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Home → June, 2014

Monthly Archives: June 2014 − News & Stories


Quant­ar­c­ti­ca: free GIS to make ant­ar­c­tic rese­arch data acces­si­ble for all

Sci­en­tists are con­stant­ly gathe­ring lar­ge amounts of data in and about Ant­ar­c­ti­ca. But how can the public access and use the­se data? The Nor­we­gi­an Polar Insti­tue has made an effort to make sci­en­ti­fic data from Ant­ar­c­ti­ca acces­si­ble for ever­y­bo­dy by publi­shing Quant­ar­c­ti­ca” title=”Quantarctica” target=”_blank”>Quantarctica, a free open source GIS (geo­gra­phic infor­ma­ti­on sys­tem) to com­pi­le ant­ar­c­tic sci­en­ti­fic data. The sys­tem is based on Quan­tum GIS and has data within ocea­no­gra­phy, atmo­sphe­ric sci­ence, geo­lo­gy and bio­lo­gy.

As soon as the soft­ware is instal­led, it is pos­si­ble to use Quant­ar­c­ti­ca off­line.

Sci­en­ti­fic users can also upload their data to publish them quick­ly to a wide public.

Quant­ar­c­ti­ca (Screen­shot): free open source GIS with sci­en­ti­fic data from various rese­arch bran­ches in Ant­ar­c­ti­ca.

Quantarctica (Screenshot)

Source: Quant­ar­c­ti­ca

Vol­ca­nic acti­vi­ty under Thwai­tes Gla­cier con­tri­bu­tes to mel­ting

The Thwai­tes Gla­cier in West Ant­ar­c­ti­ca has recent­ly attrac­ted con­sidera­ble media atten­ti­on, as sci­en­tists have pre­dict it to col­laps lar­ge­ly in the future. It is up to 4 kilo­me­t­res thick and lar­ge enough to con­tri­bu­te with 1-2 met­res to glo­bal sea level rise – a dra­ma­tic value. So far, warm sea water has been made respon­si­ble for gla­cier mel­ting on the coast, but now the­re is evi­dence that a signi­fi­cant part of mel­ting actual­ly takes place at the gla­cier base, away from the coast. Thwai­tes Gla­cier is lar­ge­ly based well below sea level, as is the case for lar­ge parts of the West Ant­ar­c­tic ice shield, a fact that con­tri­bu­tes to its lack of sta­bi­li­ty.

Timing and dura­ti­on of a col­laps are, howe­ver, curr­ent­ly unknown, even though it seems wide­ly accept­ed among­st sci­en­tists that a col­laps is very likely. But one of the main influen­ces on gla­cier dyna­mics were so far unknown: the geo­ther­mal heat flux from the under­ly­ing crust to the gla­cier ice. Until now, it has been belie­ved that geo­ther­mal heat trans­fer is even­ly dis­tri­bu­ted over the area of the under­ly­ing crust.

Sci­en­tists of the Insti­tu­te for Geo­phy­sics of the Uni­ver­si­ty of Texas at Aus­tin have now reve­a­led that this is any­thing but the case. Sub­g­la­cial melt­wa­ter move­ment under the Thwai­tes Gla­cier was map­ped with radar-based methods. The result is that melt­wa­ter pro­duc­tion is very uneven­ly dis­tri­bu­ted. This can be used to cal­cu­la­te the geo­ther­mal heat flux under the gla­cier, which rea­ches values up to 200 mil­li­watts per squa­re met­re while aver­aging near 100 over the who­le area. In com­pa­ri­son, the avera­ge value for all con­ti­nents on Earth is just near 65 mil­li­watts per squa­re met­re.

The­se values of geo­ther­mal heat flux are con­side­red “signi­fi­cant” for gla­cier and ice sheet dyna­mics. The Thwai­tes Gla­cier is accor­din­gly loo­sing lar­ge volu­mes of ice due to mel­ting at its base. The geo­ther­mal heat flux is not influen­ced by cli­ma­te chan­ges, as oppo­sed to mel­ting that takes place near the coast, in the cont­act zone with sea water which is get­ting incre­asing­ly war­mer.

It is the geo­lo­gy which is respon­si­ble for sub-gla­cial mel­ting. Wes­tern Ant­ar­c­ti­ca is geo­lo­gi­cal­ly acti­ve. Sci­en­tists belie­ve the­re is a rift sys­tem under the ice, simi­lar to the Rift Val­ley of east Afri­ca. This rift sys­tem invol­ves increased mag­ma move­ments in the crust and pos­si­bly vol­ca­nism at the gla­cier base, simi­lar to vol­ca­noes in Ice­land.

Don Blan­ken­ship, sci­en­tists of the Uni­ver­si­ty of Texas and one of the aut­hor of a recent­ly published stu­dy, descri­bed the Thwai­tes Gla­cier as fol­lows: The gla­cier “sits on some­thing more like a mul­ti-bur­ner sto­ve­top with bur­ners put­ting out heat at dif­fe­rent levels at dif­fe­rent loca­ti­ons. … And then you plop the most cri­ti­cal dyna­mi­cal­ly unsta­ble ice sheet on pla­net Earth in the midd­le of this thing, and then you try to model it. It’s vir­tual­ly impos­si­ble.”

But of cour­se sci­en­tists are try­ing to model the Thwai­tes Gla­cier to pre­dict its future dyna­mics. The new know­ledge about geo­ther­mal heat flux under the gla­cier will be a very valuable con­tri­bu­ti­on to new models.

Gla­cier in the Ant­ar­c­tic Pen­in­su­la: a dwarf com­pared to the Thwai­tes Gla­cier.

Glacier, Antarctic Peninsula

Source: Uni­ver­si­ty of Texas

Japan wants to con­ti­nue wha­ling in Ant­ar­c­ti­ca

They can’t just let it be: Japan’s con­ser­va­ti­ve prime minis­ter Shin­zo Abe has declared to plead for a con­ti­nua­tion of Japa­ne­se wha­ling. In ear­ly 2014, the hig­hest UN court had declared Japa­ne­se wha­ling in its cur­rent form for ille­gal, as it is declared as sci­en­ti­fic wha­ling, but is far from mee­ting any requi­re­ments to qua­li­fy as such. The ver­dict has, howe­ver, left the pos­si­bi­li­ty open to orga­ni­ze a new wha­ling pro­gram­me that could meet the requi­re­ments, which include a stron­ger focus on non-lethal methods and rele­vant publi­ca­ti­ons.

Abe is quo­ted say­ing that he wants to streng­then sci­en­ti­fic rese­arch on wha­le popu­la­ti­ons and thus achie­ve new com­mer­cial wha­ling – remar­kab­le how “sci­en­ti­fic” and com­mer­cial wha­ling are con­nec­ted in the per­spec­ti­ve of the Japa­ne­se govern­ment. Abe also expres­sed it is sad that eating wha­le meat is not inter­na­tio­nal­ly reco­gni­zed as part of Japa­ne­se cul­tu­re. This part of Japa­ne­se cul­tu­re does, howe­ver, enjoy only limi­t­ed popu­la­ri­ty even in Japan: demand for wha­le meat is lower than sup­p­ly, despi­te com­mer­cial and even govern­men­tal pro­mo­ti­on.

Min­ke wha­le in the Ant­ar­c­tic Pen­in­su­la. In 2005, Japan kil­led about 3500 Min­ke wha­les for “sci­en­ti­fic pur­po­ses”.

Minke whale, Antarctic peninsula

Source: Spie­gel online

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