Advanced searches left 3/3

Methane emissions - Wiley Online Library

Summarized by Plex Scholar
Last Updated: 08 May 2022

* If you want to update the article please login/register

Positron‐emitting radiotracers spatially resolve unexpected biogeochemical relationships linked with methane oxidation in Arctic soils

Abstract: Cryoturbic features of Arctic soils are prominent, which influence soil-atmosphere methane dynamics that are essential to global climate control. Inherently heterogeneous natural soil matrices, spatial delineation of microbial activity at several scales is experimentally difficult. This is made possible by using positronemitting radiotracers to map millimeter-scale active CH4 uptake areas in Arctic soils with and without diapirism. CH4 uptake spatially associates with higher amounts of inorganic N in diapiric frost boils according to X-ray absorption spectroscopic speciation of living and inactive regions. Ralstonia pickettii is associated with CH4 uptake across soils, as well as relevant CH4 and inorganic N metabolism related genes, according to metagenomic studies. This research reveals the strong correlation between CH4 and N cycles in Arctic soils, as well as potential implications for better understanding future climate.

Source link: https://onlinelibrary.wiley.com/doi/10.1111/gcb.16188


An Inversion Framework for Optimizing Non‐Methane VOC Emissions Using Remote Sensing and Airborne Observations in Northeast Asia During the KORUS‐AQ Field Campaign

We hope to eliminate uncertainties in CH2O and other volatile organic carbon dioxide emissions by assimilation of remote sensing results. During KORUSAQ, we first updated a three-dimensional chemical transport model, GEOSChem, with the inclusion of aromatics and C2H4 in the KORUSv5 anthropogenic emission registry and modest enhancements in simulation of CH2O and O3 versus DC8 aircraft measurements; the mixing ratios for most VOC species is still underestimated. During KORUSAQ, we next constrain VOC emissions using CH2O data from two satellites and the DC8 aircraft. Variations to the VOC speciation from the 4D-Var inversion include increases in biogenic isoprene pollution in Korea and anthropogenic emissions in Eastern China. Our latest hybrid inversion framework can be used for future air quality studies, increasing the benefit of integrating data from existing and new geostationary satellite instruments.

Source link: https://onlinelibrary.wiley.com/doi/10.1029/2021JD035844


High spatiotemporal variability of methane concentrations challenges estimates of emissions across vegetated coastal ecosystems

Abstract: Coastal methane emissions dominate the global ocean CH4 budget, and they can help offset vegetated coastal ecosystems' “blue carbon” storage capacity. We show that the CH4 distribution is spatially patchy across four seasons, in three globally abundant coastal habitats, is both spatially uneventy and highly variable in time. We found 13C eV signatures, habitat-specific CH4 production and consumption routes, daily peak concentration rates that could change > 100 percent within hours in all habitats, and a high thermal sensitivity of the CH4 distribution, which was characterized by apparent activation energies of 1 eV that fueled seasonal variations. Scaling the CH4 distribution from few samples results in significant deviations, according to bootstrapping experiments, and that 50 concentration samples per day are required to determine the nature and sources of the natural variability's uncertainty by up to 70%.

Source link: https://onlinelibrary.wiley.com/doi/10.1111/gcb.16177


Ammonia, nitrous oxide and methane emissions from excreta of cattle receiving rumen undegradable protein

N2O and CH4 emissions were measured using the semi-open static chamber technique with a static closed chamber and NH3 emissions. The mean dung load was 3. 9%, which was 2. 96 and 13. 8% for the middle and end periods, respectively. In summary, RUP's supplementation of beef cattle in pastures with RUP did not reduce NH3, N2O, and CH4 emissions from excreta. Regardless of variations in the type of excreta, type of supplement, and period, the excreta emission factors for the GHGs determined were lower than the default value of the Intergovernmental Panel on Climate Change revised guidelines. To fully comprehend the mechanisms that undergirde RUP's greenhouse gas emissions, further research will be required.

Source link: https://onlinelibrary.wiley.com/doi/10.1002/agj2.21053

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions