Sea the Difference
In an upcoming episode of ABC's Catalyst, Australian environmentalist and global warming activist Tim Flannery will talk about an unusual idea brewing to fight climate change: seaweed. Featuring Adam Bumpus from the University of Melbourne and colleagues, the episode raises the possibility that these ubiquitous marine plants can help in reducing climate warming gasses.
While the technology to use seaweed to reduce greenhouse gasses remains largely unproven, its potential to do so has already been recognized. For starters, seaweed grows at about 30 to 60 times faster than land-based plants. This means that its ability to absorb carbon dioxide is greater than other plants and makes it ideal for large-scale production.
One possible use is in feeding seaweed or algae to cattle and sheep to reduce their methane emissions. Another involves cultivating giant kelp farms that could make the oceans less acidic, a problem that is growing as the ocean sponges up excess carbon dioxide. Seaweed could even potentially help reduce the huge problem of plastic pollution in the ocean, Bumpus suggests in an article for The Conversation. It could also be potentially easier to maintain than other large-scale plans to combat climate change.
Of course, for the global goal of reducing greenhouse gases and carbon emissions to match the numbers set by the Paris Climate Agreement, a single effort isn't enough. In particular, developing nations like India could potentially add even more carbon emissions, as they bring new power sources online to keep up with booming populations.
Currently, nations all over the world are relying primarily on developing more renewable energy sources: reduced or zero-emissions technologies such as wind power and electric cars, and even building carbon-capture and storage facilities. But this will likely not be enough, as Bumpus writes: "we need an array of solutions, with complementary waves of technology handling different problems."
Adding seaweed into the mix, one study shows, could contribute significantly. For example, using nine percent of the world's oceans to farm seaweed on the surface could remove about 53 billion tonnes of CO2 from the atmosphere every year. Since seaweed is also sturdy, it can store that CO2 in the long term.
Fully harnessing seaweed's potential would take time and effort, however, just as renewables have before becoming a more popular solution. "With further research, development, and commercialization, the possibilities offered by seaweed [...] are potentially game-changing," Bumpus wrote. "We must support the scientists and entrepreneurs exploring zero-carbon innovations – and see if seaweed really can save the world."