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During the latest Eocene, declining atmospheric CO₂ levels led to the inception of the Antarctic ice sheet. Simulations suggest that the deepening of the Drake Passage caused climate changes that enhanced continental weathering and CO₂ drawdown.

This paper presents simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the Atlantic meridional overturning circulation. It is found that variations in atmospheric carbon dioxide levels on millennial time scales are dominated by slow changes in the deep ocean inventory of biologically-sequestered carbon and are correlated to Antarctic temperature and Southern Ocean stratification. The results suggest that ocean circulation changes were the primary mechanism that drove glacial fluctuations in carbon dioxide and nitrous oxide fluctuations on millennial time scales.

Global marine fish harvest increased over the 20th century, reaching a peak in the 1990s. Here, Galbraith and colleagues analyse a model combining both ecological and economic drivers to weigh the factors most likely to contribute to long-term changes in fish harvests.

Ocean warming during the last deglaciation decreased the solubility of oxygen. A global compilation of marine sediment records shows that the deglacial trend of deoxygenation was overprinted by changes in ocean circulation and marine productivity.

The marine nitrogen cycle was altered during the transition from glacial to interglacial conditions. An analysis of δ¹⁵N records throughout the world’s oceans suggests that rates of denitrification in the water column accelerated during the last deglaciation.

Atmospheric CO₂ levels varied across glacial–interglacial cycles. An analysis of ice-core CO₂ identifies a lower limit to glacial CO₂ concentrations, which may reflect a negative biosphere feedback to decreasing CO₂ levels.

An improved, fully re-annotated Aedes aegypti genome assembly (AaegL5) provides insights into the sex-determining M locus, chemosensory systems that help mosquitoes to hunt humans and loci involved in insecticide resistance and will help to generate intervention strategies to fight this deadly disease vector.

Understanding the failure of commercial Cu/SAPO-34 selective catalytic reduction (SCR) catalysts at an atomic level is vital for the synthesis of more robust catalysts. Here the authors unravel the mysterious failure of Cu/SAPO-34 SCR catalysts via application of model catalysts and 2-dimensional pulsed electron paramagnetic resonance

An integrated analysis of de novo and inherited coding variants in 42,607 individuals with autism spectrum disorder identifies 60 risk genes of which five have not previously been associated with neurodevelopmental disorders.

Support Brønsted acid strength and density play important kinetically relevant roles in low temperature NH3-SCR over Cu-exchanged small pore zeolite catalysts. Here the authors demonstrate Brønsted acid sites facilitate hydrolysis and intercage transfer of Cu^II(NH₃)₄ intermediates.

Geochemical records from ocean sediment cores are used to shed light on the composition and ventilation of water in the deep North Pacific during the Last Glacial Maximum. A poorly-ventilated water mass that was rich in respired carbon dioxide occupied the North Pacific abyss during the Last Glacial Maximum, and that ventilation of the abyss increased during deglaciation, releasing carbon dioxide into the atmosphere.

Wood density is a key control on tree biomass, and understanding its spatial variation improves estimates of forest carbon stock. Sullivan et al. measure >900 forest plots to quantify wood density and produce high resolution maps of its variation across South American tropical forests.

The authors analyse tree responses to an extreme heat and drought event across South America to understand long-term climate resistance. While no more sensitive to this than previous lesser events, forests in drier climates showed the greatest impacts and thus vulnerability to climate extremes.

Light sheet microscopy using a scanned Bessel beam in combination with structured illumination or two-photon excitation reduces photobleaching and phototoxicity, improves axial resolution and allows isotropic three-dimensional imaging. The authors demonstrate performance of the method via fast volumetric subcellular imaging of several dynamic processes in single living cells.

Tree mortality has been shown to be the dominant control on carbon storage in Amazon forests, but little is known of how and why Amazon forest trees die. Here the authors analyse a large Amazon-wide dataset, finding that fast-growing species face greater mortality risk, but that slower-growing individuals within a species are more likely to die, regardless of size.

This study uses global datasets of marine prokaryotes to reveal that prokaryotic biomass varies by just under 3-fold across the global surface ocean, while metabolic activity increases by more than one order of magnitude from polar to tropical coastal and upwelling regions. The findings also suggest that shifts under climate change could lead to an increasingly microbial-dominated ocean.

The authors construct a process-based hunter-gatherer population model embedded within a global terrestrial biosphere model that reveals a strong effect of growing season length on population density via diet composition.

Use of an enhanced suite of marine ecosystem models and Earth system model outputs from Phase 6 of the Coupled Model Intercomparison Project (CMIP6) reveals greater decline in mean global ocean animal biomass than previously projected under both strong-mitigation and high-emissions scenarios.

This study examines productivity and workforce dynamics in the world’s fisheries over six decades, finding that the natural limits of fish stocks combined with technological advances have led to diminishing returns per fisher.

The role of non-structural carbohydrates (NSC) in mediating the impacts of drought in tropical trees is unclear. Here, the authors analyse leaf and branch NSC in 82 Amazon tree species across a Basin-wide precipitation gradient, finding that allocation of leaf NSC to soluble sugars is higher in drier sites and is coupled to tree hydraulic status.

By comparing neural responses to diverse visual stimuli measured with a standardized two-photon imaging pipeline, the authors reveal response specializations within the mouse visual cortex.

The Southern Ocean is a major site of open-ocean deep convection. Using observational data and model simulations, it is found that surface waters have freshened since the 1950s and deep convection has weakened, and could cease, as a result of the freshening. This has implications for bottom-water formation, ocean heat and carbon storage.

Inventory data from 90 lowland Amazonian forest plots and a phylogeny of 526 angiosperm genera were used to show that taxonomic and phylogenetic diversity are both predictive of wood productivity but not of biomass variation.

Throughout the ocean, countless small animals swim to depth in the daytime, presumably to seek refuge from large predators. An analysis of backscatter data from acoustic Doppler profilers suggests that migration intensifies oxygen depletion in the upper margin of oxygen minimum zones.

A pan-Amazon study of forests shows large variations in drought tolerance traits and finds that forests in regions of pronounced climate change are losing biomass and may be operating beyond their hydraulic limits.

While numerous studies have indicated that carbon export to the deep ocean was greater during glacial periods, quantification is lacking. Here, via analysis of hundreds of sediment cores, the authors show carbon accumulation rate was 50% higher during glacial maxima than during interglacials.

The amount of carbon stored in the deep ocean varied over glacial–interglacial cycles. Southern Ocean sediments from the past 360,000 years show that carbon storage also fluctuated within glacial periods, in concert with the fertilization of the Southern Ocean by wind-borne dust.

Traditional studies of subjective well-being explain national differences using social and economic proxy variables. Here the authors build on this approach to estimate how global human well-being might evolve over the next three decades, and find that changes in social factors could play a much larger role than changes in economic outcomes.

Fishing has had a profound impact on global reef shark populations, and the absence or presence of sharks is strongly correlated with national socio-economic conditions and reef governance.

High expression of Mcl-1 promotes tumorigenesis and resistance to anticancer therapies. Here they report a macrocyclic molecule with high selectivity and affinity for Mcl-1 that exhibits potent anti-tumor effects as single agent and in combination with bortezomib or venetoclax in preclinical models of multiple myeloma and acute myeloid leukemia.

Enhanced upwelling and CO₂ degassing from the subpolar North Pacific during a warm event 14,000 years ago may have helped keep atmospheric CO₂ levels high enough to propel the Earth out of the last ice age.

Historical phases of ocean oxygen minimum are associated with near extinctions of mesopelagic fish, suggesting risks of future deoxygenation to marine fisheries due to warming, according to an analysis of a fish otolith record from a Mediterranean sediment core.

A downward expansion of oxygen depletion in the eastern Pacific Ocean during the last ice age suggests an increase in the respired carbon reservoir, contributing to the lower levels of atmospheric carbon dioxide during this period.

Global ocean oxygen concentrations have been declining, with rates varying regionally. The retreat of the Labrador Current, allowing more low-oxygen subtropical waters to the coastal and shelf waters, drives the rapid decline observed in the northwest Atlantic Ocean.

A reconstruction of changes in ocean oxygenation throughout the last glacial cycle shows that respired carbon was removed from the deep Southern Ocean during deglaciation and Antarctic warm events, consistent with a prominent role of reduced iron fertilization and enhanced ocean ventilation, modifying atmospheric carbon dioxide concentrations over the past 80,000 years.

Assessing development challenges for fisheries-dependent countries based on analyses of interactions and trade-offs between goals focusing on food, biodiversity and climate change.