Pacific Decadal Oscillation Modulates the Relationship Between Pacific Meridional Mode and Tropical Cyclone Genesis in the Western North Pacific

Abstract

Tropical cyclones (TCs) over the western North Pacific (WNP) bring about enormous disasters to the Pacific islands and coastal regions (Peduzzi et al., 2012;Qin et al., 2023;Q. Zhang et al., 2009). Understanding variations in TC genesis, which largely determine the subsequent track, impact regions and the associated damages, would greatly benefit seasonal forecasting and thus the disaster mitigation for these regions (Camargo, Barnston, et al., 2007;Klotzbach et al., 2019).Sea surface temperature (SST) anomalies across the tropical and subtropical oceans including the Pacific Ocean, Atlantic Ocean and Indian Ocean, were found to play important roles in variations of the WNP TC genesis (Cai

Asymmetric Efficacies Between Warm and Cold Pacific Meridional Modes in Inducing ENSO

“…This observation aligns with previous research by Fan et al. (2023a, 2023b), which identified a negative skewness between ENSO‐induced cold and warm phases of PMM events.…”

“…This study primarily used the commonly employed PMM SST index as the PMM index. Additionally, we incorporate the PMM Wind index and another newly proposed PMM area‐averaged index (SSTAs over 115°–155°W, 10°–30°N) (Fan et al., 2023a, 2023b; Richter et al., 2022) for result verification. A warm (cold) PMM event is identified when the PMM index during the boreal spring (March‐April‐May, MAM) is greater (less) than or equal to 0.5 (−0.5) standard deviation.…”

Corals Reveal Interdecadal Variation of Tropical Cyclones Modulated by Pacific Decadal Oscillation

“…(2019) defined a western boundary index (WBI) to quantify east‐westward movement of WPSH. Both WBI and WPSH Western Ridge Point Index show the retreat of the WPSH to the east during the negative phase of the PDO (Figure 8e), which causes more favorable conditions (e.g., reduced vertical wind shear, enhanced moisture supply, and stronger upper‐level divergence) for TC formation in the SCS (Goh & Chan, 2010; Li & Zhou, 2014; Wang et al., 2023). In terms of the TC track, more TCs from the WNP entered the SCS in the negative phase of PDO, which could potentially be entrained by anomalous easterlies and directed toward the SCS (Goh & Chan, 2010).…”

“…Among them, the PDO was defined as the dominant empirical orthogonal function of SST anomalies north of 20°N in the Pacific (Mantua et al., 1997). SST anomalies during PDO phase shifts can induce atmospheric circulation anomalies, subsequently impacting TC activity (Goh & Chan, 2010; Wang et al., 2023). However, the implications of this phenomenon remain unidentified on the long‐term scale.…”

The Potential Influence of Maritime Continent Deforestation on El Niño‐Southern Oscillation: Insights From Idealized Modeling Experiments

“…The observed La Niña events are known to be mostly of the CP‐type than the EP‐type. The cause of this El Niño‐La Niña asymmetry is not yet fully understood, but one possible explanation is that the generation mechanism of La Niña may be more related to subtropical ENSO dynamics (e.g., Fan et al., 2023; Yu et al., 2023).…”