Friday, 12 August 2016

The disappearing permafrost

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.' 
Arctic's climate on a cliff-edge

Arctic's climate on a cliff-edge

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. 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.'
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.
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'.
Shoreline on remote island retreats by 74 metres in seven years due to increased wave power of unfrozen sea, and thawing permafrost.

Shoreline on remote island retreats by 74 metres in seven years due to increased wave power of unfrozen sea, and thawing permafrost.
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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