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Ocean ecosystems are increasingly stressed by human-induced changes of their physical, chemical and biological environment. Among these changes, warming, acidification, deoxygenation and changes in primary productivity by marine phytoplankton can be considered as four of the major stressors of open ocean ecosystems. Due to rising atmospheric CO2 in the coming decades, these changes will be amplified. Here, we use the most recent simulations performed in the framework of the Coupled Model Intercomparison Project 5 to assess how these stressors may evolve over the course of the 21st century. The 10 Earth system models used here project similar trends in ocean warming, acidification, deoxygenation and reduced primary productivity for each of the IPCC's representative concentration pathways (RCPs) over the 21st century. For the \"business-as-usual\" scenario RCP8.5, the model-mean changes in the 2090s (compared to the 1990s) for sea surface temperature, sea surface pH, global O2 content and integrated primary productivity amount to +2.73 (±0.72) °C, −0.33 (±0.003) pH unit, −3.45 (±0.44)% and −8.6 (±7.9)%, respectively. For the high mitigation scenario RCP2.6, corresponding changes are +0.71 (±0.45) °C, −0.07 (±0.001) pH unit, −1.81 (±0.31)% and −2.0 (±4.1)%, respectively, illustrating the effectiveness of extreme mitigation strategies. Although these stressors operate globally, they display distinct regional patterns and thus do not change coincidentally. Large decreases in O2 and in pH are simulated in global ocean intermediate and mode waters, whereas large reductions in primary production are simulated in the tropics and in the North Atlantic. Although temperature and pH projections are robust across models, the same does not hold for projections of subsurface O2 concentrations in the tropics and global and regional changes in net primary productivity. These high uncertainties in projections of primary productivity and subsurface oxygen prompt us to continue inter-model comparisons to understand these model differences, while calling for caution when using the CMIP5 models to force regional impact models.

The MPI‐ESM1.2 is the latest version of the Max Planck Institute Earth System Model and is the baseline for the Coupled Model Intercomparison Project Phase 6 and current seasonal and decadal climate predictions. This paper evaluates a coupled higher‐resolution version (MPI‐ESM1.2‐HR) in comparison with its lower‐resolved version (MPI‐ESM1.2‐LR). We focus on basic oceanic and atmospheric mean states and selected modes of variability, the El Niño/Southern Oscillation and the North Atlantic Oscillation. The increase in atmospheric resolution in MPI‐ESM1.2‐HR reduces the biases of upper‐level zonal wind and atmospheric jet stream position in the northern extratropics. This results in a decrease of the storm track bias over the northern North Atlantic, for both winter and summer season. The blocking frequency over the European region is improved in summer, and North Atlantic Oscillation and related storm track variations improve in winter. Stable Atlantic meridional overturning circulations are found with magnitudes of ~16 Sv for MPI‐ESM1.2‐HR and ~20 Sv for MPI‐ESM1.2‐LR at 26°N. A strong sea surface temperature bias of ~5°C along with a too zonal North Atlantic current is present in both versions. The sea surface temperature bias in the eastern tropical Atlantic is reduced by ~1°C due to higher‐resolved orography in MPI‐ESM‐HR, and the region of the cold‐tongue bias is reduced in the tropical Pacific. MPI‐ESM1.2‐HR has a well‐balanced radiation budget and its climate sensitivity is explicitly tuned to 3 K. Although the obtained reductions in long‐standing biases are modest, the improvements in atmospheric dynamics make this model well suited for prediction and impact studies. Key Points A higher‐resolution version of MPI‐ESM1.2 is presented, which has a well‐balanced radiation budget and stable ocean circulation The higher atmospheric resolution improves North Atlantic storm tracks, blocking frequency, and NAO representation The higher computational costs remain manageable and enable studies of seasonal to decadal predictions and climate impacts

We present the first global ocean‐biogeochemistry model that uses a telescoping high resolution for an improved representation of coastal carbon dynamics: ICON‐Coast. Based on the unstructured triangular grid topology of the model, we globally apply a grid refinement in the land‐ocean transition zone to better resolve the complex circulation of shallow shelves and marginal seas as well as ocean‐shelf exchange. Moreover, we incorporate tidal currents including bottom drag effects, and extend the parameterizations of the model's biogeochemistry component to account explicitly for key shelf‐specific carbon transformation processes. These comprise sediment resuspension, temperature‐dependent remineralization in the water column and sediment, riverine matter fluxes from land including terrestrial organic carbon, and variable sinking speed of aggregated particulate matter. The combination of regional grid refinement and enhanced process representation enables for the first time a seamless incorporation of the global coastal ocean in model‐based Earth system research. In particular, ICON‐Coast encompasses all coastal areas around the globe within a single, consistent ocean‐biogeochemistry model, thus naturally accounting for two‐way coupling of ocean‐shelf feedback mechanisms at the global scale. The high quality of the model results as well as the efficiency in computational cost and storage requirements proves this strategy a pioneering approach for global high‐resolution modeling. We conclude that ICON‐Coast represents a new tool to deepen our mechanistic understanding of the role of the land‐ocean transition zone in the global carbon cycle, and to narrow related uncertainties in global future projections. Plain Language Summary The coastal ocean is an area hardly taken into account by current climate change assessment activities. Yet, its capacity in carbon dioxide (CO2) uptake and storage is crucial to be included in a science‐based development of sustainable climate change mitigation and adaptation strategies. Earth system models are powerful tools to investigate the marine carbon cycle of the open ocean. The coastal ocean, however, is poorly represented in global models to date, because of missing key processes controlling coastal carbon dynamics and too coarse spatial resolutions to adequately simulate coastal circulation features. Here, we introduce the first global ocean‐biogeochemistry model with a dedicated representation of the coastal ocean and associated marine carbon dynamics: ICON‐Coast. In this model, we globally apply a higher resolution in the coastal ocean and extend the accounted physical and biogeochemical processes. This approach enables for the first time a consistent, seamless incorporation of the global coastal ocean in model‐based Earth system research. In particular, ICON‐Coast represents a new tool to deepen our understanding about the role of the land‐ocean transition zone in the global climate system, and to narrow related uncertainties in possible and plausible climate futures. Key Points We introduce the first global ocean‐biogeochemistry model with a dedicated representation of coastal carbon dynamics We globally apply a grid refinement in the coastal ocean to better resolve regional circulation features, including ocean‐shelf exchange We explicitly incorporate key physical and biogeochemical processes controlling coastal carbon dynamics

The late Paleocene is characterized by warm and stable climatic conditions that served as the background climate for the Paleocene–Eocene Thermal Maximum (PETM, ~55 million years ago). With respect to feedback processes in the carbon cycle, the ocean biogeochemical background state is of major importance for projecting the climatic response to a carbon perturbation related to the PETM. Therefore, we use the Hamburg Ocean Carbon Cycle model (HAMOCC), embedded in the ocean general circulation model of the Max Planck Institute for Meteorology, MPIOM, to constrain the ocean biogeochemistry of the late Paleocene. We focus on the evaluation of modeled spatial and vertical distributions of the ocean carbon cycle parameters in a long-term warm steady-state ocean, based on a 560 ppm CO2 atmosphere. Model results are discussed in the context of available proxy data and simulations of pre-industrial conditions. Our results illustrate that ocean biogeochemistry is shaped by the warm and sluggish ocean state of the late Paleocene. Primary production is slightly reduced in comparison to the present day; it is intensified along the Equator, especially in the Atlantic. This enhances remineralization of organic matter, resulting in strong oxygen minimum zones and CaCO3 dissolution in intermediate waters. We show that an equilibrium CO2 exchange without increasing total alkalinity concentrations above today's values is achieved. However, consistent with the higher atmospheric CO2, the surface ocean pH and the saturation state with respect to CaCO3 are lower than today. Our results indicate that, under such conditions, the surface ocean carbonate chemistry is expected to be more sensitive to a carbon perturbation (i.e., the PETM) due to lower CO32− concentration, whereas the deep ocean calcite sediments would be less vulnerable to dissolution due to the vertically stratified ocean.

We have studied the concentration of vitamins A (retinol) and E (α-tocopherol) in the tissues of the bank vole ( Myodes ( Clethrionomys ) glareolus ) and common shrew ( Sorex araneus ) inhabiting the northern periphery of its natural habitat. The distribution of vitamin A in the common shrew and bank vole tissues is similar: the highest concentration is found in the liver, and the lowest level is found in the heart. Age-related differences in the retinol concentration are detected in the kidneys of the two species, as well as in the skeletal muscle of the shrew. A significantly lower vitamin E concentration is found in all organs of young shrews before wintering, compared to adult overwintered animals, while in the bank vole no such age-related differences are found. Interspecies differences in the levels of vitamins A and E in the liver of overwintered animals are revealed. The results obtained show that the concentration of vitamins A and E in the tissues of the bank vole and the common shrew is determined by metabolic processes and the ecological characteristics of the species. The level of vitamins in the common shrew depends largely on age.

Comprehensive studies of three Attic plastic vessels dated to the 4th century BC from the State Historical Museum collection have been performed. The use of  X-ray tomography (XRT), large-scale X-ray fluorescence (XRF) mapping, energy-dispersive X-ray microanalysis (EDX) under scanning electron microscopy (SEM), and synchrotron X-ray diffraction (XRD-SR) analysis made it possible to study in detail their state of preservation (including restoration traces) and the manufacturing technology, as well as to identify the pigments used in painting the surface. Based on the pigment residues, identified visually and on XRF maps, a reconstruction of the polychrome painting of the vessels was proposed. Because of the poor state of preservation of the coating on the surface of two vessels, the reconstruction of their possible polychrome painting was performed based on a comparison with known analogues.

Individual resoluteness during the resumption of feeding of nestlings was examined in tests involving the presentation of an unfamiliar object near the nests of the pied flycatcher ( Ficedula hypoleuca ) in a natural environment. Over the course of five breeding seasons, 229 individuals were tested, 41 of which were tested 2 to 4 times. Repeat testing of the same birds was conducted at different nests with intervals ranging from 3 to 1103 days (Med = 367). We took into account the number and age of nestlings, nesting periods, the sex and age of the individual and its partner, the presence of molting, the intensity of nestling feeding, the behavior of the partner, as well as the presence of simultaneous bigamy in the male. We revealed a significant repeatability of test results over substantial time intervals ( R = 0.21), indicating the individual’s stability over time in response (boldness) to changing conditions in the natural environment.

Ocean deoxygenation has been observed in all major ocean basins over the past 50 yr. Although this signal is largely consistent with oxygen changes expected from anthropogenic climate change, the contribution of external forcing to recent deoxygenation trends relative to natural internal variability is yet to be established. Here we conduct a formal optimal fingerprinting analysis to investigate if external forcing has had a detectable influence on observed dissolved oxygen concentration ([O2]) changes between ∼1970 and ∼1992 using simulations from two Earth System Models (MPI-ESM-LR and HadGEM2-ES). We detect a response to external forcing at a 90% confidence level and find that observed [O2] changes are inconsistent with internal variability as simulated by models. This result is robust in the global ocean for depth-averaged (1-D) zonal mean patterns of [O2] change in both models. Further analysis with the MPI-ESM-LR model shows similar positive detection results for depth-resolved (2-D) zonal mean [O2] changes globally and for the Pacific Ocean individually. Observed oxygen changes in the Atlantic Ocean are indistinguishable from natural internal variability. Simulations from both models consistently underestimate the amplitude of historical [O2] changes in response to external forcing, suggesting that model projections for future ocean deoxygenation may also be underestimated.

The results of complementary studies of Al films grown by magnetron sputtering at room temperature are presented. The films were obtained on standard Si(111) substrates without and with a ∼20 nm aluminum (homobuffer) layer preliminarily grown on their surface at 400°C. The interdependence of the morphology, microstructure, and hardness of Al films on the state of the substrate surface was studied by the HRXRR, XRD, SEM, EDS, AFM, and Nano Indenter (ASTM) methods. It is shown that the formation of homobuffer layers on the substrate surface makes it possible to control the structural and mechanical properties of thin aluminum films.

Phenotypic plasticity and resistance to climatic conditions allowed the wild boar Sus scrofa L. to expand its historical range and move away its Northern border. For the adaptation to living at the periphery of its range under severe conditions of the North, the status of vitamins A and E, which are natural antioxidants critical for growth, reproduction and immunity maintenance, is of vital importance. The aim of this work was to investigate the content of retinol, α-tocopherol, and the low-molecular-weight antioxidant glutathione (GSH) in the liver, kidney, heart, skeletal muscle, lungs, and spleen of the wild boars ( n = 65) aged 0.5–8 years, living in the Northwest of Russia. Our results indicate that the studied animals practically did not differ in the retinol content from their counterparts living in the Central and Southern Europe, but had lower tissue α-tocopherol levels, which is probably due to the limited food resources and harsh climatic conditions of the cold season in the North. Vitamin and GSH levels in most tissues were comparable in piglets and adult animals. With age, retinol and α-tocopherol accumulated in the liver and kidney, while α-tocopherol alone accumulated in the heart, which is typical for other mammalian species. An increase in the GSH level was found in the lungs of animals over 5 years of age. The revealed vitamin status, which was formed in the wild boar under conditions of the Russia’s Northwest, as well as the peculiarities of the age-related dynamics of the above indices, may serve a compelling evidence for the successful adaptation of this species to inhabiting the northern periphery of its range, as confirmed by the growth of its population.