2026-04-21 JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 2026 131(卷), 8(期), (null页)
An unprecedented extreme precipitation event struck the hyper-arid United Arab Emirates (UAE) and surrounding regions in mid-April 2024, severely disrupting infrastructure and public life. However, few studies pay attention to desert rainstorms. This study identifies Rossby wave breaking as the key dynamic mechanism underlying the extreme events. The pronounced positive sea surface temperature anomalies over the eastern North Atlantic-Mediterranean and land surface temperature anomalies over Eastern Europe acted as remote thermal forcings, triggering Rossby waves that propagated downstream and broke over the Arabian Peninsula, leading to enhanced upper-level divergence and dynamically induced ascent that contributed to the event. Specifically, the disruption of the Middle East jet at 200 hPa enhanced upper-tropospheric divergence, while strong convergence of southwest winds ahead of the Arabian vortex and southeast winds west of the subtropical high at 500 hPa promoted upward motion and moisture transport over the UAE. These findings emphasize the crucial role of remote ocean-atmosphere and land-atmosphere interactions in shaping extreme precipitation in arid regions and provide insights for improving forecasting and risk mitigation.
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