Modeled MABL Responses to the Winter Kuroshio SST Front in the East China Sea and Yellow Sea

Abstract

Based on the Weather Research Forecasting (WRF) model, we designed a long‐term sea surface temperature (SST)‐forcing simulation to simulate the influences of SST front on the marine atmospheric boundary layer (MABL) over the East China Sea and the Yellow Sea during wintertime. The results revealed that SST front have significant relationship with MABL adjustment. The atmospheric modulations and the comparisons of the vector wind and the scalar wind indicate that the MABL responses to the SST front are quite different under different wind directions. When the prevailing wind blows parallel to the SST front (NE wind directions), the sea level pressure adjustment mechanism dominates the atmospheric adjustment. The variances of scalar wind and vector wind are similar. However, when prevailing wind crossing SST front from cold to warm (NW wind directions), both the sea level pressure adjustment mechanism and vertical mixing mechanism play an important role. The maximum variations of the scalar wind are just over the core of SST front, whereas maximum vector wind variations are over warm flank. When wind blowing from warm to cold (SE wind directions), the vertical mixing mechanism contributes more to the MABL responses. The maximum variations of the scalar wind are beyond the top of MABL, which occur over the core SST front. The further diagnosis analysis showed that the meridional transient eddies and mean flow interaction contribute to the scalar wind variations under cross‐front conditions.

Synergistic Effects of Midlatitude Atmospheric Upstream Disturbances and Oceanic Subtropical Front Intensity Variability on Western Pacific Jet Stream in Winter

“…M. Xu & Xu, 2015;Tokinaga et al, 2006). A homomorphic relationship between SST and surface wind was observed in the Antarctic Circumpolar Current region (Annis & White, 2003), the Somali Current region (Vecchi et al, 2004), the Gulf Stream region (Parfitt et al, 2016) and the Kuroshio Extension region (Bai et al, 2019(Bai et al, , 2020Hirata et al, 2016;Yao et al, 2016).…”

“…However, a completely different SST‐wind relationship was found over the small‐scale SST front regions, which represents the forcing from the ocean to the atmosphere in the midlatitude (H. M. Xu et al, 2011; J. W. Liu et al, 2013; M. M. Xu & Xu, 2015; Tokinaga et al, 2006). A homomorphic relationship between SST and surface wind was observed in the Antarctic Circumpolar Current region (Annis & White, 2003), the Somali Current region (Vecchi et al, 2004), the Gulf Stream region (Parfitt et al, 2016) and the Kuroshio Extension region (Bai et al, 2019, 2020; Hirata et al, 2016; Yao et al, 2016).…”

Local and remote forcing effects of oceanic eddies in the subtropical front zone on the mid-latitude atmosphere in Winter

“…The interaction between the ocean and the atmosphere is the focus of attention in atmospheric dynamics and climate research. It is long been a hot and controversial topic for the air-sea interaction in the mid-latitude, especially for the oceanic forcing on atmosphere (Nakamura et al, 1997;Chelton et al, 2001;Di Lorenzo et al, 2008;Wang et al, 2019;Bai et al, 2019). In the mid-latitude North Pacific, air-sea interaction events can be divided into macroscale climate variability, such as the Pacific Decadal Oscillation (PDO) events, and mesoscale, e.g., the impact of oceanic fronts and eddies on the atmosphere above.…”

“…Relatively, the forcings of oceanic fronts and eddies to the atmosphere are considered as the representative mesoscale air-sea interactions in the North Pacific (Nakamura et al, 1997;Minobe et al, 2008;Wang et al, 2019;Chen et al, 2019a;Bai et al, 2019Bai et al, , 2020. In the mid-latitude region, the difference between the forcing effects of oceanic fronts and eddies on the atmosphere and the specific physical process remain to be clarified.…”

Different Influences of Mesoscale Oceanic Eddies on the North Pacific Subsurface Low Potential Vorticity Water Mass Between Winter and Summer

“…Subtropical mode water (STMW) is one of the widely studied SLPVW. In winter subtropical ocean basin, there is a large oceanic heat loss due to the atmospheric cooling over the warm sea surface, especially over the warm side of the Kuroshio or Gulf Stream fronts (Chen et al, ; Bai et al, ). The deep convective mixing which is relevant to the wind stress and oceanic heat loss, makes the mixed layer depth (MLD) reaching the maximum in late winter.…”