The RAPID 26° N array has been measuring the Atlantic Meridional Overturning Circulation (AMOC) since 2004. Since 2009 the AMOC has, compared with previous years, been in a low state. In 2013–2015 in the northern North Atlantic, strong cooling was observed in the ocean and anticipated to intensify the strength of the AMOC some years later. Here, we analyse the latest results from 26° N and conclude that while the AMOC is increasing since 2009, this increase is not statistically significant.

An analytical method combining electro-dialysis with high performance anionic exchange chromatography coupled to pulsed amperometric detection was developed and optimized for analysing free and combined monosaccharides in seawater and other saline environmental samples.

The role of oceans in the global mercury cycle is poorly understood. Investigation of sediments revealed that biological productivity and scavenging of water phase mercury by sinking algae or algae derived organic matter controlled preindustrial mercury accumulation in Adélie Basin. Our study suggests that the periodic-like variations in Hg concentrations and accumulation rates are likely associated with the cycle of polynya opening and closing and its related changes in biological productivity.

The input of mechanical power to the ocean due to the surface wind-stress is considered using data from satellites observations. Its dependence on the coarse-graining scale of the atmospheric and oceanic velocity in space and time is determined. The power input is found to increase monotonically with shorter coarse-graining in time. Results show that including the dynamics at scales below a few degrees reduces considerably the power input by air-sea interaction.

On ice affected coasts obtaining yearlong sea level records for traditional tidal predictions is difficult. We evaluate the Complete Tidal Species Modulation with Tidal Constant Corrections (CTSM+TCC) method for predicting tides at the 'mixed, mainly diurnal' Jang Bogo Antarctic Research Station in the Ross Sea, Antarctica, using short in situ records plus longer records from the nearby 'diurnal' Cape Roberts. The method proved successful using data from periods with above average tidal ranges.

We investigated the impact of indicator dye impurities on spectrophotometric seawater measurements, especially how they may influence the drift behavior and the measurement quality of an autonomous analyzer using this indicator. These measurements are important for ocean carbon observations. This work revealed that impurities up to a quantity of 2 % do not influence the measurement drift and quality. Higher impurity levels lead to a changing drift behavior and quality deteriorations.

This project is part of the graduate school Baltic Transcoast. This graduate school aimed to investigate the interaction between a coastal fen and the Baltic sea. In this work, the mixing and transport of the submarine groundwater discharge (SGD) was investigated in a defined laboratory experiment. For this, a new wave channel ground model was constructed and produced to facilitate the variation of different parameters for the investigations.

The Yenisei and Khatanga rivers are among the largest estuarine rivers that inflow to the Arctic Ocean. Discharge of the Yenisei River is one order of magnitude larger than of the Khatanga River. However, spatial scales of buoyant plumes formed by freshwater runoffs from the Yenisei and Khatanga gulfs are similar. This feature is caused by intense tidal mixing in the Khatanga Gulf, which causes formation of diluted and, therefore, anomalously deep and large Khatanga plume.

Common ways of describing the rise and fall of the tides are essential for safe and productive coastal habitation. We have long had a useful formula to describe the rise and fall of tides at daily timescales but no purposive method for characterizing tidal height variations at longer timescales. This paper uses observations from New Zealand, plus model and theory data, to explain different tide envelop types at monthly timescales, complementing the existing way of describing daily tidal forms.

The dynamics of the European Northwest Shelf and the surrounding deep ocean are analysed using both classical Eulerian and Lagrangian data from simulated particles. Focussing on the latter, a quantity named density trend measures particle accumulation. Yearly averages reveal no surface accumulation areas in the deep ocean and elongated patterns on the shelf mainly along fronts. Sensitivity experiments show the influence of tides and wind unveiling important vertical dynamics in coastal areas.

River plume characteristics (density, velocity, turbulence) are measured in the first several kilometers of a river flow entering Doubtful Sound, New Zealand. These observations are used to examine the momentum of the plume and determine the influence of the main dynamics on controlling the behavior and structure of the plume. The consideration of internal hydraulics and wave radiation is necessary to understand fully the impact of governing dynamics on plume behavior and evolution.