Huge rafts of a large brown seaweed called kelp have found their way to the cold, icy shores of Antarctica after traveling thousands of miles from warmer waters.
Researchers at the Australian National University in Canberra believe this is the first piece of evidence that Antarctica is not as isolated from the rest of the Earth as it was previously thought.
The discovery brings new insight into how experts understand how Antarctica's current condition will change in the future and how climate change comes into play.
Impenetrable Antarctica
For years, experts have believed that Antarctica was home to plant and animal species distinct from other species in the world because of its isolation.
However, the latest findings show that the differences in flora and fauna were brought about more by the extreme environmental conditions in the south pole than anything else.
In a new study published in the journal Nature Climate Change, the Australian team of researchers says the rafts of kelp floated more than 12,000 miles to settle on Antarctica's icy beach.
The journey was once thought to be impossible because of the powerful polar winds and surface currents that create a seemingly impenetrable barrier around the continent.
An analysis of the seaweed specimens, however, show that some of the kelp drifted all the way from the Kerguelen Islands in the southern Indian Ocean and South Georgia in the southern Atlantic Ocean.
"This is an unequivocal demonstration that marine species from the north can reach Antarctica," says lead author Crid Fraser of the ANU Fenner School of Environment and Society.
Antarctic Storms Come Into Play
The 12,000-mile journey is currently the largest known instance of oceanic dispersal of biological matter, according to the researchers.
It is likely that the kelp arrived in Antarctica on the back of giant waves churned into being by southern storms.
"To get there, the kelp had to pass through barriers created by the polar winds and currents that were, until now, thought to be impenetrable," explains Fraser.
The findings of the study upend everything experts understand about oceanic dispersal in the South Pole.
The prevailing theory was that the strong Antarctic winds and surface currents push all objects away to the north. However, computer modeling done by co-researcher Adele Morrison of the Australia Research Council's Centre of Excellence for Climate Extremes shows this is not the case.
When storms are included in the equation, the impenetrable barrier theory crumbles to pieces. The modeling shows how large waves generated by storms were able to help the rafts reach Antarctica.
"Once we incorporated wave-driven surface motion, which is especially pronounced during storms, suddenly some of these biological rafts were able to fetch up on the Antarctic coastline," says Morrison.
Implications For Climate Change
Marine biologist Erasmo Macaya of the Universidad de Concepción in Chile found the kelp washed up on the shores of Antarctica.
He says the huge clumps of seaweed can act as biological rafts for smaller marine life to latch onto as the kelp travels to the southern regions.
This has huge implications for climate change, since plants and animals drifting to Antarctica from other places can easily establish themselves once the climate in the south pole becomes warmer and more favorable to other forms of life.
The new research will also be useful in other fields, such as in tracking down plastic garbage dumped into the ocean and debris from airplane crashes.
