\select@language {french}
\contentsline {chapter}{\numberline {1}Introduction}{9}
\contentsline {section}{\numberline {1.1}Avant propos}{9}
\contentsline {section}{\numberline {1.2}Couplages entre composition et transport atmosph\'erique}{9}
\contentsline {section}{\numberline {1.3}Mod\'elisation du climat}{10}
\contentsline {section}{\numberline {1.4}Repr\'esentation du transport dans les mod\`eles globaux}{11}
\contentsline {section}{\numberline {1.5}Calculs de dispersion et surveillance de l'environnement}{12}
\contentsline {section}{\numberline {1.6}Couplages entre composition et dynamique sur Titan}{13}
\contentsline {chapter}{\numberline {2}Repr\'esentation du transport des esp\`eces traces}{17}
\contentsline {section}{\numberline {2.1}Le mod\`ele LMDZ}{19}
\contentsline {subsection}{\numberline {2.1.1}Description g\'en\'erale}{19}
\contentsline {subsection}{\numberline {2.1.2}Discr\'etisation des \'equations primitives}{20}
\contentsline {subsection}{\numberline {2.1.3}Les param\'etrisations physiques du mod\`ele de climat terrestre}{23}
\contentsline {subsection}{\numberline {2.1.4}Organisation informatique - version unidimensionnelle - mode guid\'e}{28}
\contentsline {section}{\numberline {2.2}L'\'equation de transport : s\'eparation d'\'echelles}{29}
\contentsline {subsection}{\numberline {2.2.1}S\'eparation des processus}{29}
\contentsline {subsection}{\numberline {2.2.2}S\'eparation d'\'echelles}{30}
\contentsline {section}{\numberline {2.3}Le transport grande \'echelle}{31}
\contentsline {subsection}{\numberline {2.3.1}Les diff\'erentes approches}{31}
\contentsline {subsection}{\numberline {2.3.2}Les sch\'emas en volumes finis}{32}
\contentsline {subsection}{\numberline {2.3.3}Description des sch\'emas en dimension un}{33}
\contentsline {subsection}{\numberline {2.3.4}Le sch\'ema de Godunov}{35}
\contentsline {subsection}{\numberline {2.3.5}Sch\'emas du second ordre}{36}
\contentsline {subsection}{\numberline {2.3.6}Limiteurs de pentes}{37}
\contentsline {subsection}{\numberline {2.3.7}Sch\'emas du troisi\`eme ordre}{39}
\contentsline {subsection}{\numberline {2.3.8}Introduction des sch\'emas dans LMDZ}{39}
\contentsline {subsection}{\numberline {2.3.9}Tests bidimensionnels}{43}
\contentsline {subsection}{\numberline {2.3.10}Remarques pour conclure}{47}
\contentsline {section}{\numberline {2.4}Le transport sous-maille}{47}
\contentsline {subsection}{\numberline {2.4.1}Turbulence de couche limite}{47}
\contentsline {subsection}{\numberline {2.4.2}Convection nuageuse}{48}
\contentsline {subsubsection}{Diffusion lat\'erale}{50}
\contentsline {section}{\numberline {2.5}Architecture}{50}
\contentsline {section}{\numberline {2.6}El\'ements de validation de la composante traceurs de LMDZ}{52}
\contentsline {subsection}{\numberline {2.6.1}Simulations Radon}{52}
\contentsline {subsection}{\numberline {2.6.2}Evaluation sur la campagne ETEX }{55}
\contentsline {subsection}{\numberline {2.6.3}Discussion}{56}
\contentsline {section}{\numberline {2.7}Applications et perspectives}{60}
\contentsline {subsection}{\numberline {2.7.1}Applications "traceurs" avec le mod\`ele LMDZ}{60}
\contentsline {subsubsection}{Etude des couplages chimie-climat et a\'erosols-climat sur Terre}{60}
\contentsline {subsubsection}{L'\'etude des grands cycles climatiques martiens}{61}
\contentsline {subsubsection}{Autres applications}{61}
\contentsline {subsection}{\numberline {2.7.2}Inclusion de la composante traceurs dans le mod\`ele de convection d'Emanuel}{61}
\contentsline {subsection}{\numberline {2.7.3}Transport des variables actives}{63}
\contentsline {subsubsection}{Advection verticale}{64}
\contentsline {subsubsection}{Vers les volumes finis}{65}
\contentsline {subsubsection}{Changement de grille}{66}
\contentsline {paragraph}{L'\'equation thermodynamique}{67}
\contentsline {chapter}{\numberline {3}Le ``mod\`ele du thermique" }{69}
\contentsline {section}{\numberline {3.1}Bases physiques des param\'etrisations en diffusion}{71}
\contentsline {subsection}{\numberline {3.1.1}La longueur de m\'elange}{71}
\contentsline {subsection}{\numberline {3.1.2}Les fermetures bas\'ees sur une \'equation pronostique de l'\'energie cin\'etique turbulente}{73}
\contentsline {subsection}{\numberline {3.1.3}Les fermetures bas\'ees sur un \'equilibre de l'\'energie cin\'etique turbulente}{78}
\contentsline {subsection}{\numberline {3.1.4}Les param\'etrisations bas\'ees sur des relations de similitude}{78}
\contentsline {section}{\numberline {3.2}Sp\'ecificit\'es de la couche limite convective}{81}
\contentsline {subsection}{\numberline {3.2.1}Organisation \`a meso-\'echelle}{82}
\contentsline {subsection}{\numberline {3.2.2}Le cycle diurne de la couche limite continentale}{87}
\contentsline {subsection}{\numberline {3.2.3}Caract\'erisation des grandeurs turbulentes dans la couche limite convective}{90}
\contentsline {subsection}{\numberline {3.2.4}Analyse d'\'echelle de la couche limite convective}{94}
\contentsline {section}{\numberline {3.3}Les fermetures non locales et la couche limite convective}{97}
\contentsline {subsection}{\numberline {3.3.1}Contre-gradient et mod\`eles non locaux}{97}
\contentsline {subsection}{\numberline {3.3.2}Matrices de transilience}{98}
\contentsline {subsection}{\numberline {3.3.3}Les mod\`eles en flux de masse}{99}
\contentsline {section}{\numberline {3.4}Le mod\`ele du thermique}{102}
\contentsline {subsection}{\numberline {3.4.1}Id\'ealisation d'une cellule thermique}{102}
\contentsline {subsection}{\numberline {3.4.2}D\'etra\IeC {\^\i }nement et environnement du thermique}{104}
\contentsline {subsection}{\numberline {3.4.3}Les \'equations du mod\`ele}{105}
\contentsline {subsection}{\numberline {3.4.4}Fermeture locale}{107}
\contentsline {section}{\numberline {3.5}Comparaison avec les simulations des grands tourbillons}{107}
\contentsline {subsection}{\numberline {3.5.1}Description des simulations des grands tourbillons}{108}
\contentsline {subsection}{\numberline {3.5.2}Les simulations uni-colonnes}{109}
\contentsline {subsection}{\numberline {3.5.3}R\'esultats num\'eriques}{110}
\contentsline {subsection}{\numberline {3.5.4}Sensibilit\'e aux param\`etres}{115}
\contentsline {subsection}{\numberline {3.5.5}Dans le thermique}{118}
\contentsline {subsection}{\numberline {3.5.6}Moments du second ordre}{118}
\contentsline {subsection}{\numberline {3.5.7}Transport de quantit\'e de mouvement}{121}
\contentsline {section}{\numberline {3.6}Simulations uni-colonnes de la POI~2 d'ESQUIF}{122}
\contentsline {subsection}{\numberline {3.6.1}La POI~2 d'ESQUIF}{122}
\contentsline {subsection}{\numberline {3.6.2}Les simulations unidimensionnelles}{123}
\contentsline {subsection}{\numberline {3.6.3}R\'esultats}{124}
\contentsline {section}{\numberline {3.7}Transport des traceurs dans la couche limite}{126}
\contentsline {section}{\numberline {3.8}Conclusions }{134}
\contentsline {subsection}{\numberline {3.8.1}R\'esum\'e des principaux r\'esultats}{134}
\contentsline {subsection}{\numberline {3.8.2}Les nuages}{135}
\contentsline {subsection}{\numberline {3.8.3}Utilisation du mod\`ele zoom\'e et guid\'e}{137}
\contentsline {chapter}{\numberline {4}Inversion du transport atmosph\'erique}{141}
\contentsline {section}{\numberline {4.1}Contexte}{141}
\contentsline {section}{\numberline {4.2}R\'etro-transport et transport adjoint}{145}
\contentsline {subsection}{\numberline {4.2.1}Sym\'etrie temporelle du transport atmosph\'erique}{146}
\contentsline {subsection}{\numberline {4.2.2}Extension \`a des sources et puits lin\'eaires}{147}
\contentsline {subsection}{\numberline {4.2.3}D\'erivation adjointe}{149}
\contentsline {subsection}{\numberline {4.2.4}Lien entre sym\'etrie et conservation}{151}
\contentsline {section}{\numberline {4.3}Sym\'etrie des param\'etrisations de la turbulence}{152}
\contentsline {subsection}{\numberline {4.3.1}S\'eparation d'\'echelle}{152}
\contentsline {subsection}{\numberline {4.3.2}Diffusion turbulente et \'emissions de surface}{152}
\contentsline {subsubsection}{Approche adjointe}{154}
\contentsline {subsection}{\numberline {4.3.3}Param\'etrisations en flux de masse du transport convectif}{155}
\contentsline {subsubsection}{Approche physique}{155}
\contentsline {subsubsection}{Convection adjointe}{156}
\contentsline {subsection}{\numberline {4.3.4}Matrices d'\'echange}{158}
\contentsline {section}{\numberline {4.4}Sym\'etrie des mod\`eles num\'eriques}{158}
\contentsline {subsection}{\numberline {4.4.1}Mise en {\oe }uvre dans LMDZ}{158}
\contentsline {subsection}{\numberline {4.4.2}Illustration num\'erique}{159}
\contentsline {subsection}{\numberline {4.4.3}Mod\`ele adjoint}{161}
\contentsline {subsection}{\numberline {4.4.4}V\'erification de la sym\'etrie temporelle des algorithmes}{162}
\contentsline {subsection}{\numberline {4.4.5}Sym\'etrie du sch\'ema d'advection}{163}
\contentsline {subsection}{\numberline {4.4.6}Diffusion turbulente}{165}
\contentsline {subsection}{\numberline {4.4.7}Mod\`eles de convection en flux de masse}{165}
\contentsline {subsection}{\numberline {4.4.8}Puits lin\'eaires}{167}
\contentsline {subsection}{\numberline {4.4.9}Sym\'etrie du mod\`ele complet}{167}
\contentsline {section}{\numberline {4.5}Le cas des algorithmes ne respectant pas la sym\'etrie}{167}
\contentsline {subsection}{\numberline {4.5.1}Calculs de sensibilit\'e}{167}
\contentsline {subsection}{\numberline {4.5.2}Exp\'eriences de minimisation}{171}
\contentsline {section}{\numberline {4.6}Illustrations et applications}{174}
\contentsline {subsection}{\numberline {4.6.1}Evaluation des capacit\'es de d\'etection du r\'eseau TICE}{174}
\contentsline {subsection}{\numberline {4.6.2}Inversion des param\`etres de la source}{177}
\contentsline {subsection}{\numberline {4.6.3}Inversion de sources continues}{178}
\contentsline {subsection}{\numberline {4.6.4}Quelques remarques d'ordre g\'en\'eral pour les applications}{178}
\contentsline {section}{\numberline {4.7}Conclusion}{179}
\contentsline {chapter}{\numberline {5}Dynamique et composition de la stratosph\`ere de Titan}{181}
\contentsline {section}{\numberline {5.1}Changement de d\'ecor}{181}
\contentsline {section}{\numberline {5.2}Mod\'elisation tridimensionnelle de la circulation}{185}
\contentsline {subsection}{\numberline {5.2.1}Mise en \'evidence de la superrotation}{185}
\contentsline {subsection}{\numberline {5.2.2}Mod\'elisation num\'erique}{188}
\contentsline {subsection}{\numberline {5.2.3}Le processus de Gierasch-Rossow}{189}
\contentsline {subsection}{\numberline {5.2.4}Superrotation : le cas de Titan}{192}
\contentsline {subsection}{\numberline {5.2.5}Mise en \'evidence des couplages entre dynamique et composition}{194}
\contentsline {section}{\numberline {5.3}Mod\'elisation coupl\'ee dynamique/microphysique/chimie}{199}
\contentsline {subsection}{\numberline {5.3.1}Le mod\`ele bidimensionnel}{199}
\contentsline {subsection}{\numberline {5.3.2}Transport latitudinal par les ondes dans un mod\`ele en eau peu profonde}{200}
\contentsline {subsection}{\numberline {5.3.3}Param\'etrisation en longueur de m\'elange du transport latitudinal des esp\`eces traces}{204}
\contentsline {subsection}{\numberline {5.3.4}Param\'etrisation du transport latitudinal du moment cin\'etique}{205}
\contentsline {subsection}{\numberline {5.3.5}Mod\'elisation de la brume}{207}
\contentsline {subsection}{\numberline {5.3.6}Mod\'elisation de la chimie}{208}
\contentsline {subsection}{\numberline {5.3.7}Grille et sp\'ecifications diverses}{209}
\contentsline {section}{\numberline {5.4}Couplages entre dynamique et composition}{210}
\contentsline {subsection}{\numberline {5.4.1}Origine de la brume d\'etach\'ee}{210}
\contentsline {subsection}{\numberline {5.4.2}R\'etroaction de la composition sur la dynamique}{213}
\contentsline {subsection}{\numberline {5.4.3}L'asym\'etrie Nord/Sud}{213}
\contentsline {section}{\numberline {5.5}Composition, vents et condensation}{216}
\contentsline {subsection}{\numberline {5.5.1}Composition du vortex polaire}{218}
\contentsline {subsection}{\numberline {5.5.2}Amplitude de l'enrichissement polaire}{222}
\contentsline {subsection}{\numberline {5.5.3}Contraintes sur les vents}{225}
\contentsline {subsection}{\numberline {5.5.4}Variations saisonni\`eres}{229}
\contentsline {subsection}{\numberline {5.5.5}Que va observer Cassini ?}{232}
\contentsline {section}{\numberline {5.6}Quelques remarques pour finir}{235}
\contentsline {chapter}{\numberline {6}Conclusions et perspectives}{239}
\contentsline {section}{\numberline {6.1}Quelques enseignements}{239}
\contentsline {subsection}{\numberline {6.1.1}D\'ecomposition et param\'etrisation du transport}{239}
\contentsline {subsection}{\numberline {6.1.2}Des traceurs du transport atmosph\'erique}{241}
\contentsline {section}{\numberline {6.2}Et apr\`es}{242}
\contentsline {subsection}{\numberline {6.2.1}Couplage couche limite, convection, nuages}{242}
\contentsline {subsection}{\numberline {6.2.2}Plan\`etes et climats}{246}
\contentsline {chapter}{\numberline {A}Lexique (jargon et acronymes)}{249}