Articles | Volume 18, issue 6
https://doi.org/10.5194/essd-18-3935-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/essd-18-3935-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Data description article
| 
10 Jun 2026
Data description article |
| 10 Jun 2026
| 10 Jun 2026
A global eddy splitting and merging trajectory dataset based on satellite altimetry utilizing eddygroup, eddytree and eddygraph
Fenglin Tian
School of Marine Technology, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China
Laboratory for Regional Oceanography and Numerical Modeling, Department of Ocean Big Data and Artificial Intelligence, Laoshan Laboratory, Qingdao 266237, China
Xiangwen Kong
School of Marine Technology, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China
Yingying Zhao
School of Marine Technology, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China
Ge Chen
CORRESPONDING AUTHOR
School of Marine Technology, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China
Laboratory for Regional Oceanography and Numerical Modeling, Department of Ocean Big Data and Artificial Intelligence, Laoshan Laboratory, Qingdao 266237, China
Related authors
Fenglin Tian, Yingying Zhao, Lan Qin, Shuang Long, and Ge Chen
Earth Syst. Sci. Data, 17, 7119–7145, https://doi.org/10.5194/essd-17-7119-2025, https://doi.org/10.5194/essd-17-7119-2025, 2025
Short summary
Short summary
Black Hole Eddy (BHE) is vital for transporting materials but were previously hard to identify efficiently. This study introduces an efficient method to identify BHE, 13 times quicker, firstly enables the creation of BHE dataset in the North Pacific from 1993 to 2023. We verified BHE maintains strong coherence and contributes to westward transport about 1.5 Sv. We found some previously unidentified coherent eddies and analyzed their coherence. This represents first comprehensive analysis of BHE.
Shuang Long, Fenglin Tian, Junwu Tang, Fangjie Yu, Fang Zhang, Wei Ma, Xinglong Zhang, and Ge Chen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-276, https://doi.org/10.5194/essd-2025-276, 2025
Revised manuscript not accepted
Short summary
Short summary
Oceanic mesoscale eddies are known to form dipoles from time to time. When dipoles are asymmetric in strength, the stronger dipole eddies generally drive weaker ones to move around, resulting in a reduction of discrepancies in their kinematic properties, which is referred to as the “gear-like” process. An integrated observation of an asymmetric eddy dipole was conducted in the South China Sea in April 2023, which evidences the “gear-like” process.
Xinyuan Xi, Jiahui Chen, Ge Chen, Yuemei Li, Chunyong Ma, and Yijie Gai
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-822, https://doi.org/10.5194/essd-2025-822, 2026
Preprint under review for ESSD
Short summary
Short summary
This study uses the SWOT satellite to detect internal waves across 13 global regions from 2023 to 2025. A deep learning model was developed for automatic detection, creating a dataset of over 3,200 signals. The results show that SWOT outperforms other satellites in data availability, accuracy, and spatial coverage, providing valuable data for oceanographic studies and environmental monitoring.
Fenglin Tian, Yingying Zhao, Lan Qin, Shuang Long, and Ge Chen
Earth Syst. Sci. Data, 17, 7119–7145, https://doi.org/10.5194/essd-17-7119-2025, https://doi.org/10.5194/essd-17-7119-2025, 2025
Short summary
Short summary
Black Hole Eddy (BHE) is vital for transporting materials but were previously hard to identify efficiently. This study introduces an efficient method to identify BHE, 13 times quicker, firstly enables the creation of BHE dataset in the North Pacific from 1993 to 2023. We verified BHE maintains strong coherence and contributes to westward transport about 1.5 Sv. We found some previously unidentified coherent eddies and analyzed their coherence. This represents first comprehensive analysis of BHE.
Jian Hui Li, Jie Yang, and Ge Chen
Biogeosciences, 22, 5635–5650, https://doi.org/10.5194/bg-22-5635-2025, https://doi.org/10.5194/bg-22-5635-2025, 2025
Short summary
Short summary
This study examines how environmental factors, particularly temperature, affect the seasonal and spatial distribution of mesopelagic organisms in the North Atlantic. Using data from 720 BGC-Argo floats, we identified distinct daily and seasonal migration patterns. Temperature was the key driver, followed by salinity and dissolved oxygen. These findings enhance our understanding of mesopelagic ecosystems, with potential implications for fisheries management.
Shuang Long, Fenglin Tian, Junwu Tang, Fangjie Yu, Fang Zhang, Wei Ma, Xinglong Zhang, and Ge Chen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-276, https://doi.org/10.5194/essd-2025-276, 2025
Revised manuscript not accepted
Short summary
Short summary
Oceanic mesoscale eddies are known to form dipoles from time to time. When dipoles are asymmetric in strength, the stronger dipole eddies generally drive weaker ones to move around, resulting in a reduction of discrepancies in their kinematic properties, which is referred to as the “gear-like” process. An integrated observation of an asymmetric eddy dipole was conducted in the South China Sea in April 2023, which evidences the “gear-like” process.
Yan Wang, Ge Chen, Jie Yang, Zhipeng Gui, and Dehua Peng
Earth Syst. Sci. Data, 16, 5737–5752, https://doi.org/10.5194/essd-16-5737-2024, https://doi.org/10.5194/essd-16-5737-2024, 2024
Short summary
Short summary
Mesoscale eddies are ubiquitous in the ocean and account for 90 % of its kinetic energy, but their generation and dissipation are difficult to observe using current remote sensing technology. Our submesoscale eddy dataset, formed by suppressing large-scale circulation signals and enhancing small-scale chlorophyll structures, has important implications for understanding marine environments and ecosystems, as well as improving climate model predictions.
Linyao Ge, Guiyu Wang, Baoxiang Huang, Chuanchuan Cao, Xiaoyan Chen, and Ge Chen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-190, https://doi.org/10.5194/essd-2024-190, 2024
Manuscript not accepted for further review
Short summary
Short summary
High precision in reconstructing sea surface currents is vital for understanding ocean dynamics. Our paper introduces GEST (Geostrophic-Ekman-Stokes-Tide), a 15 m depth sea current product. GEST, generated by a neural network, captures Ekman, geostrophic currents, Stokes drift, and TPXO9 tidal currents. Its design accounts for complex ocean surface dynamics, surpassing OSCAR and GlobCurrent by 10.4 cm/s and 8.81 cm/s, respectively.
Meng Hou, Jie Yang, Ge Chen, Guiyan Han, Yan Wang, and Kai Wu
EGUsphere, https://doi.org/10.5194/egusphere-2023-1735, https://doi.org/10.5194/egusphere-2023-1735, 2023
Preprint archived
Short summary
Short summary
In this study, we mainly utilized BGC-Argo data to investigate the relationships between chlorophyll levels and environmental factors (CPhyto, Nitrate, Temperature and Light) and its underlying dynamic mechanisms of mesoscale eddies in South Pacific Ocean. We show that, the mechanism of chlorophyll levels are different at different depth of seawater.
Yan Wang, Jie Yang, Kai Wu, Meng Hou, and Ge Chen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-138, https://doi.org/10.5194/essd-2023-138, 2023
Revised manuscript not accepted
Short summary
Short summary
Mesoscale eddies are ubiquitous in the ocean and account for 90 % of its kinetic energy, but their generation and dissipation struggle to observe with current remote sensing technology. Our submesoscale eddy dataset, formed by suppressing large-scale circulation signals and enhancing small-scale chlorophyll structures, has important implications for understanding marine environments and ecosystems, as well as improving climate model predictions.
Guiyu Wang, Ge Chen, Chuanchuan Cao, Xiaoyan Chen, and Baoxiang Huang
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-107, https://doi.org/10.5194/essd-2023-107, 2023
Revised manuscript not accepted
Short summary
Short summary
We present an accurate product of ocean surface current at 15 m depth based on multi-scale physical processes. Following a training process using remote sensing observations and in situ data, the derived current field with a 1/4° resolution captures more details neglected in the 1° ones and demonstrates higher accuracy over other global surface current products at low to middle latitudes.
Cited articles
Brokaw, R. J., Subrahmanyam, B., Trott, C. B., and Chaigneau, A.: Eddy Surface Characteristics and Vertical Structure in the Gulf of Mexico from Satellite Observations and Model Simulations, J. Geophys. Res.-Oceans, 125, https://doi.org/10.1029/2019JC015538, 2020.
Chaigneau, A., Gizolme, A., and Grados, C.: Mesoscale eddies off Peru in altimeter records: Identification algorithms and eddy spatio-temporal patterns, Prog. Oceanogr., 79, 106–119, https://doi.org/10.1016/j.pocean.2008.10.013, 2008.
Chelton, D. B., Schlax, M. G., Samelson, R. M., and de Szoeke, R. A.: Global observations of large oceanic eddies, Geophys. Res. Lett., 34, https://doi.org/10.1029/2007gl030812, 2007.
Chelton, D. B., Gaube, P., Schlax, M. G., Early, J. J., and Samelson, R. M.: The Influence of Nonlinear Mesoscale Eddies on Near-Surface Oceanic Chlorophyll, Science, 334, 328–332, https://doi.org/10.1126/science.1208897, 2011a.
Chelton, D. B., Schlax, M. G., and Samelson, R. M.: Global observations of nonlinear mesoscale eddies, Prog. Oceanogr., 91, 167–216, https://doi.org/10.1016/j.pocean.2011.01.002, 2011b.
Chen, G., Yang, J., and Han, G.: Eddy morphology: Egg-like shape, overall spinning, and oceanographic implications, Remote Sens. Environ., 257, https://doi.org/10.1016/j.rse.2021.112348, 2021.
Cheng, Y.-H., Ho, C.-R., Zheng, Q., and Kuo, N.-J.: Statistical Characteristics of Mesoscale Eddies in the North Pacific Derived from Satellite Altimetry, Remote Sens.-Basel, 6, 5164–5183, https://doi.org/10.3390/rs6065164, 2014.
Dong, C., McWilliams, J. C., Liu, Y., and Chen, D.: Global heat and salt transports by eddy movement, Nat. Commun., 5, https://doi.org/10.1038/ncomms4294, 2014.
Faghmous, J. H., Frenger, I., Yao, Y., Warmka, R., Lindell, A., and Kumar, V.: A daily global mesoscale ocean eddy dataset from satellite altimetry, Sci. Data, 2, https://doi.org/10.1038/sdata.2015.28, 2015.
Fang, F. and Morrow, R.: Evolution, movement and decay of warm-core Leeuwin Current eddies, Deep-Sea Res. Pt. II, 50, 2245–2261, https://doi.org/10.1016/s0967-0645(03)00055-9, 2003.
Fu, M., Dong, C., Dong, J., and Sun, W.: Analysis of Mesoscale Eddy Merging in the Subtropical Northwest Pacific Using Satellite Remote Sensing Data, Remote Sens.-Basel, 15, https://doi.org/10.3390/rs15174307, 2023.
Haller, G.: Lagrangian Coherent Structures, Annu. Rev. Fluid Mech., 47, 137–162, https://doi.org/10.1146/annurev-fluid-010313-141322, 2015.
Ioannou, A., Guez, L., Laxenaire, R., and Speich, S.: Global Assessment of Mesoscale Eddies with TOEddies: Comparison Between Multiple Datasets and Colocation with In Situ Measurements, Remote Sens.-Basel, 16, https://doi.org/10.3390/rs16224336, 2024.
Isern-Fontanet, J., García-Ladona, E., and Font, J.: Identification of Marine Eddies from Altimetric Maps, J. Atmos. Ocean. Tech., 20, 772–778, https://doi.org/10.1175/1520-0426(2003)20<772:Iomefa>2.0.Co;2, 2003.
Isoda, Y.: Warm eddy movements in the eastern Japan Sea, J. Oceanogr., 50, 1–15, https://doi.org/10.1007/BF02233852, 1994.
Jones-Kellett, A. E. and Follows, M. J.: A Lagrangian coherent eddy atlas for biogeochemical applications in the North Pacific Subtropical Gyre, Earth Syst. Sci. Data, 16, 1475–1501, https://doi.org/10.5194/essd-16-1475-2024, 2024.
Le Vu, B., Stegner, A., and Arsouze, T.: Angular Momentum Eddy Detection and Tracking Algorithm (AMEDA) and Its Application to Coastal Eddy Formation, J. Atmos. Ocean. Tech., 35, 739–762, https://doi.org/10.1175/jtech-d-17-0010.1, 2018.
Li, Q.-Y., Sun, L., and Lin, S.-F.: GEM: a dynamic tracking model for mesoscale eddies in the ocean, Ocean Sci., 12, 1249–1267, https://doi.org/10.5194/os-12-1249-2016, 2016.
Liu, Y., Chen, G., Sun, M., Liu, S., and Tian, F.: A Parallel SLA-Based Algorithm for Global Mesoscale Eddy Identification, J. Atmos. Ocean. Tech., 33, 2743–2754, https://doi.org/10.1175/jtech-d-16-0033.1, 2016.
Long, S., Tian, F., Ma, Y., Cao, C., and Chen, G.: “Gear-like” process between asymmetric dipole eddies from satellite altimetry, Remote Sens. Environ., 314, https://doi.org/10.1016/j.rse.2024.114372, 2024.
Mason, E., Pascual, A., and McWilliams, J. C.: A New Sea Surface Height–Based Code for Oceanic Mesoscale Eddy Tracking, J. Atmos. Ocean. Tech., 31, 1181–1188, https://doi.org/10.1175/jtech-d-14-00019.1, 2014.
Onu, K., Huhn, F., and Haller, G.: LCS Tool: A computational platform for Lagrangian coherent structures, J. Comput. Sci., 7, 26–36, https://doi.org/10.1016/j.jocs.2014.12.002, 2015.
Pegliasco, C., Delepoulle, A., Mason, E., Morrow, R., Faugère, Y., and Dibarboure, G.: META3.1exp: a new global mesoscale eddy trajectory atlas derived from altimetry, Earth Syst. Sci. Data, 14, 1087–1107, https://doi.org/10.5194/essd-14-1087-2022, 2022.
Sadarjoen, I. A. and Post, F. H.: Detection, quantification, and tracking of vortices using streamline geometry, Comput. Graph., 24, 333-341, https://doi.org/10.1016/S0097-8493(00)00029-7, 2000.
Schouten, M. W., de Ruijter, W. P. M., van Leeuwen, P. J., and Lutjeharms, J. R. E.: Translation, decay and splitting of Agulhas rings in the southeastern Atlantic Ocean, J. Geophys. Res.-Oceans, 105, 21913–21925, https://doi.org/10.1029/1999jc000046, 2000.
Sun, W., Dong, C., Tan, W., Liu, Y., He, Y., and Wang, J.: Vertical Structure Anomalies of Oceanic Eddies and Eddy-Induced Transports in the South China Sea, Remote Sens.-Basel, 10, https://doi.org/10.3390/rs10050795, 2018.
Thompson, A. F., Heywood, K. J., Schmidtko, S., and Stewart, A. L.: Eddy transport as a key component of the Antarctic overturning circulation, Nat. Geosci., 7, 879–884, https://doi.org/10.1038/ngeo2289, 2014.
Tian, F. and Kong, X.: A Global Eddy Splitting and Merging Trajectory Dataset Based on Satellite Altimetry Utilizing Eddygroup, Eddytree and Eddygraph, CASEarth Data Sharing and Service Portal [data set], https://doi.org/10.12237/casearth.20250026, 2025.
Tian, F., Li, Z., Yuan, Z., and Chen, G.: EddyGraph: The Tracking of Mesoscale Eddy Splitting and Merging Events in the Northwest Pacific Ocean, Remote Sens.-Basel, 13, https://doi.org/10.3390/rs13173435, 2021.
Tian, F., Wang, M., Liu, X., He, Q., and Chen, G.: SLA-Based Orthogonal Parallel Detection of Global Rotationally Coherent Lagrangian Vortices, J. Atmos. Ocean. Tech., 39, 823–836, https://doi.org/10.1175/jtech-d-21-0103.1, 2022.
Tian, F., Xiang, H., Long, S., and Chen, G.: Statistical characterization of global eddy splitting and merging events, Periodical of Ocean University of China, 54, 99–110, https://doi.org/10.16441/j.cnki.hdxb.20230070, 2024.
Tian, F., Zhao, Y., Qin, L., Long, S., and Chen, G.: A Black Hole Eddy dataset of North Pacific Ocean based on satellite altimetry, Earth Syst. Sci. Data, 17, 7119–7145, https://doi.org/10.5194/essd-17-7119-2025, 2025.
van Sebille, E., Griffies, S. M., Abernathey, R., Adams, T. P., Berloff, P., Biastoch, A., Blanke, B., Chassignet, E. P., Cheng, Y., Cotter, C. J., Deleersnijder, E., Döös, K., Drake, H. F., Drijfhout, S., Gary, S. F., Heemink, A. W., Kjellsson, J., Koszalka, I. M., Lange, M., Lique, C., MacGilchrist, G. A., Marsh, R., Mayorga Adame, C. G., McAdam, R., Nencioli, F., Paris, C. B., Piggott, M. D., Polton, J. A., Rühs, S., Shah, S. H. A. M., Thomas, M. D., Wang, J., Wolfram, P. J., Zanna, L., and Zika, J. D.: Lagrangian ocean analysis: Fundamentals and practices, Ocean Model., 121, 49–75, https://doi.org/10.1016/j.ocemod.2017.11.008, 2018.
Wang, H., Qiu, B., Liu, H., and Zhang, Z.: Doubling of surface oceanic meridional heat transport by non-symmetry of mesoscale eddies, Nat. Commun., 14, https://doi.org/10.1038/s41467-023-41294-7, 2023.
Williams, S., Hecht, M., Petersen, M., Strelitz, R., Maltrud, M., Ahrens, J., Hlawitschka, M., and Hamann, B.: Visualization and Analysis of Eddies in a Global Ocean Simulation, Comput. Graph. Forum, 30, 991–1000, https://doi.org/10.1111/j.1467-8659.2011.01948.x, 2011.
Xia, Q., Dong, C., He, Y., Li, G., and Dong, J.: Lagrangian Study of Several Long-Lived Agulhas Rings, J. Phys. Oceanogr., 52, 1049–1072, https://doi.org/10.1175/jpo-d-21-0079.1, 2022.
Xing, T. and Yang, Y.: Three Mesoscale Eddy Detection and Tracking Methods: Assessment for the South China Sea, J. Atmos. Ocean. Tech., 38, 243–258, https://doi.org/10.1175/jtech-d-20-0020.1, 2021.
Xu, C., Shang, X.-D., and Huang, R. X.: Estimate of eddy energy generation/dissipation rate in the world ocean from altimetry data, Ocean Dynam., 61, 525–541, https://doi.org/10.1007/s10236-011-0377-8, 2011.
Xu, L., Li, P., Xie, S.-P., Liu, Q., Liu, C., and Gao, W.: Observing mesoscale eddy effects on mode-water subduction and transport in the North Pacific, Nat. Commun., 7, https://doi.org/10.1038/ncomms10505, 2016.
Yao, H., Ma, C., Jing, Z., and Zhang, Z.: On the Vertical Structure of Mesoscale Eddies in the Kuroshio-Oyashio Extension, Geophys. Res. Lett., 50, https://doi.org/10.1029/2023gl105642, 2023.
Zhang, Z., Wang, W., and Qiu, B.: Oceanic mass transport by mesoscale eddies, J. Science, 345, 322–324, https://doi.org/10.1126/science.1252418, 2014.
Zhao, H. J., Misko, V. R., Tempere, J., and Nori, F.: Pattern formation in vortex matter with pinning and frustrated inter-vortex interactions, Phys. Rev. B, 95, 104519, https://doi.org/10.1103/PhysRevB.95.104519, 2017.
Zhou, X., Li, Q., Yu, X., Zhang, G., and Ma, Y.: The three-dimensional composite analysis method of mesoscale eddies in the Philippine Sea based on sound speed profile clustering, Frontiers in Marine Science, 12, https://doi.org/10.3389/fmars.2025.1557271, 2025.
Short summary
We developed a global method to identify and track ocean mesoscale eddies using satellite data from 1993 to 2023 and generated the corresponding dataset. The analysis reveals stable and persistent eddytree structures linked to major ocean currents. It also shows that common eddygroup boundaries play a key role in how eddies split and merge, highlighting the reciprocal nature of these dynamic ocean processes.
We developed a global method to identify and track ocean mesoscale eddies using satellite data...
Altmetrics
Final-revised paper
Preprint