Preprints
https://doi.org/10.5194/acp-2022-389
https://doi.org/10.5194/acp-2022-389
 
01 Jul 2022
01 Jul 2022
Status: this preprint is currently under review for the journal ACP.

Intermittency of gravity wave potential energies and absolute momentum fluxes derived from infrared limb sounding satellite observations

Manfred Ern, Peter Preusse, and Martin Riese Manfred Ern et al.
  • Institut für Energie- und Klimaforschung – Stratosphäre (IEK–7), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany

Abstract. Atmospheric gravity waves contribute significantly to the driving of the global atmospheric circulation. Because of their small spatial scales, their effect on the circulation is usually parameterized in general circulation models. These parameterizations, however, are strongly simplified. One important effect that is often neglected is the fact that gravity wave sources, and thus the global distribution of gravity waves, are both very intermittent. Therefore, time series of global observations of gravity waves are needed to study the distribution, seasonal variation, and strength of this effect.

For gravity wave absolute momentum fluxes and potential energies observed by the limb sounding satellite instruments High Resolution Dynamics Limb Sounder (HIRDLS) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), we investigate the global distribution of gravity wave intermittency by deriving probability density functions (PDFs) in different regions, as well as global distributions of Gini coefficients. In the stratosphere, we find that intermittency is strongest in mountain wave regions, followed by the polar night jets, and regions of deep convection in the summertime subtropics. Intermittency is weakest in the tropics. A better comparability of intermittency in different years and regions is achieved by normalizing single observations by their monthly median distributions. Our results are qualitatively in agreement with previous findings from satellite observations, and quantitatively in good agreement with previous findings from superpressure balloons and high resolution models. Generally, momentum fluxes exhibit stronger intermittency than potential energies, and lognormal distributions are often a reasonable approximation of the PDFs. In the tropics, we find that, for monthly averages, intermittency increases with altitude, which might be a consequence of variations in the atmospheric background, and thus varying gravity wave propagation conditions. Different from this, in regions of stronger intermittency, particularly in mountain wave regions, we find that intermittency decreases with altitude, which is likely related to the dissipation of large-amplitude gravity waves during their upward propagation.

Manfred Ern et al.

Status: open (until 07 Sep 2022)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • CC1: 'Comment on acp-2022-389', Petr Šácha, 27 Jul 2022 reply

Manfred Ern et al.

Manfred Ern et al.

Viewed

Total article views: 278 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
204 66 8 278 2 3
  • HTML: 204
  • PDF: 66
  • XML: 8
  • Total: 278
  • BibTeX: 2
  • EndNote: 3
Views and downloads (calculated since 01 Jul 2022)
Cumulative views and downloads (calculated since 01 Jul 2022)

Viewed (geographical distribution)

Total article views: 283 (including HTML, PDF, and XML) Thereof 283 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 08 Aug 2022
Download
Short summary
Based on data of the two infrared limb sounding satellite instruments HIRDLS and SABER we investigate the intermittency of global distributions of gravity wave (GW) potential energies and GW momentum fluxes in the stratosphere and mesosphere using probability distribution functions (PDFs) and Gini coefficients. We compare GW intermittency in different regions, seasons, and altitudes. These results can help to improve GW parameterizations and distributions of GWs resolved in models.
Altmetrics