Preprints
https://doi.org/10.5194/wcd-2021-39
https://doi.org/10.5194/wcd-2021-39

  21 Jun 2021

21 Jun 2021

Review status: this preprint is currently under review for the journal WCD.

How well is Rossby wave activity represented in the PRIMAVERA coupled simulations?

Paolo Ghinassi, Federico Fabiano, and Susanna Corti Paolo Ghinassi et al.
  • CNR-ISAC, Bologna, Italy

Abstract. This work aims to assess the performance of state of the art global climate models in representing the upper-tropospheric Rossby wave pattern in the Northern Hemisphere and over the Euro-Atlantic sector. A diagnostic based on Finite Amplitude Local Wave Activity is used as an objective metric to quantify the strength of Rossby waves in terms of Rossby wave activity. This diagnostic framework is applied to a set of coupled historical climate simulations at different horizontal resolutions, performed in the framework of the PRIMAVERA project and compared with observations (reanalysis). At first, the spatio-temporal characteristics of Rossby wave activity in the Northern Hemisphere are examined in the multimodel mean of the whole PRIMAVERA set. When examining the spatial distribution of transient wave activity no evident improvement is found in the high resolution ensemble. On the other hand, when examining the temporal variability of wave activity, an higher resolution is beneficial in all models apart from one. In addition, when examining the Rossby wave activity time series, no evident trends are found in the historical simulations (both at standard and high resolutions) and in the observations. Finally, the spatial distribution of Rossby wave activity is investigated in more detail focusing on the Euro-Atlantic sector, examining the wave activity pattern associated with Weather Regimes for each model. Results show a marked inter-model variability in representing the correct spatial distribution of Rossby wave activity associated with each regime pattern and an increased horizontal resolution improves the models performance only for some of the models and for some of the regimes. A positive impact of an increased horizontal resolution is found only for the models in which both the atmospheric and oceanic resolution is changed, whereas in the models in which only the atmospheric resolution is increased a worsening model performance is detected.

Paolo Ghinassi et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on wcd-2021-39', Anonymous Referee #1, 07 Jul 2021
  • RC2: 'Comment on wcd-2021-39', Anonymous Referee #2, 21 Jul 2021
  • AC1: 'Reply to reviewers', Paolo Ghinassi, 11 Oct 2021

Paolo Ghinassi et al.

Paolo Ghinassi et al.

Viewed

Total article views: 278 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
193 75 10 278 3 1
  • HTML: 193
  • PDF: 75
  • XML: 10
  • Total: 278
  • BibTeX: 3
  • EndNote: 1
Views and downloads (calculated since 21 Jun 2021)
Cumulative views and downloads (calculated since 21 Jun 2021)

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: 14 Oct 2021
Download
Short summary
In this work we examine the ability of global climate models in representing the atmospheric circulation in the upper troposphere, focusing on the eventual benefits of an increased horizontal resolution. Our results confirms that an higher horizontal resolution has a positive impact especially in those models in which the resolution is increased in both the atmosphere and the ocean, whereas when the resolution is increased only in the atmosphere no substantial improvements are found.