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Global warming doubles growth rates of Antarctic seabed’s marine fauna – study

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Marine life on the Antarctic seabed is likely to be far more affected by global warming than previously thought, say scientists who have conducted the most sophisticated study to date of heating impacts in the species-rich environment.

Growth rates of some fauna doubled – including colonising moss animals and undersea worms – following a 1C increase in temperature, making them more dominant, pushing out other species and reducing overall levels of biodiversity, according to the study published  in Current Biology.

The researchers who conducted the nine-month experiment in the Bellingshuan Sea say this could have alarming implications for marine life across the globe as temperatures rise over the coming decades as a result of manmade greenhouse gases in the atmosphere.

Gail Ashton of the British Antarctic Survey and Smithsonian Environmental Research Center said she was not expecting such a significant difference. “The loss of biodiversity is very concerning. This is an indication of what may happen elsewhere with greater warning.”

Sub-zero conditions near the south pole mean there are comparatively few species on the usually frozen land, but below the ice, the relative lack of pollution, traffic and fishing has left an abundance of marine life that divers and biologists compare to coral reefs.

Previous studies of warming impacts have focused on single species, but the latest research examines an assemblage of creatures. Twelve identical 15cm sq heat plates were set in concrete on the seabed. Four were warmed by 1C, four by 2C and four left at ambient temperature as a control.

Until recently, most of the coverage of temperature rises has focused on the north pole, where the shrinking of arctic ice has been most visibly dramatic. But concerns are growing about the impact of global warming on the far bigger southern ice cap.

Follow for more information: https://www.theguardian.com/environment/2017/aug/31/global-warming-doubles-growth-rates-of-antarctic-seabeds-marine-fauna-study

This Antarctic glacier is cracking from the inside out and that’s bad news for all of us

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A massive glacier at the edge of the West Antarctic Ice Sheet is cracking from the inside out at accelerating speed. That’s alarming because this glacier — and others — function like corks in a bottle: they keep the ice from flowing into the sea, which would raise sea levels by several feet.

The glacier, which is described in a paper published in Geophysical Research Letters, is called Pine Island Glacier. In 2015, a 224-square-mile iceberg broke off from the glacier. After studying satellite images before and after the event, researchers at Ohio State University found that in 2013, a rift formed at the base of the ice shelf, 20 miles inland. The rift worked its way up for two years until it caused the iceberg to break off.

Icebergs do separate from ice sheets in the Antarctic on a fairly regular basis. This one, though, is special. It confirmed what glaciologists have long been suspecting: that the ice shelf is weakening. But it also shows that the ice retreat is happening farther inland than scientists had previously observed.

Read more about that serious issue: http://www.theverge.com/2016/11/29/13780410/antarctica-glacier-ice-sheet-melting-sea-level-rising