Methane is one of the most important greenhouse gases. Methane emissions from land sources to the atmosphere often occur in the form of short but intense outbursts, which are difficult to measure. We developed a new software tool based on wavelets which reliably quantifies such methane outbursts. Using these results as a reference, our study shows that regular data processing using the eddy-covariance technique provides solid long-term methane budgets, but short-term uncertainties can be high.

We investigated the fish and scavenger community after a deep seafloor disturbance experiment intended to simulate the effects of deep-sea mining. Fish density returned to background levels after several years; however the dominant fish was rarely found in ploughed habitat after 26 years. Given the significantly larger scale of industrial mining, these results could translate to population-level effects. The abyssal fish community at the site was similar to that in the Clarion–Clipperton Zone.

We estimate the uncertainties associated with three global satellite-derived burned area estimates. The method provides unique uncertainties for the three estimates at the global scale for 2001–2013. We find uncertainties of 4 %–5.5 % in global burned area and uncertainties of 8 %–10 % in the frequently burning regions of Africa and Australia.

Microbial iron reduction participates in important biogeochemical cycles. In the last decade iron reduction has been observed in many aquatic sediments below its classical zone, in the methane production zone, suggesting a link between the two cycles. Here we present evidence for microbial iron reduction in the methanogenic depth of the oligotrophic SE Mediterranean continental shelf using mainly geochemical and microbial sedimentary profiles and suggest possible mechanisms for this process.

Our understanding of the drivers of hypoxia fundamentally hinges on patterns of water circulation and vertical mixing that can be difficult to resolve in coastal regions. We identified areas prone to oxygen loss in a complex marine area without knowledge of biogeochemical properties, using only parameters which describe the enclosed seafloors with restricted water exchange. Our approach could help nutrient abatement measures and pinpoint areas where management actions are most urgently needed.

Traditionally a mass-dependent correction is made when measuring the radiocarbon composition in organic samples. This correction has not been evaluated for the soil gas environment where gas transport processes are important. Here, we show using theory that this traditional correction is not appropriate for estimating the radiocarbon composition of soil biological production. We also propose a new solution that accounts for soil gas transport processes.

It is estimated that natural wetlands emit approximately 30 % of all the methane released to the atmosphere; yet these estimates are highly uncertain due to the complexity of biological, chemical, and physical processes controlling methane emissions. In this study, we explore how some of these key processes drive methane emissions in a temperate peat bog. We show that the composition of microbial methane cyclers in the upper portion of the peat drives the velocity of methane release to the air.

The carbon stored in soils is the largest reservoir of organic carbon on land. In the context of greenhouse gas emissions and a changing climate, it is very important to understand how stable the carbon in the soil is and why. The deeper parts of the soil have often been overlooked even though they store a lot of carbon. In this paper, we discovered that although deep soil carbon is expected to be old and stable, there can be a significant young component that cycles much faster.

Nitrous oxide (N₂O) is an important greenhouse gas and the major stratospheric ozone-depleting substance; therefore, mitigation of anthropogenic N₂O emissions is needed. To trace N₂O-emitting source processes, in this study, we observed N₂O isotopocules above an intensively managed grassland research site with a recently developed laser spectroscopy method. Our results indicate that the domain of denitrification or nitrifier denitrification was the major N₂O source.

Antarctic marine calcifying organisms are threatened by regional climate change and ocean acidification. Future projections of regional carbonate production are challenging due to the lack of historical data combined with complex climate variability. We present a 6-year record of flux, morphology and geochemistry of an Antarctic planktonic foraminifera, which shows that their growth is most sensitive to sea ice dynamics and is linked with the El Niño–Southern Oscillation.

This paper provides a preliminary data set for dissolved nutrient abundance in the Dark Zone of the Greenland Ice Sheet. This 15-year marked darkening has since been attributed to glacier algae blooms, yet has not been accounted for in current melt rate models. We conclude that the dissolved organic phase dominates surface ice environments and that factors other than macronutrient limitation control the extent and magnitude of the glacier algae blooms.