Interannual and Interdecadal Variations of the Western North Pacific Monsoon and Baiu Rainfall and their Relationship to the ENSO Cycles

For decades, the western North Pacific (WNP) has been commonly indicated as a region with high vulnerability to oceanic and atmospheric hazards. This phenomenon can be observed through general circulation model (GCM) output from the Coupled Model Intercomparison Project (CMIP). The CMIP consists of a collection of ensemble data as well as marine surface winds for the projection of the wave climate. Wave climate projections based on the CMIP dataset are necessary for ocean studies, marine forecasts, and coastal development over the WNP region. Numerous studies with earlier phases of CMIP are abundant, but studies using CMIP6 as the recent dataset for wave projection is still limited. Thus, in this study, wave climate projections with WAVEWATCH III are conducted to investigate how wave characteristics in the WNP will have changed in 2050 and 2100 compared to those in 2000 with atmospheric forcings from CMIP6 marine surface winds. The wave model runs with a 0.5° × 0.5° spatial resolution in spherical coordinates and a 10-min time step. A total of eight GCMs from the CMIP6 dataset are used for the marine surface winds modelled over 3 hours for 2050 and 2100. The simulated average wave characteristics for 2000 are validated with the ERA5 Reanalysis wave data showing good consistency. The wave characteristics in 2050 and 2100 show that significant decreases in wave height, a clockwise shift in wave direction, and the mean wave period becomes shorter relative to those in 2000.

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Relationship of tropical cyclone size change rate with size and intensity over the western North Pacific

Atmospheric and Oceanic Science Letters ◽

10.1016/j.aosl.2021.100040 ◽

2021 ◽

pp. 100040

Author(s):

Kexin Chen ◽

Guanghua Chen ◽

Chenhong Rao ◽

Ziqing Wang

Keyword(s):

Tropical Cyclone ◽

North Pacific ◽

Western North Pacific ◽

Size Change ◽

Change Rate ◽

Relationship Of

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Lateral variations of 134Cs and 228Ra concentrations in surface waters in the western North Pacific and its marginal sea (2018–2019): Implications for basin-scale and local current circulations

Progress In Oceanography ◽

10.1016/j.pocean.2021.102587 ◽

2021 ◽

pp. 102587

Author(s):

Mutsuo Inoue ◽

Shotaro Hanaki ◽

Ryosei Takehara ◽

Hisaki Kofuji ◽

Tetsuya Matsunaka ◽

...

Keyword(s):

Surface Waters ◽

North Pacific ◽

Western North Pacific ◽

Marginal Sea ◽

Basin Scale ◽

Local Current ◽

Lateral Variations

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Tropical cyclones over the western north Pacific since the mid-nineteenth century

Climatic Change ◽

10.1007/s10584-021-02984-7 ◽

2021 ◽

Vol 164 (3-4) ◽

Author(s):

Hisayuki Kubota ◽

Jun Matsumoto ◽

Masumi Zaiki ◽

Togo Tsukahara ◽

Takehiko Mikami ◽

...

Keyword(s):

Nineteenth Century ◽

East China Sea ◽

North Pacific ◽

Western North Pacific ◽

East China ◽

Pressure Data ◽

The East China Sea ◽

China Sea ◽

Spatial Coverage ◽

Landfall Location

AbstractTropical cyclone (TC) activities over the western North Pacific (WNP) and TC landfall in Japan are investigated by collecting historical TC track data and meteorological observation data starting from the mid-nineteenth century. Historical TC track data and TC best track data are merged over the WNP from 1884 to 2018. The quality of historical TC data is not sufficient to count the TC numbers over the WNP due to the lack of spatial coverage and different TC criteria before the 1950s. We focus on TC landfall in Japan using a combination of TC track data and meteorological data observed at weather stations and lighthouses from 1877 to 2019. A unified TC definition is applied to obtain equivalent quality during the whole analysis period. We identify lower annual TC landfall numbers during the 1970s to the 2000s and find other periods have more TC landfall numbers including the nineteenth century. No trend in TC landfall number is detected. TC intensity is estimated by an annual power dissipation index (APDI). High APDI periods are found to be around 1900, in the 1910s, from the 1930s to 1960s, and after the 1990s. When we focus on the period from 1977 to 2019, a significant increasing trend of ADPI is seen, and significant northeastward shift of TC landfall location is detected. On the other hand, TC landfall location shifts northeastward and then southwestward in about 100-year interval. European and US ships sailed through East and Southeast Asian waters before the weather station network was established in the late nineteenth century. Then, we focus on TC events in July 1853 observed by the US Naval Japan Expedition of Perry’s fleet and August 1863 by a UK Navy ship that participated in two wars in Japan. A TC moved slowly westward over the East China Sea south of the Okinawa Islands from 21 to 25 July 1853. Another TC was detected in the East China Sea on 15–16 August 1863 during the bombardment of Kagoshima in southern Japan. Pressure data are evaluated by comparing the observations made by 10 naval ships in Yokohama, central Japan during 1863–1864. The deviation of each ship pressure data from the 10 ships mean is about 2.7–2.8 hPa.

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