Since it snapped off the Larsen C deoxyephedrine shelfin July 2017 , the trillion - long ton iceberg known as A68 has spent most of its timestuck in the clay . Now , new satellite information reveals that the ‘ berg made its biggest move yet over the austral wintertime — a dramatic counterclockwise rotation that record no signs of stopping .
About a quarter the size of Wales or half the size of Jamaica , A-68 is the sixth largest iceberg lettuce on phonograph recording grant to the UK - base Antarctic enquiry groupProject MIDAS . Its falling out from the Larsen C trash shelf following month of make - up captivated the world last year . But since then , our care has drifted elsewhere as the iceberg futzed around aimlessly , repeatedly becoming pinned to the seabed , or ground , in a shallow area love as the Bawden Ice Rise .
But in July , under the cloak of darkness that is the Antarctic winter , A-68 set out to swing northward . Polar oceanographer Mark Brandon recentlyspotted the actionusing brightness temperature data point garner by the Suomi NPP satellite . This data produces false - color prototype where warmer area like sea water shine more brightly than cooler area , such as meth - covered surfaces .
Gif: Maddie Stone (Data via NASA Worldview)
The images understandably show A-68 making a large counterclockwise swing starting in former July . By the goal of August , the ‘ berg had rotated itself about 90 degree , becoming nearly perpendicular with the ledge . NASA glaciologist Christopher Shuman told Earther he estimate that A-68 has go around 10 arcdegree in the retiring two weeks alone , with almost 30 level of rotary motion in the two weeks prior .
What coiffe A-68 in motion ? Nobody ’s sure . “ One of the problem we have here is that the seabed in this orbit is fair ill mapped , ” glaciologist and former Project MIDAS collaboratorMartin O’Learytold Earther via email . “ It ’s usually clogged with ocean ice , which gain it problematic to get boats in there . ”
Indeed , thick sea icefoileda British Antarctic Survey - led attempt to reach the giant iceberg and study that seabed back in March .
Still , O’Leary read the iceberg ’s recent rotation probably indicates that it ’s derive loose from whatever it had been immobilize against for the past twelvemonth .
“ It might have been shaken loose by wind or sea currents , or it might be that the rude thinning unconscious process ( from both thaw and the flow of the ice ) has lifted the bottom of the iceberg off the sea bed , ” he said . “ In any case , it looks like the berg is now a draw more free to move about , so it will probably continue to rotate , and to move out to ocean . ”
Brandon suspects that A-68 will bear on on its present class , finally clash with the Larsen C shelf . “ It has a striking amount of momentum and it ’s not going to stop over easily , ” hewrotein a web log situation . While O’Leary says a hit is “ certainly possible ” he doubt it would have much of an issue on either ‘ berg or shelf given the dense - movement speed at which it would go on .
Eventually , O’Leary says the prevail ocean current will push the iceberg due north and eastwards into the Southern Ocean “ where it will in all likelihood violate up and melt . ”
We ’ll have to wait and see what ’s in store next for A-68 . But it seems that this iceberg has n’t finish making a spectacle of itself .
Update : This article has been updated to clarify that the change to the berg occurred over the Southern Hemisphere wintertime .
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