Atmospheric methane (CH4) is the second strongest greenhouse gas and it is emitted to the atmosphere naturally by different sources. It is crucial to define the dimension of these natural emissions in order to forecast changes in atmospheric CH4 mixing ratio in future scenarios. However, CH4 emissions by seagrass ecosystems in shallow marine coastal systems have been neglected although their gl...

The recently reported finding that plant matter and living plants produce significant amounts of the important greenhouse gas methane under aerobic conditions has led to an intense scientific and public controversy. Whereas some studies question the upscaling method that was used to estimate the global source strength, others have sug5 gested that experimental artifacts could have caused the re...

Lakes are important components of the global methane (CH4) cycle. In seasonally ice-covered lakes, CH4 transported by ebullition (bubbling) from anoxic sediments gets trapped at the water-ice interface. If not oxidized by methane-oxidizing bacteria (MOB), this can potentially lead to high episodic CH4 emissions at icemelt. To understand the fate of CH4 trapped below ice, we measured depth-distr...

The prediction of methane outputs from ruminant livestock data at farm, national, and global scales is a vital part of greenhouse gas calculations. The objectives of this work were to quantify the effect of physiological stage (lactating or nonlactating) on predicting methane (CH4) outputs and to illustrate the potential improvement for a beef farming system of using more specific mathematical ...

Simultaneous observations from the Infrared Atmospheric Sounding Interferometer (IASI) and from the Advanced Microwave Sounding Unit (AMSU), launched together onboard the European MetOp platform in October 2006, are used to retrieve a mid-to-upper tropospheric content of methane (CH4) in clear-sky conditions, in the tropics, over sea, for the first 16 months of operation of MetOp (July 2007–Oct...

Sources and sinks of methane (CH4) are critical for understanding global biogeochemical cycles and their role in climate change. A growing number of studies have reported that CH4 concentrations in cave ecosystems are depleted, leading to the notion that these subterranean environments may act as sinks for atmospheric CH4. Recently, it was hypothesized that this CH4 depletion may be caused by r...

from 2 IBBA workshop on methane emissions in Kiel, Germany, September 4 2014. Full-scale quantification of CH4 emissions from wastewater treatment plants and biogas facilities. Antonio Delre, Jacob Mønster, Charlotte Scheutz DTU Environment – Technical University of Denmark

A novel porous aromatic framework based on tetra-(4-anilyl)-methane and cyanuric chloride has been designed and synthesized successfully, which possesses permanent porosity and high selectivity of CO2 towards CH4.

In methanogenic environments Methanosarcinaceae are beside Methanosaetaceae the only acetate-consuming family of archaea and thus important contributors to the formation of the greenhouse gases methane and carbon dioxide. In this study, the carbon isotope fractionation during this process was determined for two species of the Methanosarcinaceae family, M. barkeri and M. acetivorans. The calcula...

The low O2 content of the Archean atmosphere implies that methane should have been present at levels approximately 10(2) to 10(3) parts per million volume (ppmv) (compared with 1.7 ppmv today) given a plausible biogenic source. CH4 is favored as the greenhouse gas that countered the lower luminosity of the early Sun. But abundant CH4 implies that hydrogen escapes to space (upward arrow space) o...