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The extent to which siblings resemble each other measures the total impact of family backgroundin shaping life outcomes. We study sibling similarity in cognitive skills, school grades, andeducational attainment in Finland, Germany, Norway, Sweden, the United Kingdom, and theUnited States. We also compare sibling similarity by parental education and occupation withinthese societies. The comparison of sibling correlations across and within societies allows us tocharacterize the omnibus impact of family background on education across social landscapes. Wefind similar levels of sibling similarity across social groups. Across countries, we find only smalldifferences. In addition, rankings of countries in sibling resemblance differ across the threeeducational outcomes we study. We conclude that sibling similarity is largely similar acrossadvanced, industrialized countries and across social groups within societies contrary to theoriesthat suggest large cross-national differences and variation of educational mobility across socialgroups within societies.

Coastal evolution occurs on a wide range of time-scales, from storms, seasonal and inter-annual time-scales to longer-term adaptation to changing environmental conditions. Measuring campaigns typically either measure morphological evolution on a short-time scale (days) with high frequency (hourly) or long-time scales (years) but intermittently (monthly). This leaves an important observational gap that limits morphological variability assessments. Traditional echo sounding measurements on this long time-scale and high-frequency sampling require a significant financial injection. Shore-based video systems with high spatiotemporal resolution can bridge this gap. For the first time, hourly Kalman filtered video-derived bathymetries covering 1.5 years of morphological evolution with an hourly resolution obtained at Porhtowan, UK are presented. Here, the long-term hourly dataset is used and aims to show its added value for, and provide an in-depth, morphological analyses with unprecedented temporal resolution. The time-frame includes calm and extreme (storm) wave conditions in a macro-tidal environment. The video-derived bathymetries allow hourly beach state classification while before this was not possible due to the dependence on foam patterns of wave breaking (e.g., saturation during storms). The study period covers extreme storm erosion during the most energetic winter season in 60 years (2013-2014). Recovery of the beach takes place on several time-scales: (1) an immediate initial recovery after the storm season (first 2 months), (2) limited recovery during low energetic summer conditions and (3) accelerated recovery as the wave conditions picked up in the subsequent fallunder wave conditions that are typically erosive. The video-derived bathymetries are shown to be effective in determining bar-positions, outer-bar three-dimensionality and volume analyses with an unprecedented hourly temporal resolution.

Despite the increased sophistication of numerical models and field techniques for investigating wave-induced nearshore sediment transport and ensuing beach morphological response, there remains a significant demand for large-scale laboratory experiments to address this research topic. Here, we describe the Barrier Dynamics II Experiment (BARDEX II), which involved placing a near prototype-scale sandy barrier in the middle of the Delta Flume in the Netherlands and subjecting the structure to a range of wave, tide, and water level conditions. A unique aspect of the experiment was the presence of a lagoon behind the barrier, as often occurs in natural barrier settings, providing a convenient means to experimentally manipulate the groundwater hydrology within the barrier. The overall aim of the BARDEX II was to collect a large-scale data set of energetic waves acting on a sandy beach/barrier system to improve our quantitative understanding and modeling capability of shallow water sediment transport processes in the inner surf, swash, and overwash zone. In this paper, we introduce BARDEX II and provide a detailed description of the experiment, including the experimental design, instrumentation, test program, and data set, as well as presenting some examples of the morphological and hydrodynamic data set. We also reflect objectively on the strengths and weaknesses of the data set. This paper serves as an introduction to a special issue of Coastal Engineering, solely devoted to the results of BARDEX II. (C) 2015 Elsevier B.V. All rights reserved.

Expanding hypoxia in the Baltic Sea over the past century has led to the development of anoxic and sulfidic (euxinic) deep basins that are only periodically ventilated by inflows of oxygenated waters from the North Sea. In this study, we investigate the potential consequences of the expanding hypoxia for manganese (Mn) burial in the Baltic Sea using a combination of pore water and sediment analyses of dated sediment cores from eight locations. Diffusive fluxes of dissolved Mn from sediments to overlying waters at oxic, hypoxic and euxinic sites are consistent with an active release of Mn from these areas. Although the present-day fluxes are significant (ranging up to ca. 240 μmol m−2 d−1), comparison to published water column data suggests that the current benthic release of Mn is small when compared to the large pool of Mn already present in the hypoxic and anoxic water column. Our results highlight two modes of Mn carbonate formation in sediments of the deep basins. In the Gotland Deep area, Mn carbonates likely form from Mn oxides that are precipitated from the water column directly following North Sea inflows. In the Landsort Deep, in contrast, Mn carbonate and Mn sulfide layers appear to form independently of inflow events, and are possibly related to the much larger and continuous input of Mn oxides linked to sediment focusing. Whereas Mn-enriched sediments continue to accumulate in the Landsort Deep, this does not hold for the Gotland Deep area. Here, a recent increase in euxinia, as evident from measured bottom water sulfide concentrations and elevated sediment molybdenum (Mo), coincides with a decline in sediment Mn content. Sediment analyses also reveal that recent inflows of oxygenated water (since ca. 1995) are no longer consistently recorded as Mn carbonate layers. Our data suggest that eutrophication has not only led to a recent rise in sulfate reduction rates but also to a decline in reactive Fe input to these basins. We hypothesize that these factors have jointly led to higher sulfide availability near the sediment–water interface after inflow events. As a consequence, the Mn oxides may be reductively dissolved more rapidly than in the past and Mn carbonates may no longer form. Using a simple diagenetic model for Mn dynamics in the surface sediment, we demonstrate that an enhancement of the rate of reduction of Mn oxides is consistent with such a scenario. Our results have important implications for the use of Mn carbonate enrichments as a redox proxy in marine systems.