A team of scientists has theorized that nanoparticles from melting glaciers can help slow global warming, by trapping CO2 from the atmosphere.
According to a report in New Scientist, Rob Raiswell of the University of Leeds, UK and colleagues trained high-resolution microscopes on ice sampled from icebergs in the Southern Ocean and the Antarctic glaciers from which they are born.
They found nano-sized particles of iron, between five and 10 millionths of a millimetre across.
The team believes that because of the size and structure of the particles, the iron could be assimilated by phytoplankton.
"Most of the ground-up rock carried by icebergs is thought to be inert," said Raiswell. "However, the high resolution microscopy shows there are small amounts of iron nanoparticles. They simply could not be seen except by these techniques," he added.
Phytoplankton need iron in order to grow, and the Southern Ocean is generally thought to be low on iron.
But, there is evidence that some Antarctic glaciers are flowing into the ocean faster because of climate change, which is evidence of more icebergs.
If Raiswell's findings are correct, more icebergs would mean more dissolved iron, therefore more phytoplankton, and more carbon dioxide sucked out of the atmosphere and into the oceans.
"Dust has been thought to be the main outside source of iron to the Southern Ocean," said Raiswell.
He and his colleagues calculated that existing icebergs could double the supply of iron to the region.
Now, the researchers will need to prove that the nano-iron can indeed boost plankton growth.