Abstract Submesoscale density fronts and the associated processes of frontogenesis symmetric instability (SI) are investigated in northwest Pacific subtropical countercurrent (STCC) system by a high-resolution simulation diagnostic analysis. Both satellite observations realistic show active surface with horizontal scale ~20 km STCC upper ocean. Frontogenesis-induced buoyancy advection is detected to rapidly sharpen these fronts. The direct straining effect larger-scale geostrophic flows...

Abstract The submesoscale energy budget is complex and remains understood only in region-by-region analyses. Based on a series of nested numerical simulations, this study investigated the flux upper ocean Kuroshio Extension, including some innovations for examining budgets general. highest-resolution simulation ~500 m grid resolves variety instabilities allowing an energetic analysis range. frequency–wavenumber spectra vertical vorticity variance (i.e., enstrophy) horizontal divergence were...

Abstract Mesoscale and submesoscale processes have crucial impacts on ocean biogeochemistry, importantly enhancing the primary production in nutrient‐deficient regions. Yet, intricate biophysical interplay still holds mysteries. Using targeted high‐resolution situ observations South China Sea, we reveal that isopycnal stirring serves as driver of vertical nutrient transport to sustain dome‐shaped subsurface chlorophyll maximum (SCM) within a long‐lived cyclonic mesoscale eddy. Density...

Abstract Submesoscale dynamics below the mixed layer (ML) and their mechanisms are still unclear. By a series of nested simulations in Pacific Northwest with high horizontal resolution ∼500 m, this study reveals that there exist strong submesoscale ageostrophic motions upper pycnocline Kuroshio Extension region. These exhibit enhanced lateral buoyancy gradient vigorous vertical velocity but weak vorticity distinct from ML activities. The high‐resolution simulation reaches tens meters per...

Abstract Oceanic motions across meso‐, submeso‐, and turbulent scales play distinct roles in vertical heat transport (VHT) between the ocean's surface its interior. While it is commonly understood that during summertime enhanced stratification due to increased solar radiation typically results an reduced upper‐ocean exchange, our study reveals a significant upward VHT associated with submesoscale fronts (<30 km) through high‐resolution observations eddy‐active South China Sea. The...

Abstract The eddy‐abundant circulation in the northern South China Sea (NSCS) tends to be dynamically complex due monsoon forcing, Kuroshio intrusion, and emitted internal waves from Luzon Strait. This study uses 13‐year shipboard acoustic Doppler current profiler measurements (2004–2016), orbital altimeter data, high‐resolution model output perform wave‐vortex decompositions investigate scale of transition dominantly geostrophic flows wave motions Sea. upper ocean kinetic energy spectra on...

Cao, H.; Chen, Y.; Tian, Y., and Feng, W., 2016. Field investigation into wave attenuation in the mangrove environment of South China Sea coast. Coastal mangroves form land-sea interface face an increasingly aggressive threat from ocean waves as a result sea-level rise. This study investigates buffering effect on coast Leizhou Bay under two different climates (normal windy weather storm). By doing this, we aim to establish exact damping rate due presence spectral characteristics energy...

The classical theory predicts that a geostrophically balanced mesoscale eddy can cause sea surface temperature (SST) anomaly related to Ekman pumping. Previous studies show an eddy-induced SST result in latent heat flux (LH) at maximum magnitude of ∼ O (10) Wm –2 , decaying radially outward from the center margin. In this study, we investigate LH anomalies associated with submesoscale processes within cyclonic for first time using recent satellite-ship-coordinated air-sea observations South...

Abstract This study investigates the seasonal features and generation mechanisms of submesoscale processes (SMPs) in southern Bay Bengal (BoB) during 2011/12, based on output a high-resolution model, LLC4320 (latitude–longitude–polar cap). The results show that BoB exhibits most energetic SMPs, with significant variations. SMPs are more active summer winter monsoon periods. During periods, sharpening horizontal buoyancy gradients associated strong straining effects favor frontogenesis mixed...

Abstract The evolution and dynamics of an initially Gaussian baroclinic vortex embedded in a resting stratification environment are investigated with three-dimensional primitive equation model. process strongly depends on multiple parameters. Particularly, the effects gradient planetary vorticity, nonlinearity, friction have been studied to evaluate their roles. Comparisons previous results from simplified model made. We particularly focus interactions between vortices at different levels...

Abstract Oceanic submesoscale dynamics with horizontal scales < 20 km have similar temporal and spatial as internal gravity waves (IGWs), but they differ dynamically distinct impacts on the ocean. Separating unbalanced motions (USMs), quasi-balanced (QBMs), IGWs in observations remains a great challenge. Based wave–vortex decomposition vertical scale separation approach for distinguishing USMs, long-term repeat Oleander Gulf Stream region provide an opportunity to quantify these processes...

With global climate change, the risk of extreme storms and storm surges in estuarine areas is increasing; thus, surge inundation research prediction have become important issues to ensure sustainable development areas. The Jitimen estuary Guangdong Province, China, was chosen as our study area. In this study, a numerical model for simulating small regions based on unstructured triangular grids established, accuracy validated. typhoon characteristics area were statistically analyzed...

Qualitative precipitation forecasting plays a vital role in marine operational services. However, predicting heavy over the open ocean presents significant challenge due to limited availability of ground-based radar observations far from coastal regions. Recent advancements deep learning models offer potential for oceanic nowcasting using satellite images. This study implemented an enhanced UNet model with attention mechanism and residual architecture (RA-UNet) predict rate within 90 min...

Abstract In the mid‐latitude North Pacific, wintertime ocean heat loss reaches maximum in Kuroshio‐Oyashio Extension (KOE) region. However, mixed layer depth (MLD) there is shallow (<50 m), flanked by a zonal band of deep MLD (>100 m) on either side. Such an observed pattern not reproduced coarse‐resolution or mesoscale eddy‐resolving (1/10°) models. What causes shoaling along KOE frontal region? Here we show that front well 1/30°, submesoscale‐permitting general circulation model,...

Cao, H.; Feng, W., and Chen, Y., 2016. Numerical modeling of wave transformation runup reduction by the coastal vegetation South China Sea. Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., McCarroll, R.J. (eds.), Proceedings 14th International Coastal Symposium (Sydney, Australia). Journal Research, Special Issue, No. 75, pp. 830–835. Coconut Creek (Florida), ISSN 0749-0208.The aim this study is to examine using a numerical model conditions including vegetation. Based on previous field study,...

The South China Sea (SCS) experiences severe typhoon impact every year. That also cause extreme wind waves. estimate of wave height is great importance for human activities in the SCS. Since generation still unpredictable, it very difficult to storm In this paper, we did a statistics analysis tropical cyclones that can affect Based on hindcast simulation, use generalized Pareto distribution (GPD) method height, and discuss determination threshold parameters. It found GPD more favourable...