Direct measurement of plume velocity to characterize point source emissions

• 成果类型: Article
• 署名作者: Eastwood, Michael L.; Thompson, David R.; Green, Robert O.; Fahlen, Jay E.; Adams, Taylor J.; Brandt, Adam R.; Brodrick, Philip G.; Chlus, Adam; Kort, Eric A.; Reuland, Frances; Thorpe, Andrew K.
• 署名单位: California Institute of Technology; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); University of Michigan System; University of Michigan; Stanford University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12866
• DOI: 10.1073/pnas.2507350122
• 发表日期: 2025-09-09
• 关键词: satellite-observations; quantifying methane; scale

摘要

An explosion of recent research uses remote imaging spectroscopy from aircraft and spacecraft to detect and quantify methane point source emissions. These instruments first map the methane enhancement field and then combine this information with the effective wind speed to estimate the source emission rate. This wind speed is typically the largest uncertainty in derived emission rates. It is often, by necessity, inferred from coarse-resolution meteorological reanalysis products which do not match the spatial or temporal extent of wind experienced by the gas plume. Here, we circumvent this problem by simultaneously measuring plume velocity using the same spectrometer that maps the methane plume. Our approach acquires multiple consecutive views of the same point source, with visual tracking of the plume's features to estimate its ground velocity. This resolves the representational mismatch between reanalysis and effective wind speeds. It provides data with exact spatiotemporal coincidence to the plume being measured. The approach facilitates dramatic improvement in the precision of remote methane point source quantification.