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Fossilised pollen reveals climate history of northern Antarctica
Analysis of direct climate record shows Antarctic tundra persisted until 12 million years ago

A painstaking examination of the first direct and detailed climate record from the continental shelves surrounding Antarctica reveals that the last remnant of Antarctic vegetation existed in a tundra landscape on the continent's northern peninsula about 12 million years ago. The research, which was led by researchers at Rice University and Louisiana State University, appears online this week and will be featured on the cover of the July 12 issue of the Proceedings of the National Academy of Sciences.
The new study contains the most detailed reconstruction to date of the climatic history of the Antarctic Peninsula, which has warmed significantly in recent decades. The rapid decline of glaciers along the peninsula has led to widespread speculation about how the rest of the continent's ice sheets will react to rising global temperatures.

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Fossilised pollen reveals climate history of Northern Antarctica



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Antarctic survey reveals rugged buried landscape

The belly of Antarctica has given up a little more of its mystery.
Survey data taken across a great swathe of the east of the white continent has allowed scientists to map the shape of the bedrock buried deep under the ice.
It reveals in new detail a huge trough hundreds of kilometres long that is cut by fjord-like features.
Researchers tell Nature magazine that this hidden landscape was probably moulded by the action of glaciers more than 14 million years ago.

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New Map Reveals Giant Fjords Beneath East Antarctic Ice Sheet

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Scientists from the U.S., U.K. and Australia have used ice-penetrating radar to create the first high-resolution topographic map of one of the last uncharted regions of Earth, the Aurora Subglacial Basin, an immense ice-buried lowland in East Antarctica larger than Texas.
The map reveals some of the largest fjords or ice cut channels on Earth, providing important insights into the history of ice in Antarctica. The data will also help computer modellers improve their simulations of the past and future Antarctic ice sheet and its potential impact on global sea level.

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Scientists find traces of life without relying on the usual fossils

Ichnology is the study of the "traces" created by animals, such as burrows, footprints and tracks. Stephen Hasiotis is an expert in paleoichnology, which involves trace fossils created by organisms that lived in the distant past.
In the case of the team's fieldwork in Antarctica, the period is a few tens of millions of years on either side of the Permian-Triassic boundary. That's the time about 250 million years ago when the world's largest extinction event occurred, wiping out about 96 percent of marine species and 70 percent of terrestrial ones.

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Antarctic ice sheet built 'bottom-up'

Scientists have seen once again just how dynamic a place the underside of the Antarctic ice sheet can be.
Survey data collected from the middle of the White Continent shows liquid water is being frozen on to the bottom of the sheet in huge quantities.
In places, this deeply buried add-on layer is hundreds of metres thick and represents about half of the entire ice column, researchers say.

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New discovery from Antarctica's 'ghost mountains'

The discovery of numerous large ice structures within Antarctica's Dome A region, the site of the buried 'ghost mountains', reveals new understanding about ice sheet growth and movement that is essential for predicting how the ice sheet may change as the Earth's climate warms.
Reporting this week in the journal Science a six-nation group of scientists studying the Gamburtsev Subglacial Mountains describe how these remarkable structures form.  Typically ice sheets grow when layers of snow are deposited on the surface, but the researchers found startling new evidence of growth at the base. Widespread re-freezing of large volumes of water to the underside of the ice sheet modifies its structure. In some places this process can account for up to half the ice sheet's thickness, and the growth caused by refreezing may be comparable to that occurring at the surface.

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Antarctica Traced from Space

Antarctica may not be the world's largest landmass -- it's the fifth-largest continent -- but resting on top of that land is the world's largest ice sheet. That ice holds more than 60 percent of Earth's fresh water and carries the potential to significantly raise sea level. The continent is losing ice to the sea, and scientists want to know how much.
Antarctica's ice generally flows from the middle of the continent toward the edge, dipping toward the sea before lifting back up and floating. The point where ice separates from land is called the "grounding line." For scientists, an accurate map of the grounding line is a first step toward a complete calculation of how much ice the continent is losing.

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Credit NASA

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Ridge clue to Antarctic ice loss

The discovery of an underwater ridge in West Antarctica could help explain why there has been an acceleration in the ice flowing from a glacier in the area.
Researchers suggest that the base of Pine Island Glacier once sat on the ridge, but recently became detached from the feature.

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Drilling into the unknown - the first exploration of a sub-glacial Antarctic lake is a major step closer
Scientists have located the ideal drill site for the first ever exploration of an Antarctic sub-glacial lake, a development that is likely to facilitate a revolution in climate-change research and which may lead to the discovery of life-forms cut off from the main line of evolution for millions of years. 
In a paper published in Geophysical Research Letters this week, scientists from Northumbria University, the University of Edinburgh and the British Antarctic Survey have revealed the optimal drill site for exploring Lake Ellsworth, a sub-glacial lake comparable in size to Lake Windermere which is covered by three kilometres of ice.

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An experiment to make some of the first sustained measurements of atmospheric and oceanic conditions surrounding a polynya in Antarctica yielded not only some interesting results but also set a flight record for unmanned aircraft.
John Cassano announced the achievement during a press conference at the American Geophysical Unions annual fall meeting last month in San Francisco, one of the largest science conferences in the world.
An assistant professor in the Department of Atmospheric and Oceanic Sciences at the University of Colorado in Boulder, Cassano said the unmanned aerial vehicle (UAV) made 16 flights, half of which were from an airfield near McMurdo Station to Terra Nova Bay, about 330 kilometers away.

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