Combined effects of ENSO and PDO on Activity of Major Hurricanes in Eastern North Pacific

Abstract

Major hurricanes (MHs) in the eastern North Pacific (ENP) in 1970-2018 were clustered into 3 categories with different quantity, intensity, lifetime, translation speed, track and large-scale environmental fields. MHs in all three clusters are more active in the Pacific Decadal Oscillation (PDO) warm phase than cold phase period. There are two clusters that their relationship with El Niño Southern Oscillation (ENSO) were modulated by PDO. The first cluster generates and develops in the open ocean and has an increasing trend of annual frequency, which is more active during El Niño years than during La Niña years in the PDO cold phase, but equally active in the PDO warm phase. The second cluster generates in the nearshore and translate rapidly into the ocean, which is more active during La Niña years than during El Niño years in the PDO warm phase, but equally active in the PDO cold phase. The PDO modulation mainly result from that MHs are obviously active during La Niña years in the PDO warm phase, which can be explained by local warming sea surface temperature, lower vertical wind shear, increasing vorticity and weakening sinking branch of circulation like Hadley cell. Therefore, PDO modulation cannot be ignored when predict the activity of tropical cyclone in ENP, especially for MHs that enters the open ocean and threat the islands such as the Hawaiian Islands.

Characterization, variability and long‐term trends on local climate in a Mexican tropical dry forest

“…PDO, in particular, has been found to have an influence on the periodicity of TCs activity (Pazos & Mendoza, 2013) and landfalling events (Raga et al, 2013). Importantly, we found a positive correlation between MEI and PDO (Spearman's rho 0.678; p < 0.05) and other authors reported that a warm phase of PDO can strengthen an El Niño event (Huang et al, 2021; Wang & Liu, 2016). Moreover, interbasin teleconnections with the North Atlantic also modulates TC activity in the NEP.…”