Quantifying Methane Emissions from Individual Point Sources with the GHGSat-D Satellite Instrument
Abstract
The GHGSat-D demonstration satellite instrument launched in June 2016 by GHGSat Inc. measures atmospheric methane at fine spatial resolution from backscattered sunlight in the shortwave infrared. Measurements are made at 50-m effective pixel resolution over 12×12 km2 targeted domains, enabling detection and quantification of methane emissions from individual point sources. We demonstrate GHGSat-D point source quantification based on single- and multi-pass plume observations, using a combination of integrated mass enhancement and cross-sectional flux techniques for the source rate retrieval, with error characterization. We present GHGSat-D estimates of instantaneous methane emissions from anomalously large point sources in an oil/gas field, and further demonstrate how our source rate quantification techniques can be adapted for application to time-averaged observations of underground coal mine vents on multiple overpasses. This involves a new application of wind-rotated plume averaging adapted to the small size of the instantaneous methane plumes, where stochastic turbulence has a large influence on individual observations. Our work highlights the key role of large eddy simulations in customizing source rate retrieval algorithms to different measurement conditions.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A53F..03V
- Keywords:
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- 0315 Biosphere/atmosphere interactions;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES;
- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 0428 Carbon cycling;
- BIOGEOSCIENCES