Scientists have found red seaweed 100 metres deep in Antarctica and believe their find could help play a role in the battle against climate change.
The researchers hoped to understand how deep down seaweed in Antarctica could survive – and used a robot craft to find seaweed attached to rocks.
Finding the red alga Palmaria decipiens deep underwater is key in our understanding of Antarctica, "a continent that is so important to understand for addressing the environmental challenges the world faces today", the scientists said.
A team working at the Rothera Research Station on Adelaide Island, off the south-western Antarctic Peninsula, made the discovery
Professor Frithjof Kuepper, of the School of Biological Sciences at the University of Aberdeen, described the "huge role" seaweeds can play in protecting the environment.
He said: "We know that carbon capture will be crucial to limiting global warming as we move forward, and seaweeds sequester large amounts of CO2 [carbon dioxide].
"Seaweeds have the potential to play a huge role in protecting the environment by storing carbon at the bottom of oceans when they die and reducing ocean acidification.
"Seaweeds are also an important food source to numerous animals and fish and have been eaten by people in many coastal communities in parts of the world for centuries... [and] have been used in a variety of cosmetic and pharmaceutical goods and with carbon-neutralising properties it represents a sustainable product."
Using a remotely operated vehicle (ROV) from a small boat, the researchers successfully collected seaweed samples for further examination.
They had set out to clarify the maximum depths that seaweed could grow in Antarctica.
Kuepper said: "We now know that seaweeds can live at least down to 100 metres depth in Antarctica. That is quite a lot, but we can't rule out that they may live even deeper."
Ben Robinson, of the British Antarctic Survey and University of Southampton, added: "In Antarctica, icebergs scour and remove seaweed from the shallows, leading to lots of loose seaweed at depths where it is no longer attached to the seafloor.
"Due to cold temperatures, it can take many years for these loose seaweeds to even start breaking down, so we could not rely on appearance.
"Instead, we needed to use an ROV to test and collect seaweed to confirm whether they were attached to the seafloor and to confirm a new depth limit for seaweed."
Watch: Climate change is disrupting how we date and mate