Preprints
Filtering by Subject: Oceanography
Spatiotemporal evolution of temperature extremes across India’s agro-climatic zones (1951–2025)
Published: 2026-04-11
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography
Long-term changes in temperature extremes are a robust signature of anthropogenic climate change, yet their spatial structure across India’s agro-climatic zones (ACZs) remains insufficiently resolved at policy scales. Here, we quantify changes in temperature extremes across 14 mainland ACZs during 1951–2025 using the India Meteorological Department 1°×1° gridded daily dataset. We compute 22 [...]
Seasonal Shift in the Dominant Pathway Energizing Mesoscale Eddies in the California Current
Published: 2026-04-08
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Mesoscale eddies are the dominant reservoir of kinetic energy in the ocean, yet the mechanisms that generate and maintain them in eastern boundary current systems remain incompletely assessed. Here we use a 1-km resolution simulation of the California Current System (CCS) to diagnose and quantify the processes that supply kinetic energy to the mesoscale band. A pronounced seasonal transition is [...]
Introducing Microalgae Carbon Fixation and Sinking (MCFS): a new approach for controlled and scalable CDR
Published: 2026-04-08
Subjects: Biogeochemistry, Climate, Oceanography, Other Oceanography and Atmospheric Sciences and Meteorology
Achieving global climate targets requires scalable and durable carbon dioxide removal (CDR) technologies to tackle both historical and hard-to- abate emissions. We introduce Microalgae Carbon Fixation and Sinking (MCFS), a marine CDR methodology designed to enhance carbon fixation and export to the deep ocean through a controlled process. At the core of the MCFS approach is a tailored substrate: [...]
A new diagnostic of air-sea interaction reveals ocean control of turbulent heat flux in the South Asian Summer Monsoon
Published: 2026-04-02
Subjects: Atmospheric Sciences, Climate, Oceanography
Air-sea interaction plays a central role in the South Asian summer monsoon, with processes such as surface turbulent heat fluxes, upper ocean mechanical mixing, surface buoyancy forcing, and surface moisture fluxes providing bridges between the ocean and atmosphere. The air-sea heat flux responds to internal variability in the ocean and atmosphere, as well as feedbacks arising from their [...]
The Hermatz Effect: A Five-Layer Solar–Geo Dynamo Model for the Persistent 0.038 Hz Global Seismic Signal
Published: 2026-03-30
Subjects: Astrophysics and Astronomy, Atmospheric Sciences, Condensed Matter Physics, Earth Sciences, Environmental Chemistry, Fluid Dynamics, Geology, Geomorphology, Geophysics and Seismology, Hydrology, Meteorology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Astrophysics and Astronomy, Other Physics, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Hydrology, Tectonics and Structure, The Sun and the Solar System
Earth produces a faint but globally detectable vibration at a period of exactly 26 seconds, and no one has fully explained why. This paper proposes that it comes from a crack in the ocean floor off West Africa acting like a tuned whistle — the ocean blows air through it, the crack vibrates at its natural frequency, and the vibration travels around the entire planet as a seismic wave. Occasionally [...]
The Oceanic Response to Winds in the Antarctic Sea Ice Loss at the end of the 1970s
Published: 2026-03-28
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The sea ice extent (SIE) in the Southern Ocean experienced a substantial decline in the late 1970s, although less pronounced than the one observed in 2016. Though several studies explain the decline since 2016, the 1970s drop is critical in understanding the long-term variability of SIE. To investigate the underlying mechanisms for this decline, we conducted wind stress-forced multi- ensemble [...]
A universal law for non-breaking surface wave decay
Published: 2026-03-22
Subjects: Fluid Dynamics, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics, Statistical, Nonlinear, and Soft Matter Physics
Macroscopic friction can emerge from microscopic fluctuations whose mean vanishes but whose autocorrelation does not. Here we use this statistical-mechanical route to resolve a sixty-year-old problem in ocean wave physics, how non-breaking surface waves lose energy to upper-ocean turbulence. The Navier-Stokes equations contain a stochastic vortex force (the coupling between wave orbital motion [...]
Non-peer reviewed Report submitted to Seismica: Correlation of DAS Strain Data and Oceanographic Variables in the North-East Atlantic
Published: 2026-03-17
Subjects: Geophysics and Seismology, Oceanography
DAS recordings close to the coast are influenced by pressure signals from land- and seaward ocean surface gravity waves. The amplitude and period of the signal can serve as proxies for the sea state. Measurements along the cable at greater water depths show secondary microseisms related to the sea state away from the shore. The significant wave height (SWH) and ocean currents along the cable can [...]
Assessing the medium-term risk to reef damage and rubble generation for the Great Barrier Reef
Published: 2026-03-06
Subjects: Atmospheric Sciences, Environmental Monitoring, Life Sciences, Marine Biology, Natural Resources and Conservation, Oceanography, Other Earth Sciences, Physical Sciences and Mathematics
Coral reef systems live in multi-hazard environments and are exposed to a wide range of disturbance events that operate at different spatial and temporal scales. We identify seven drivers derived from hazards that have and can result in reef damage in the Great Barrier Reef (GBR): waves, winds, bottom current velocity, coral bleaching, crown-of-thorns seastar outbreaks, ship groundings, and [...]
Basal Melt Dominance in Grounding-Line Dynamics: SAR Interferometry Reveals How Ocean Thermal Forcing Outpaces Tidal and Seasonal Controls in Antarctic Ice Shelves
Published: 2026-02-18
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The grounding line hinge position for the Fimbul Ice Shelf (Antarctic Peninsula) was determined using Synthetic Aperture Radar (SAR) Interferometric data from June 2023 through October 2024. The data were used to determine the hinge position over eight different time intervals (i.e., SAR Pairs) at an average spatial resolution of 20 meters. The Fimbul Ice Shelf area of interest (AOI) was defined [...]
Resonant Platform Response and Vertical Velocity Biases in ADCP Measurements from Quasi-Lagrangian Platforms
Published: 2026-02-13
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Autonomous surface and subsurface platforms equipped with acoustic Doppler current profilers (ADCPs) are increasingly used to observe ocean velocities, but in the presence of surface waves these measurements can be biased by orbital motion and wave-induced platform tilting. Previous work quantified such biases for idealized platform responses that were in phase with the wave forcing. Here we [...]
Compound Drivers of Antarctic Sea Ice Loss
Published: 2026-02-10
Subjects: Oceanography
Antarctic sea-ice extent began declining since 2015, reaching its lowest extent in the post-1970s observational era in 2023. To diagnose the drivers of this decline, we analyse an observationally constrained sea ice-ocean model spanning 2013-2023, and identify three distinct phases of sea-ice retreat. First, an intensification of westerly winds preconditioned the Southern Ocean via increased [...]
Hybrid Physics–AI Ecosystem Simulations Improve Biogeochemical Predictions in Temperate Shelf Seas
Published: 2026-02-03
Subjects: Artificial Intelligence and Robotics, Biochemistry, Biogeochemistry, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Marine Biology, Numerical Analysis and Scientific Computing, Oceanography, Planetary Biogeochemistry, Terrestrial and Aquatic Ecology
Biogeochemical models form a core part of marine forecasting and climate projections, yet they suffer from persistent biases in predicting key ecosystem variables, creating challenges across regional and global scales. To address this, we developed an AI-augmented three-dimensional hybrid framework that integrates machine-learning corrections directly into a process-based model’s productivity [...]
Compounding effects of hurricanes and marine heat waves in the Gulf of America
Published: 2026-01-29
Subjects: Oceanography
Exposure to extreme events is a primary concern for coastal regions where growing populations and stressed ecosystems are increasingly vulnerable. This study assesses the compounding effects of hurricanes and marine heatwaves (MHWs) in the Gulf of America. Using data from 1982 to 2024, we quantify MHWs through metrics of intensity, frequency, duration, and spatial extent, and examine their [...]
A Quality-Control Procedure for Bio-Optical Applications of Hyperspectral Radiometric Upwelling Radiance and Downwelling Irradiance Profiles Measured by BioGeoChemical-Argo Floats.
Published: 2026-01-27
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology
Autonomous in-situ radiometric observations are increasingly used to constrain bio-optical processes and validate satellite ocean-color products, such as remote sensing reflectance and diffuse attenuation coefficients. Because these observations are collected independently of weather and sea-state conditions, their application critically depends on robust quality control. Starting in 2012, the [...]