Review
Meteorology & Atmospheric Sciences
Guidi Zhou, Xuhua Cheng
Summary: This paper reviews the progress in understanding the atmospheric response to midlatitude oceanic fronts and eddies, with a focus on the Kuroshio-Oyashio Extension (KOE) region. Oceanic fronts play a significant role in maintaining the storm track, but current research is still subject to uncertainties arising from inadequate data resolution.
ADVANCES IN ATMOSPHERIC SCIENCES
(2022)
Article
Environmental Sciences
Wei Cui, Jungang Yang, Yongjun Jia, Jie Zhang
Summary: Vigorous mesoscale eddies, identified from sea surface height and sea surface temperature, are widely distributed in the Kuroshio Extension. The correlation between sea surface temperature anomaly (SSTA) and sea surface height anomaly (SSHA) inside eddies is higher in winter than in summer. The lifetime and propagation distance of SSTA-based eddies are shorter and smaller than those of SSHA-based eddies. SSHA-based eddies are primarily found in the Kuroshio mainstream, while SSTA-based eddies are concentrated in the Oyashio Extension, where SST gradient is large and changes in SST fields caused by eddies are more obvious.
Article
Environmental Sciences
Jianxiang Sun, Suping Zhang, Yuxi Jiang, Yanshuo Wang, Baoqin Wu, Haijiao Wang
Summary: This study investigates the responses of the East Asian Trough to the Kuroshio Extension interannual fluctuation and identifies the underlying mechanisms. The observations show that the stable state of the Kuroshio Extension corresponds to a deeper East Asian Trough, accompanied by a stronger winter monsoon. Atmospheric Rossby waves, transient eddies, and thermal winds are found to be responsible for this relationship.
Article
Geosciences, Multidisciplinary
Chaohui Chen, Jianqi Zhang, Xiangguo Chen
Summary: This study investigates the response of North Pacific storm tracks to spatial multiscale sea surface temperature anomalies in the stable state of the Kuroshio Extension system. The results show that the storm tracks are significantly strengthened and cause increased rainfall in certain areas in response to large-scale temperature anomalies, while they shift to the north and strengthen in other areas in response to mesoscale temperature anomalies, with remote impact on precipitation along the west coast of North America.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Engineering, Marine
Haitong Wang, Yunxia Guo, Yuan Kong, Yong Fang
Summary: A data-driven machine learning model, TMENN, is proposed to forecast the spatiotemporal variation of mesoscale eddies in the Kuroshio Extension. By decomposing sea surface height data and selecting principal components as predictors, the model can reliably forecast the evolution of eddies and accurately capture the mesoscale eddy processes.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Environmental Sciences
Xinyu Zhang, Hua Zheng, Xiao-Hua Zhu, Ruixiang Zhao, Cong Xiao, Min Wang, Juntian Chen
Summary: The study investigates a supercharged cold eddy with strong temperature anomaly in the Kuroshio Extension region. The three-dimensional structure of the eddy is continuously observed for 83 days, showing stable characteristics in terms of radius, depth and speed. The analysis reveals that the eddy energy mainly originates from the Kuroshio and is enhanced by baroclinic and barotropic conversion.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Oceanography
Hui Zhang, Qiang Wang, Mu Mu, Xia Liu
Summary: This study investigates the short-term transition process between the stable and unstable states of the Kuroshio Extension (KE) using eddy energetics analysis. The study reveals the local dynamic mechanisms that modulate the transitions and provides insights into the factors affecting the growth and reduction of eddy kinetic energy (EKE) in the KE.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Yao Meng, Hailong Liu, Ruiqiang Ding, Pengfei Lin, Mengrong Ding, Pengfei Wang
Summary: In this study, the nonlinear local Lyapunov exponent and nonlinear error growth dynamics were used to quantitatively estimate the predictability limit of oceanic mesoscale eddy (OME) tracks. The results showed that the predictability limit of OME tracks varied spatially, with the eastern region having higher limits. The predictability limit of OME tracks was closely related to the lifetime, amplitude, and radius of the eddies.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Yuhan Cao, Changming Dong, Zehao Qiu, Brandon J. Bethel, Haiyun Shi, Haibin Lue, Yinhe Cheng
Summary: Oceanic datasets derived from satellite altimeters are important for studying physical oceanography, ocean dynamics, and marine environmental protection. This study introduces an iterative method to correct surface velocities of mesoscale eddies derived from altimeters by considering the ageostrophic velocity induced by centrifugal force. The results show that cyclogeostrophic correction is necessary for eddies with small curvature radii, high roundness, or a Rossby number larger than 0.1. The iterative method is also applied to correct multi-year Kuroshio surface velocities, showing a significant effect on the Kuroshio Extension region.
Article
Environmental Sciences
Eko Siswanto, Yoshikazu Sasai, Kazuhiko Matsumoto, Makio C. Honda
Summary: By analyzing ocean color data, we found that the instability of the Kuroshio Extension affects the phenology of phytoplankton during winter-spring. Unstable Kuroshio Extension leads to higher chlorophyll-a (CHL) levels during winter and spring, due to increased nutrient and light availability. This finding suggests that the instability of the Kuroshio Extension may have implications for higher trophic level organisms in the ecosystem.
Article
Meteorology & Atmospheric Sciences
Yao Meng, Hailong Liu, Pengfei Lin, Mengrong Ding, Changming Dong
Summary: Different datasets show discrepancies in identifying eddy numbers and locations, but more than 50% of identified eddies overlap. GEM-M can identify more eddies with a segmentation algorithm, while Chelton identifies fewer eddies due to tracking errors and longer lifespan. The geographic distributions and temporal variations of eddy features are highly similar among the datasets, particularly Chelton, Fahgmous, and Dong.
ATMOSPHERIC AND OCEANIC SCIENCE LETTERS
(2021)
Article
Environmental Sciences
Mingyue Liu, Ru Chen, Wenting Guan, Hong Zhang, Tian Jing
Summary: This study aims to estimate and predict the nonlocality of scale-dependent eddy mixing in the Kuroshio Extension region. It found that the nonlocality of mixing is prevalent and becomes more significant with higher resolution. The random forest approach is better at representing the nonlocality of scale-dependent mixing.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Guidi Zhou, Zhuhua Li, Xuhua Cheng
Summary: This research utilizes satellite altimeter observations to investigate the decadal variability mechanism of the Kuroshio Extension (KE), uncovering the energy feedback between the jet and mesoscale eddies that sustains the decadal oscillation. The study also reveals that wind-driven sea surface height anomalies are weaker and broader compared to intrinsic variability, suggesting a complex relationship with low statistical significance. Additionally, perturbations in KE induced by intrinsic variability could potentially feedback onto wind-driven SSHAs through anomalous basin-scale wind stress.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Oceanography
Mingkun Lv, Fan Wang, Yuanlong Li, Zhengguang Zhang, Yanan Zhu
Summary: This study investigates the characteristics and generation mechanisms of mesoscale sea surface temperature anomalies induced by oceanic mesoscale eddies and demonstrates that lateral stirring plays a more important role than vertical pumping in causing these anomalies.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Cristy S. Acabado, Yu-Hsin Cheng, Ming-Huei Chang, Chung-Chi Chen
Summary: The study shows that Kelvin-Helmholtz billows play a significant role in influencing vertical nitrate fluxes and promoting microscale turbulent mixing around seamounts in the Kuroshio. Billow intensity affects nitrate fluxes, with higher values found in the billow depths contributing to the growth of phytoplankton communities. The depth and proximity of the billows to the seafloor also impact the distribution of nitrate fluxes.
FRONTIERS IN MARINE SCIENCE
(2021)