Arctic's climate on a cliff-edge
Shoreline
on remote island retreats by 74 metres in seven years due to
increased wave power of unfrozen sea, and thawing permafrost.
By Olga
Gertcyk
10
August 2016
The
rapid changes leading to this house being on the cliff edge are seen
as being caused by a marked speeding of erosion of the permafrost
shore by waves. Picture: Ivan Mizin/WWF Russia
The
stunning speed of the coastal erosion on Wiese Island in the northern
Kara Sea - shown here - is a graphic example of the impact of warming
temperatures in the Siberian Arctic. Ironically, the collapsing
building is a disused Soviet meteorological station that now stands
on the brink due to changes in the weather.
Our
main pictures shows it about to collapse into the frozen sea last
winter. It may already have done so this summer.
Seven
years ago it stood some 74 metres from the sea. When it was built in
1945, it was much further away.
Glaciologist
Dr Alexander Aleinikov compared the coastline on the island - also
called Vize Island - between 2009 and this year.
'The
shores of the Wiese Island were collapsing earlier too,' he said. 'It
is a natural process. However, if back in the 1950s polar experts
reported (a retreat of) about 1.5 metres per year, according to
satellite images taken from 2009 to 2016, the shore has stepped back
by 74 metres at this place.
'The
speed has increased significantly.'
Shoreline on remote island retreats by 74 metres in seven years due to increased wave power of unfrozen sea, and thawing permafrost. Pictures: Ivan Mizin/WWF Russia, Aleksandr Aleinikov/WWF Russia
Oksana
Lipka, coordinator of WWF's climate and energy programme, said: 'It
was earlier believed that the fastest pace of shore erosion in Russia
and the world was in the Novosibirsk Islands (between the Laptec and
East Siberian seas) that 'step back' by 5-to-15 metres a year,
sometimes by 20 metres after a strong storm.
'It
is likely that the pace of shore erosion is even higher (on Wiese
Island). We've got to conitue monitoring."
The
rapid changes leading to this house being on the cliff edge are seen
as being caused by a marked speeding of erosion of the permafrost
shore by waves.
Previously,
the sea was frozen for a much longer period during the year, so the
waves had limited power in battering the coast. The melting of
the sea ice means the coastal permafrost, weakened by warmer
temperatures, faces more forceful waves.
The
energy of wave impact directly depends on number of summer days when
there is so-called open water around the island - without ice.
Analysis
of Landsat satellite images over recent years shows the open water
period increased because of global warming.
For
example, a satellite image taken on 15 July 2016 shows there is
absolutely no ice in the water area around the island.
The
increase in temperature of the air and the sea's surface, along with
the reduction of ice and extension of the time the water is
'open' are the consequences 'of climate change in northern
latitudes', says WWF.
'Remarkably,
the temperature in the Arctic is rising twice as fast as anywhere on
the planet. This allows new opportunities for exploring the Arctic.'
Wiese Island in the Kara Sea marked on the world map. Picture: The Siberian Times
Dr
Ivan Mizin, senior expert at the WWF's Barents Sea office, said: 'Sea
islands that are altering both because of human influence and climate
change require careful attention of researchers.'
He
warned: 'Wiese Island needs protection first of all as a year-round
habitat of Polar bears, Atlantic walruses, and Ivory gulls. It
is located on the border of two seas and joins the population of
these rare species.
'We
need to understand if reduction of the size of the island will affect
these species and to what extent.
'To
do that, it is desirable to limit human impact to the already
existing Polar meteorological station and obtain reserve status (for
the island).'
With
an expected large increase in commercial shipping using the Northern
Sea Route between Asia and Europe - along the Russian coastline - he
said it was important to 'preserve the most precious natural
territories that will play an important role in maintaining
biological diversity of the Kara sea during its commercial
exploration'.
Icebreakers on the Northern Sea Route. Picture: Slava Titov
The
desolate island, subject to severe storms, is part of Krasnoyarsk
region and is located in the Arctic Ocean at the northern end of the
Kara Sea, roughly midway between Franz Josef Land and Severnaya
Zemlya. In 1924, oceanographer Vladimir Wiese predicted the
island's existence before it was known as a fact.
He
studied a deviation in the drift of Georgy Brusilov's ill-fated
Russian ship Svyataya Anna which was trapped on the pack ice of the
Kara Sea.
The
island was discovered on 13 August 1930 by a Soviet expedition led by
Otto Schmidt aboard the Icebreaker Sedov.
Professor
Wiese, of the Soviet Arctic Institute, was on board the Sedov and set
foot on the island whose existence he had predicted.
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