Year-end Sale % OFF 
Abstract
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 platforms in Southeast Asia, detected by a highly time-resolved spectroscopic monitoring technique deployed onboard cargo ships of opportunity. We often encountered CH4 plumes originating from operational flaring/venting and fugitive emissions off the coast of the Malay Peninsula and Borneo. Using night-light imagery from satellites, we discovered more offshore platforms in this region than are accounted for in the emission inventory. Our results demonstrate that current knowledge regarding CH4 emissions from offshore platforms in Southeast Asia has considerable uncertainty and therefore, emission inventories used for modeling and assessment need to be re-examined.
Highlights
Methane is a substantial contributor to climate change
The 16 peaks observed in the Borneo area with DCH4/DCO2 ratios higher than 20 ppb/ppm were explained by the mixing of flaring and fugitive emissions. We chose those peaks with DCH4/DCO2 ratios higher than 20 ppb/ppm for further analysis. We used these observed CH4 peaks to estimate the CH4 emission rates based on a mass balance approach[25,26,27]
In equation (1), u is the mean horizontal wind speed along the plume axis, a is the angle between the ship transect and the perpendicular to the plume axis, ZMBL is the depth of the marine boundary layer (MBL), n is the average molar density of air within the MBL, y is the distance from the plume axis, fCH4(y) is the observed CH4 mole fraction at y, and C0(y) is the background CH4 mole fraction at y
Summary
Methane is a substantial contributor to climate change. It contributes to maintaining the background levels of tropospheric ozone. Regular aircraft observations from the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) program suggest strong biogenic emissions from India that cannot be attributed solely to rice cultivation[12]. These studies show that our current understanding regarding the sources of CH4 emissions is inadequate and that greater effort is needed to obtain better knowledge both of the strength of CH4 emissions and of the distribution of the sources. CH4 (ppb) where strong CH4 peaks were observed off the east coast of the Malay Peninsula and the northwest coast of Borneo, and we examine the emission sources responsible for these observed CH4 peaks
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
