{"id":27,"date":"2004-11-28T11:09:50","date_gmt":"2004-11-28T15:09:50","guid":{"rendered":"\/?p=27"},"modified":"2005-03-31T16:14:53","modified_gmt":"2005-03-31T20:14:53","slug":"general-circulation-model-gcm","status":"publish","type":"post","link":"https:\/\/www.realclimate.org\/index.php\/archives\/2004\/11\/general-circulation-model-gcm\/","title":{"rendered":"General Circulation Model (“GCM”) Modele de Circulation G\u00e9n\u00e9rale (MCG – “GCM”)<\/lang_fr>"},"content":{"rendered":"
\n

Typically refers to a three-dimensional model of the global atmosphere used in climate modeling (often erroneously called “Global Climate Model”). This term often requires additional qualification (e.g., as to whether or not the atmosphere is fully coupled to an ocean–see ‘Atmosphere-Ocean General Circulation Model’<\/a>). <\/p>\n

The length scales that are resolved in these models is typically on the order of 100s of kilometers (i.e. features that size or smaller are not directly resolved). The timestep for the models (how often the fields are updated) is usually 20 minutes to an hour. Thus in any day there would be 24 to 72 loops of the main calculations. <\/p>\n

The basic variables are the temperature, humidity, liquid\/ice water content and atmospheric mass. The physics usually consists of advection, radiation calculations, surface fluxes (latent, sensible heat etc.), convection, turbulence and clouds. More elaborate Earth System models often contain tracers related to atmospheric chemistry and aerosols (including dust and sea salt).<\/p>\n

Modele tri-dimensionnel global de l’atmosphere utilis\u00e9 en mod\u00e9lisation climatique (souvent faussement nomm\u00e9 “Modele Climatique Global”). Ce terme g\u00e9n\u00e9rique est souvent pr\u00e9cis\u00e9 par des informations compl\u00e9mentaires (comme par exemple quand ce modele est coupl\u00e9 a l’ocean – voir “Modele de Circulation G\u00e9n\u00e9rale Oc\u00e9an-Atmosphere<\/a>”<\/p>\n

Les \u00e9chelles de distances r\u00e9solues dans ces modeles sont typiquement de l’ordre de la centaine de kilometres (c.a.d. que les caracteristiques de cette taille ou plus petites ne sont pas directement resolues). La r\u00e9solution temporelle de ces modeles (fr\u00e9quence de calcul des diff\u00e9rents champs) est comprise en g\u00e9n\u00e9ral entre 20 minutes et une heure. Ainsi, pour une journ\u00e9e, les calculs principaux seront effectu\u00e9s entre 24 et 72 fois.<\/p>\n

Les variables fondamentales d’un modele sont le temperature, l’humidit\u00e9, la fraction liquide\/glace de l’eau et la masse atnosph\u00e9rique. La physique du modele prend en compte l’advection, les calculs de radiations, les flux de surface (chaleur latente, sensible, etc…), la convection, turbulence, et les nuages. Les modeles les plus elabor\u00e9s du Systeme Terre contiennent souvent des marqueurs li\u00e9s a la chimie atmospherique et aux aerosols (incluant les poussieres et le sel de mer).
\n<\/lang_fr><\/p>\n\n<\/div> ","protected":false},"excerpt":{"rendered":"

Typically refers to a three-dimensional model of the global atmosphere used in climate modeling (often erroneously called “Global Climate Model”). This term often requires additional qualification (e.g., as to whether or not the atmosphere is fully coupled to an ocean–see ‘Atmosphere-Ocean General Circulation Model’). The length scales that are resolved in these models is typically […]<\/p>\n","protected":false},"author":12,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[6],"tags":[],"class_list":{"0":"post-27","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-glossary","7":"entry"},"aioseo_notices":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts\/27","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/comments?post=27"}],"version-history":[{"count":0,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/posts\/27\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/media?parent=27"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/categories?post=27"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.realclimate.org\/index.php\/wp-json\/wp\/v2\/tags?post=27"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}