Publications by authors named "G P Asner"

Airborne remote sensing observations were collected at 217 landfills across 17 states in the US in 2023. We used these observations to attribute emissions to major sources, including the landfill work face, where new waste is placed at the landfill and gas-control infrastructure. Methane emissions from the work face appeared to be more prevalent than gas-control infrastructure emissions, with 52 landfills exhibiting work face emissions out of the 115 observed landfills shown to be emitting in 2023.

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Article Synopsis
  • Combining data from different satellite sensors is crucial for accurately understanding methane emission trends and uncertainties, but this requires a thorough characterization of the probability of detection (POD), which can be expensive and time-consuming.
  • Recent aerial surveys in August 2023 aimed to synchronize with NASA's EMIT observations to assess detection limits and to create a framework for combining multiple sensors, highlighting the importance of accurate POD assessment to avoid underestimating emissions from persistent sources.
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Methane emissions from solid waste may represent a substantial fraction of the global anthropogenic budget, but few comprehensive studies exist to assess inventory assumptions. We quantified emissions at hundreds of large landfills across 18 states in the United States between 2016 and 2022 using airborne imaging spectrometers. Spanning 20% of open United States landfills, this represents the most systematic measurement-based study of methane point sources of the waste sector.

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Coral reefs are in decline worldwide, making it increasingly important to promote coral recruitment in new or degraded habitat. Coral reef morphology-the structural form of reef substrate-affects many aspects of reef function, yet the effect of reef morphology on coral recruitment is not well understood. We used structure-from-motion photogrammetry and airborne remote sensing to measure reef morphology (rugosity, curvature, slope, and fractal dimension) across a broad continuum of spatial scales and evaluated the effect of morphology on coral recruitment in three broadcast-spawning genera.

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Coral reef ecosystems are being fundamentally restructured by local human impacts and climate-driven marine heatwaves that trigger mass coral bleaching and mortality. Reducing local impacts can increase reef resistance to and recovery from bleaching. However, resource managers lack clear advice on targeted actions that best support coral reefs under climate change and sector-based governance means most land- and sea-based management efforts remain siloed.

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