Preprints
Filtering by Subject: Oceanography
Potential effects of coagulation processes on phytoplankton mortality in the Elbe estuary from a Lagrangian point of view
Published: 2024-10-17
Subjects: Biogeochemistry, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Oceanography, Water Resource Management
Within the Elbe estuary, a sudden change in depth occurs when the river enters the shipping channel in the Port of Hamburg. This change in depth correlates with a sharp decline in phytoplankton concentrations. This decline affects the estuarine food web and shifts the ecosystem from autotrophic to heterotrophic during the summer months. Previous studies have hypothesized that this collapse is [...]
Questioning Dark Oxygen Production in the Deep-sea Ferromanganese Nodule Field
Published: 2024-10-04
Subjects: Earth Sciences, Geochemistry, Geology, Oceanography
Previous studies have concluded that the natural process where oxygen is consumed as decomposition of organic matter that supplied from shallow waters occurs on the deep-sea floor. Sweetman et al.1 presented the surprising observation that deep-sea ferromanganese nodules generate oxygen, which they labelled as dark oxygen production. The authors claimed that oxygen was generated through the [...]
Carbon storage in Northern Ireland’s aquatic ecosystems: an evidence synthesis to support policy development.
Published: 2024-09-06
Subjects: Biogeochemistry, Marine Biology, Oceanography
Blue carbon is defined as carbon that is naturally sequestered and stored in the world’s aquatic ecosystems. Governments around the world are currently seeking to develop a range of tools to help meet their commitments to reduce greenhouse gas emissions and potentially reverse anthropogenic climate change. As such, there is growing interest from policy makers in natural processes which may be [...]
Two-dimensional Ekman-Inertial Instability: A comparison with Inertial Instability
Published: 2024-08-29
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
In the ocean, submesoscale flows tend to undergo several hydrodynamic instabilities. In particular, Inertial Instability (InI) and Ekman-Inertial Instability (EII) are known to develop in geostrophically balanced barotropic flows whose lateral shear is larger in magnitude and opposite in sign to the Coriolis parameter. Although these instabilities share some elements, their dynamical nature can [...]
The turbulent dynamics of anticyclonic submesoscale headland wakes
Published: 2024-08-10
Subjects: Oceanography
Flow interacting with bathymetry has been posited to be important for dissipation and mixing in the global ocean. Despite this, there are large uncertainties regarding mixing in these environments, particularly as it pertains to the role of submesoscale structures in the dynamics and energetics. In this work we study such flows with a series of Large-Eddy simulations of a submesoscale flow past a [...]
The Overlooked Sub-Grid Air-Sea Flux in Climate Models
Published: 2024-05-18
Subjects: Atmospheric Sciences, Climate, Numerical Analysis and Scientific Computing, Oceanography
Understanding air-sea interaction is crucial for our ability to predict future states of the climate system, and to inform economic and societal decision-making. However, the representation of air-sea interactions in climate models is limited by structural errors associated with model resolution. Coarse-resolution climate models do not resolve small-scale structures in the air-sea state, which, [...]
Unique In-situ Measurements from Greenland Fjord Show Winter Freshening by Subglacial Melt
Published: 2024-05-08
Subjects: Earth Sciences, Glaciology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics
The interaction between glacier fronts and ocean waters is one of the key uncertainties for projecting future ice mass loss. Direct observations at glacier fronts are sparse but studies indicate that the magnitude and timing of freshwater fluxes are crucial in determining fjord circulation, ice frontal melt and ecosystem habitability. Particularly wintertime dynamics are severely understudied due [...]
SWOT Data Assimilation with Correlated Error Reduction: Fitting Model and Error Together
Published: 2024-05-01
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The Surface Water Ocean Topography (SWOT) satellite mission provides high-resolution two-dimensional sea surface height (SSH) data with swath coverage. However, spatially correlated errors affect these SSH measurements, particularly in the cross-track direction. The scales of errors can be similar to the scales of ocean features. Conventionally, instrumental errors and ocean signals have been [...]
Numerical simulation of the 2D trajectory of a non-buoyant fluid parcel under the influence of inertial oscillation
Published: 2024-04-24
Subjects: Atmospheric Sciences, Fluid Dynamics, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Oceanography
The trajectory of non-buoyant fluid parcels under the influence of inertial oscillations is a pivotal phenomenon in geophysical fluid dynamics, impacting processes such as tracer transport, pollutant dispersion, and the dynamics of marine organisms. This study presents a comprehensive numerical investigation of the two-dimensional trajectory of a non-buoyant fluid parcel subjected to inertial [...]
Dynamics of Aggregates and Sinking Carbon Fluxes in a Turbulent Ocean
Published: 2024-04-23
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The ocean's biological pump, a critical component of the Earth's carbon cycle, transports organic matter from the surface ocean to depth, which is dominated by the sinking particles, often in the form of large (>1 mm) marine snow aggregates. Controls on carbon export are thought to be driven solely by ecological processes that produce and repackage sinking particles. Here, we present [...]
Seasonality of spectral radiative fluxes and optical properties of Arctic sea ice during the spring-summer transition
Published: 2024-02-16
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology
The reflection, absorption, and transmittance of solar (shortwave) radiation by sea ice play a crucial role in physical and biological processes in the ice-covered Arctic Ocean and atmosphere. These sea ice optical properties are of great importance, in particular during the melt season, as they significantly impact energy fluxes within and the total energy budget of the coupled [...]
Year-long benthic measurements of environmental conditions indicate high sponge biomass is related to strong bottom currents over the Northern Labrador shelf
Published: 2024-01-22
Subjects: Marine Biology, Oceanography, Other Oceanography and Atmospheric Sciences and Meteorology
Deep-sea sponge grounds are distributed globally and are considered hotspots of biological diversity and biogeochemical cycling. To date, little is known about the environmental constraints that control where deep-sea sponge grounds occur and what conditions allow high sponge biomass to develop in the deep sea. Here, we characterize oceanographic conditions at two contrasting high- and [...]
Role of Indonesian Archipelago on Global Thermohaline Circulation: Insights from Numerical Experiments
Published: 2023-12-19
Subjects: Numerical Analysis and Scientific Computing, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This study employs the cGENIE Earth System Model to investigate the effects of the Indonesian Throughflow (ITF) and Indonesian Archipelago (IA) closure on global meridional thermohaline circulation (THC). Over a simulated period of 10,000 years, the analysis centers on critical variables, including surface density, vertical density profiles, global overturning circulation, and ocean ventilation [...]
Overview of the MOSAiC expedition: Ecosystem
Published: 2023-12-08
Subjects: Marine Biology, Oceanography
An international and interdisciplinary sea ice drift expedition, the ‘The Multidisciplinary drifting Observatory for the Study of Arctic Climate‘ (MOSAiC), was conducted from October 2019 to September 2020. The aim of MOSAiC was to study the interconnected physical, chemical and biological characteristics and processes from the atmosphere to the deep sea of the central Arctic system. The [...]
A study of extreme water waves using a hierarchy of models based on potential-flow theory
Published: 2023-12-02
Subjects: Applied Mathematics, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Partial Differential Equations, Physical Sciences and Mathematics
The formation of extreme waves arising from the interaction of three line-solitons with equal far-field amplitudes is examined through a hierarchy of water-wave models. The Kadomtsev-Petviashvili equation (KPE) is first used to prove analytically that its exact three-soliton solution has a ninefold maximum amplification that is achieved in the absence of spatial divergence. Reproducing this [...]