Impacts of Tropical North Atlantic SST on Western North Pacific Landfalling Tropical Cyclones

Abstract

This study examines the impacts of tropical North Atlantic (TNA) sea surface temperature anomaly (SSTA) on western North Pacific (WNP) landfalling tropical cyclones (TCs). The authors find that TNA SSTA has significant negative correlations with the frequency of TCs making landfall in China, Vietnam, the Korean Peninsula and Japan, and the entirety of East Asia. TNA SSTA influences the frequency of TC landfalls in these regions by regulating TC genesis location and frequency associated with modulated environmental conditions. During cold TNA SST years, larger low-level relative vorticity and weaker vertical wind shear lead to more TC formations over the South China Sea (SCS) and western Philippine Sea (WPS), and larger low-level relative vorticity, higher midlevel relative humidity, and weaker vertical wind shear result in more TC formations over the eastern part of WNP (EWNP). More TCs forming over different regions are important for more TC landfalls in Vietnam (mainly forming over the SCS and WPS), south China (predominantly forming over the SCS), Taiwan (mostly forming over the WPS), and the Korean Peninsula and Japan (forming over the WPS and EWNP). Tracks of these landfalling TCs basically follow the mean steering flow in spite of different directions of steering flow anomalies in the vicinity. The modulation of large-scale environments by TNA SSTA may be through two possible pathways proposed in previous studies: the Indian Ocean relaying effect and the subtropical eastern Pacific relaying effect. The results of this study suggest that TNA SSTA is a potential predictor for the frequency of TCs making landfall in China, Vietnam, the Korean Peninsula and Japan, and the entirety of East Asia.

Western North Pacific Tropical Cyclone Activity in 2018: A Season of Extremes

“…On interannual time scales, the frequency of WNP TCs can be modulated by various climate factors such as the El Niño/La Niña Modoki 1,2 , the Pacific Meridional Mode (PMM) [3][4][5][6] , the Atlantic Meridional Mode 7 , tropical North Atlantic (TNA) sea surface temperature (SST) [8][9][10] , Indian Ocean SST [11][12][13][14] , and SST gradient between the southwestern Pacific Ocean and the western Pacific warm pool 15 . A more recent study has further pointed out that regional SST anomalies (SSTA) can modulate TC genesis in different parts of the WNP 16 .…”

Snow Level Characteristics and Impacts of a Spring Typhoon-Originating Atmospheric River in the Sierra Nevada, USA

“…As such conditions were present during the 5-7 April event, it opens the question of whether typhoon-induced ARs may be skillfully forecast at longer-lead times. Typhoon frequency can be predicted using climate modes such as the Pacific Meridional Mode [39] and states such as Indian Ocean and Atlantic sea surface temperatures [40][41][42]. Continuing research on understanding the interannual and interseasonal variability of typhoon-induced ARs and their relations to coupled modes of ocean-atmosphere climate variability is therefore recommended.…”

The Comparison of the Tropical Cyclone Number Over the Western North Pacific Between Summer and Autumn

“…As the most active area of tropical cyclones (TCs) in the world, the western North Pacific (WNP) generates an average of about 26 TCs annually, with about 12 TCs landing in the East Asia in the peak season (June to October) (Zhao et al, 2010;Gao et al, 2018;Gao et al, 2020b). The total population of East Asia accounts for about 25% of the world, most of which are concentrated in the southeast coast, such as the relatively developed South China.…”

“…La Niña in the central Pacific inhibits TC generation in the southeast of WNP (Zhang et al, 2012;Wang et al, 2013). In recent years, some studies have pointed out that there is also a close relationship between the tropical North Atlantic (TNA) SST and WNP TC generation activity (Yu et al, 2016;Zhang et al, 2017;Huo et al, 2015;Gao et al, 2018;Gao et al, 2020b). When the cold SST anomaly occurs in TNA, the relative humidity in the South China Sea will increase and the vertical wind shear in the east of WNP will be weakened, forming three anomaly-centers of TC generation frequency in WNP.…”