Measuring methane emissions from offshore oil and gas facilities off the Central African coast
In mid-January 2023, DLR scientists reported on their first results from the METHANE-To-Go Africa measurement campaign at the "Oman Conference for Environmental Sustainability" in Muscat.
In September 2022, DLR scientists from the Institute of Atmospheric Physics had successfully conducted an aircraft measurement campaign to determine methane emissions from offshore oil & gas (O&G) facilities off the Central African coast. This campaign is part of the IMEO (International Methane Emissions Observatory) program, which is funded by UNEP (United Nations Environment Programme). IMEO aims to characterize anthropogenic methane emissions worldwide in order to develop and implement targeted reduction measures in a timely manner.
Methane (CH4) is the second most important greenhouse gas emitted by humans after carbon dioxide (CO2). Anthropogenic CH4 emissions, from which a large part originates from oil and gas production, result in increasing atmospheric concentrations since the beginning of industrialization, leading to atmospheric warming. To decelerate this warming and meet the 1.5°C target of the Paris Climate Agreement, anthropogenic emissions must be reduced at short time-scales. In this context, CH4 in particular has become the focus of attention in recent years (Global Methane Pledge, COP26 in Glasgow), as it is particularly interesting for immediate mitigation measures due to its relatively short lifetime (~10 years) compared to CO2 (~100-1000 years). However, efficient mitigation requires extensive knowledge of respective sources. The goal of the METHANE-To-Go project is to characterize CH4 emissions specifically from the O&G sector to provide the basis for emission reduction strategies.
During the METHANE-To-Go Africa measurement campaign, we were able to conduct the first measurements of CH4 emissions from Central African O&G production. Approximately one-third of all African oil production occurs in this region (BP Statistical Review of World Energy), predominantly at offshore facilities. Despite the high production volume, the related CH4 emissions are largely unknown, basically due to the lack of scientifically independent measurements in this region until now. The dataset obtained during the measurement campaign allows to accurately characterize the emissions in this area and thus provides a valuable contribution to the global effort to better understand CH4 sources.
DLR / G. Neumann (CC BY-NC-ND 3.0)
During our measurement campaign, a total of 15 research flights were conducted off the coasts of Gabon and Angola using the DLR Falcon. The team was based in the Gabonese capital Libreville for three weeks. Equipped with state-of-the-art in-situ measurement systems, specially modified for operation on a research aircraft, 50 hours of scientific data were collected. Besides the atmospheric CH4 concentration, other trace gases (e.g. CO2, CO, C2H6, SO2) and aerosol parameters were measured. This will allow to not only determine the CH4 emissions of the study region, but also to identify the underlying emission processes. Through a close collaboration with our local partners, the Gabonese space agency AGEOS (L'Agence Gabonaise d'Etudes et d'Observations Spatiales) and the Angolan O&G agency ANPG (Agência Nacional de Petróleo, Gás e Biocombustíveis), all offshore O&G areas of both countries could be sampled several times during the campaign period and hence, to gather a representative data set for this region.
DLR / K.-D. Gottschaldt (CC-BY-ND-NC 3.0)
In the coming months, DLR scientists will process, analyse and publish the scientific results of the measurement campaign. With the help of our local partners, who are familiar with the characteristics of the local O&G exploration, our results finally will be evaluated and compared with the data provided by the operators of the facilities.