How to Measure Methane Emissions in Aquatic Ecosystems

By Audrey Habron

With an atmospheric lifetime of twelve years and its potent ability to trap heat, methane continues to be a significant contributor to climate change. Sources for methane emissions can vary widely, including both natural processes (e.g., wetland emissions, ocean acidification) and human activities (e.g., agriculture, fossil fuels, landfills, hydroelectricity).

Better understanding each methane source and its impact on universal greenhouse gas emissions each year is imperative to devising more effective climate change mitigation strategies; as such, accurate methane measurements and reliable research technology is an integral first step.

Using the Eddy Covariance Technique for Hydroelectric Research

Surprisingly, hydroelectricity is a substantial source of methane emissions; the churning of water through turbines to generate power releases methane into the atmosphere, making this “clean” energy source not as environmentally friendly as originally thought.

A recent BBC article explores this significance and highlights potential ways to research then harness methane for its own energy use. One primary research method is the eddy covariance technique, which can provide precise methane flux measurements as the gas escapes from the water into the atmosphere. Eddy covariance towers are first equipped with a methane analyzer—such as the LI-7700 Open Path CH₄ Analyzer—then fully customized with other gas analyzers, sonic anemometers, biomet sensors, communication devices, solar power supply, and more.

Using Methane Analyzers for Wetlands and Rice Paddy Research

In addition to hydroelectricity, other water-based environments like wetlands are contributing to methane emissions as well. Human activities like agriculture have been a longstanding and well-researched source of greenhouse gases, and rice paddies are considered the largest manmade methane source.

Zutao Ouyang, a postdoctoral researcher at Stanford University, is exploring how rice paddy and wetlands contribute to global emissions. His methane research includes ten eddy covariance flux towers—equipped with LI-COR gas analyzers—that help his team dive deeper into the global carbon budget and devise mitigation strategies.

LI-COR Solutions for Methane Research Applications

In addition to measuring methane in water-based environments, LI-COR methane analyzers have been used in a variety of research applications. From methane emissions in London and at Oktoberfest to long-term and commercial emissions monitoring, the LI-7700 Open Path CH₄ Analyzer and LI-7810 CH₄/CO₂/H₂O Trace Gas Analyzer bring the flexibility and performance that your research needs.

Which methane analyzer is right for your work? Talk to our support team today to find the right fit.