Preprints
https://doi.org/10.5194/acp-2022-836
https://doi.org/10.5194/acp-2022-836
09 Jan 2023
 | 09 Jan 2023
Status: this preprint is currently under review for the journal ACP.

Constraints on simulated past Arctic amplification and lapse-rate feedback from observations

Olivia Linke, Johannes Quaas, Finja Baumer, Sebastian Becker, Jan Chylik, Sandro Dahlke, André Ehrlich, Dörthe Handorf, Christoph Jacobi, Heike Kalesse-Los, Luca Lelli, Sina Mehrdad, Roel A. J. Neggers, Johannes Riebold, Pablo Saavedra Garfias, Niklas Schnierstein, Matthew D. Shupe, Chris Smith, Gunnar Spreen, Baptiste Verneuil, Kameswara S. Vinjamuri, Marco Vountas, and Manfred Wendisch

Abstract. The Arctic has warmed much more than the global mean during past decades. The lapse-rate feedback (LRF) has been identified as large contributor to the Arctic amplification (AA) of climate change. This particular feedback arises from the vertically non-uniform warming of the troposphere, which in the Arctic emerges as strong near-surface, and muted free-tropospheric warming. Stable stratification and meridional energy transport are two characteristic processes that are evoked as causes for this vertical warming structure. Our aim is to constrain these governing processes by making use of detailed observations in combination with the large climate model ensemble of the 6th Coupled Model Intercomparison Project (CMIP6). We build on the result that CMIP6 models show a large scatter in Arctic LRF and AA, which are positively correlated for the historical period 1951–2014. Thereby, we present process-oriented constraints by linking characteristics of the current climate to historical climate simulations. In particular, we compare a large consortium of present-day observations to co-located model data from subsets with weak and strong simulated AA and Arctic LRF in the past. Our results firstly suggest that local Arctic processes mediating the lower thermodynamic structure of the atmosphere are more realistically depicted in climate models with weak Arctic LRF and AA (CMIP6/w) in the past. In particular, CMIP6/w models show stronger inversions at the end of the simulation period (2014) for boreal fall and winter, which is more consistent with the observations. This result is based on radiosonde observations from the year-long MOSAiC expedition in the central Arctic, together with long-term radio soundings at the Utqiaǵvik site in Alaska, USA, and dropsonde measurements from aircraft campaigns in the Fram Strait. Secondly, remote influences that can further mediate the warming structure in the free troposphere are more realistically represented by models with strong simulated Arctic LRF and AA (CMIP6/s) in the past. In particular, CMIP6/s models systemically simulate a stronger Arctic energy transport convergence in the present climate for boreal fall and winter, which is more consistent with reanalysis results. Locally, we find links between changes in transport pathways and vertical warming structures that favor a positive LRF in the CMIP6/s simulations. This hints to the mediating influence of advection on the Arctic LRF. We emphasise that one major attempt of this work is to give insights in different perspectives on the Arctic LRF. We present a variety of contributions from a large collaborative research consortium to ultimately find synergy among them in support of advancing our understanding of the Arctic LRF.

Olivia Linke 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 acp-2022-836', Anonymous Referee #1, 26 Jan 2023
  • RC2: 'Comment on acp-2022-836', Anonymous Referee #2, 30 Jan 2023

Olivia Linke et al.

Olivia Linke et al.

Viewed

Total article views: 967 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
711 239 17 967 19 5
  • HTML: 711
  • PDF: 239
  • XML: 17
  • Total: 967
  • BibTeX: 19
  • EndNote: 5
Views and downloads (calculated since 09 Jan 2023)
Cumulative views and downloads (calculated since 09 Jan 2023)

Viewed (geographical distribution)

Total article views: 941 (including HTML, PDF, and XML) Thereof 941 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 15 May 2023
Download
Short summary
The lapse-rate feedback (LRF) is a major driver of the "Arctic amplification" of climate change. It arises since the warming is more pronounced at the surface than aloft. There are several processes mediating the LRF in the Arctic, for instance the omnipresent temperature inversion. Here, we compare multi-model climate simulations to Arctic-based observations from a large research consortium to broaden our understanding of these processes, find synergy among them, and constrain the Arctic LRF.
Altmetrics