Preprints
https://doi.org/10.5194/egusphere-2025-3639
https://doi.org/10.5194/egusphere-2025-3639
11 Aug 2025
 | 11 Aug 2025
Status: this preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).

Trade wind regimes during the Great Barrier Reef coral bleaching season

Lara S. Richards, Steven T. Siems, Yi Huang, Daniel P. Harrison, and Wenhui Zhao

Abstract. The trade winds over the Great Barrier Reef (GBR) dominate the local weather in the region, bringing cooler and drier air over the Reef, which promotes ocean cooling. The absence of the trade winds is often marked by periods of weaker winds and higher humidity, known as the doldrums, which cause ocean temperatures to spike and can develop into marine heatwaves that lead to coral bleaching. As the shallow waters of the GBR are strongly tied to the local meteorology, studying the evolution and structure of the trade winds during the austral warmer months is essential for understanding the development of thermal bleaching events. Through a K-Means cluster analysis on reanalysis soundings from Davies Reef from December–April 1996–2024, we find the formation of the doldrums is linked to the passage of a Rossby-wave train over eastern Australia. Years with mass thermal bleaching are correlated with more doldrums days, but also less of the strong trade wind days in December and April which can promote early-summer warming and allow warmer temperatures to persist later into the season.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this paper. While Copernicus Publications makes every effort to include appropriate place names, the final responsibility lies with the authors. Views expressed in the text are those of the authors and do not necessarily reflect the views of the publisher.
Share
Lara S. Richards, Steven T. Siems, Yi Huang, Daniel P. Harrison, and Wenhui Zhao

Status: open (until 05 Oct 2025)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Lara S. Richards, Steven T. Siems, Yi Huang, Daniel P. Harrison, and Wenhui Zhao
Lara S. Richards, Steven T. Siems, Yi Huang, Daniel P. Harrison, and Wenhui Zhao

Viewed

Total article views: 314 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
280 29 5 314 30 27
  • HTML: 280
  • PDF: 29
  • XML: 5
  • Total: 314
  • BibTeX: 30
  • EndNote: 27
Views and downloads (calculated since 11 Aug 2025)
Cumulative views and downloads (calculated since 11 Aug 2025)

Viewed (geographical distribution)

Total article views: 309 (including HTML, PDF, and XML) Thereof 309 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 05 Sep 2025
Download
Short summary
By studying the variability of the trade winds (persistent south-easterlies) during the Great Barrier Reef coral bleaching season, we show that ocean heating and a higher risk of coral bleaching are linked to the breakdown of the trade winds into either calm and clear conditions or a monsoon-like northerly flow. Years with mass coral bleaching are also associated with more "calm and clear" days in the warmest months and fewer strong trade wind days on the fringe months of the bleaching season.
Share