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Le climat dans l’avenir </a> </li> </ul> <button class="btn btn-sm btn-universalis" data-bs-toggle="collapse" data-bs-target="#free-toc" aria-expanded="false" title="Afficher / masquer le sommaire"> <i aria-hidden="true" class="fa fa-fw fa-eye"></i> Sommaire </button> </div> <h1 class="mb-1"> <strong>CLIMATS </strong><span class="rm">(notions de base)</span> </h1> <ul class="pagination justify-content-center public-links "><li class="page-item active"><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 1" class="page-link" title="Abonnez-vous" data-loaded="true">1</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 2" class="page-link" title="Abonnez-vous" data-loaded="true">2</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 3" class="page-link" title="Abonnez-vous" data-loaded="true">3</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 4" class="page-link" title="Abonnez-vous" data-loaded="true">4</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 5" class="page-link" title="Abonnez-vous" data-loaded="true">5</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 6" class="page-link" title="Abonnez-vous" data-loaded="true">6</a></li></ul><p class="text-sm text-muted mb-1">Article modifié le <time datetime="2025-01-29"> 29/01/2025 </time></p><div class="content paged type-article" ><div class="block_1" data-ucode="yMI15035_0"><i class="anchor" id="yMI15035_0"></i><p>Le climat terrestre a, de tout temps, été sujet à des variations naturelles. Ainsi, les deux derniers millions d’années ont vu plusieurs glaciations. Mais l’homme, depuis quelques dizaines d’années, modifie cet équilibre fragile en provoquant un réchauffement planétaire rapide sans précédent. Pour mieux comprendre l’impact de ce réel bouleversement, il est important de tenter de comprendre les phénomènes qui définissent les climats, les facteurs qui les gouvernent ainsi que leur répartition à la surface du globe.</p><div class="clearfix"></div></div><div class="block_1" data-ucode="yMI15035_1"><i class="anchor" id="yMI15035_1"></i><h2>Les climats du passé</h2><p>Les climats sur Terre ont beaucoup varié dans le passé. Les <a data-bs-toggle="popover" data-bs-content="On appelle forage l'ensemble des opérations permettant le creusement de trous généralement verticaux. L'utilisation principale des forages est la reconnaissance et l' exploitation des gisements de pétrole ou de gaz naturel . Les autres utilisations, qui sont nombreuses, comprennent notamment : les forages géologiques ou géophysiques pour la reconnaissance des gisements de minerais ; ..." title="Article : FORAGES" href="/encyclopedie/forages/">forages</a> dans l’Antarctique, les pollens et les fossiles, des documents historiques, etc., tous en témoignent. À l’origine de ces variations se trouvent notamment la quantité d’énergie émise par le <a data-bs-toggle="popover" data-bs-content="Le fait que le Soleil ne soit qu'une étoile parmi les quelque 200 milliards – de toutes tailles, masses et couleurs – qu’abrite notre Galaxie, lui conférant ainsi le statut d'étoile « banale », ne doit pas faire oublier que c'est l’étoile de notre système solaire . Il lui fournit lumière et énergie. Passé, présent et futur lointain de la Terre dépendent essentiell..." title="Article : SOLEIL" href="/encyclopedie/soleil/">Soleil</a>, la position Terre-Soleil relative ou encore la <a data-bs-toggle="popover" data-bs-content="La tectonique des plaques est formulée de façon synthétique dans deux articles publiés en 1968, l'un signé par l'Américain W. Jason Morgan, l'autre par le Français Xavier Le Pichon. Ces deux chercheurs s'étaient « appuyés sur les épaules de géants », parmi lesquels John Tuzo Wilson, qui avait proposé la notion de faille transformante. Ce dernier écrivit en 1969 cet article, q..." title="Article : DÉRIVE DES CONTINENTS" href="/encyclopedie/derive-des-continents/">dérive des continents</a>.</p><div class="block_2" data-ucode="yMI15035_1_0"><i class="anchor" id="yMI15035_1_0"></i><h3>Les causes des variations climatiques</h3><p>Périodes chaudes, périodes froides, glaciations : le climat à la surface de la Terre a constamment varié au cours des temps. On peut distinguer trois types de causes aux variations climatiques.</p><p>En premier lieu, le climat est directement fonction de la quantité d’énergie solaire reçue par la Terre. Or l’activité du Soleil est sujette à des fluctuations. Elle a évolué depuis 4,5 milliards d’années ; à cette époque, l’énergie solaire était inférieure de 25 p. 100 à celle d’aujourd’hui. Elle connaît aussi des variations cycliques, liées notamment à l’existence plus ou moins prononcée de taches et de protubérances (éruptions) solaires. Par ailleurs, la position relative Terre-Soleil n’est pas constante. Tout d’abord, l’orbite de la Terre autour du Soleil évolue sur une période d’environ 100 000 ans d’une forme presque circulaire à une forme très elliptique. Ensuite, l’inclinaison de l’axe de rotation de la Terre par rapport au plan orbital varie progressivement tous les 41 000 ans. Enfin, cet axe de rotation décrit en 26 000 ans un cône, appelé cône de précession. Ces trois paramètres modifient la distance Terre-Soleil, et donc la quantité d’énergie solaire reçue.</p><p> La deuxième cause des variations climatiques est liée à la dérive des continents. La position et la part relative des continents et des océans changent, ce qui modifie les processus d’absorption, de réflexion et d’échange d’énergie ainsi que les courants océaniques et la circulation atmosphérique. Pour ne donner qu’un exemple, le <a data-bs-toggle="popover" data-bs-content="Le Sahara est le plus grand désert chaud du monde. Occupant presque tout le nord de l'Afrique, il mesure environ 4 800 kilomètres d'est en ouest et entre 1 300 et 1 900 kilomètres du nord au sud, soit une superficie totale de près de 8 600 000 kilomètres carrés. Il se prolonge au-delà de la mer Rouge et est appelé alors désert saharo-arabique, étiré sur 7 500 kilom..." title="Article : SAHARA" href="/encyclopedie/sahara/">Sahara</a> se trouvait en région polaire Sud il y a 450 millions d’années et a été recouvert par une calotte glaciaire.</p><div class="clearfix"></div><div class="media-container float-md-start me-3 col-md-3 text-center"><figure class="figure text-center w-100 mb-0 p-1" style="position: relative"><a data-ucode="VI000040" data-showMediaPlayer="1" class="protected media-reference-copy " title="Média : Mouvement des planètes" href="/media/mouvement-des-planetes-vi000040/"><img id="VI000040" loading="lazy" src="/typo3temp/assets/_processed_/0/5/csm_vi000040_423a64908a.webp" class="figure-img rounded mx-auto media_resized" alt="Mouvement des planètes - crédits : Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française." data-description="Principaux mouvements: rotation, révolution, précession et nutation.Les planètes, comme le reste de la matière de l'Univers, sont soumises aux forces de gravitation exercées par les autres corps présents dans l'espace. Elles exécutent une série de mouvements déterminés autour d'une étoile centrale,…" data-copyright="Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française." width="" height="" /></a><figcaption class="figure-caption"><p class="m-0 mt-1 fw-bold text-gray-700 text-truncate"> Mouvement des planètes </p><p class="m-0 copyright text-sm text-gray-700 text-truncate"> Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française. </p></figcaption></figure></div><p>Enfin, la troisième cause est liée aux modifications de la composition de l’atmosphère, laquelle joue un rôle dans la transformation et la redistribution de l’énergie solaire. Les constituants de l’atmosphère ont varié au cours du temps. Les gaz à effet de <a data-bs-toggle="popover" data-bs-content="Dans son sens le plus large, une serre désigne un dispositif établi pour modifier à moindres frais l'action des facteurs naturels et l'adapter au mieux aux besoins des plantes . Par sa présence, la serre crée, à partir du milieu naturel, un milieu semi-artificiel permettant de cultiver des végétaux qui, sans elle, ne pousseraient pas ou ne monteraient pas à fleurs et à fruits , ou pous..." title="Article : SERRE" href="/encyclopedie/serre/">serre</a> (vapeur d’eau, dioxyde de <a data-bs-toggle="popover" data-bs-content="Le carbone est l'élément chimique non métallique de symbole C et de numéro atomique 6. Il est présent dans de nombreux composés naturels : gaz carbonique de l'atmosphère, roches calcaires , combustibles (gaz, pétrole, charbons minéraux). C'est de plus un constituant fondamental de la matière vivante. Par la photosynthèse , les plantes convertissent le gaz carbonique de l'air en hyd..." title="Article : CARBONE" href="/encyclopedie/carbone/">carbone</a>, <a data-bs-toggle="popover" data-bs-content="Formule brute : CH 4. Masse moléculaire : 16,04 g. Masse spécifique : 0,716 8 g/l. Point d'ébullition : — 161,5 0 C. Point de fusion : — 184 0 C. Le méthane est un hydrocarbure saturé, le plus simple des alcanes . C'est un gaz incolore, d'odeur légèrement alliacée, qui a été découvert en 1778 par A. Volta.. Les quatre liaisons C—H du méthane sont de longueur égale..." title="Article : MÉTHANE" href="/encyclopedie/methane/">méthane</a>, etc.) étaient prépondérants pendant les deux premiers milliards d’années, créant au sol une température plus élevée. Par ailleurs, les <a data-bs-toggle="popover" data-bs-content="Jets de gaz, projections de magma, cendres, lapilli, blocs, ponces et scories, coulées et fontaines de lave, lahars, écoulements pyroclastiques, bombes volcaniques, panaches pliniens, nuées ardentes... les éruptions volcaniques peuvent être définies comme la dispersion à la surface de la Terre de différents matériaux géologiques d'origine magmatique. Comprendre les éruptions volcaniq..." title="Article : ÉRUPTIONS VOLCANIQUES" href="/encyclopedie/eruptions-volcaniques/">éruptions volcaniques</a>, en projetant de fortes quantités de gaz et de poussières, voilent la lumière solaire et peuvent provoquer un « hiver volcanique ».</p><div class="clearfix"></div></div><div class="block_2" data-ucode="yMI15035_1_1"><i class="anchor" id="yMI15035_1_1"></i><h3>Les moyens d’étude</h3><p>Il existe de nombreux « témoins » des variations climatiques. Archives et documents historiques (nombre de jours de gel, date et prix des récoltes, etc.) donnent des informations sur le climat des derniers siècles.</p><p>La <a data-bs-toggle="popover" data-bs-content="Dans les régions à climat saisonnier contrasté, les espèces ligneuses pérennes, dont les arbres, génèrent annuellement une couche de bois « anneau » ou « cerne » de croissance qui participe à leur accroissement en diamètre. L'épaisseur d'un cerne est la résultante d'un ensemble de facteurs intrinsèques (spécifiques et géométriques) et extrinsèques (écologiques : substra..." title="Article : DENDROCLIMATOLOGIE" href="/encyclopedie/dendroclimatologie/">dendroclimatologie</a> (étude des cernes de croissance des arbres) renseigne sur les années humides et celles de sécheresse, et s’applique sur les derniers 10 000 ans.</p><p>On utilise aussi la mesure du rapport entre les deux isotopes de l’oxygène <sup>16</sup>O et <sup>18</sup>O contenus dans les glaces polaires, les coraux, les fossiles, etc., rapport qui varie en fonction de la température de l’époque. Appliquées aux forages des calottes polaires, les mesures<a href="javascript:" title="Lire la suite" class="read-more ms-1">[...]</a></p></div></div><div class="clearfix"></div></div><ul class="pagination justify-content-center public-links "><li class="page-item active"><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 1" class="page-link" title="Abonnez-vous" data-loaded="true">1</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 2" class="page-link" title="Abonnez-vous" data-loaded="true">2</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 3" class="page-link" title="Abonnez-vous" data-loaded="true">3</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 4" class="page-link" title="Abonnez-vous" data-loaded="true">4</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 5" class="page-link" title="Abonnez-vous" data-loaded="true">5</a></li><li class="page-item "><a href="/abonnement" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="page 6" class="page-link" title="Abonnez-vous" data-loaded="true">6</a></li></ul><div class="folio-block"><p class="folio-block-title text-center text-uc"><strong>La suite de cet article est accessible aux abonnés</strong></p><ul class="list-unstyled"><li><i class="fa fa-fw fa-check-circle"></i> Des contenus variés, complets et fiables</li><li><i class="fa fa-fw fa-check-circle"></i> Accessible sur tous les écrans</li><li><i class="fa fa-fw fa-check-circle"></i> Pas de publicité</li></ul><p class="text-center"><a href="/abonnement/" class="btn btn-cta text-uc" id="folio-button" data-matomo-category="Article" data-matomo-name="Folio" data-matomo-value="Block bottom">Découvrez nos offres </a></p><p class="text-center text-sm"> Déjà abonné ? <a href="/identification/" id="folio-login">Se connecter</a></p></div><div id="ad_mpuslot" class="pub-container text-center"><div class="pub-placeholder"></div></div><section class="mt-3 mb-5"><i class="anchor" id="MI15035_AUTHORS"></i><p class="title-minor">Écrit par</p><ul class="list-group"><li class="list-group-item"><strong> Encyclopædia Universalis</strong> : services rédactionnels de l'Encyclopædia Universalis</li></ul></section><section class="mb-5"><div class="text-center mb-3 d-print-none"><a class="d-inline-flex flex-row justify-content-center align-items-center btn btn-light btn-large text-start" title="Carte mentale : CLIMATS (notions de base)" href="/carte-mentale/climats-notions-de-base/"><i class="fa fa-sitemap fa-rotate-270 me-1 fs-1 text-universalis"></i><p class="m-0"><strong class="fs-4">Carte mentale</strong><br /> Élargissez votre recherche dans Universalis </p></a></div></section> <section class="mb-5 article-classification" data-print-label="la classification" data-print-target=".article-classification"> <i class="anchor" id="yMI15035_ROOT_LINES"></i> <p class="title-minor">Classification</p> <nav aria-label="Classification 1"> <ol class="breadcrumb"> <li class="breadcrumb-item"> <a title="Classification : Sciences de la Terre" href="/classification/sciences-de-la-terre/"> Sciences de la Terre </a> </li> <li class="breadcrumb-item active" data-dc-subject="Climatologie"> <a title="Classification : Climatologie" href="/classification/sciences-de-la-terre/climatologie/"> Climatologie </a> </li> </ol> </nav> <nav aria-label="Classification 2"> <ol class="breadcrumb"> <li class="breadcrumb-item"> <a title="Classification : Sciences de la Terre" href="/classification/sciences-de-la-terre/"> Sciences de la Terre </a> </li> <li class="breadcrumb-item"> <a title="Classification : Climatologie" href="/classification/sciences-de-la-terre/climatologie/"> Climatologie </a> </li> <li class="breadcrumb-item"> <a title="Classification : Variations climatiques" href="/classification/sciences-de-la-terre/climatologie/variations-climatiques/"> Variations climatiques </a> </li> <li class="breadcrumb-item active" data-dc-subject="Paléoclimatologie"> <a title="Classification : Paléoclimatologie" href="/classification/sciences-de-la-terre/climatologie/variations-climatiques/paleoclimatologie/"> Paléoclimatologie </a> </li> </ol> </nav> <nav aria-label="Classification 3"> <ol class="breadcrumb"> <li class="breadcrumb-item"> <a title="Classification : Environnement" href="/classification/environnement/"> Environnement </a> </li> <li class="breadcrumb-item"> <a title="Classification : Dégradation de l'environnement" href="/classification/environnement/degradation-de-l-environnement/"> Dégradation de l'environnement </a> </li> <li class="breadcrumb-item"> <a title="Classification : Changements de l'environnement global" href="/classification/environnement/degradation-de-l-environnement/changements-de-l-environnement-global/"> Changements de l'environnement global </a> </li> <li class="breadcrumb-item active" data-dc-subject="Effet de serre et réchauffement climatique"> <a title="Classification : Effet de serre et réchauffement climatique" href="/classification/environnement/degradation-de-l-environnement/changements-de-l-environnement-global/effet-de-serre-et-rechauffement-climatique/"> Effet de serre et réchauffement climatique </a> </li> </ol> </nav> </section> <section class="mb-5 d-print-none"> <i class="anchor" id="yMI15035_MEDIAS"></i> <p class="title-minor">Médias</p> <div class="row"> <div class="col-12 col-md-4 text-center p-1"> <figure class="figure text-center w-100 mb-0 p-1" style="position: relative"> <a data-ucode="VI000040" data-showMediaPlayer="1" class="protected media-reference-copy " title="Média : Mouvement des planètes" href="/media/mouvement-des-planetes-vi000040/"> <img id="VI000040" loading="lazy" src="/typo3temp/assets/_processed_/0/5/csm_vi000040_423a64908a.webp" class="figure-img rounded mx-auto media_resized" alt="Mouvement des planètes - crédits : Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française." data-description="Principaux mouvements: rotation, révolution, précession et nutation.Les planètes, comme le reste de la matière de l'Univers, sont soumises aux forces de gravitation exercées par les autres corps présents dans l'espace. Elles exécutent une série de mouvements déterminés autour d'une étoile centrale,…" data-copyright="Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française." width="" height="" /> </a> <figcaption class="figure-caption"> <p class="m-0 mt-1 fw-bold text-gray-700 text-truncate"> Mouvement des planètes </p> <p class="m-0 copyright text-sm text-gray-700 text-truncate"> Planeta Actimedia S.A.© Encyclopædia Universalis France pour la version française. </p> </figcaption> </figure> </div> <div class="col-12 col-md-4 text-center p-1"> <figure class="figure text-center w-100 mb-0 p-1" style="position: relative"> <a data-ucode="DE050231" data-showMediaPlayer="1" class="protected media-reference-copy " title="Média : Évolution de la température moyenne à la surface de la Terre depuis sa formation" href="/media/evolution-de-la-temperature-moyenne-a-la-surface-de-la-terre-depuis-sa-formation-de050231/"> <img id="DE050231" loading="lazy" src="/typo3temp/assets/_processed_/1/d/csm_de050231_1e570ccf5f.webp" class="figure-img rounded mx-auto media_resized" alt="Évolution de la température moyenne à la surface de la Terre depuis sa formation - crédits : Encyclopædia Universalis France" data-description="Ce diagramme met en évidence deux glaciations au Précambrien, deux autres au Primaire, un réchauffement progressif pendant le Secondaire, un lent refroidissement tout au long du Tertiaire qui s'achève au Quaternaire par quatre glaciations principales." data-copyright="Encyclopædia Universalis France" width="1998" height="1829" /> </a> <figcaption class="figure-caption"> <p class="m-0 mt-1 fw-bold text-gray-700 text-truncate"> Évolution de la température moyenne à la surface de la Terre depuis sa formation </p> <p class="m-0 copyright text-sm text-gray-700 text-truncate"> Encyclopædia Universalis France </p> </figcaption> </figure> </div> <div class="col-12 col-md-4 text-center p-1"> <figure class="figure text-center w-100 mb-0 p-1" style="position: relative"> <a data-ucode="PH041390" data-showMediaPlayer="1" class="protected media-reference-copy " title="Média : Comparaison entre l'extension des glaces aujourd'hui et à l'époque de la dernière glaciation" href="/media/comparaison-entre-lextension-des-glaces-aujourdhui-et-a-lepoque-de-la-derniere-glaciation-ph041390/"> <img id="PH041390" loading="lazy" src="/typo3temp/assets/_processed_/1/7/csm_ph041390_4d190bcf24.webp" class="figure-img rounded mx-auto media_resized" alt="Comparaison entre l'extension des glaces aujourd'hui et à l'époque de la dernière glaciation - crédits : Living Earth" data-description=""L'ère quaternaire, qui a débuté il y a 1,87 million d'années et qui se poursuit aujourd'hui, a connu quatre glaciations principales. La dernière s'est déroulée entre . 80 000 et . 10 000. À son maximum, il y a 20 000 ans, une calotte de glace de plusieurs milliers de mètres d'épaisseur recouvrait…" data-copyright="Living Earth" width="800" height="379" /> </a> <figcaption class="figure-caption"> <p class="m-0 mt-1 fw-bold text-gray-700 text-truncate"> Comparaison entre l'extension des glaces aujourd'hui et à l'époque de la dernière glaciation </p> <p class="m-0 copyright text-sm text-gray-700 text-truncate"> Living Earth </p> </figcaption> </figure> </div> </div> <div class="text-center"> <a class="btn btn-sm btn-primary" rel="related" href="/medias/climats-notions-de-base/"> Afficher les 10 médias de l'article <span class="rg">CLIMATS </span><span class="rm">(notions de base)</span> <i aria-hidden="true" class="fa fa-fw fa-chevron-right"></i> </a> </div> </section> <section class="mb-5 d-print-none article-indexes learn-more"> <i class="anchor" id="yMI15035_INDEXES"></i> <p class="title-minor">Voir aussi</p> <ul class="list-inline list-inline-bullet"> <li class="list-inline-item m-1"> <a title="Index : RAYONNEMENT SOLAIRE" href="/index/rayonnement-solaire/"> <span class="rg">RAYONNEMENT SOLAIRE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CIRCULATION ATMOSPHÉRIQUE GÉNÉRALE" href="/index/circulation-atmospherique-generale/"> <span class="rg">CIRCULATION ATMOSPHÉRIQUE GÉNÉRALE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : TEMPÉRATURE, météorologie et climatologie" href="/index/temperature-meteorologie-et-climatologie/"> <span class="rg">TEMPÉRATURE, </span><em class="it">météorologie et climatologie</em> </a> </li> <li class="list-inline-item m-1"> <a title="Index : ÉNERGÉTIQUE TRANSFERT, géophysique" href="/index/transfert-energetique-geophysique/"> <span class="rg">ÉNERGÉTIQUE </span><span class="pc">TRANSFERT, </span><em class="it">géophysique</em> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMATS" href="/index/climats/"> <span class="rg">CLIMATS</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMATS ARIDES" href="/index/climats-arides/"> <span class="rg">CLIMATS ARIDES</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : FROIDS CLIMATS" href="/index/climats-froids/"> <span class="rg">FROIDS </span><span class="pc">CLIMATS</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : GLACIATIONS QUATERNAIRES" href="/index/glaciations-quaternaires/"> <span class="rg">GLACIATIONS QUATERNAIRES</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : COURANTS MARINS" href="/index/courants-marins/"> <span class="rg">COURANTS MARINS</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : ALTITUDE" href="/index/altitude/"> <span class="rg">ALTITUDE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : GLACIOLOGIE" href="/index/glaciologie/"> <span class="rg">GLACIOLOGIE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMAT CONTINENTAL" href="/index/climat-continental/"> <span class="rg">CLIMAT CONTINENTAL</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMAT OCÉANIQUE" href="/index/climat-oceanique/"> <span class="rg">CLIMAT OCÉANIQUE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CONTINENT" href="/index/continent/"> <span class="rg">CONTINENT</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CHANGEMENT CLIMATIQUE" href="/index/changement-climatique/"> <span class="rg">CHANGEMENT CLIMATIQUE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMATIQUES VARIATIONS" href="/index/variations-climatiques/"> <span class="rg">CLIMATIQUES </span><span class="pc">VARIATIONS</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : RÉCHAUFFEMENT CLIMATIQUE" href="/index/rechauffement-climatique/"> <span class="rg">RÉCHAUFFEMENT CLIMATIQUE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : GAZ À EFFET DE SERRE" 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<span class="rg">CARBONIQUE </span><span class="pc">GAZ </span><span class="rm">ou </span><span class="rg">DIOXYDE DE CARBONE</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : ÉNERGIE FOSSILE ou COMBUSTIBLES FOSSILES" href="/index/energie-fossile-combustibles-fossiles/"> <span class="rg">ÉNERGIE FOSSILE </span><span class="rm">ou </span><span class="rg">COMBUSTIBLES FOSSILES</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : CLIMAT MÉDITERRANÉEN" href="/index/climat-mediterraneen/"> <span class="rg">CLIMAT MÉDITERRANÉEN</span> </a> </li> <li class="list-inline-item m-1"> <a title="Index : ÉNERGIE SOLAIRE, physique du globe" href="/index/energie-solaire-physique-du-globe/"> <span class="rg">ÉNERGIE SOLAIRE, </span><em class="it">physique du globe</em> </a> </li> </ul> </section> </div> <div class="col-lg-4 col-xl-3 px-0 d-none d-lg-block side-bar position-relative"> <div id="ad_rightslot" class="pub-container text-center"> <div 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</main> <div id="bandeau-footer"> <div class="container"> <p><a href="/abonnement" title="Abonnez-vous à Universalis pour 1 euro">Accédez à l'intégralité d'Universalis.fr <strong>sans publicité</strong></a></p> </div> </div> <footer class="container footer text-center d-print-none"> <ul class="list-inline list-inline-bullet mb-2"> <li class="list-inline-item"> <a href="http://www.encyclopaedia-universalis.fr/" title="Encyclopædia Universalis" rel="noopener" target="_blank">Encyclopædia Universalis </a> </li> <li class="list-inline-item"> <a href="https://www.encyclopaedia-universalis.fr/nous-contacter/infos/" title="Contactez-nous" rel="noopener nofollow" target="_blank">Contact</a></li> <li class="list-inline-item"> <a title="Mentions légales" rel="nofollow" href="/mentions-legales/">Mentions légales et politique de confidentialité</a> </li> <li class="list-inline-item"> <a title="Crédits images Accueil" rel="nofollow" href="/credits-illustrations/">Crédits images</a> </li> <li 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Tous droits de propriété industrielle et intellectuelle réservés.</p> </footer> <a href="javascript:" class="btn btn-primary" id="back-to-top" title="Retour en haut de page"><i aria-hidden="true" class="far fa-arrow-up"></i></a> <script> // noinspection ES6ConvertVarToLetConst,JSUnusedGlobalSymbols var subscription_uri = 'https://www.universalis.fr/abonnement/' bodyLoaded = true; loaded(); </script> <div class="modal" id="wd-help" tabindex="-1" style="display:none"> <div class="modal-dialog modal-xl"> <div class="modal-content"> <div class="modal-header"> <h5 class="modal-title">Aide</h5> <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button> </div> <div class="modal-body"> <p>L'outil Données Pays met à disposition un très grand nombre de données. Aussi, pour des raisons de performances et pour conserver une bonne expérience utilisateur, des règles de comparaison en nombre et en durée ont été mises en place :</p> <table class="table table-vcenter table-bordered table-sm"> <thead> <tr> <th>Pays</th> <th>Indicateurs</th> <th>Années</th> <th>Graphe</th> </tr> </thead> <tbody> <tr> <td>Jusqu'à 12 pays</td> <td>Toutes les données</td> <td>De 1960 à nos jours</td> <td> <ul class="list-unstyled m-0"> <li> <i class="fa fa-check text-success" aria-hidden="true"></i> <span class="visually-hidden">Affiché</span> en courbe </li> <li> <i class="fa fa-check text-success" aria-hidden="true"></i> <span class="visually-hidden">Affiché</span> en barre </li> </ul> </td> </tr> <tr> <td>De 13 à 50 pays</td> <td>5 données simultanées</td> <td>De 1960 à nos jours</td> <td> <ul class="list-unstyled m-0"> <li> <i class="fa fa-times text-danger" aria-hidden="true"></i> <span class="visually-hidden">Masqué</span> en courbe </li> <li> <i class="fa fa-check text-success" aria-hidden="true"></i> <span class="visually-hidden">Affiché</span> en barre </li> </ul> </td> </tr> <tr> <td>51 pays et plus</td> <td>1 seule donnée</td> <td>Sur une durée de 25 ans maximum</td> <td> <ul class="list-unstyled m-0"> <li> <i class="fa fa-times text-danger" aria-hidden="true"></i> <span class="visually-hidden">Masqué</span> en courbe </li> <li> <i class="fa fa-times text-danger" aria-hidden="true"></i> <span class="visually-hidden">Masqué</span> en barre </li> </ul> </td> </tr> </tbody> </table> <p>Lorsque la recherche porte sur <strong>une seule année</strong>, les résultats s’affichent sous forme de <strong>graphe en barre</strong>.</p> <p>Lorsque la recherche porte sur <strong>une période</strong>, les résultats s’affichent sous forme de <strong>graphe en courbe</strong>.</p> <p>Lorsque la recherche contient uniquement des données <strong>Informations générales</strong>, le champ <strong>Année ou période est désactivé</strong>, ces données ne possédant pas d'historique.</p> <p class="mb-0 text-sm text-muted text-end">v2.0</p> </div> </div> </div> </div> <script>(()=>{var e,a,r,_,c,d={},b={};function __webpack_require__(e){var a=b[e];if(void 0!==a)return a.exports;var r=b[e]={id:e,loaded:!1,exports:{}};return d[e].call(r.exports,r,r.exports,__webpack_require__),r.loaded=!0,r.exports}__webpack_require__.m=d,__webpack_require__.n=e=>{var a=e&&e.__esModule?()=>e.default:()=>e;return __webpack_require__.d(a,),a},__webpack_require__.d=(e,a)=>{for(var r in 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