MLS Research

Dynamics, Transport, and Waves

Contact Gloria Manney

Dynamics and Transport are among the fundamental processes controlling the composition of the middle atmosphere (stratosphere and mesosphere) and its connections with the lower atmosphere (troposphere). Dynamics comprises the fundamental physical processes determining the characteristics and evolution of a fluid (the atmosphere) on rotating sphere externally forced by solar radiation. The study of atmospheric dynamics uses observations and mathematical models to characterize and explain the evolution of temperatures and winds, as well as products derived from them (e.g., geopotential heights, streamfunctions, vorticity and potential vorticity). An important aspect of this behavior is characterization of wave motions. Of particular importance in the middle atmoshpere are planetary scale (1 to 3 cycles around a latitude circle) waves that are forced by upper tropospheric weather systems or can be generated internally by instabilities in the background wind fields, and gravity waves.

In the stratosphere, the dominant feature of the circulation is the winter polar vortex, consisting of a band of strong winds westerly winds roughly encircling the pole (the polar night jet) that forms as a result of the fundamental balance between the Coriolis forcing and radiative forcing (air moves upward and poleward as a result of solar heating in the tropics, is deflected eastward by the Coriolis force, and descends in the polar winter because of very low temperatures there resulting from the absence of sunlight).

One of the most dramatic dynamical phenomena in the middle atmosphere is the midwinter stratospheric sudden warming (SSW). SSWs occur frequently (historically about once every two years on average) but unpredictably as a result of waves propagating from the upper troposphere under conditions that result in the waves breaking -- depositing their momentum -- in the upper stratosphere and leading to a breakdown of the winter stratospheric polar vortex. A similar process results in the "final warming" by which the polar vortex breaks down in spring, but SSWs are notable in that they disrupt and reverse the circulation in midwinter, leading to a period of easterly winds followed by a recovery to westerlies and re-establishment of the polar vortex. The most dramatic SSWs (three of which have occurred very recently, in Jan 2004, 2006, and 2009) (Manney et al, 2005, JGR; 2008, JGR, ACP; 2009, ACP, GRL) result in a complete disruption of the typical middle atmosphere high-latitude temperature structure (minimum near the tropopause, ~8-10km, maximum at the stratopause, ~50km), such that the conventional distinction between stratosphere and mesosphere is rendered somewhat meaningless (Manney et al 2008, JGR; 2009 GRL, and references therein). While SSWs are thought of as being controlled primarily by planetary scale wave motions, recent work has shown that gravity waves are also important, especially the re-establishment of the vortex after strong SSWs (e.g., Siskind et al, 2007).

The evolution of the circulation and wave motions in the middle atmosphere have also been shown to extend through the mesosphere (Lee et al, 2009, GRL, and references therein), and to affect the weather patterns in the upper troposphere, especially during extreme events such as SSWs. Dynamical processes and wave motions are also important in the tropics: Phenomena such as the annual cycle of upward transport of water vapor (and other trace gases, the so-called "tape-recorder" effect), the Quasi-biennial and semiannual oscillations, and Kelvin wave motions play a large role in determining the structure of the equatorial middle atmosphere.

The dynamics of the polar middle atmosphere is instrumental in determining the extent and timing of polar processing and ozone loss, since those processes are strongly dependent on temperature and vortex containment . In addition, dynamics play a large role in determining the composition of the middle atmosphere via transport processes. The relative roles of transport and chemistry in determining the distribution of trace gases depend on the time scales for chemical and dynamical changes; these time scales vary dramatically with season, altitude, latitude and species. Measurements of trace gases with long chemical lifetimes (e.g., N2O, in some regions CO, H2O, O3) provide information to quantify transport processes; this information is critical for assessing the ability of models to correctly reproduce atmospheric transporteg, (eg, Jin et al, 2009, ACP; Manney et al, 2009, ACP) and for calculations aimed at separating the contribution of chemical and dynamical processes to changes in atmospheric composition, especially for ozone (e.g., Manney et al, JAS, 1995a, b; Singleton et al, 2007, JGR; and references therein).

Prior to datasets from Aura MLS (and other instruments on that satellite), measurements of many species (including long-lived tracers) in the middle atmosphere were sporadic and limited in both spatial and temporal coverage. Aura MLS now provides measurements of long-lived tracers from the upper troposphere through the mesosphere with global daily coverage. CO, HNO3, O3, and H2O measurements are useful in the upper troposphere/lower stratosphere as in many situations they behave as tracers of transport there. N2O is a long-lived tracer useful in studying transport in the lower through the middle stratosphere. CO and H2O provide information on transport in the upper stratosphere and into the mesosphere. Measurements from Aura MLS and other recent satellite instruments have been and continue to be instrumental in improving our understanding of middle atmosphere dynamics and transport.

Further Reading


  • Labitzke and van Loon, "The Stratosphere" (Springer, 1999)


  • Andrews, Holton, and Leovy, "Middle Atmosphere Dynamics"

Review Papers

  • Shepherd, T.G., The Middle Atmosphere, JASTP, 2000
  • Shepherd, T.G., Transport in the middle atmosphere, JMSJ, 2007
  • Shepherd, T.G., Dynamics, Stratospheric Ozone, and Climate Change, Atmosphere-Ocean, 2008
  • Baldwin et al, The quasi-biennial oscillation, Rev. Geophys., 2001
  • Fritts and Alexander, Gravity Wave Dynamics and Effects in the Middle Atmosphere, Rev. Geophys., 2003

MLS-related publications concerning stratospheric dyanmics and transport

  1. Ruiz, D. and M. Prather
    From the middle stratosphere to the surface, using nitrous oxide to constrain the stratosphere-troposphere exchange of ozone
    Atmos. Chem. Phys. Discuss. doi:10.5194/acp-2021-635, in review
  2. Vogel, A., J. Ungermann and H. Elbern
    Analyzing trace gas filaments in the Ex-UTLS by 4D-variationalassimilation of airborne tomographic retrievals
    Atmos. Chem. Phys. Discuss. doi:10.5194/acp-2017-308, in review
  3. Roy, C., A.R. Ravishankara, P. Newman, L. David, S. Fadnavis, S. Rathod, L. Lait, R. Krishnan, H. Clark and B. Sauvage
    Estimation of Stratospheric Intrusions During Indian Cyclones
    Journal of Geophysical Research: Atmospheres doi:10.1029/2022jd037519, 2023
  4. Thurairajah, B., S. Bailey, V.L. Harvey, C. Randall and J. France
    The Role of the Quasi 5‐Day Wave on the Onset of Polar Mesospheric Cloud Seasons in the Northern Hemisphere
    Journal of Geophysical Research: Atmospheres doi:10.1029/2022jd037982, 2023
  5. Benito-Barca, S., N. Calvo and M. Abalos
    Driving mechanisms for the El Niño–Southern Oscillation impact on stratospheric ozone
    Atmos. Chem. Phys. 10.5194/acp-22-15729-2022, 2022
  6. Diallo, M., F. Ploeger, M. Hegglin, M. Ern, J. Grooß, S. Khaykin and M. Riese
    Stratospheric water vapour and ozone response to the quasi-biennial oscillation disruptions in 2016 and 2020
    Atmos. Chem. Phys. doi:10.5194/acp-22-14303-2022, 2022
  7. Eswaraiah, S., K. Seo, K. Kumar, M. Ratnam, A. Koval, J. Jeong, C. Mengist, Y. Lee, K. Greer, J. Hwang, W. Lee, M. Pramitha, G.V. Chalapathi, M.V. Reddy and Y. Kim
    Anthropogenic Influence on the Antarctic Mesospheric Cooling Observed during the Southern Hemisphere Minor Sudden Stratospheric Warming
    Atmosphere doi:10.3390/atmos13091475, 2022
  8. Fazel-Rastgar, F. and V. Sivakumar
    A severe weather system accompanied by a stratospheric intrusion during unusual warm winter in 2015 over the South Africa: An initial synoptic analysis
    Remote Sensing Applications: Society and Environment doi:10.1016/j.rsase.2022.100833, 2022
  9. Fujiwara, M., G.L. Manney, L.J. Gray and J.S. Wright
    SPARC Reanalysis Intercomparison Project S-RIP Final Report
    n/a 2022
  10. Gamelin, B., L. Carvalho and C. Jones
    Evaluating the influence of deep convection on tropopause thermodynamics and lower stratospheric water vapor: A RELAMPAGO case study using the WRF model
  11. Harvey, V.L., N. Pedatella, E. Becker and C. Randall
    Evaluation of Polar Winter Mesopause Wind in WACCMX+DART
    Journal of Geophysical Research: Atmospheres doi:10.1029/2022jd037063, 2022
  12. Lan, X., L. Zhu and Q. Yuan
    Long-Term Variation of Greenhouse Gas N2O Observed by MLS during 2005–2020
    Remote Sens. doi:10.3390/rs14040955, 2022
  13. Li, Y., S. Dhomse, M. Chipperfield, W. Feng, A. Chrysanthou, Y. Xia and D. Guo
    Effects of reanalysis forcing fields on ozone trends and age of air from a chemical transport model
    Atmos. Chem. Phys. doi:10.5194/acp-22-10635-2022, 2022
  14. Ma, Z., Y. Gong, S. Zhang, Q. Xiao, J. Xue, C. Huang and K. Huang
    Understanding the Excitation of Quasi‐6‐Day Waves in Both Hemispheres During the September 2019 Antarctic SSW
    Journal of Geophysical Research: Atmospheres doi:10.1029/2021jd035984, 2022
  15. Manney, G., L. Millán, M. Santee, K. Wargan, A. Lambert, J. Neu, F. Werner, Z. Lawrence, M. Schwartz, N. Livesey and W. Read
    Signatures of Anomalous Transport in the 2019/2020 Arctic Stratospheric Polar Vortex
    Journal of Geophysical Research: Atmospheres doi:10.1029/2022jd037407, 2022
  16. Martinsson, B., J. Friberg, O. Sandvik and M. Sporre
    Five-satellite-sensor study of the rapid decline of wildfire smoke in the stratosphere
    Atmos. Chem. Phys. 10.5194/acp-22-3967-2022, 2022
  17. Qie, K., W. Wang, W. Tian, R. Huang, M. Xu, T. Wang and Y. Peng
    Enhanced upward motion through the troposphere over the tropical western Pacific and its implications for the transport of trace gases from the troposphere to the stratosphere
    Atmos. Chem. Phys. doi:10.5194/acp-22-4393-2022, 2022
  18. Qin, Y., S. Gu, X. Dou, C. Teng and Z. Yang
    Secondary 12‐Day Planetary Wave in the Mesospheric Water Vapor During the 2016/2017 Unusual Canadian Stratospheric Warming
    Geophys. Res. Lett. doi:10.1029/2021gl097024, 2022
  19. Shams, S.B., V. Walden, J. Hannigan, W. Randel, I. Petropavlovskikh, A. Butler and A.D.l. Cámara
    Analyzing ozone variations and uncertainties at high latitudes during sudden stratospheric warming events using MERRA-2
    Atmos. Chem. Phys. doi:10.5194/acp-22-5435-2022, 2022
  20. Strahan, S., L. Coy, A. Douglass and M. Damon
    Faster Tropical Upper Stratospheric Upwelling Drives Changes in Ozone Chemistry
    Geophys. Res. Lett. doi:10.1029/2022gl101075, 2022
  21. Wohltmann, I., D. Kreyling and R. Lehmann
    Transport parameterization of the Polar SWIFT model version 2
    Geoscientific Model Development doi:10.5194/gmd-15-7243-2022, 2022
  22. Xiong, X., X. Liu, W. Wu, K.E. Knowland, Q. Yang, J. Welsh and D. Zhou
    Satellite observation of stratospheric intrusions and ozone transport using CrIS on SNPP
    Atmospheric Environment doi:10.1016/j.atmosenv.2022.118956, 2022
  23. Ziv, S.Z., C. Garfinkel, S. Davis and A. Banerjee
    The roles of the Quasi-Biennial Oscillation and El Niño for entry stratospheric water vapor in observations and coupled chemistry–ocean CCMI and CMIP6 models
    Atmos. Chem. Phys. doi:10.5194/acp-22-7523-2022, 2022
  24. Ern, M., M. Diallo, P. Preusse, M. Mlynczak, M. Schwartz, Q. Wu and M. Riese
    The semiannual oscillation SAO in the tropical middle atmosphere and its gravity wave driving in reanalyses and satellite observations
    Atmos. Chem. Phys. doi:10.5194/acp-21-13763-2021, 2021
  25. Feng, J. and Y. Huang
    Impacts of tropical cyclones on the thermodynamic conditions in the tropical tropopause layer observed by A-Train satellites
    Atmos. Chem. Phys. doi:10.5194/acp-21-15493-2021, 2021
  26. Gerding, M., G. Baumgarten, M. Zecha, F. Lübken, K. Baumgarten and R. Latteck
    On the unusually bright and frequent noctilucent clouds in summer 2019 above Northern Germany
    J. Atmos. Solar-Terr. Phys. doi:10.1016/j.jastp.2021.105577, 2021
  27. He, X., J. Luo, X. Xu, L. Ren, H. Tian, L. Shang and P. Xu
    The QBO Modulation on CO Distribution in the UTLS Over the Asian Monsoon Region During Boreal Summer
    Front. Earth Sci. doi:10.3389/feart.2021.625990, 2021
  28. Jenkins, G., V.D. Castro, B. Cunha, I. Fontanez and R. Holzworth
    The Evolution of the Wave‐One Ozone Maximum During the 2017 LASIC Field Campaign at Ascension Island
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd033972, 2021
  29. Karagodin-Doyennel, A., E. Rozanov, A. Kuchar, W. Ball, P. Arsenovic, E. Remsberg, P. Jöckel, M. Kunze, D. Plummer, A. Stenke, D. Marsh, D. Kinnison and T. Peter
    The response of mesospheric H2O and CO to solar irradiance variability in models and observations
    Atmos. Chem. Phys. doi:10.5194/acp-21-201-2021, 2021
  30. Liu, G., S. England, C. Lin, N. Pedatella, J. Klenzing, C. Englert, B. Harding, T. Immel and D. Rowland
    Evaluation of Atmospheric 3‐Day Waves as a Source of Day‐to‐Day Variation of the Ionospheric Longitudinal Structure
    Geophys. Res. Lett. doi:10.1029/2021gl094877, 2021
  31. Liu, M. and D. Hu
    Contrast relationships between Arctic Oscillation and ozone in the stratosphere over the Arctic in early and mid‐to‐late winter
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd033426, 2021
  32. McCormack, J., V.L. Harvey, C. Randall, N. Pedatella, D. Koshin, K. Sato, L. Coy, S. Watanabe, F. Sassi and L. Holt
    Intercomparison of middle atmospheric meteorological analyses for the Northern Hemisphere winter 2009–2010
    Atmos. Chem. Phys. 10.5194/acp-21-17577-2021, 2021
  33. Nishiyama, T., M. Taguchi, H. Suzuki, P. Dalin, Y. Ogawa, U. Brändström and T. Sakanoi
    Temporal evolutions of N2 Meinel (1,2) band near 1.5µm associated with aurora breakup and their effects on mesopause temperature estimations from OH Meinel (3,1) band
    Earth, Planets and Space 10.1186/s40623-021-01360-0, 2021
  34. Pumphrey, H., M. Schwartz, M. Santee, G. Kablick III, M. Fromm and N. Livesey
    Microwave Limb Sounder MLS observations of biomass burning products in the stratosphere from Canadian forest fires in August 2017
    Atmos. Chem. Phys. doi:10.5194/acp-21-16645-2021, 2021
  35. Qin, Y., S. Gu and X. Dou
    A New Mechanism for the Generation of Quasi‐6‐Day and Quasi‐10‐Day Waves During the 2019 Antarctic Sudden Stratospheric Warming
    Journal of Geophysical Research: Atmospheres doi:10.1029/2021jd035568, 2021
  36. Qin, Y., S. Gu, X. Dou, C. Teng and H. Li
    On the Westward Quasi‐8‐Day Planetary Waves in the Middle Atmosphere During Arctic Sudden Stratospheric Warmings
    Journal of Geophysical Research: Atmospheres doi:10.1029/2021jd035071, 2021
  37. Rieger, L.A., W.J. Randel, A.E. Bourassa and S. Solomon
    Stratospheric Temperature and Ozone Anomalies Associated With the 2020 Australian New Year Fires
    Geophys. Res. Lett. doi:10.1029/2021gl095898, 2021
  38. Siskind, D., V.L. Harvey, F. Sassi, J. McCormack, C. Randall, M. Hervig and S. Bailey
    Two- and three-dimensional structures of the descent of mesospheric trace constituents after the 2013 sudden stratospheric warming elevated stratopause event
    Atmos. Chem. Phys. doi:10.5194/acp-21-14059-2021, 2021
  39. Sukhodolov, T., T. Egorova, A. Stenke, W. Ball, C. Brodowsky, G. Chiodo, A. Feinberg, M. Friedel, A. Karagodin-Doyennel, T. Peter, J. Sedlacek, S. Vattioni and E. Rozanov
    Atmosphere–ocean–aerosol–chemistry–climate model SOCOLv4.0: description and evaluation
    Geoscientific Model Development doi:10.5194/gmd-14-5525-2021, 2021
  40. von Gathen, P.D., R. Kivi, I. Wohltmann, R. Salawitch and M. Rex
    Climate change favours large seasonal loss of Arctic ozone
    Nature Communications doi:10.1038/s41467-021-24089-6, 2021
  41. Das, S. and K.V. Suneeth
    Seasonal and interannual variations of water vapor in the upper troposphere and lower stratosphere over the Asian Summer Monsoon region- in perspective of the tropopause and ocean-atmosphere interactions
    J. Atmos. Solar-Terr. Phys. doi:10.1016/j.jastp.2020.105244, 2020
  42. Eswaraiah, S., K.N. Kumar, Y.H. Kim, G.V. Chalapathi, W. Lee, G. Jiang, C. Yan, G. Yang, M.V. Ratnam, P.V. Prasanth, S.V.B. Rao and K. Thyagarajan
    Low-latitude mesospheric signatures observed during the 2017 sudden stratospheric warming using the fuke meteor radar and ERA-5
    J. Atmos. Solar-Terr. Phys. 2020
  43. Fadnavis, S., C. Sioris, N. Wagh, R. Chattopadhyay, M. Tao, P. Chavan and T. Chakroborty
    A rising trend of double tropopauses over South Asia in a warming environment: Implications for moistening of the lower stratosphere
    International Journal of Climatology doi:10.1002/joc.6677, 2020
  44. García‐Comas, M., B. Funke, M. López‐Puertas, F. González‐Galindo, M. Kiefer and M. Höpfner
    First detection of a Brief Mesoscale Elevated Stratopause in very early winter
    Geophys. Res. Lett. doi:10.1029/2019GL086751, 2020
  45. Girach, I., P. Nair, N. Ojha and L. Sahu
    Tropospheric carbon monoxide over the northern Indian Ocean during winter: influence of inter-continental transport
    Climate Dynamics doi:10.1007/s00382-020-05269-4, 2020
  46. Gordon, E., A. Seppälä and J. Tamminen
    Evidence for energetic particle precipitation and quasi-biennial oscillation modulations of the Antarctic NO2 springtime stratospheric column from OMI observations
    Atmos. Chem. Phys. doi:10.5194/acp-20-6259-2020, 2020
  47. Han, Y., F. Xie and J. Zhang
    Has Stratospheric HCl in the Northern Hemisphere Been Increasing Since 2005?
    Front. Earth Sci. doi:10.3389/feart.2020.609411, 2020
  48. Honomichl, S. and L. Pan
    Transport From the Asian Summer Monsoon Anticyclone Over the Western Pacific
    Journal of Geophysical Research: Atmospheres doi:10.1029/2019jd032094, 2020
  49. Jensen, E.J., L. Pan, S. Honomichl, G. Diskin, M. Krämer, N. Spelten, G. Günther, D. Hurst, M. Fujiwara, H. Vömel, H. Selkirk, J. Suzuki, M. Schwartz and J. Smith
    Assessment of Observational Evidence for Direct Convective Hydration of the Lower Stratosphere
    Journal of Geophysical Research: Atmospheres doi:10.1029/2020jd032793, 2020
  50. Kablick, G.P., D.R. Allen, M.D. Fromm and G.E. Nedoluha
    Australian pyroCb smoke generates synoptic‐scale stratospheric anticyclones
    Geophys. Res. Lett. doi:10.1029/2020gl088101, 2020