Digesters are systems that cover manure ponds and capture methane to make fuel. Methane is shorter lived than carbon dioxide but it traps heat about 80 times more strongly, so small releases still matter.
A study used eight years of satellite and aircraft observations across California and followed emissions at 98 dairies before, during and after digesters were installed. The researchers found fewer strong methane plumes after installation, which suggests digesters work overall. They also found occasional extreme leaks, sometimes around 1,000 kilograms per hour, and spikes during construction.
The study says satellites and aircraft are useful but should be combined with on-the-ground checks. California is building hundreds of digesters, and researchers call for careful monitoring to keep the climate benefits real.
Difficult words
- digester — machine that captures gas from farm wasteDigesters
- methane — a gas from organic matter that traps heat
- plume — a visible column or cloud of gasplumes
- emission — gas or pollutant released into the airemissions
- leak — an unwanted escape of gas or fluidleaks
- monitor — to check or watch something over timemonitoring
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think digesters are a good idea to reduce methane? Why or why not?
- What problems did the study find with some digesters?
- Why should satellites and aircraft be combined with on-the-ground checks?
Related articles
Rwanda strengthens response to Rift Valley Fever outbreak
Rwanda reported a second Rift Valley Fever outbreak near the Tanzania border and has increased surveillance and livestock vaccination. Officials say lack of rapid diagnostic tests slows detection, while a human vaccine candidate enters Phase II trials.