Sentences with phrase «deep ice shelf»

The Canadian one created a 1000 - meter - deep ice shelf pushing out into the Arctic on the continental shelf off northern Alaska.

Not exact matches

It forced the ice to retreat but stopped at about 7,500 years ago, when the belt of westerly winds driving the deep water onto the shelf shifted northwards.

This isolated cavity of seawater, down at the grounding zone, sits deep beneath the back corner of the ice shelf — 850 kilometers back from where the edge of the ice meets the open sea.

MELT OFF Off the coast of the western Antarctic Peninsula (shown), upwelling of relatively warm, deep water has been linked to the melting of ice shelves, which help buttress the region's glaciers.

Within two years, scientists from the Woods Hole Oceanographic Institution and the University of Maryland will release self - guided robots to visit the hydrothermal vents deep beneath the Arctic ice shelves for the first time.

«If protective ice shelves were suddenly lost in the vast areas around the Antarctic margin where reverse - sloping bedrock (where the bed on which the ice sheet sits deepens toward the continental interior, rather than toward the ocean) is more than 1,000 meters deep, exposed grounding line ice cliffs would quickly succumb to structural failure as is happening in the few places where such conditions exist today,» the researchers point out.

The shelves slow and stabilize the glaciers behind them, but they are succumbing to a hidden force: Deep, warming ocean currents are melting the ice from beneath.

About 19 months after the wind churned the ocean, cycling warm deep waters upward and sending the cold surface waters down, the Totten ice shelf was noticeably thinner and had sped up.

The ice shelf floats within a pool of its own cold meltwater that sits atop a deeper, saltier and warmer layer; the two layers generally don't mix, like oil and water.

While researchers quickly linked the breakup to lakes of meltwater that had accumulated on the so - called Larsen B ice shelf's upper surface and then wedged apart deep crevasses, they hadn't come up with a convincing explanation for what triggered the collapse.

One 2004 NASA - led study found that most of the glaciers they were studying «flow into floating ice shelves over bedrock up to hundreds of meters deeper than previous estimates, providing exit routes for ice from further inland if ice - sheet collapse is under way.»

The findings, published yesterday in the journal Nature, show that during the past 11,000 years, wind patterns have driven relatively warm waters from the deep ocean onto Antarctica's continental shelf, leading to significant and sustained ice loss.

There are many ice shelves but the biggest (about the size of France) is the Ross Ice Shelf, tucked into a deep embayment in West Antarctiice shelves but the biggest (about the size of France) is the Ross Ice Shelf, tucked into a deep embayment in West AntarctiIce Shelf, tucked into a deep embayment in West Antarctica.

In Antarctica, even though as a whole it's slightly gaining in sea ice cover, most of these gains are over unproductive, deep - lying seabeds, whereas the newly ice - free areas are mostly located over highly productive continental shelves in the West Antarctic.

, most of these gains are over unproductive, deep - lying seabeds, whereas the newly ice - free areas are mostly located over highly productive continental shelves in the West Antarctic.

These ice shelves are being thinned from below as they are warmed by Circumpolar Deep Water11, which is being increasingly transported onto the continental shelf12, 13, 14.

The ice shelf around Pine Island Glacier is currently thinning, and it is warmed from below by Circumpolar Deep Water that flows onto the continental shelf22, 23.

Around the Antarctic Peninsula, changes in ocean currents, and in particular, changes in circumpolar deep water flowing onto the continental shelf, is melting ice shelves from below.

The highest rates of thinning are where relatively warm ocean currents can access the base of ice shelves through deep troughs [9,10].

In this case, incursions of circumpolar deep water onto the continental shelf are melting the ice stream at its base and encouraging grounding line recession, which results in a positive feedback loop and further grounding line recession.

In particular, I won't be surprised if continued decade - to - decade variability in atmospheric circulation results in more, and less, intrusion of circumpolar deep water onto the continental shelf, and to more, and less, rapid thinning of ice shelves in West Antarctica *.

At the other end of the ThC by Antarctica the deep current (having surrendered its heat south of the Falklands) appears to swing northwards from the vicinity of the Ross Sea ice shelf to run up past the east of the New Zealand continental shelf.

But as relatively warm water from deep reaches of the Southern Ocean moved onto the continental shelf, the thinning sped up, melting the ice shelves from underneath, the researchers of the new study concluded.

This out - flow of water from under the ice pulls in more deep water to melt more ice from the bottom of the ice shelf.

Their mission: find vulnerabilities where warmer (but still near freezing) water from the deep ocean may be seeping in under the ice shelf and melting it from below.

Rignot, who was not involved in the new Cosgrove study, told Eos in an email that Minzoni's study confirms that Circumpolar Deep Water «IS the major factor» for Antarctic ice shelf melting.

Whether its deep warm ocean currents melting floating ice shelfs or the remnants of a far away tsunami, huge icebergs are a natural result.

Researchers concluded that «Continuation of a deep thermocline would reverse the current ice - shelf thinning.»

But deep water production by convection may be less, depending on how much NADW is Arctic in origin and how much is simply recirculated Antarctic bottom water (extremely dense water, formed as brine under the sea ice around polynas offshore of Antarctica and sliding down the continental shelf into the depths without much mixing, creates a giant pool of dense water extending all the way up the bottom of the Atlantic to about 60 ° N).

236 Leonid Polyak, Margo H. Edwards, Bernard J. Coakley, Martin Jakobsson, «Ice shelves in the Pleistocene Arctic Ocean inferred from glaciogenic deep - sea bedforms,» Nature 410:453 - 457 (22 March 2001).

«Deep channels under the ice allow warm water to flow all the way to the grounding line, where the ice shelf meets the bedrock,» said Michael Studinger, a researcher with the mission.

Over these shelf areas, ice is absent at least part of the year, but ice is found year - round over the deep ocean.

Rapid sea - level rise from these processes is limited to those regions where the bed of the ice sheet is well below sea level and thus capable of feeding ice shelves or directly calving icebergs rapidly, but this still represents notable potential contributions to sea - level rise, including the deep fjords in Greenland (roughly 0.5 m; Bindschadler et al., 2013), parts of the East Antarctic ice sheet (perhaps as much as 20 m; Fretwell et al., 2013), and especially parts of the West Antarctic ice sheet (just over 3 m; Bamber et al., 2009).

Observations and numerical modeling reveal large fluctuations in the ocean heat available in the adjacent bay and enhanced sensitivity of ice - shelf melting to water temperatures at intermediate depth, as a seabed ridge blocks the deepest and warmest waters from reaching the thickest ice.

Even zero - degree seawater at outer continen tal shelf depths could expose ice shelves with deep grounding lines like the Totten (2.2 km), Moscow (2.0 km) and Shackleton (1.8 km) to temperatures more than 3 °C above their melting points.»

Scientists from the Netherlands have identified a mechanism that can trigger melting deep in the huge ice shelf.