Giant green Antarctic algae visible from space
A field of vivid green algae so large it can be seen from space is floating in waters off Antarctica, causing a feeding frenzy.
Images of the bloom, estimated to be around 200 kilometres wide and 100 kilometres long, were captured by Australian scientists monitoring a satellite 650 kilometres above the Earth.
Scientist from the Australian Antarctic Division say they are still not sure exactly what caused the bloom but they predict it will be causing a stir among the local wildlife.
Research scientist Mark Curran says much of the food chain will be benefiting from the algae.
“You might expect more animal behaviour in this region as a result of predators chasing the smaller species that feed on off this kind of algae,” he said.
“[There’s] krill and other zoo plankton and then of course you’ve got the penguins, the seals and whales that will feed on the fish or the krill itself.”
Dr Curran says the green growth is thought to be phaeocystis algae and one theory behind its existence is an increase in iron levels.
He says Antarctica experienced strong winds over summer that may have blown snow off the frozen continent and into the ocean.
He says there are small levels of iron in Antarctica’s snow.
“Very, very tiny amounts of iron act as a nutrient. Usually algae in this region are iron limited and so when they get a small amount of iron and they have everything else they need, that’s enough for them to bloom,” he said.
The algae has been floating around for the past 20 days and was visible from space as late as Sunday.
Dr Curran says it could hang around for a while yet, but will eventually disperse naturally.
“They die off, things like bacteria comes through there and feeds on the material and then the material eventually will sink to the bottom of the ocean – anything that hasn’t been consumed by predators higher up the food chain,” he said.
But it is hoped that is not before the research vessel Aurora Australis travels through the region.
The ship recently left Mawson Station, west of where the bloom is floating, and is likely to travel through the area shortly.
Dr Curran says it is hoped the Aurora Australis will be able to collect water samples from the area to bring home so scientists can try and identify it.
He says the bloom is a natural event and unlikely to negatively impact the environment.