Environmental Science and Engineering Seminar

Methane (CH4) is the second most important greenhouse gas after carbon dioxide. The current atmospheric CH4 abundance is more than 160% greater than the pre-industrial level, and the growth in 2020-2022 was the fastest since the systematic measurement started in the 1980s. This rapid increase is a challenge for reaching the climate mitigation goals of the Paris Agreement and Global Methane Pledge from COP26, which requires steep cuts in CH4 emissions by 2030. Slowing or reversing the accelerating growth in atmospheric CH4 will require an improved understanding of the regional and global CH4 budget, which is currently under-constrained. The stable carbon isotope of CH4 is a useful tracer to constrain the CH4 budget. To provide quantitative estimates of global CH4 emissions consistent with observed patterns of atmospheric CH4 and its stable isotope, we have improved NOAA's atmospheric CH4 data assimilation system, the CarbonTracker-CH4. In this presentation, I will explain why studying CH4 is interesting and important for climate mitigation, summarize the results of CarbonTracker-CH4, and discuss future opportunities for implementing multi-source datasets and advanced AI/ML approaches.