Preprints
Filtering by Subject: Oceanography
Different mechanisms of Arctic first-year sea-ice ridge consolidation observed during the MOSAiC expedition
Published: 2023-05-10
Subjects: Earth Sciences, Glaciology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Sea-ice ridges constitute a large fraction of the ice volume in the Arctic Ocean, yet we know little about the evolution of these ice masses. Here we examine the thermal and morphological evolution of an Arctic first-year sea-ice ridge, from its formation to advanced melt. Initially the mean keel depth was 5.6 m and mean sail height was 0.7 m. The initial rubble macroporosity (fraction of [...]
A cost model for ocean iron fertilization as a means of carbon dioxide removal that compares ship- and aerial-based delivery, and estimates verification costs.
Published: 2023-04-14
Subjects: Oceanography
This paper presents a cost model for implementing a deployment scale effort for conducting ocean iron fertilization (OIF) for marine-based carbon dioxide removal (CDR). The model incorporates basic oceanographic parameters critical for estimating the effective export of newly fixed CO2 into biomass that is stimulated by Fe addition to an Fe-limited region of the Southern Ocean. Estimated costs [...]
Efficient modeling of wave generation and propagation in a semi-enclosed estuary
Published: 2023-03-14
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Accurate, and high-resolution wave statistics are critical for regional hazard mapping and planning. However, long-term simulations at high spatial resolution are often computationally prohibitive. Here, multiple rapid frameworks including fetch-limited, look-up-table (LUT), and linear propagation are combined and tested in a large estuary exposed to both remotely (swell) and locally generated [...]
Relative contributions of water level components to extreme water levels along the United States Southeast Atlantic Coast from a regional-scale water level hindcast
Published: 2023-03-13
Subjects: Oceanography
A 38-year hindcast water level product is developed for the United States Southeast Atlantic coastline from the entrance of Chesapeake Bay to the southeast tip of Florida. The water level modelling framework utilized in this study combines a global-scale hydrodynamic model (Global Tide and Surge Model, GTSM-ERA5), a novel ensemble-based tide model, a parameterized wave setup model, and [...]
A new, global optical sediment trap calibration
Published: 2023-02-25
Subjects: Oceanography
Autonomous sensors for gravitational carbon flux in the ocean are critically needed, because of uncertainties in the projected response of the biological carbon pump (BCP) to climate change, and the proposed, engineered acceleration of the BCP to sequester carbon dioxide in the ocean. Optical sediment trap (OST) sensors directly sense fluxes of sinking particles in a manner that is independent [...]
An Updated Parametrization of Algorithms to Retrieve the Diffuse Attenuation of Light in the Ocean from Remote Sensing and its Impact on Estimates of Net Primary Productivity
Published: 2023-02-10
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Environmental Sciences
We recently found a significant bias while validating frequently used ocean color algorithms retrieving the spectral diffuse attenuation coefficient (Kd(λ))(Begouen and Boss, 2022). Here we modify existing algorithms for Kd(λ) to remove the observed bias at Kd(490), and evaluate the impact on global and regional estimates of net primary production (NPP) using two different primary production [...]
Sand Shoal Dynamics of a Tide-Dominated Estuarine Embayment: Comparison of a Numerical Sediment Transport Model against Field Observations
Published: 2023-02-07
Subjects: Engineering, Environmental Engineering, Oceanography
This paper presents an innovative and detailed dataset of currents and sediment transport observations over a sand shoal system responsible for focusing wave energy on eroding coastline. The data are used to measure the performance of a detailed numerical sediment transport model of the sand shoal system. The predictive skill of the model is 0.96 for tidal elevations within Port Phillip Bay, 0.75 [...]
Internal gravity waves generated by subglacial discharge: implications for tidewater glacier melt
Published: 2023-02-03
Subjects: Climate, Oceanography
Submarine melting has been implicated in the accelerated retreat of marine-terminating glaciers globally. Energetic ocean flows, such as subglacial discharge plumes, are known to enhance submarine melting in their immediate vicinity. Using observations and a large eddy simulation, we demonstrate that discharge plumes emit high-frequency internal gravity waves that propagate along glacier termini [...]
How fine is fine enough? Effect of mesh resolution on hydrodynamic simulations in coral reef environments
Published: 2023-01-14
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Coral reef environments are biodiversity hotspots that provide many services to coastal communities. They are currently facing an increasing anthropogenic pressure that jeopardises their survival. Numerical ocean models are an important tool to understand the functioning of coral ecosystems and the mechanisms ensuring their resilience. However, simulating the water circulation through reef [...]
Improving Shoreline Forecasting Models with Multi-Objective Genetic Programming
Published: 2023-01-11
Subjects: Artificial Intelligence and Robotics, Climate, Environmental Engineering, Environmental Monitoring, Geomorphology, Hydrology, Numerical Analysis and Scientific Computing, Oceanography, Sedimentology, Statistical Models
Given the current context of climate change and increasing population densities at coastal zones, there is an increasing need to be able to predict the development of our coasts. Recent advances in artificial intelligence allow for automatic analysis of observational data. This work makes use of Symbolic Regression, a type of Machine Learning algorithm, to evolve interpretable shoreline [...]
Weakening of the Indian Ocean Dipole in the mid-Holocene due to the mean oceanic climatology change
Published: 2023-01-11
Subjects: Atmospheric Sciences, Climate, Meteorology, Oceanography
The Indian Ocean Dipole (IOD) is one of the leading modes of interannual climate variability in the tropical Indian Ocean (IO). Paleoclimate provides real climate scenarios to examine IOD behaviors and the linkage to basic states. Based on 18 models from the Paleoclimate Modelling Intercomparison Project phase 3 and 4 (PMIP 3/4), the IOD change from the preindustrial period to mid-Holocene is [...]
Historical & future maximum ocean temperatures
Published: 2022-12-16
Subjects: Oceanography
Marine heatwaves impact ocean ecosystems and are expected to become more frequent and intense with continued global warming. The ability of Earth system models to reproduce the statistical characteristics of extreme ocean temperatures has not yet been tested quantitatively, making the reliability of their future projections of marine heatwaves uncertain. We demonstrate that annual maxima of [...]
Extracting information from ocean color
Published: 2022-12-09
Subjects: Oceanography, Other Oceanography and Atmospheric Sciences and Meteorology
Products derived from remote sensing reflectances ($R_{rs}(\lambda)$), e.g. chlorophyll, phytoplankton carbon, euphotic depth, or particle size, are widely used in oceanography. Problematically, $R_{rs}(\lambda)$ may have fewer degrees of freedom (DoF) than measured wavebands or derived products. A global sea surface hyperspectral $R_{rs}(\lambda)$ dataset has DoF=4. MODIS-like multispectral [...]
Global climate change trends detected in indicators of ocean ecology
Published: 2022-12-07
Subjects: Oceanography
Climate change-driven trends in phytoplankton populations, as viewed by Earth-observing satellites, were thought to be masked by strong natural variability, so that >30 years of continuous data was needed to detect a climate trend. Here we show that climate change trends emerge more rapidly in ocean color (remote sensing reflectance, Rrs), as Rrs is multivariate and some wavebands have low [...]
Atmospheric carbon emissions from benthic trawling depend on water depth and ocean circulation
Published: 2022-10-28
Subjects: Biogeochemistry, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology
Through its vastness, resilience and biogeochemical complexity, the ocean offers humanity some of the largest potential natural pathways for removing carbon dioxide from the atmosphere while avoiding new sources of anthropogenic emissions. In proposing a network of new marine protected areas in service of global ocean conservation, Sala et al. describe a potentially large climate benefit of such [...]