[1] Oxygen isotopic records of meltwater outflow and records of sea level change do not support the idea that fresh waters derived solely from the melting of Northern Hemisphere ice sheets was likely to have stabilized the upper layers of the North Atlantic Ocean and prevented deep convection during the Younger Dryas. Yet there are paleoceanographic indicators that point to a pause in the forma...

The adiabatic transit time of wave energy radiated by an Agulhas ring released in the South Atlantic Ocean to the North Atlantic Ocean is investigated in a two-layer ocean model. Of particular interest is the arrival time of baroclinic energy in the northern part of the Atlantic, because it is related to variations in the meridional overturning circulation. The influence of the Mid-Atlantic Rid...

Since the open-ocean subpolar Atlantic is amongst the most predictable regions in the world, our results hold promise for predicting the general production to seabird populations over a large geographical region adjacent to the northern North Atlantic and the Arctic Mediterranean. Colonies of black-legged kittiwakes Rissa tridactyla in the North Atlantic have declined markedly since the mid-199...

The Atlantic Multidecadal Oscillation (AMO) represents a significant driver of Northern Hemisphere climate, but the forcing mechanisms pacing the AMO remain poorly understood. Here we use the available proxy records to investigate the influence of solar and volcanic forcing on the AMO over the last ~450 years. The evidence suggests that external forcing played a dominant role in pacing the AMO ...

This thesis addresses several aspects of the problem of determining the effect of the low-frequency eddy variability on the mean circulation of the Western North Atlantic. A framework for this study is first established by scale analysis of the eddy and mean terms in the mean momentum, vorticity, and heat balances in three regions of the Western North Atlantic -the northern recirculation, the s...

[1] Between 20 and 80 kyr ago several cooling cycles occurred in the Northern Hemisphere which culminated in a discharge of icebergs into the North Atlantic. These so called ‘‘Heinrich Events’’ (HEs) were followed by an abrupt shift to a warmer climate. Here we use a coupled ocean-atmosphere-sea ice model to study the response of the climate system under glacial conditions to a hypothetical HE....

The internal and external North Atlantic Sector variability is investigated by means of a multimillennial control run and forced experiments with the Kiel Climate Model (KCM). The internal variability is studied by analyzing the control run. The externally forced variability is investigated in a run with periodic millennial solar forcing and in greenhouse warming experiments with enhanced carbo...

The Baltic Sea has traditionally been considered as a semi-enclosed marginal sea with little or no inß uence on the adjacent oceans. We employ an eddy-permitting, coupled ice-ocean model of the Pan-Arctic region to study the Baltic Sea, especially its circulation and property exchanges with the North Sea and other regions. Using this high-resolution and large scale model we focus here on the fr...

Based on specimens collected during the sampling campaigns in the Northern Adriatic from 2003-2010, the diversity of genus Terebellides (Polychaeta; Trichobranchidae) was studied and three species are reported for the Northern Adriatic Sea: Terebellides gracilis Malm, 1874, Terebellides mediterranea spec. nov., and Terebellides stroemii Sars, 1835. Terebellides stroemii was the only species pre...

Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic warming. However, variability in ultraviolet solar irradiance is linked to modulation of the Arctic and North Atlantic Oscillations, suggesting the potential for larger regional surface climate effects. Here, we explore possible impacts thro...