Marine life grows where Antarctic ice collapsed

It had been covered over by ice for many millennia — a sprawling and remote part of the marine world that had remained a science mystery.

So when two massive ice shelves began collapsing in the Antarctic several years ago, an international team of scientists saw a chance to explore a part of the ocean that had never been seen and learn about life at the bottom of the Earth.

The ice shelves were alongside part of the Antarctic Peninsula, an area warming faster than anywhere else on the globe. Many experts feel those collapses are directly tied to human-produced carbon emissions.

"When we were there, we feel so far from the cities where we usually live and we are really in the middle of nowhere," biologist Gauthier Chapelle said of the Census of Antarctic Marine Life expedition, which ended last month. "And then you see that a huge chuck of ice has gone because of our way of life and it shows how everything is intertwined on this planet."

“These kind of collapses are expected to happen more,” he added. “What we’re observing here is probably going to happen elsewhere around Antarctica.”

Traveling aboard a German icebreaker and representing 14 countries, the 50 scientists were keen to see how the environment was being affected by the collapse of the two ice shelves known as Larsen A and Larsen B that had served as a roof over the sea bottom for at least 5,000 years.

Larsen A crumbled 12 years ago, while Larsen B fell apart about five years ago, both unable to remain intact as they floated above the coastal seas.

Melting ice shelves are not expected to directly contribute much to global sea level rise, but glaciologists believe these vast swaths of ice act like dams to slow down glaciers as they move over the Antarctic land mass toward the coast. Without the ice shelves, glaciers may move over the water more quickly, and this would substantially add to rising seas.

Since 1974, 5,213 square miles of ice shelves have disintegrated in the Antarctic Peninsula.

'So much ... to discover'
The Larsen collapses allowed the team to probe a huge portion of the Antarctic using remote operated vehicles, special sounding devices, cameras and two helicopters.

The team discovered a proliferation of life because the area was now exposed to light, allowing a greater diversity of species to take hold and plankton to grow.

Species like sea cucumbers, sea lilies and certain types of sea urchins, which had been previously found only in deep waters, were now showing up in this relatively shallow body of water.

They documented 1,000 species, including:

• An ice fish that has no red blood cells, an adaptation that makes the blood more fluid and easier to pump through the animal’s body, conserving energy at low temperatures;
• Long-limbed sea stars, some with up to 12 arms when five is more typical;
• Groups of sea cucumbers observed moving together, all in one direction;
• Thick settlements of fast-growing animals called sea squirts, which look like gelatinous bags. They apparently started colonizing the area only after the ice shelves collapsed.
  

Among the hundreds of specimens collected, the scientists identified 15 possible new species of shrimp-like amphipods, and four possible new species of cnidarians, organisms related to coral, jellyfish and sea anemones, the scientists said in a statement.

These specimens will be analyzed to determine whether they in fact are newly discovered species.

"What was most striking is that there is so much left for people to discover," said Elaina Jorgensen, a fisheries biologist with the U.S. National Oceanic and Atmospheric Administration who was on the 10-week mission that ended on Jan. 10.

"To see corals at 400 to 600 meters deep that were bright pink and bright purple, it's almost unreal at that depth in really the harshest environment on the planet."

Species boom, but krill a weak link
But the apparent resilience of the area and its species' ability to adapt to new conditions belies a more ominous situation, say team members.

A significant consequence of warming is a gradual decrease of sea ice and of the planktonic algae that grows underneath, noted Michael Stoddart, an Australian researcher who led the expedition.

INTERACTIVE Eyeing the ice Why are climate researchers so interested in Antarctica? The National Science Foundation's Tom Wagner provides an audio tour on what's curious about the continent.

Those algae are food for krill, small shrimp-like creatures that are key to the marine food chain that sustains larger species like whales, penguins and seals. One adult blue whale, for example, eats about 4 million individual krill per day, the researchers said.

“Algae is a source of abundant, high-quality winter food and is utterly central to the health of the whole ecosystem,” said Stoddart.

But recent research by British scientists shows krill stocks decreasing significantly around the Antarctic Peninsula.

Stoddart said the data they've gathered will help monitor future changes in the area and measure the effects of climate change.

"The polar regions are themselves the most vulnerable to climate change," he said. "They are the canaries in the coal mine and keeping an eye on them will give us a good knowledge into the future of the rate of change, so they are crucial areas for us to keep under observation."

In many cases, he said, scientists don't even know what's out there and therefore won't know what they've lost.

"We're beginning to realize that we're destroying the environment before we even know what genetic resources we're getting rid of," he said. "We simply don't know what we have there and if we turn our backs on it and say, well it doesn't matter, then effectively we're mortgaging the future."

MORE FROM CLIMATE CHANGE

Climate Change Section Front

Acidic oceans: Warming's 'evil twin' China blasts claim it 'hijacked' climate talks Once climate central, EU now on outside looking in Climate reality: Voluntary efforts not enough U.N. averts climate collapse by ‘noting’ deal Forest plan got sidelined at climate talks U.S., others broker modest climate deal Climate talks make late progress, but enough? Climate talks look to U.S. for fresh ideas Greater sea level rise likely, study warns Climate Change Section Front   Add Climate Change headlines to your news reader: