EGU24-2472, updated on 08 Mar 2024
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Comparison between non orographic gravity wave drag parameterizations used in QBOi models and Strateole2 constant level balloons                 

Raj Rani1, François Lott1, Charles McLandress4, Aurélien Podglagen1, Andrew Bushell5, Martina Bramberger9, Hyun-Kyu Lee6, M. Joan Alexander9, James Anstey4, Hye-Yeong Chun6, Albert Hertzog2, Bernard Legras1, Elisa Manzini8, Scott Osprey11, Riwal Plougonven3, John Scinocca4, Javier Serrano13, Federico Serva14, Tim Stockdale15, Stefan Versick16, and the Strateole 2 and QBOi contributors*
Raj Rani et al.
  • 1Laboratoire de Meteorologie Dynamique (LMD)/IPSL, PSL Research Institute, Ecole Normale Supérieure, Paris, France
  • 2LMD/IPSL, Sorbonne Université, Paris, France.
  • 3LMD/IPSL, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
  • 4Canadian Centre for Climate Modelling and Analysis (CCCma), Victoria, Canada
  • 5Met Office, FitzRoy Road, Exeter, UK
  • 6Yonsei University, Seoul, South Korea
  • 8Max Planck Institute for Meteorology, Hamburg, Germany
  • 9NorthWest Research Associates, Boulder Office, Boulder, CO, USA
  • 11Atmospheric, Oceanic and Planetary Physics, University of Oxford, Oxford, UK
  • 13Group of Meteorology Universitat de Barcelona, Barcelona, Spain
  • 14Institute of Marine Sciences, National Research Council, Rome, Italy
  • 15European Centre for Medium-Range Weather Forecasts (ECMWF), Reading, UK
  • 16Karlsruher Institut für Technologie (KIT), Karlsruhe, Germany
  • *A full list of authors appears at the end of the abstract

Gravity Waves (GWs) parameterizations from 14 General Circulation Models (GCMs) participating to the Quasi-Biennial Oscillation initiative (QBOi) are directly compared to Strateole-2 balloon observations made in the lower tropical stratosphere from November 2019 to February 2020 (phase 1) and from October 2021 and January 2022 (phase 2). The parameterizations span the 3 leading edge techniques used in GCMs to represent subgrid scale non-orographic GWs, the two globally spectral techniques developed by Hines (1997) and Warner and McIntyre (1999) respectively and the "multiwaves" approaches following Lindzen (1981). The input meteorological fields necessary to run the parameterizations offline are extracted from the ERA5 reanalysis and correspond to the instantaneous meteorological conditions found underneath the balloons.  In general, the amplitudes are in fair agreement between measurements of the momentum fluxes due to waves with periods less than 1 hr and the parameterizations. The correlation of the daily values between the observations and the results of the parameterization can be around 0.4, which is statistically significant elevated considering that we analyse around 1200 days of data and quite good considering that the parameterizations have not been tuned: the schemes used are just the standard ones that help producing a Quasi-Biennial Oscillation (QBO) in the corresponding model. These correlations nevertheless vary considerably between schemes and depend little on their formulation (globally spectral versus multiwaves for instance). We therefore attribute this agreement to dynamical filtering, which all schemes take good care of, whereas only a few relate gravity waves to their sources. Except for one parameterization, significant correlations are mostly found for eastward propagating waves, which may be due to the fact that during both Strateole 2 phases the QBO phase is easterly at the altitude of the balloon flights. On the other hand, statistical properties, like pdf of momentum fluxes seem better represented in spectral schemes with constant sources than in schemes ("spectral" or "multiwaves") that relate GWs to their convective sources.

Strateole 2 and QBOi contributors:

Young-Ha Kim, Institut für Atmosphäre und Umwelt, Goethe-Universität, Frankfurt am Main, Germany ( ) Hiroaki. Naoe, Meteorological Research Institute (MRI), Tsukuba, Japan ( Holger Pohlmann, Max Planck Institute for Meteorology, Hamburg, Germany ( Jadwiga H. Richter, National Center for Atmospheric Research (NCAR), Boulder, Colorado, USA ( Shingo Watanabe, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokohama, Japan ( Kohei Yoshida, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokohama, Japan (

How to cite: Rani, R., Lott, F., McLandress, C., Podglagen, A., Bushell, A., Bramberger, M., Lee, H.-K., Alexander, M. J., Anstey, J., Chun, H.-Y., Hertzog, A., Legras, B., Manzini, E., Osprey, S., Plougonven, R., Scinocca, J., Serrano, J., Serva, F., Stockdale, T., and Versick, S. and the Strateole 2 and QBOi contributors: Comparison between non orographic gravity wave drag parameterizations used in QBOi models and Strateole2 constant level balloons                 , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2472,, 2024.