verraient une augmentation de la <\/span><span style=\"font-size: small;\">temp\u00e9rature de 2 \u00e0 6\u00b0C.<\/span><\/span><\/p>\n<p align=\"justify\">2\u00b0) Quels risques pour les courants marins ?<\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Le GIEC juge pour le XXIe si\u00e8cle comme probable un ralentissement <\/span><span style=\"font-size: small;\">de la circulation thermohaline et comme peu probable son arr\u00eat. Cet arr\u00eat <\/span><span style=\"font-size: small;\">total et d\u00e9finitif est consid\u00e9r\u00e9 comme possible \u00e0 plus long terme. <\/span><span style=\"font-size: small;\">Cet arr\u00eat du Gulf Stream s&rsquo;est d\u00e9j\u00e0 produit dans le pass\u00e9 il y a <\/span><span style=\"font-size: small;\">8200 ans \u00e0 l&rsquo;\u00e9poque du Dryas Recent et il y a 12000 ans.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Il y a 8200 ans, la Terre sort d&rsquo;une p\u00e9riode glaciaire. Ainsi, les <\/span><span style=\"font-size: small;\">glaciers fondent l&rsquo;eau remonte petit \u00e0 petit. Or, il y avait dans l&rsquo;actuelle <\/span><span style=\"font-size: small;\">baie d&rsquo;Hudson un \u00e9norme r\u00e9servoir d&rsquo;eau douce qui avait creus\u00e9 de <\/span><span style=\"font-size: small;\">v\u00e9ritables galeries qu&rsquo;on appelle le lac Agassiz. Ainsi, une quantit\u00e9 <\/span><span style=\"font-size: small;\">importante d&rsquo;eau de fonte en tr\u00e8s peu de temps a engendr\u00e9 l&rsquo;arr\u00eat du <\/span><span style=\"font-size: small;\">Gulf Stream \u00e0 cause d&rsquo;une arriv\u00e9e d&rsquo;eau douce trop importante, qui <\/span><span style=\"font-size: small;\">emp\u00eachait le Gulf Stream d&rsquo;\u00eatre plus lourd et de plonger. On estime <\/span><span style=\"font-size: small;\">cette mont\u00e9e brusque des eaux \u00e0 moins d&rsquo;1,2m. La temp\u00e9rature a chut\u00e9 <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff; font-size: small;\">de 15\u00b0C environ sur le Gro\u00ebnland, et de 5 \u00e0 10\u00b0C sur l&rsquo;Europe occidentale.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Ce processus peut aussi affecter le r\u00e9gime pluviom\u00e9trique de r\u00e9gions <\/span><span style=\"font-size: small;\">tropicales. Des travaux de chercheurs fran\u00e7ais (CNRS, universit\u00e9 Aix-<\/span><span style=\"font-size: small;\">Marseille et Coll\u00e8ge de France) en apportent la preuve, jeudi 22 f\u00e9vrier <\/span><span style=\"font-size: small;\">2006, dans la revue<\/span><\/span><\/span><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\"><span style=\"font-family: ComicSansMS;\">Nature<\/span><span style=\"font-family: ComicSansMS;\">. <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">\u00ab\u00a0Mais lorsqu&rsquo;un refroidissement survient sur <\/span><span style=\"font-size: small;\">l&rsquo;Atlantique nord, la zone, dans laquelle soufflent les aliz\u00e9s, se d\u00e9place <\/span><span style=\"font-size: small;\">vers le sud <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">(on le rappelle, ce sont des vents se d\u00e9pla\u00e7ant d&rsquo;Est en Ouest <\/span><span style=\"font-size: small;\">et circulant nomalement au niveau de l&rsquo;\u00e9quateur), explique Guillaume <\/span><span style=\"font-size: small;\">Leduc, doctorant au Centre d&rsquo;\u00e9tude et de recherche en g\u00e9osciences de <\/span><span style=\"font-size: small;\">l&rsquo;environnement et principal auteur de l&rsquo;\u00e9tude. <\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">Du coup, ces vents se <\/span><span style=\"font-size: small;\">heurtent \u00e0 la cordill\u00e8re des Andes et ne peuvent plus transf\u00e9rer autant <\/span><span style=\"font-size: small;\">d&rsquo;eau vers le Pacifique.\u00a0\u00bb <\/span><\/span><\/span><span style=\"font-family: ComicSansMS;\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">L&rsquo;analyse de s\u00e9diments pr\u00e9lev\u00e9s \u00e0 l&rsquo;ouest de <\/span><span style=\"font-size: small;\">l&rsquo;isthme de Panama montre en effet que, lorsque le froid s&rsquo;installe sur le <\/span><span style=\"font-size: small;\">nord de l&rsquo;Atlantique, la salinit\u00e9 augmente dans le Pacifique, signe d&rsquo;une<\/span><span style=\"font-size: small;\">r\u00e9duction des pluies.<\/span><\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Autre cons\u00e9quence : l&rsquo;eau de pluie d\u00e9vers\u00e9e \u00e0 l&rsquo;est de la cordill\u00e8re des <\/span><span style=\"font-size: small;\">Andes revient, par ruissellement, \u00e0 son point de d\u00e9part, c&rsquo;est-\u00e0-dire dans <\/span><span style=\"font-size: small;\">l&rsquo;Atlantique. Du coup, la salinit\u00e9 de cet oc\u00e9an se r\u00e9duit ; donc ses <\/span><span style=\"font-size: small;\">courants ralentissent plus encore et l&rsquo;Europe du Nord se refroidit un peu <\/span><span style=\"font-size: small;\">plus, etc. Ce processus est en somme un cercle vicieux.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff;\"><span style=\"font-size: small;\">Des mesures satellitaires ont r\u00e9v\u00e9l\u00e9 l&rsquo;existence d&rsquo;un r\u00e9seau de lacs <\/span><span style=\"font-size: small;\">sous la calotte antarctique, plus vaste et dynamique que pr\u00e9vu, qui <\/span><span style=\"font-size: small;\">pourrait jouer un r\u00f4le-cl\u00e9 dans le rythme et le volume des d\u00e9versements <\/span><span style=\"font-size: small;\">de glace dans l&rsquo;oc\u00e9an. Cette recherche montre pour la premi\u00e8re fois que <\/span><span style=\"font-size: small;\">les eaux se trouvant sous les glaces de l&rsquo;Antarctique sont stock\u00e9es dans <\/span><span style=\"font-size: small;\">des r\u00e9servoirs reli\u00e9s entre eux dont elles peuvent sortir ou entrer <\/span><span style=\"font-size: small;\">rapidement, expliquent des glaciologues dont les travaux paraissent dans <\/span><span style=\"font-size: small;\">la revue Science, dat\u00e9e du 15 f\u00e9vrier 2006. Ces mouvements pourraient <\/span><span style=\"font-size: small;\">peut-\u00eatre jouer un r\u00f4le majeur pour d\u00e9terminer le rythme auquel les <\/span><span style=\"font-size: small;\">glaces antarctiques se d\u00e9tachent du continent, souligne Helen Fricker, <\/span><span style=\"font-size: small;\">glaciologue. \u00ab Nous ne nous rendions pas compte que l&rsquo;eau sous les glaces <\/span><span style=\"font-size: small;\">antarctiques se d\u00e9pla\u00e7ait en d&rsquo;aussi grands volumes et aussi rapidement\u00bb, <\/span><span style=\"font-size: small;\">ajoute-t-elle. Depuis que le satellite de la Nasa a commenc\u00e9 ses mesures&#8230;<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"color: #2b2bff; font-size: small;\">A suivre dans la partie 3&#8230; <a href=\"http:\/\/www.laterredufutur.com\/html\/modules.php?name=News&amp;file=article&amp;sid=473\">ICI<\/a><\/span><\/p>\n<p><span style=\"font-family: ComicSansMS;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-family: ComicSansMS;\"><span style=\"font-size: small;\">sources\u00a0:<\/span><\/span><\/span><\/span><\/span><\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/flynetweb.free.fr\/index.htm<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/fr.wikipedia.org\/wiki\/courant-marin.<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/fr.wikipedia.org\/wiki\/force-de-coriolis<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/www.ens-lyon.fr\/Planet-Terre\/Infosciences\/Climats\/Dynam-atmos\/courscoriolis<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/www.ifremer.fr\/aei2006\/presentation\/T1S3\/aei2006_16_58.pdf<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/www.mercator-ocean.fr\/html\/<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/la.climatologie.free.fr\/sommaire.htm<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; http:\/\/laterredufutur.com\/html<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">LIVRES :<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; Petit atlas du climat, Laure Ch\u00e9mery<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; Plan\u00e8te oc\u00e9ane (pp 47-55)<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">Dictionnaires :<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; Le Petit Larousse illustr\u00e9, \u00e9dition 2007<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; Le Robert, \u00e9dition 2007<\/span><\/p>\n<p align=\"left\"><span style=\"font-size: small;\">&gt; Encyclop\u00e9die Universalis, \u00e9dition 2000<\/span><\/p>\n<p>&nbsp;<\/p>\n<p class=\"bawpvc-ajax-counter\" data-id=\"3936\">(1124)<\/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>Voici un dossier, en\u00a04 parties qui seront publi\u00e9es sur la Terre du Futur, transmis par Fifi321fth (Thomas), pass\u00e9 au lyc\u00e9e&#8230;<\/p>\n","protected":false},"author":1,"featured_media":3930,"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":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[20,23],"tags":[395,41,1028,396,703,241,1523],"class_list":["post-3936","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-climat","category-circulation-oceanique","tag-atlantique-nord","tag-climat","tag-gs","tag-gulf-stream","tag-impact","tag-ocean","tag-rapport","wpcat-20-id","wpcat-23-id"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2015\/04\/Courants-Marins.gif?fit=250%2C172&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p631RN-11u","jetpack-related-posts":[{"id":3929,"url":"https:\/\/www.laterredufutur.com\/accueil\/dossier-n-1-les-courants-marins\/","url_meta":{"origin":3936,"position":0},"title":"Dossier N\u00b0 1 : Les Courants Marins","author":"Admin","date":"1 avril 2007","format":false,"excerpt":"dossier, en\u00a04 parties qui seront publi\u00e9es sur la Terre du Futur, transmis par Fifi321fth (Thomas), pass\u00e9 au lyc\u00e9e Sacr\u00e9-Coeur \u00e0 Reims. Thomas L., Enguerran D., Juliette M. Dossier Exclusif sur les Courants Marins et de ce qui en r\u00e9sulte... Ici\u00a01 ere partie.. SOMMAIRE des\u00a04 parties qui seront publi\u00e9es en\u00a04 articles\u2026","rel":"","context":"Dans &quot;Climat&quot;","block_context":{"text":"Climat","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/climat\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant1.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":3949,"url":"https:\/\/www.laterredufutur.com\/accueil\/dossier-n4-les-courants-marins\/","url_meta":{"origin":3936,"position":1},"title":"Dossier N\u00b04 : Les Courants Marins","author":"Admin","date":"15 avril 2007","format":false,"excerpt":"Voici un dossier, en\u00a04 parties qui seront publi\u00e9es sur la Terre du Futur, transmis par Fifi321fth (Thomas), pass\u00e9 au lyc\u00e9e Sacr\u00e9-Coeur \u00e0 Reims. Thomas L., Enguerran D., Juliette M. Dossier Exclusif sur les Courants Marins et de ce qui en r\u00e9sulte. Ici\u00a04 eme partie... Sch\u00e9mas de la salinit\u00e9 de diff\u00e9rents\u2026","rel":"","context":"Dans &quot;Climat&quot;","block_context":{"text":"Climat","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/climat\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant19.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant19.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant19.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":3942,"url":"https:\/\/www.laterredufutur.com\/accueil\/dossier-n3-les-courants-marins\/","url_meta":{"origin":3936,"position":2},"title":"Dossier N\u00b03 : Les Courants Marins","author":"Admin","date":"10 avril 2007","format":false,"excerpt":"Voici un dossier, en\u00a04 parties qui seront publi\u00e9es sur la Terre du Futur, transmis par Fifi321fth (Thomas), pass\u00e9 au lyc\u00e9e Sacr\u00e9-Coeur \u00e0 Reims. Thomas L., Enguerran D., Juliette M. Dossier Exclusif sur les Courants Marins et de ce qui en r\u00e9sulte. Ici 3 eme partie. Des mesures satellitaires ont r\u00e9v\u00e9l\u00e9\u2026","rel":"","context":"Dans &quot;Climat&quot;","block_context":{"text":"Climat","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/climat\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant15.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant15.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/laterredufutur.com\/spaw\/images\/courant15.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":15312,"url":"https:\/\/www.laterredufutur.com\/accueil\/les-courants-marins-mecanisme-et-role-dans-les-variations-climatiques\/","url_meta":{"origin":3936,"position":3},"title":"Les Courants Marins, m\u00e9canisme et r\u00f4le dans les variations climatiques","author":"Admin","date":"31 mai 2017","format":false,"excerpt":"Un courant marin est un mouvement d'eau de mer r\u00e9gulier, continu et cyclique. Ce type de mouvement est d\u00fb aux effets combin\u00e9s du vent, de la force de Coriolis, et de diff\u00e9rences de temp\u00e9rature, densit\u00e9 et salinit\u00e9 ; ainsi qu'\u00e9videmment aux contours des continents mais aussi aux reliefs de profondeur\u2026","rel":"","context":"Dans &quot;Courants Marins&quot;","block_context":{"text":"Courants Marins","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/circulation-oceanique\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2017\/05\/inondations-13000ans-atlantique-nord-gulfstream.jpg?fit=480%2C360&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":28000,"url":"https:\/\/www.laterredufutur.com\/accueil\/pourquoi-la-temperature-des-oceans-varie-t-elle\/","url_meta":{"origin":3936,"position":4},"title":"Pourquoi la temp\u00e9rature des oc\u00e9ans varie-t-elle ?","author":"Admin","date":"24 avril 2026","format":false,"excerpt":"Les oc\u00e9ans couvrent plus de 70 % de la surface de la Terre. Ils jouent un r\u00f4le fondamental dans le climat mondial, en stockant et redistribuant la chaleur. Mais leur temp\u00e9rature n\u2019est pas uniforme : elle varie selon de nombreux facteurs, parfois visibles, parfois invisibles. 1. Le Soleil : la\u2026","rel":"","context":"Dans &quot;Courants Marins&quot;","block_context":{"text":"Courants Marins","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/circulation-oceanique\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2026\/04\/vague-ocean-coucher-de-soleil.jpg?fit=1200%2C800&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2026\/04\/vague-ocean-coucher-de-soleil.jpg?fit=1200%2C800&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2026\/04\/vague-ocean-coucher-de-soleil.jpg?fit=1200%2C800&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2026\/04\/vague-ocean-coucher-de-soleil.jpg?fit=1200%2C800&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2026\/04\/vague-ocean-coucher-de-soleil.jpg?fit=1200%2C800&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":22226,"url":"https:\/\/www.laterredufutur.com\/accueil\/le-changement-du-climat-modifie-fondamentalement-la-structure-des-oceans-de-notre-monde\/","url_meta":{"origin":3936,"position":5},"title":"Le changement du climat modifie \u00ab\u00a0fondamentalement\u00a0\u00bb la structure des oc\u00e9ans de notre monde","author":"Admin","date":"25 mars 2021","format":false,"excerpt":"Le changement climatique a entra\u00een\u00e9 des changements majeurs dans la stabilit\u00e9 des oc\u00e9ans plus rapidement qu'on ne le pensait auparavant, selon une \u00e9tude publi\u00e9e mercredi 24 mars 2021, sonnant l'alarme sur son r\u00f4le de thermostat mondial et la vie marine qu'il soutient. La recherche publi\u00e9e dans la revue Nature s'est\u2026","rel":"","context":"Dans &quot;Climat&quot;","block_context":{"text":"Climat","link":"https:\/\/www.laterredufutur.com\/accueil\/sujets\/climat\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/03\/ocean-courant-marin-atlantique.jpg?fit=1024%2C415&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/03\/ocean-courant-marin-atlantique.jpg?fit=1024%2C415&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/03\/ocean-courant-marin-atlantique.jpg?fit=1024%2C415&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/www.laterredufutur.com\/accueil\/wp-content\/uploads\/2021\/03\/ocean-courant-marin-atlantique.jpg?fit=1024%2C415&ssl=1&resize=700%2C400 2x"},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/3936","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=3936"}],"version-history":[{"count":1,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/3936\/revisions"}],"predecessor-version":[{"id":3937,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/posts\/3936\/revisions\/3937"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media\/3930"}],"wp:attachment":[{"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/media?parent=3936"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/categories?post=3936"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laterredufutur.com\/accueil\/wp-json\/wp\/v2\/tags?post=3936"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}