Track­ing re­treat of Arc­tic ice high­lights cli­mate change

The China Post - - LIFE GUIDE POST - BY CILINE SERRAT

Not so long ago, skele­ton staff win­ter­ing at the Ny-Ale­sund re­search cen­ter could walk on the Arc­tic town’s frozen bay and race their snow mo­biles across its sur­face.

Now there is liq­uid wa­ter even in the cold­est months, the glaciers are re­treat­ing at a rate of hun­dreds of me­ters per year, and alien species from warmer climes are mak­ing the bay their home, say long­time res­i­dents of the sparsely pop­u­lated town on the Nor­we­gian is­land of Spits­ber­gen.

“In the 1990s, we could cross the bay in snow mo­biles,” re­called Juer­gen Graeser, a tech­ni­cian at the Franco- Ger­man Awipev re­search sta­tion which col­lects weather, at­mo­spheric and chem­i­cal data.

“The last time we could walk on it was in the win­ter of 2003-04.”

And since 2007, the Kongs­fjor­den fjord or bay that carves into the is­land’s west coast, “has not frozen over once,” said Se­bastien Bar­rault, a re­search ad­viser for the Kings Bay lo­gis­tics com­pany.

These days, the bay in win­ter more closely re­sem­bles its sum­mery self: a vast ex­panse of wa­ter dot­ted with ice­bergs and patches of ice sheet, framed by glaciers.

Just 1,000 kilo­me­ters ( 621 miles) south of the North Pole, the is­land’s cli­mate was al­ways mild for its high lat­i­tude (26 de­grees Cel­sius) due to a warm ocean cur­rent that runs along its west coast.

But the Arc­tic has warmed more than any other re­gion on Earth — a phe­nom­e­non some sci­en­tists have linked to feed­back from sea ice loss and changes in at­mo­spheric and ocean cir­cu­la­tion caused by over­all planet warm­ing.

The re­gion has warmed about 1.0 to 1.2 de­grees Cel­sius in each of the past two decades — far ex­ceed­ing the global 0.8 Cel­sius av­er­age since the pre-in­dus­trial era.

In March, U.S. of­fi­cials said Arc­tic sea ice had reached its low­est win­ter point since satel­lite ob­ser­va­tions be­gan in the late 1970s — rais­ing con­cerns for sea level rise and the sur­vival of po­lar bears and marine crea­tures which de­pend on the ice.

The shrink­ing of sun­light-re­flect­ing ice sheets and glaciers, in turn, leads to more heat be­ing ab­sorbed by land and sea.

Mack­erel? In the Arc­tic?

Ny-Ale­sund, the world’s north­ern­most per­ma­nent hu­man set­tle­ment, is caught up in the trans­for­ma­tion and of­fers the per­fect van­tage point for sci­en­tists study­ing the rate and ef­fects of global warm­ing.

Oceanog­ra­pher Philippe Ker­herve has come to the erst­while coal min­ing vil­lage to study sed­i­ment trans­porta­tion by glaciers — com­pressed masses of ice and rock that “flow” slowly over land.

Glaciers cover about 60 per­cent of Spits­ber­gen. One of the big­gest among them, Krone­breen, sports a mas­sive two kilo­me­ter-wide crack in its fa­cade, and has re­ceded by a kilo­me­ter since 2012.

Glacier flow usu­ally is faster in the sum­mer months, when ice melts into wa­ter, sweep­ing up crushed rock and mud be­tween the glacier and the land sur­face, and dump­ing it into the bay.

But the flows are get­ting stronger.

“With global warm­ing, there is more melt and more rocky sed­i­ment. It is the rich marine ecosys­tem of the fjords that will be more and more af­fected,” said Ker­herve.

Species through­out the food chain, ev­ery­thing from krill and sea­weed, shell fish, fish and mam­mals like seals, may suf­fer from too much mud be­ing dumped into the bay that pro­vides their food, shel­ter and breed­ing grounds.

Add to this com­pe­ti­tion from new species ar­riv­ing in the area, pos­si­bly aided by cli­mate changein­duced sea cur­rent changes.

“We are now see­ing species that are not nor­mally found in the Arc­tic,” said Bar­rault, star­ing out over Kongs­fjor­den.

“The At­lantic cod now travel all the way here, and we are start­ing to see mack­erel,” he said.

Bar­na­cle geese which em­i­grate ev­ery year from Scot­land, have since 2007 “sud­denly ad­vanced their mi­gra­tion by 15 days,” said or­nithol­o­gist Maarten Loo­nen.

“They are adapt­ing to the ear­lier ar­rival of spring here.”

U.N. cli­mate talks are meant to de­liver a global pact in Paris by yearend to peg av­er­age global warm­ing to 2 de­grees Cel­sius, the level at which sci­en­tists be­lieve we may avoid the worst cli­mate im­pacts.

But they warn that at cur­rent rates, the world is head­ing for dou­ble that rate, or more.

2. French oceanog­ra­pher Philippe Ker­herve takes sam­ples from the Kongs­fjor­den fjord near the sci­en­tific base of Ny-Ale­sund on July 21. 3. A pic­ture taken on July 22 shows a man en­ter­ing a Chi­nese base at the sci­en­tific base of Ny-Ale­sund. 4. A pic­ture taken on July 21 shows a for­mer mine at the sci­en­tific base of NyAle­sund.

AFP

1. This aerial view taken on July 20 shows the Krone­breen glacier with red traces of sed­i­ments near the sci­en­tific base of Ny-Ale­sund, in the Sval­bard ar­chi­pel­ago of Nor­way.

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