Moisture and wind effects of Rossby waves on Western Pacific Intertropical Convergence Zone breakdown events Casallas Garcia, Alejandro ; https://orcid.org/0000-0002-1988-5035 Mark Tompkins, Adrian Muller, Caroline J ; https://orcid.org/0000-0001-5836-5350 ddc:550 This study investigates the mechanisms driving clustered convection and the breakdown of the Intertropical Convergence Zone (ITCZ) over the Western Pacific Warm Pool using high‐resolution cloud‐resolving simulations and machine‐learning sensitivity experiments. Results show that ITCZ breakdown episodes, marked by spatially homogeneous convection and weakened meridional moisture gradients, are triggered primarily by anomalous moisture advection linked to the equatorial Rossby‐wave activity. While large‐scale moisture advection regulates the background convective state strongly, it is the surface and low‐level meridional winds that dominate transitions between clustered and random convection. Simulations demonstrate that moisture alone can sustain convective clustering, but breakdown episodes are more persistent and widespread when coupled with southerly meridional advection. These findings confirm that wave‐driven advection acts as a regulatory mechanism, periodically disrupting convective clustering and reshaping the meridional moisture gradient. This modulation of organization by wave‐induced breakdown events is critical for understanding tropical convection variability and its implications for the climate system. Wiley 2026 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/21217 Casallas Garcia A, Mark Tompkins A, Muller CJ. Moisture and wind effects of Rossby waves on Western Pacific Intertropical Convergence Zone breakdown events. <i>Quarterly Journal of the Royal Meteorological Society</i>. 2026. doi:<a href="https://doi.org/10.1002/qj.70131">10.1002/qj.70131</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1002/qj.70131 info:eu-repo/semantics/altIdentifier/issn/0035-9009 info:eu-repo/semantics/altIdentifier/e-issn/1477-870X https://creativecommons.org/licenses/by-nc/4.0/ info:eu-repo/semantics/openAccess