For
those New Zealanders who are insular enough to think that only local
news is relevent (lik Radio NZ) this should be frightening.
I
can see the spin when it happens – a “wonderful” spectacle and
there will be tourist trips to see the iceberg.
The
Larsen C Iceberg Is on the Brink of Breaking Off
The
saga of the Larsen C crack is about reach its stunning
conclusion.
31
May, 2017
Scientists
have watched a rift grow along one of Antarctica’s ice shelves for
years. Now it’s in the final days of cutting off a piece of ice
that will be one of the largest icebergs ever recorded.
It’s
the latest dreary news from the icy underbelly of the planet, which
has seen warm air and water reshape the landscape in profound ways.
The
crack has spread 17 miles over the past six days, marking the biggest
leap since January. It’s also turned toward where the ice shelf
ends and is within eight miles of making a clean break. There’s not
much standing in its way either.
“The
rift has now fully breached the zone of soft ‘suture’ ice
originating at the Cole Peninsula and there appears to be very little
to prevent the iceberg from breaking away completely,” scientists
monitoring the ice with Project MIDASwrote
on their blog.
The
growth follows reports from early May that the crack across the ice
shelf had sprouted a branch, further underscoring how unstable the
ice is becoming. Ice shelves float over water and essentially act as
doorstops that hold back the vast Antarctic ice sheet.
The
breakup is sure to be a spectacle both awe-inducing and horrifying.
The iceberg on the verge of splitting off is estimated to be the size
of Delaware, covering an area of 1,930 square miles. That’s equal
to 10 percent of the ice shelf’s total area.
Once
it breaks off, scientists are concerned that the rest of ice shelf
could collapse afterwards, a fate that befell Larsen A in 1995 and
Larsen B in 2002. In Larsen B’s case, the ice shelf collapsed in
the span of a month following an influx of mild air.
In
February, the New
York Times reported that
when the iceberg breaks off, it will weaken or destroy two key areas
where ice overlaps islands. Those areas help keep the ice shelf from
falling apart. Losing them could dramatically reduce the remaining
ice shelf’s stability. Larsen C is substantially larger than its
former neighbors Larsen A and B, and its loss would be a huge blow to
ice on the Antarctic Peninsula.
he changes don’t just stop with the Larsen C crack or the Antarctic Peninsula in general. The vast majority of ice shelves are losing volume due to rising ocean and air temperatures. That’s helped prime parts of West Antarctica for what might be unstoppable melt that could raise sea levels at least 10 feet.
Researchers
also recently found meltwater ponds are much more common than
previously thought. They even discovered a roaring
seasonal waterfall on
the Nansen Ice Shelf.
These
and other findings make clear that the Larsen C crack is just one
of many
changes happening to
Antarctica. Global warming has pushed temperatures up to 5°F higher
in the region since the 1950s and they could increase up to 7°F
further by the end of the century, putting more stress on ice.
Though
the changes are happening in the most remote part of the planet,
they’re being felt thousands of miles away as ice turns to water
and starts to lap against increasingly
beleaguered coastal communities around
the world. And the impacts will only grow more severe unless carbon
pollution is reined in.
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