Chinese researchers develop satellite-based method to quantify global landfill methane emissions

BEIJING, July 31 (Xinhua) -- Chinese researchers have achieved a breakthrough in monitoring methane emissions from landfills, paving the way for more effective global emission reduction strategies. The study was published on Monday in the journal Nature Climate Change.

A team from the Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences has pioneered an innovative approach using high-resolution satellite remote sensing to accurately quantify landfill methane emissions -- and also conducted a systematic assessment of global landfills using this approach.

"Satellite remote sensing enables uniform global quantification of landfill methane emissions with higher spatiotemporal resolution than traditional methods," said AIR researcher Cheng Tianhai. "This approach enhances monitoring accuracy and coverage while offering new solutions for global methane emissions tracking."

As the third-largest anthropogenic methane source, accounting for 18 percent of human-related emissions, landfills require precise monitoring. Current methods, which rely on ground measurements and model estimations, face limitations in terms of coverage, accuracy and cost.

The AIR team employed 30-meter spatial resolution and 10-nanometer spectral resolution, combined with a matched-filter algorithm and an integrated mass enhancement technique, to identify and quantify methane plumes, a feather-like diffusion structure formed after gas is released from emission sources, and their emission rates from 102 landfills worldwide. They detected 367 valid plumes -- achieving precise global emission measurements.

"This marks the first global-scale systematic evaluation of methane emission differences under various landfill management practices," said Tong Haoran, the first author of the paper. "The study provides a scientific basis for correcting current emission database biases." ■