A whole new world: melting ice habitats could cause big changes in the marine realm
The research vessel "Lance" is drifting with the ice north of Svalbard.(Photo: Paul Dodd of the Norwegian Polar Institute)
Imagine travelling along the Arctic sea ice – occasionally dark, deep water peaks from under the vast landscapes of snow-covered ice beneath your feet, as a chilly northern wind turns your breath to vapor. As you walk along, life forms seem scarce.
You may not be able to picture them, but the ice you’re standing on probably embodies thousands of tiny organisms. Some flourish within ice crystal pores and crevices, others attach to the ice underbelly, and more float in the open ocean below.
Worms, crustaceans, bacteria, viruses, algae and diatoms. Some life forms are big enough to spot with the human eye, while other creatures are only visible under a microscope.
But as their habitat quite literally melts away, these ice-dependent species will sink to the depths of the ocean and perish. What could losing these tiny critters mean for the rest of the Arctic marine environment?
Algae on the underside of Arctic sea ice. (Photo: Maria Stenzel)
A whole new world…
An entirely different Arctic marine realm could result.
At least, that’s the working hypothesis for researchers aboard “Lance”, a former seal-hunting boat turned research exploration vessel of the Norwegian Polar Institute. “Lance” sailed from Tromsø on January 15 towards the Arctic ice-cap north of Svalbard.
The ship has been tethered to Arctic sea ice ever since, as researchers collect data day in and day out.
What they’ve found so far is the old, thicker ice which covered the Arctic landscape for years and years is melting away. These days, the region appears to foster thinner, less stable and seasonally melting ice.
“It’s very premature, because right now we’re just collecting data like crazy,” said Dr. Harald Steen, the Lance expedition leader. “But what we do know from our various expeditions and dives over the last few years, is that biodiversity under the thinner ice has drastically gone down.”
What will the future look like?
Dr. Harald Steen, leader of the “Lance” expedition and the Norwegian Polar Institute’s Centre for Ice, Climate and Ecosystems (ICE). (Photo: Thomas Nilsen)
As Arctic waters become warmer, the older, basal layers of ice crystals will melt away, Steen said. “Algae living within icy pores and hanging off the icy platforms will just fall off and sink.”
The small organisms that thrive within Arctic ice are especially vulnerable. Algae under the sea ice have adapted to very cold and low light conditions, Steen said, and can’t easily adapt to changes.
Climate change, combined with the influx of hot Atlantic water, could lead to a unique species distribution, he said.
If the primary productivity changes, then Arctic species that depend on the small species for nutrients and energy further down the food chain will change as well. “Eventually, we will most likely get overrun with southern boreal species that are more suited to the new environment,” he said.
Changes to algae diversity and populations could affect all kinds of species populations down the road, from the famous King crab, to narwhal and beluga. “It’s a working hypothesis at this point,” Steen said, “but it might be a very different Arctic years from now.”
The beluga is a well known Arctic mammal that currently lives under the Arctic sea ice. (Photo: Franco Banfi)
Rough research North of Svalbard
Life further then 80 Degrees North means enduring total darkness for weeks at a time, countless storms and sleeping under frost-covered portholes. Scientists must also be armed with flashlights, headlamps, flare guns and ice claws.
Safety is a priority on board the “Lance,” Steen said.
“As we remind each other when we start expeditions, its not about if you will meet the polar bear, its when,” Steen said.
“We’ve endured polar bears and cold, dark days (usually about -32 degrees Celsius) for months to find the answers to questions about ice, weather and the marine realm,” he said. “Very little data is available already,” he said, “so the research is very important.”