Offshore western Svalbard plumes of gas bubbles rise from the seafloor at the landward limit of the gas hydrate stability zone (LLGHSZ; 400 m water depth). It is hypothesized that this methane may, in part, come from dissociation of gas hydrate in the underlying sediments in response to recent warming of ocean bottom waters. To evaluate the potential role of gas hydrate in the supply of methane...

This paper presents a systematic methodology for design of landfill methane migration control systems. The key to the methodology is that it tests for deficiencies in the conceptual model (working hypothesis) of methane migration, correcting potential design flaws in the landfill methane control system before commencing design and construction. The testing is accomplished by (1) a field investi...

It is established that late-twentieth and twenty-first century ocean warming has forced dissociation of gas hydrates with concomitant seabed methane release. However, recent dating of methane expulsion sites suggests that gas release has been ongoing over many millennia. Here we synthesize observations of ∼1,900 fluid escape features--pockmarks and active gas flares--across a previously glaciat...

Ozone and methane are chemically active climate-forcing agents affected by climate–chemistry interactions in the atmosphere. Key chemical reactions and processes affecting ozone and methane are presented. It is shown that climate-chemistry interactions have a significant impact on the two compounds. Ozone, which is a secondary compound in the atmosphere, produced and broken down mainly in the t...

Natural methane emission from geological sources has recently been recognized as an important component in the atmospheric methane budget. Some authors have only focused their attention on submarine gas seepage and gas hydrates (Judd, 2000; Kvenvolden et al., 2001), recent studies have suggested that mud volcanoes (MVs) on land and microseepage in hydrocarbon-prone areas are also significant ge...

Abstract: Reduction of the Titanium dioxide, TiO2, by methane was investigated in this work. The thermodynamic of reaction was examined and found favorable. The reaction of titanium dioxide with methane was carried out in the temperature range 1150°C to 1450°C at atmospheric pressure with industrial high porosity pellets prepared from titanium dioxide powder. The evolved gas analyzing method wa...

Saponins have been considered as promising natural substances for mitigating methane emissions from ruminants. However, studies reported that addition of saponin-rich sources often arrived at contrasting results, i.e. either it decreased methane or it did not. The aim of the present study was to assess ruminal methane emissions through a meta-analytical approach of integrating related studies f...

Recent interest in greenhouse gas emissions from ruminants, such as cattle, has spawned a need for affordable, precise, and accurate methods for the measurement of gaseous emissions arising from enteric fermentation. A new head hood system for cattle designed to capture and quantify emissions was recently developed at the University of California, Davis. The system consists of two head hoods, t...

Methane is a substantial contributor to climate change. It also contributes to maintaining the background levels of tropospheric ozone. Among a variety of CH4 sources, current estimates suggest that CH4 emissions from oil and gas processes account for approximately 20% of worldwide anthropogenic emissions. Here, we report on observational evidence of CH4 emissions from offshore oil and gas plat...

Remote sensing plays a significant role in the estimation of methane and monitoring wetlands flooding duration and extent [1]. Methane is the second largest contributor to the present day greenhouse gas effect [3]. However there are considerable uncertainties in the magnitude of this biogenic emission [2]. For instance, the amount of methane emissions from the Okavango Delta is not known, which...