In this paper, we use a high-resolution regional ocean model to downscale seasonal ocean forecasts from the Seamless System for Prediction and EArth System Research (SPEAR) model of the Geophysical Fluid Dynamics Laboratory (GFDL). We find that the downscaled model has significantly higher prediction skill in many cases.

We use simulations of our ocean forecasting system to compare the impact of additional altimeter observations from two proposed future satellite constellations. We found that, in our system, an altimeter constellation of 12 nadir altimeters produces improved predictions of sea surface height, surface currents, temperature, and salinity compared to a constellation of 2 wide-swath altimeters.

Transient Attracting Profiles (TRAPs) indicate the most attracting regions of the flow and have the potential to facilitate offshore cleanups in the Great Pacific Garbage Patch. We study the characteristics of TRAPs and the prospects for predicting debris transport from a mesoscale-permitting dataset. Our findings show the relevance of TRAP lifetime estimations to an operational application, and our TRAP tracking algorithm may even benefit other challenges that are related to search at sea.

Recent studies have highlighted the potential vulnerability of the East Antarctic Ice Sheet to atmospheric and oceanic changes. We present new insights from observations from three oceanic moorings below Fimbulisen Ice Shelf from 2009 to 2023. We find that relatively warm water masses reach below the ice shelf both close to the surface and at depth with implications for the basal melting of Fimbulisen.

Most satellite observations have gaps, for example, due to clouds. This paper presents a method to reconstruct missing data in satellite observations of the chlorophyll a concentration in the Black Sea. Rather than giving a single possible reconstructed field, the discussed method provides an ensemble of possible reconstructions using a generative neural network. The resulting ensemble is validated using techniques from numerical weather prediction and ocean modelling.

We focus on understanding the impact of river runoff and precipitation on sea surface salinity (SSS) in the eastern North Tropical Atlantic (e-NTA) region off northwestern Africa. By analyzing regional simulations and observational data, we find that river flows significantly influence SSS variability, particularly after the rainy season. Our findings underscore that a main source of uncertainty representing SSS variability in this region is from river runoff estimates.

We employed a gradient-based algorithm to identify the position and intensity of the fronts in a coastal sea using sea surface temperature data, thereby quantifying their variations. Our study provides a comprehensive analysis of these fronts, elucidating their seasonal variability, intra-tidal dynamics, and the influence of winds on the fronts. By capturing the temporal and spatial dynamics of these fronts, our understanding of the complex oceanographic processes within this region is enhanced.

Identifying tide–surge interaction (TSI) is a complex task. We enhance existing statistical methods with a more-robust test that accounts for complex tides. We also develop a semi-empirical model to investigate the influence of one mechanism of TSI, tidal-phase alteration. We apply these techniques to tide-gauge records from Singapore and the east coast of Peninsular Malaysia. We find TSI at all studied locations: tidal-phase alteration can change the timing of large surges.

Here we show the development of high-resolution simulations of storm surge in the northern Adriatic Sea employing different atmospheric forcing data and physical configurations. Traditional metrics favor a simulation forced by a coarser database and employing a less sophisticated setup. Closer examination allows us to identify a baroclinic model forced by a high-resolution dataset as being better able to capture the variability and peak values of the storm surge.

Understanding how waves and currents interact helps us comprehend physical processes occurring in a coastal environment. In the present work, waves and currents were reproduced in the laboratory and flow velocities were measured. Results showed that the superposition of waves induces a cyclic enhancement or suppression of near-bed turbulence, and, depending on current velocity, wave orbital velocity, and bed roughness, waves can alter the current velocity, following highly nonlinear patterns.

We have developed a methodology for the bias correction of simulated river runoff to force ocean models in which low, medium, and high discharges are corrected once separated at the coast. We show that the bias correction generally leads to an improved representation of river runoff in Europe. The methodology is suitable for model regions with a sufficiently high coverage of discharge observations, and it can be applied to river runoff based on climate hindcasts or climate change simulations.

As Earth’s climate warms, cyclone intensity and rain may increase. Cyclones, like hurricanes, gain strength from warm ocean waters. Understanding how oceans react to strong winds is vital. We highlight ocean responses to pre-storm salinity. Changes in salinity affect oceans during storms: salinity rises, temperature falls, and density increases. We suggest that mixing of near-surface with deeper water may impact heat exchange between the ocean and atmosphere during and after a weather event.

We present an observational study investigating total alkalinity (TA) in the Dutch Wadden Sea. Discrete water samples were used to identify the TA spatial distribution patterns and locate and shed light on TA sources. By observing a tidal cycle, the sediments and pore water exchange were identified as local TA sources. We assumed metabolically driven CaCO₃ dissolution as the TA source in the upper, oxic sediments and anaerobic metabolic processes as TA sources in the deeper, anoxic ones. 

Here, we describe several sea trials with the newly developed CO₂ Seaglider in the Gulf of Alaska. Data evaluation with discrete water and underway samples suggests nearly "weather-quality" CO₂ data as defined by the Global Ocean Acidification Network.

Around 90 % global warming occurs in the ocean but is insufficiently understood at the air–sea interface. Thermodynamics of the standard TEOS-10 is an improved tool for the description of heat exchange processes.

The ocean takes up carbon dioxide (CO₂) from the atmosphere, slowing climate change. This CO₂ uptake is controlled by a property called ƒCO₂. Seawater ƒCO₂ changes as seawater warms or cools, although by an uncertain amount; measurements and calculations give inconsistent results. Here, we work out how ƒCO₂ should, in theory, respond to temperature. This matches field data and model calculations but still has discrepancies with scarce laboratory results, which need more measurements to resolve.

This study examines how the ocean's chaotic variability and atmospheric fluctuations affect yearly changes in North Atlantic Subtropical Mode Water (STMW) properties, using an ensemble of realistic ocean simulations. Results show that while yearly changes in STMW properties are mostly paced by the atmosphere, a notable part of these changes are random in phase. This study also illustrates the value of ensemble simulations over single runs in understanding oceanic fluctuations and their causes.

An AI model was used to fill in missing parts of sea temperature (SST) maps caused by cloud cover. We found masked autoencoders can recreate missing SSTs with less than 0.2 °C error, even when 80 % are missing. This is 5000 times faster than conventional methods tested on a single central processing unit. This can enhance our ability in monitoring global small-scale ocean fronts that affect heat, carbon, and nutrient exchange in the ocean. The method is promising for future research.

Eastern boundary upwelling systems (EBUSs) are crucial for resources, but climate change poses uncertainties for their future. To assess global warming's impact, we examine Andrew Bakun's 1990 hypothesis of intensified upwelling using deseasonalized sea surface temperature data. A new index, α_UI, normalizes upwelling trends against non-upwelling processes, confirming intensification in all EBUSs and supporting Bakun's hypothesis.

The latitudinally alternating zonal jets are a ubiquitous feature of the ocean. We use a simple model to illustrate the potential role of these jets in the formation, maintenance, and multidecadal variability in the oxygen minimum zones, using the eastern tropical North Atlantic oxygen minimum zone as an example.

In the Weddell Sea, we investigated how warm deep currents and cold waters containing freshwater released from the Antarctic are connected. We used autonomous observation devices that have never been used in this region previously and that allow us to track the movement and characteristics of water masses under the sea ice. Our findings show a dynamic interaction between warm masses, providing key insights to understand climate-related changes in the region.

We studied the increasing or decreasing of chlorophyll a abundance in the German Bight. Chlorophyll a is the pigment present in algae that allows them to capture energy from the sun and indicates both the growth of the algae and the health of the environment. Most of the German Bight has decreasing chlorophyll a concentration in the analysed period. In addition, about 45 % of the changes happening in chlorophyll a were connected with changes in temperature.