truncated ice shelf will react to this change by flowing faster
into the ocean, which will also lead to more calving.
To improve those simulations, Luckman says, scientists need
to directly measure changes in the ice shelf, particularly while
it is still in its initial response phase. In November, a team led
by the University of Leeds in England was the first to journey to
the peninsula. To map out subsurface structures in the ice, the
team conducted geophysical surveys, including using ground-penetrating radar, on the still-intact part of the ice shelf. Using
GPS, the researchers also monitored the shelf’s movements.
Another team of scientists, led by marine biologist Katrin
Linse of the British Antarctic Survey in Cambridge, is preparing for a separate voyage to the ice shelf in February. Linse and
colleagues’ mission is to learn what was living on the seafloor
in the shadow of the ice. What creatures might inhabit that
region is a bit of a mystery. Linse says she expects to find something similar to ecosystems found in the deep sea — a dark,
extremely food-sparse environment with no plant life. Such
environments can spawn odd creatures, such as carnivorous
sponges and bivalves that snatch at the tiniest food sources.
It’s also possible that the team will find nothing alive, she says.
Meanwhile, the Larsen C iceberg is still in the picture and
could present a navigational headache. As of November, the
southern edge of the berg was about 25 to 30 kilometers from
the shelf, offering a research ship some wiggle room to examine the seafloor, Linse says. But the northern edge was still just
two kilometers away, a gap too close for comfort.
The researchers may have little time to examine that ecosystem before it begins to change. Now that sunlight can penetrate
the waters, microalgae will quickly begin to grow, providing an
abundant food source to any seafloor denizens — and an enticement to new colonizers. In one to three years, species such as
krill may become abundant. After several more years or even
decades, there may be enough food to support penguins, seals
Scientists have previously documented a recently exposed
Antarctic seafloor ecosystem only after it was already in transition. In 2007, marine ecologist Julian Gutt of the Alfred
Wegener Institute led a trip to the Larsen B ice shelf to study the
seafloor that had emerged from its ice shadow five years earlier.
The researchers found strange new species but also discovered
pioneering critters that had already moved in ( SN: 9/7/13, p. 11 ).
Gutt plans to return to the region in 2019. That expedition
originally planned to map the seafloor along the Antarctic
Peninsula, but will now include time to study the biodiver-
sity of the seafloor at Larsen C, plus return to Larsen B. “Each
species occurring under the former ice shelf would be inter-
esting,” Gutt says. “How can they survive under such unusual
Whatever is found, Linse says she will consider her mission a
success: “If no communities could thrive, that would be a very
interesting result because I expect to find life there.”
Even though the Larsen C ice shelf irreversibly broke in
2017, the discoveries are just beginning. s
ly 7 million