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1. An Examination of Geomagnetic Induction in Submarine Cables

   https://doi.org/10.1029/2023SW003687  

   Boteler, David H; Chakraborty, Shibaji; Shi, Xueling; Hartinger, Michael D; Wang, Xuan (February 2024, Space Weather)

   Abstract Submarine cables have experienced problems during extreme geomagnetic disturbances because of geomagnetically induced voltages adding or subtracting from the power feed to the repeaters. This is still a concern for modern fiber‐optic cables because they contain a copper conductor to carry power to the repeaters. This paper provides a new examination of geomagnetic induction in submarine cables and makes calculations of the voltages experienced by the TAT‐8 trans‐Atlantic submarine cable during the March 1989 magnetic storm. It is shown that the cable itself experiences an induced electromotive force (emf) and that induction in the ocean also leads to changes of potential of the land at each end of the cable. The process for calculating the electric fields induced in the sea and in the cable from knowledge of the seawater depth and conductivity and subsea conductivity is explained. The cable route is divided into 9 sections and the seafloor electric field is calculated for each section. These are combined to give the total induced emf in the cable. In addition, induction in the seawater and leakage of induced currents through the underlying resistive layers are modeled using a transmission line model of the ocean and underlying layers to determine the change in Earth potentials at the cable ends. The induced emf in the cable and the end potentials are then combined to give the total voltage change experienced by the cable power feed equipment. This gives results very close to those recorded on the TAT‐8 cable in March 1989. 

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2. Optical polarization–based seismic and water wave sensing on transoceanic cables

   https://doi.org/10.1126/science.abe6648  

   Zhan, Zhongwen; Cantono, Mattia; Kamalov, Valey; Mecozzi, Antonio; Müller, Rafael; Yin, Shuang; Castellanos, Jorge C. (February 2021, Science)

   null (Ed.)

   Seafloor geophysical instrumentation is challenging to deploy and maintain but critical for studying submarine earthquakes and Earth’s interior. Emerging fiber-optic sensing technologies that can leverage submarine telecommunication cables present an opportunity to fill the data gap. We successfully sensed seismic and water waves over a 10,000-kilometer-long submarine cable connecting Los Angeles, California, and Valparaiso, Chile, by monitoring the polarization of regular optical telecommunication channels. We detected multiple moderate-to-large earthquakes along the cable in the 10-millihertz to 5-hertz band. We also recorded pressure signals from ocean swells in the primary microseism band, implying the potential for tsunami sensing. Our method, because it does not require specialized equipment, laser sources, or dedicated fibers, is highly scalable for converting global submarine cables into continuous real-time earthquake and tsunami observatories. 

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3. Threading the Ocean: Mapping Digital Routes Across Submarine Cables using Calypso

   https://doi.org/10.1145/3718958.3750512  

   Wang, Caleb; Zhang, Ying; Dong, Qianli; Carisimo, Esteban; Durairajan, Ramakrishnan; Bustamante, Fabián E (August 2025, ACM)

   The Internet's connectivity relies on a fragile submarine cable network (SCN), yet existing tools fall short in assessing its criticality. We introduce Calypso, a new framework that leverages traceroute data to map traffic to submarine cables. Validated through real-world case studies, Calypso reveals hidden risks and offers new insights to enhancing SCN resilience. 

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4. Calypso’s Voyage: Charting Traceroute Paths Through Submarine Cables

   Wang, Caleb; Zhang, Ying; Dong, Qianli; Carisimo, Esteban; Durairajan, Ramakrishnan; Bustamante, Fabian E (October 2026, ACM)

   As the backbone of global Internet connectivity, the submarine cable network (SCN) faces growing threats with serious economic and security implications. Strengthening its resilience requires a clear understanding of which cables and landing points are most critical. This depends on accurately mapping traffic onto the underlying infrastructure to identify vulnerabilities and assess their regional and global impact. Yet existing methods often lack the resolution and fidelity needed for such analysis, leaving researchers and policymakers without the insights to safeguard this vital system. This paper introduces Calypso, a framework for mapping traceroute paths to the submarine cables they traverse. Calypso integrates ownership records, routing metadata, and geographic constraints to infer cable usage despite the opacity of the SCN and challenges such as route virtualization and inland infrastructure. It also defines Route Stress, a traceroute-derived metric for estimating the relative importance of submarine cables. Through expert validation, failure analysis, and regional case studies, we demonstrate Calypso’s utility in revealing SCN dependencies and informing resilience efforts. 

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5. Parameter Identification of Wind-induced Buffeting Loads and Onset Criteria for Dry-cable Galloping of Yawed/inclined Cables

   https://doi.org/10.1016/j.engstruct.2018.11.049  

   Jafari, M.; Sarkar, P.P. (January 2019, Engineering structures)

   null (Ed.)

   Cables of suspension, cable-stayed and tied-arch bridges, suspended roofs, and power transmission lines are prone to moderate to large-amplitude vibrations in wind because of their low inherent damping. Structural or fatigue failure of a cable, due to these vibrations, pose a significant threat to the safety and serviceability of these structures. Over the past few decades, many studies have investigated the mechanisms that cause different types of flow-induced vibrations in cables such as rain-wind induced vibration (RWIV), vortex-induced vibration (VIV), iced cable galloping, wake galloping, and dry-cable galloping that have resulted in an improved understanding of the cause of these vibrations. In this study, the parameters governing the turbulence-induced (buffeting) and motion-induced wind loads (self-excited) for inclined and yawed dry cables have been identified. These parameters facilitate the prediction of their response in turbulent wind and estimate the incipient condition for onset of dry-cable galloping. Wind tunnel experiments were performed to measure the parameters governing the aerodynamic and aeroelastic forces on a yawed dry cable. This study mainly focuses on the prediction of critical reduced velocity 〖(RV〗_cr) as a function of equivalent yaw angle (*) and Scruton number (Sc) through measurement of aerodynamic- damping and stiffness. Wind tunnel tests using a section model of a smooth cable were performed under uniform and smooth/gusty flow conditions in the AABL Wind and Gust Tunnel located at Iowa State University. Static model tests for equivalent yaw angles of 0º to 45º indicate that the mean drag coefficient 〖(C〗_D) and Strouhal number (St) of a yawed cable decreases with the yaw angle, while the mean lift coefficient 〖(C〗_L) remains zero in the subcritical Reynolds number (Re) regime. Dynamic one degree-of-freedom model tests in across-wind and along-wind directions resulted in the identification of buffeting indicial derivative functions and flutter derivatives of a yawed cable for a range of equivalent yaw angles. Empirical equations for mean drag coefficient, Strouhal number, buffeting indicial derivative functions and critical reduced velocity for dry-cable galloping are proposed for yawed cables. The results indicate a critical equivalent yaw angle of 45° for dry-cable galloping. A simplified design procedure is introduced to estimate the minimum damping required to arrest dry-cable galloping from occurring below the design wind speed of the cable structure. Furthermore, the results from this study can be applied to predict the wind load and response of a dry cable at a specified wind speed for a given yaw angle. 

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