A volunteer picking up plastic on an Italian beach

[Beauty Sirikarn]

Prof Jambeck's 2015 study provides a global estimate on the "mass of land-based plastic entering the ocean".

And the other study is an estimate of the amount of straws on coastlines around the world.

It appears a calculation has been done using these findings.

The 0.03% figure was also referenced in a Bloomberg Opinion piece in 2018.

This is very much an estimate, and Prof Jambeck said no-one really knows how much of it is straws, but experts agree that it is certainly a lot less than dumped fishing gear.
Prof Hardesty does not think that straws are a bigger issue than lost fishing gear, but the risks posed by nets are clearly a major issue.

"Abandoned, lost, derelict fishing gear poses substantial environmental harm to coastal and marine species," she says, "and we know far more about entanglement risk than we do about ingestion risk (of other objects) to wildlife".

Claim: Micro-organisms absorb four times more CO2 than the Amazon
This claim is about the important role the oceans play combating global warming.

Microscopic organisms in the ocean called phytoplankton absorb carbon dioxide and release oxygen, just like plants.

The documentary refers to an IMF report that says "we calculate that this is equivalent to the amount of carbon dioxide (CO2) captured by 1.70 trillion trees - four Amazon forests' worth".

Experts say that the figure is about right, and could even be an under-estimate.
"It's fair to say that over the global ocean, phytoplankton absorb about four times as much carbon dioxide as the Amazon does," says Dr BB Cael, a scientist at National Oceanography Centre in Southampton.

And Dr Cael says oceans can store carbon for a long time.

"A portion of the carbon absorbed by phytoplankton sinks into the deep, and stays there for hundreds to thousands of years until the ocean slowly brings it back up to the surface.

"A much smaller amount of the carbon taken up by trees is sequestered from the atmosphere for that long," says Dr Cael.

Recent research has also shown that some type of phytoplankton are better at absorbing carbon than others.

A 2020 study examined the annual appearance of phytoplankton - the spring bloom - and found that large ones, which are the most effective at taking in CO2, were far less common than previously believed.

"This will definitely impact the model of carbon flows," said Oregon State University microbiologist Steve Giovannoni.

Another study published in 2020 looked into what's called the "biological pump" - when plankton die they fall to the deep ocean, removing carbon from the surface and storing it. pg slot

"If the deep oceans didn't store so much carbon, the Earth would be even warmer than it is today," wrote its author Ken Buesseler.

"We estimate that the biological pump carries twice as much heat-trapping carbon down from the surface ocean than previously thought," said Mr Buesseler.
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Beauty Sirikarn