Questões de Inglês - Presente perfeito | Present perfect para Concurso

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ICEBERG A68a

   An enormous iceberg that is heading toward the island of South Georgia in the southern Atlantic Ocean has broken up into three large chunks. Scientists from NASA have been tracking the berg - dubbed A68a - for several weeks. It actually calved from the Larsen C ice shelf in 2017 and has been floating northwards ever since. In recent weeks, a fast-moving stream of water known as the Southern Antarctic Circumpolar Current Front has put the chunks on a trajectory that means they could run aground off the coast of South Georgia. Scientists say the three fragments are roughly 2,600 square kilometres in size. The submerged part of one chunk is 106 metres at its thickest point.

   The sheer bulk of the three iceberg chunks poses a serious threat to the wildlife of South Georgia. There could be an environmental catastrophe waiting to happen. If the three mini icebergs collide with the seabed, they could obstruct penguins and seals from foraging for fish. They could also block the route between penguin colonies and their feeding grounds during the breeding season. Scientists worry the underside of the fragments could grind the seabed near South Georgia and disrupt delicate underwater ecosystems. This could be exacerbated by the introduction of a mass of fresh water to the ecosystems as the stationary fragments melt over the summer months. 

Available at: https://breakingnewsenglish.com/2012/201229-iceberg-a68a.html Accessed on January 5th 2021.