Research articles

Carbonyl sulphide is taken up by plants, and could potentially serve as a powerful proxy for photosynthetic carbon dioxide uptake. Field measurements in Israel suggest that carbonyl sulphide fluxes provide an independent constraint on indirect estimates of ecosystem photosynthesis.

Predators can potentially influence the exchange of carbon dioxide between ecosystems and the atmosphere. Predator manipulation experiments with fish and invertebrates in a range of freshwater systems suggest that freshwater carbon dioxide emissions are reduced in the presence of predators.

The Atlantic meridional overturning circulation is a key component of the climate system. Data and climate model reconstructions reveal a decline in the strength of the overturning circulation during the Heinrich1 and Younger Dryas cold events of the last glacial period.

The last glacial period was marked by dramatic climate fluctuations. Sediment records from the Cariaco Basin and the Arabian Sea suggest that cooling in the North Atlantic region was tightly coupled with a southward displacement of the intertropical convergence zone and a weakening of the Indian summer monsoon.

The topography hidden beneath the East Antarctic ice sheet has been unveiled by airborne surveys. Dating of detrital mineral grains reveals that, in contrast to low pre-glacial erosion rates, strong localized erosion has occurred since the expansion of the ice sheet, suggesting a dynamic early ice sheet.

Coccolithophores are a key component of the oceanic food web, and may be sensitive to environmental changes. Modern experiments and an assessment of the fossil record suggest that the response of individual species to a period of ocean acidification in the past may have affected the evolutionary success of these species’ lineages.

During the Eocene–Oligocene transition, a permanent ice sheet was established on Antarctica. Marine sediment geochemistry indicates a period of intense weathering associated with the inception of the ice sheet.

The subsurface of Mars could potentially have contained a vast microbial biosphere. An evaluation of the possibility of groundwater upwelling, which might provide clues to subsurface habitability, reveals evidence in the deep McLaughlin crater for clays and carbonates that probably formed in an alkaline, groundwater-fed lacustrine setting.

Diogenite meteorites are thought to represent mantle rocks that formed as cumulates in magma chambers on 4 Vesta or a similar differentiated asteroid. Microstructural analysis of olivine grains from a diogenite meteorite show that the preferred orientation of their crystal lattice was formed through plastic deformation, indicating dynamic, planet-like processes in its parent body.

The causes for rising temperatures along the Antarctic Peninsula over the past few thousand years have been debated. Analyses of diatom geochemistry and assemblage ecology from Palmer Deep off the western margin of the Antarctic Peninsula reveal that atmospheric processes have dominated glacial ice discharge during the late Holocene.

Deposits of highly vesicular pumice that blanket submarine volcanoes are often attributed to explosive eruptions. Density and textural analysis of clasts dredged from the submarine Macauley Volcano, southwest Pacific Ocean, however, reveal an eruptive style that is neither explosive nor effusive, with clasts instead forming from buoyant detachment of a magma foam.

Naturally occurring bromine- and iodine-containing compounds substantially reduce regional, and possibly global, tropospheric ozone levels. Experimental and model results suggest that the reaction of ozone with iodide could account for around 75% of observed iodine oxide levels over the tropical Atlantic Ocean.

A period of cooling in the North Atlantic region 8,200 years ago affected climate throughout the Northern Hemisphere. A speleothem record from central China indicates that a dry period lasting 150 years was associated with the 8,200 year event.

Uptake of atmospheric carbon dioxide in the subpolar North Atlantic Ocean declined rapidly between 1990 and 2006. An analysis of oceanographic data suggests that the slowdown of the meridional overturning circulation was largely responsible.

Advances in seasonal forecasting have brought widespread socio-economic benefits. A modelling study suggests that tropospheric forecast skill is enhanced when the forecast model is initialized at the onset of a stratospheric sudden warming event.

The El Niño/Southern Oscillation in the Pacific Ocean influences temperature in other tropical ocean basins. Reanalysis data and model simulations suggest that temperature anomalies in the north tropical Atlantic may also influence the development of La Niña events.

Anammox, anaerobic ammonium oxidation, accounts for over 50% of nitrogen loss in marine ecosystems. A field study in north China reveals hotspots of anammox activity in sediments sampled from land–lake interfaces.