Garny H. Causes and impacts of changes in the stratospheric meridional circulation in a chemistry-climate model: Diss. / Deutsches Zentrum für Luft- und Raumfahrt Institut für Physik der Atmosphäre, Oberpfaffenhofen - Köln: DLR, Bibliotheks- und Informationswesen, 2011. - vii, 139 p.: ill. - (Forschungsbericht; 2011-03). - Bibliogr.: p.129-138. - ISSN 1434-8454  Место хранения:   061 | Институт оптики атмосферы CO РАН | Томск | Библиотека

Оглавление / Contents

1 Introduction ................................................. 1 1.1 State of the art ........................................ 2 1.1.1 The Brewer-Dobson Circulation .................... 2 1.1.2 Stratospheric ozone .............................. 8 1.2 Thesis Objectives and Outline .......................... 11 2 Model description and simulation set-ups .................... 15 2.1 Model description of E39CA ............................. 15 2.2 Simulation set-ups ..................................... 16 2.2.1 Transient simulations ........................... 16 2.2.2 Sensitivity simulations ......................... 20 3 Diagnosing changes in the meridional circulation ............ 23 3.1 Background state ....................................... 23 3.2 Mean tropical upwelling ................................ 26 3.3 Residual circulation ................................... 29 3.4 Age of Air ............................................. 31 3.5 Width of the upwelling region .......................... 33 3.6 Summary ................................................ 35 4 Drivers of circulation changes .............................. 37 4.1 Impact of changes in GHGs, SSTs and CFCs ............... 37 4.1.1 Utilisation of the simulations to assign changes to the boundary conditions .............. 37 4.1.2 Background state ................................ 40 4.1.3 Residual Circulation ............................ 44 4.2 Impact of tropical versus extratropical SSTs ........... 45 4.3 Summary ................................................ 50 5 Wave forcing of the meridional circulation and tropical upwelling ................................................... 51 5.1 Wave forcing of tropical upwelling ................... 52 5.1.1 Downward control ................................ 52 5.1.2 EP fluxes ....................................... 58 5.2 Discussion ............................................. 65 5.2.1 Climatological forcing of tropical upwelling .... 66 5.2.2 Changes in wave generation ...................... 67 5.2.3 Changes in wave propagation ..................... 71 5.3 Summary ................................................ 73 6 Impact of changes in the stratospheric circulation on transport and ozone ......................................... 75 6.1 Evolution of atmospheric ozone ......................... 76 6.1.1 Trends in ozone ................................. 76 6.1.2 Drivers of ozone changes ........................ 77 6.2 Attribution of ozone changes to chemistry and transport .............................................. 80 6.2.1 Ozone origin diagnostic ......................... 81 6.2.2 Transport of ozone and air masses ............... 88 6.2.3 Attribution of long-term changes in ozone ....... 96 6.3 Discussion and summary ................................ 101 7 Conclusions and Outlook .................................... 105 7.1 Conclusions ........................................... 105 7.2 Outlook ............................................... 113 A Glossary and Abbreviations ................................. 117 B The ТЕМ equations and downward control ..................... 121 С Linear least square regression modelling ................... 125