Gridded Methane Emission Inventories Driven by Discrete Global Grid Systems (DGGS)

Gridded emission inventories provide a crucial prior estimate for inverse atmospheric analyses of greenhouse gases like methane, enabling more accurate environmental monitoring and climate modeling.

Geospatial locations of high-emission hotspot grids at rHEALPix resolution 5 in Alberta.(b) The difference in methane emissions between this study and Scarpelli et al. (2022), shown at the same resolution.

Objective

Enhance the quality of gridded methane emission inventories in the oil and gas sectors by using Discrete Global Grid Systems (DGGS).

Description

DGGS offer a promising framework for constructing spatially explicit greenhouse gas (GHG) inventories essential for Earth system monitoring and management. This study introduces a novel application of the rearranged Hierarchical Equal Area isoLatitude Pixelization (rHEALPix) DGGS for developing a spatially explicit methane emission inventory in Alberta’s upstream oil and gas sector. Unlike existing inventories built on graticule-based grids, which suffer from size inconsistency and spatial distortions, our work utilizes an equal-area, projection-independent, and hierarchically structured grid system. This enables accurate spatial aggregation, hotspot detection, and inter-grid comparison of methane intensities across latitudes and scales.

The DGGS-based framework not only improves spatial consistency but also provides a scalable architecture for multi-resolution reporting, ranging from facility-level details to basin-wide and national summaries. These findings advance the current state of methane monitoring, reporting, and mitigation planning by offering a uniform spatial structure that supports hotspot identification, trend analysis, and integration with satellite observations. More broadly, the approach contributes to the development of interoperable geospatial infrastructure essential for emission accountability and climate action.

Moreover, the methodology is extendable beyond methane, with applications to other GHGs such as CO₂ and N₂O. The study also highlights the potential for future integration with satellite-based observations, positioning DGGS as a foundational framework for reconciling bottom-up data with top-down measurements in methane emission monitoring. By organizing emissions data within an equal-area DGGS, this work offers a practical, transparent, and computationally efficient model for building next-generation GHG spatially explicit inventory systems.

Project Details

Collaborator(s): Dr. Erin Li and Dr. Steve Liang

Highlights:

Publications:

  • Li, M.E.; Liang, S.H.L. 2025. Enabling a Digital Earth for Methane Emissions Management with Equal-Area Discrete Global Grids. International Journal of Digital Earth. Under review.

Presentations:

  • Standardizing Spatial Intelligence for Gridded Methane Inventories: DGGS Meets EmissionML. Oral presentation at the 132nd OGC Member Meeting - EmissionML DWG, Jun. 2025, Online.
  • Discrete Global Grid Systems (DGGS) and Their Role in Methane Emission Inventories. Presented at the Monthly Lunch and Learn at SensorUp Inc., May 2025, Online.
  • Beyond the Graticule: Spatially Explicit Methane Inventories Using Discrete Global Grids. Oral presentation at the 132nd OGC Member Meeting - Discrete Global Grid Systems DWG, Jun. 2025, Online.
  • Beyond the Graticule: Spatially Explicit Methane Inventories Using Discrete Global Grids. Oral and poster presentation at CanCH4 Symposium, May 2025, Ottawa, Canada. Poster/ Recorded Presentation / Panel Discussion
  • Mapping Methane: A Review of Bottom-up Gridded Inventories. Oral presentation at the 130th OGC Member Meeting - EmissionML DWG ad-hoc, Nov. 2024, Online.

Date: 2024-2025

References

  • Scarpelli, Tia R., Daniel J. Jacob, Michael Moran, Frances Reuland, and Deborah Gordon. 2022. “A Gridded Inventory of Canada’s Anthropogenic Methane Emissions.” Environmental Research Letters 17 (1). doi: 10.1088/1748-9326/ac40b1.