Integrated Methane Inversion (IMI) 2.0: an improved research and stakeholder tool for monitoring total methane emissions with high resolution worldwide using TROPOMI satellite observations

Geoscientific model development, vol. 18, pp. 3311–3330

Abstract

Abstract. Satellite observations of atmospheric methane are a powerful resource for helping to quantify methane emissions in service of climate action. The inverse methods needed to exploit these observations require a high level of scientific and technical expertise as well as access to large computational and data processing resources. The Integrated Methane Inversion (IMI) is an open-access cloud computing tool designed for researchers and non-expert users to obtain total sector-resolved methane emissions worldwide at up to 0.25°×0.3125° (≈25×25 km2) resolution by analytical inversion of TROPOMI satellite observations with closed-form error characterization. Here we describe IMI version 2.0 with vastly expanded capabilities relative to the original version. Major developments include: (i) a new blended TROPOMI+GOSAT dataset for higher data quality, (ii) incorporation of point source observations in state vector construction, (iii) order-of-magnitude speedup in Jacobian matrix construction, (iv) improved error characterization through use of super-observations, (v) improved methods for initial and boundary conditions, (vi) adaptive spatial resolution linked to observational information content, (vii) option to optimize tropospheric OH (main methane sink), (viii) global inversion capability, (ix) Kalman filter option for continuous monitoring of emissions, (x) updated default prior emission inventories, (xi) option for lognormal error probability density functions to characterize emissions, (xii) additional output visualization (sectoral emissions, temporal variability), and (xiii) containerization to facilitate download to local computing facilities and operation as part of the US GHG Center. A 2023 annual inversion with 28-day temporal resolution for the contiguous US (CONUS) is presented as demonstration of IMI 2.0 capabilities.

Authors 19

1. Lucas Estrada

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

2. Daniel J. Varon

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

3. Melissa Payer Sulprizio

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

4. Hannah O. Nesser

   Jet Propulsion Laboratory

   Affiliation as printed

   Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA

5. Zichong Chen

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

6. Nicholas Balasus

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

7. Sarah E. Hancock

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

8. Megan He

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

9. James D. East

   Harvard University

   Affiliation as printed

   School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA

10. Todd A. Mooring

    Harvard University

    Affiliation as printed

    Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA

11. Alexander Oort Alonso
12. Joannes D. Maasakkers Aachen SRON Netherlands Institute for Space Research

    Space Research Organisation Netherlands

    Affiliation as printed

    SRON Netherlands Institute for Space Research, Leiden, the Netherlands

13. Ilse Aben Aachen SRON Netherlands Institute for Space Research

    Space Research Organisation Netherlands

    Affiliation as printed

    SRON Netherlands Institute for Space Research, Leiden, the Netherlands

14. Sabour Baray

    Environment and Climate Change Canada

    Affiliation as printed

    Environment and Climate Change Canada, Toronto, ON, Canada

15. K. W. Bowman

    Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA

16. John R. Worden

    Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA

17. Felipe J. Cardoso‐Saldaña
18. Emily K. Reidy

    ExxonMobil (United States)

    Affiliation as printed

    ExxonMobil Technology and Engineering Company, Spring, TX, USA

19. Daniel J. Jacob

    Harvard University

    Affiliation as printed

    School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, USA