Preprints
https://doi.org/10.5194/egusphere-2022-1261
https://doi.org/10.5194/egusphere-2022-1261
 
23 Dec 2022
23 Dec 2022
Status: this preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).

Divergent convective outflow in large eddy simulations

Edward Groot and Holger Tost Edward Groot and Holger Tost
  • Institut für Physik der Atmosphäre, Johannes Gutenberg Universität, Johannes-Joachim-Becher-Weg 21, Mainz, Germany

Abstract. Upper tropospheric outflow is analysed in cloud resolving large eddy simulations. Thereby, the role of convective organisation, latent heating and other factors in upper tropospheric divergent outflow variability from deep convection is diagnosed using a set of about 100 large eddy simulations, because the outflows are thought to be an important feedback from (organised) to large scale atmospheric flows: perturbations in those outflows may sometimes propagate into larger scale perturbations.

Upper tropospheric divergence is found to be controlled by net latent heating and convective organisation. At low precipitation rates isolated convective cells have a stronger mass divergence than squall lines. The squall line divergence is the weakest (relative to the net latent heating) when the outflow is purely 2D, in case of an infinite length squall line. At high precipitation rates the mass divergence discrepancy between the various modes of convection reduces. Hence, overall the magnitude of divergent outflow is explained by the latent heating and the dimensionality of the outflow, which together create a non-linear relation.

Edward Groot and Holger Tost

Status: open (until 16 Feb 2023)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Edward Groot and Holger Tost

Edward Groot and Holger Tost

Viewed

Total article views: 270 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
211 50 9 270 22 6 4
  • HTML: 211
  • PDF: 50
  • XML: 9
  • Total: 270
  • Supplement: 22
  • BibTeX: 6
  • EndNote: 4
Views and downloads (calculated since 23 Dec 2022)
Cumulative views and downloads (calculated since 23 Dec 2022)

Viewed (geographical distribution)

Total article views: 266 (including HTML, PDF, and XML) Thereof 266 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 04 Feb 2023
Download
Short summary
It is shown that the outflow from cumulonimbus clouds or thunderstorms in the upper troposphere/lower stratosphere in idealised high resolution simulations (LES) depends linearly on the net amount of latent heat released by the cloud for fixed geometrical structure of the cloud. However, it is shown that in more realistic situations, convective organisation and aggregation (collecting mechanisms of cumulonimbus clouds) affect the amount of outflow non-linearly through non-idealised geometry.