The effects of historical ozone changes on Southern Ocean heat uptake and storage
"Atmospheric ozone concentrations have dramatically changed in the last five decades of past century. Herein we explore the effects of historical ozone changes that include stratospheric ozone depletion on Southern Ocean heat uptake and storage, by comparing CESM1 large ensemble simulations with fixed-ozone experiment. During 1958–2005, the ozone changes contribute to about 50% of poleward intensification of the Southern Hemisphere westerly winds in historical simulations, which intensifies the Deacon Cell and residual meridional overturning circulation, thus contributing to heat redistribution[...]"
Source: Climate Dynamics
Authors: Shouwei Li et al.
Biogeochemical evolution and organic carbon deposition on the Northwestern European Shelf during the Toarcian Ocean Anoxic Event
"The Toarcian Oceanic Anoxic Event (T-OAE, ~183 Ma) represents a well-known episode of organic-rich deposition, which is accompanied by a substantial negative carbon-isotope excursion (CIE). Underpinning the relationships between the carbon-cycle perturbation, ocean anoxia, primary productivity feedbacks and the enrichment of sedimentary organic carbon remains a major challenge. Here, we present high-resolution geochemical[...]"
Source: Science Direct
Authors: Alexander J.P.Houben et al.
Reactive Nitrogen Cycling in the Atmosphere and Ocean
"The budget of reactive nitrogen (Nr; oxidized and reduced inorganic and organic forms of nitrogen) has at least doubled since the preindustrial era due to human activities. Excess Nr causes significant detrimental effects on many terrestrial and aquatic ecosystems; less is known about the impact on the open ocean. Nr deposition may already rival biological N2 fixation quantitatively and will likely continue to rise.[...]"
Source: Annual Review of Earth and Planetary Sciences
Authors: Katye E. Altieri et al.
Marine Litter Windrows: A Strategic Target to Understand and Manage the Ocean Plastic Pollution
"Windrow is a long-established term for the aggregations of seafoam, seaweeds, plankton and natural debris that appear on the ocean surface. Here, we define a “litter windrow” as any aggregation of floating litter at the submesoscale domain (<10 km horizontally), regardless of the force inducing the surface convergence, be it wind or other forces such as tides or density-driven currents. The marine litter windrows observed to date usually form stripes[...]"
Authors: Andrés Cózar et al.
Heavy iron in large gem diamonds traces deep subduction of serpentinized ocean floor
"Subducting tectonic plates carry water and other surficial components into Earth’s interior. Previous studies suggest that serpentinized peridotite is a key part of deep recycling, but this geochemical pathway has not been directly traced. Here, we report Fe-Ni–rich metallic inclusions in sublithospheric diamonds from a depth of 360 to 750 km with isotopically heavy iron (δ56Fe = 0.79 to 0.90‰) and unradiogenic osmium[...]"
Authors: Evan M. Smith et al.
Dissolved Organic Matter in the Upwelling System off Peru: Imprints of Bacterial Activity and Water Mass Characteristics
"Microbial degradation of dissolved organic matter (DOM) contributes to the formation and preservation of oxygen minimum zones (OMZs) in the ocean, but information on the spatial distribution and molecular composition of DOM in OMZ regions is scarce. We quantified molecular components of DOM that is, dissolved amino acids (DAA) and dissolved combined carbohydrates (DCCHO), in the upwelling region off Peru. We found the highest concentrations of DCCHO in fully oxygenated[...]"
Source: Advancing Earth and Space Science
Authors: Anja Engel et al.
Ocean currents as a potential dispersal pathway for Antarctica’s most persistent non-native terrestrial insect
"The non-native midge Eretmoptera murphyi is Antarctica’s most persistent non-native insect and is known to impact the terrestrial ecosystems. It inhabits by considerably increasing litter turnover and availability of soil nutrients. The midge was introduced to Signy Island, South Orkney Islands, from its native South Georgia, and routes of dispersal to date have been aided by human activities, with little known about non-human-assisted methods of dispersal. This study is the first to determine the potential for dispersal [...]"
Source: Polar Biology
Authors: Jesamine C. Bartlett et al.
Variable Oxygen Levels Lead to Variable Stoichiometry of Benthic Nutrient Fluxes in a Hypertrophic Estuary
"Harmful blooms of cyanobacteria may extend over long time spans due to self-sustaining mechanisms. We hypothesized that settled blooms may increase redox-dependent P release and unbalance the stoichiometry of benthic nutrient regeneration (NH4+:SiO2:PO43− ratios). We tested this hypothesis in the hypertrophic Curonian Lagoon, the largest in Europe. During summer, at peak chlorophyll and water temperatures, sediment cores were collected over 19 stations representing all the lagoon sedimentary environments. Sediment organic content, granulometry, aerobic respiration, and oxic[...]"
Source: Estuaries and Coasts
Authors: Marco Bartoli et al.
Deoxygenation impacts on Baltic Sea cod: Dramatic declines in ecosystem services of an iconic keystone predator
"The intensified expansion of the Baltic Sea’s hypoxic zone has been proposed as one reason for the current poor status of cod (Gadus morhua) in the Baltic Sea, with repercussions throughout the food web and on ecosystem services. We examined the links between increased hypoxic areas and the decline in maximum length of Baltic cod, a demographic proxy for services[...]"
Authors: Alessandro Orio et al.
Ocean acidification may slow the pace of tropicalization of temperate fish communities
"Poleward range extensions by warm-adapted sea urchins are switching temperate marine ecosystems from kelp-dominated to barren-dominated systems that favour the establishment of range-extending tropical fishes. Yet, such tropicalization may be buffered by ocean acidification, which reduces urchin grazing performance and the urchin barrens that tropical range-extending fishes prefer.[...]"
Source: Nature Climate Change
Authors: Ericka O. C. Coni et al.