Australia's CSIRO has identified a strain of seaweed that can reduce bovine methane emissions by more than 99 percent if added to cow feed in small amounts. This could be huge for climate change, but it also has significant benefits for farmers.

I thought this was a cow fart story; it's not. Sadly, according to Australia's CSIRO, the vast majority of bovine methane – some 90 percent of all emissions – comes from burps, not from backdraft.

But whichever end it comes from, methane represents a problem. In climate change terms, methane is a greenhouse gas 28 times more powerful than carbon dioxide. In agricultural terms, when cows burp out methane, as much as 15 percent of the energy in their feedstock is being thrown away instead of converted into meat.

For more than a decade, researchers have been aware that adding seaweed to a cow's diet made a significant reduction to that methane release, leading to cleaner agriculture and better meat production. Early tests found seaweed could cut back methane release by as much as 20 percent.

But recently, Australian scientists have been re-running tests with a variety of different species of seaweed to find out which is the most effective, and now, a very clear winner has emerged.

David Fuller's view

This has the potential to be a very important discovery.  Clearly the challenge of growing and harvesting many thousands of hectares of a particular type of seaweed known as Asparagopsis taxiformis sounds daunting, controversial and expensive.  Nevertheless, assuming biochemists can identify and recreate the key ingredients for methane reduction, they should be able to reproduce them much more efficiently.