Preprints
https://doi.org/10.5194/egusphere-2024-735
https://doi.org/10.5194/egusphere-2024-735
14 Mar 2024
 | 14 Mar 2024
Status: this preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).

Influence of mid-latitude Sea Surface Temperature Fronts on the Atmospheric Water Cycle and Storm Track Activity

Fumiaki Ogawa and Thomas Spengler

Abstract. The climatological mean turbulent air-sea heat exchange maximises along midlatitude sea surface temperature (SST) fronts that anchor midlatitude storm tracks. This implies a crucial role of the air-sea latent heat exchange along the SST fronts on the atmospheric water cycle and storm tracks through the intensification of atmospheric cyclones and their associated precipitation. We investigate the sensitivity of the atmospheric water cycle to the SST front through a set of aqua-planet experiments. Varying the latitude of a zonally symmetric midlatitude SST front, the midlatitude atmospheric water cycle responds through distinct changes in surface latent heat fluxes, precipitation, as well as atmospheric moisture fluxes, whereas the tropical latitudes remain largely unchanged. As storm tracks are self-maintained through the diabatic generation of eddy available potential energy, the position of the storm track is diabatically anchored at the SST front. While the position of the SST front determines the position of the eddy moisture convergence and thus the diabatic heating that energises the storm track, the underlying SST determines the general strength of the water cycle and thus the intensity of the storm track. The strong connection identified between the eddy moisture flux and the SST front implies a diabatic pathway of latent heating to anchor the storm track along SST fronts.

Fumiaki Ogawa and Thomas Spengler

Status: open (until 28 Apr 2024)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Fumiaki Ogawa and Thomas Spengler
Fumiaki Ogawa and Thomas Spengler

Viewed

Total article views: 111 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
80 27 4 111 11 4 4
  • HTML: 80
  • PDF: 27
  • XML: 4
  • Total: 111
  • Supplement: 11
  • BibTeX: 4
  • EndNote: 4
Views and downloads (calculated since 14 Mar 2024)
Cumulative views and downloads (calculated since 14 Mar 2024)

Viewed (geographical distribution)

Total article views: 150 (including HTML, PDF, and XML) Thereof 150 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 13 Apr 2024
Download
Short summary
The exchange of energy and moisture between the atmosphere and ocean maximises along strong meridional contrasts in sea surface temperature, such as across the Gulf Stream and Kuroshio. We find that these strong meridional contrasts confine and determine the position of evaporation and precipitation, as well as the storm occurrence and intensity. The general intensity of the water cycle and storm activity, however, are determined by the underlying absolute sea surface temperature.