'Big sponge': new CO2 tech taps oceans to tackle global warming

Scientists from University of California Los Angeles (UCLA) have been working for two years on SeaChange -- an ambitious project that could one day boost the amount of CO2, a major greenhouse gas, that can be absorbed by our seas.

Their goal is "to use the ocean as a big sponge," according to Gaurav Sant, director of the university's Institute for Carbon Management (ICM).

The oceans, covering most of the Earth, are already the planet's main carbon sinks, acting as a critical buffer in the climate crisis.

They absorb a quarter of all CO2 emissions, as well as 90 percent of the warming that has occurred in recent decades due to increasing greenhouse gases.

But they are feeling the strain. The ocean is acidifying, and rising temperatures are reducing its absorption capacity.

The UCLA team wants to increase that capacity by using an electrochemical process to remove vast quantities of CO2 already in seawater -- rather like wringing out a sponge to help recover its absorptive power.

"If you can take out the carbon dioxide that is in the oceans, you're essentially renewing their capacity to take additional carbon dioxide from the atmosphere," Sant told AFP.

Trapped

Engineers built a floating mini-factory on a 100-foot (30-meter) long boat which pumps in seawater and subjects it to an electrical charge.

Chemical reactions triggered by electrolysis convert CO2 dissolved in the seawater into a fine white powder containing calcium carbonate -- the compound found in chalk, limestone and oyster or mussel shells.

This powder can be discarded back into the ocean, where it remains in solid form, thereby storing CO2 "very durably... over tens of thousands of years," explained Sant.

Meanwhile, the pumped water returns to the sea, ready to absorb more carbon dioxide from the atmosphere.

Sant and his team are confident the process will not damage the marine environment, although this will require further testing to confirm.

A potential additional benefit of the technology is that it creates hydrogen as a byproduct. As the so-called "green revolution" progresses, the gas could be widely used to power clean cars, trucks and planes in the future.

Then republiCON Marge comes along and stuns experts with her scientifically illiterate rant:

."If you believe that today’s 'climate change' is caused by too much carbon, you have been fooled," she wrote. "We live on a spinning planet that rotates around a much bigger sun along with other planets and heavenly bodies rotating around the sun that all create gravitational pull on one another while our galaxy rotates and travels through the universe. Considering all of that, yes our climate will change, and it’s totally normal!"

Ryan Matoush, a meteorologist at KNST News Topeka, was floored by Greene's total ineptitude at grasping basic scientific concepts.

"It’s absolutely mind boggling to me that someone like this holds a position of power and responsibility - where did we go so wrong??" he asked.

NASA climate scientist Chris Colose sarcastically thanked Greene for debunking his entire work by spouting utter nonsense.

"Good news climate Twitter! We forgot that the Earth spins and revolves so it’s time to pack up and go home," he joked.

QAnon marge is correct however, that the Earth does revolve around the sun, which means she likely does not subscribe to the "flat Earth" conspiracy theory.

Maybe.

Back in reality, A 'Promising solution'

Keeping global warming under control will require the removal of between 450 billion and 1.1 trillion tons of CO2 from the atmosphere by 2100, according to the first global report dedicated to the topic, released in January.

That would require the CDR sector "to grow at a rate of about 30 percent per year over the next 30 years, much like what happened with wind and solar," said one of its authors, Gregory Nemet.

UCLA's SeaChange technology "fits into a category of a promising solution that could be large enough to be climate-relevant," said Nemet, a professor at the University of Wisconsin-Madison.

By sequestering CO2 in mineral form within the ocean, it differs markedly from existing "direct air capture" (DAC) methods, which involve pumping and storing gas underground through a highly complex and expensive process.

A start-up company, Equatic, plans to scale up the UCLA technology and prove its commercial viability, by selling carbon credits to manufacturers wanting to offset their emissions.

In addition to the Los Angeles barge, a similar boat is currently being tested in Singapore.

Sant hopes data from both sites will quickly lead to the construction of far larger plants that are capable of removing "thousands of tons of carbon" each year.

"We expect to start operating these new plants in 18 to 24 months," he said.

© 2023 AFP