Scientists have yet again, sounded a warning over global warming and have said that melting ice in and around Antarctica is now threatening to dramatically slow deep-water currents in oceans across the world. This, in turn, can impact the spread of fresh water, oxygen and life-sustaining nutrients for centuries.

The model created as part of the study indicates faster Antarctic ice melts are driving a "substantial slowdown" of circulation of water in the ocean depths if global carbon emissions continue to remain high. The researchers have published their findings in the journal 'Nature' on Wednesday, reported AFP.

The "overturning circulation" of waters in the deepest reaches of the oceans would slow by 40 per cent by 2050 in a high-emissions scenario, according to the study, which warned of impacts that would last "for centuries to come".&nbsp;

Matthew England, climate professor at University of New South Wales (UNSW), says that if the model holds true, the deep ocean current will be "on a trajectory that looks headed towards collapse"

Trillions of tonnes of cold, highly salty and oxygen-rich water sinks around Antarctica each year, sending a deep-water current northwards to the Indian, Pacific and Atlantic oceans, scientists say.&nbsp;

The greater volumes of melting ice make the Antarctic waters less dense and salty, however, slowing the deep-water circulation with consequences for climate, sea level and marine ecosystems.&nbsp;

"If the oceans had lungs, this would be one of them," England said.&nbsp;

He added that if oceans become stagnant below 4000 metres, "this would trap nutrients in the deep ocean, reducing the nutrients available to support marine life near the ocean surface."

UNSW emeritus professor John Church, who was not involved in the study, said there were many uncertainties about the impact of a declining deep ocean circulation.&nbsp;

"But it seems almost certain that continuing on a high greenhouse gas emission pathway will lead to even more profound effects on the ocean and the climate system," Church said.&nbsp;

"The world urgently needs to drastically reduce our emissions to get off the high-emission pathway we are currently following."&nbsp;

The study team included lead author Qian Li of the Massachusetts Institute of Technology and co-authors from the Australian National University and Australia's national research organisation CSIRO.&nbsp;

(With inputs from agencies)

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Scientists have yet again, sounded a warning over global warming and have said that melting ice in and around Antarctica is now threatening to dramatically slow deep-water currents in oceans across the world.

Scientists have yet again, sounded a warning over global warming and have said that melting ice in and around Antarctica is now threatening to dramatically slow deep-water currents in oceans across the world. This, in turn, can impact the spread of fresh water, oxygen and life-sustaining nutrients for centuries. The model created as part of the study indicates faster Antarctic ice melts are driving a "substantial slowdown" of circulation of water in the ocean depths if global carbon emissions continue to remain high. The researchers have published their findings in the journal 'Nature' on Wednesday, reported AFP. The "overturning circulation" of waters in the deepest reaches of the oceans would slow by 40 per cent by 2050 in a high-emissions scenario, according to the study, which warned of impacts that would last "for centuries to come". Matthew England, climate professor at University of New South Wales (UNSW), says that if the model holds true, the deep ocean current will be "on a trajectory that looks headed towards collapse" Trillions of tonnes of cold, highly salty and oxygen-rich water sinks around Antarctica each year, sending a deep-water current northwards to the Indian, Pacific and Atlantic oceans, scientists say. The greater volumes of melting ice make the Antarctic waters less dense and salty, however, slowing the deep-water circulation with consequences for climate, sea level and marine ecosystems. "If the oceans had lungs, this would be one of them," England said. He added that if oceans become stagnant below 4000 metres, "this would trap nutrients in the deep ocean, reducing the nutrients available to support marine life near the ocean surface." UNSW emeritus professor John Church, who was not involved in the study, said there were many uncertainties about the impact of a declining deep ocean circulation. "But it seems almost certain that continuing on a high greenhouse gas emission pathway will lead to even more profound effects on the ocean and the climate system," Church said. "The world urgently needs to drastically reduce our emissions to get off the high-emission pathway we are currently following." The study team included lead author Qian Li of the Massachusetts Institute of Technology and co-authors from the Australian National University and Australia's national research organisation CSIRO. (With inputs from agencies) You can now write for wionews.com and be a part of the community. Share your stories and opinions with us here. WATCH WION LIVE HERE ×

Melting ice in Antarctica may impact oceans 'for centuries': Study

Scientists have sounded alarm over Antarctic sea ice reaching record low levels for the third time in six years.&nbsp;The sea level witnessed a drastic drop in the month of February this year, breaking the 2022 record.

On February 25 last year, the amount of sea ice dropped to 1.92m sq km – an all-time low recorded ever since satellite observations of ice floating in the ocean around Antarctica began in 1979.

But this record was already breached by February 12 this year, and by February 25, the ice level reached a new low of 1.79m sq km, beating the previous record by 136,000 sq km – an area double the size of Tasmania, reported the Guardian.

Dr Will Hobbs, an Antarctic sea ice expert at the University of Tasmania with the Australian Antarctic Programme Partnership, told Guardian that this was happening because of a "circumpolar event" and added that less ice is being witnessed everywhere.

He said that the large areas in the west of the continent had barely recovered from the previous year’s losses.

"Because sea ice is so reflective, it’s hard to melt from sunlight. But if you get open water behind it, that can melt the ice from underneath," Hobbs added.

The scientist said that the new record has the polar scientists scrambling for answers.

Antarctica continent holds enough ice to raise sea levels by many metres if it was to melt. Though melting of sea ice doesn’t directly correspond to a rise in sea levels as it is already floating in the water, several scientists the Guardian spoke to have raised concern over the spillover effects it can have on the ecosystem.

Apparently, sea ice helps negate the effect of storms on ice attached to the coast. If it starts to disappear for longer, the increased wave action can weaken those floating ice shelves that themselves stabilise the massive ice sheets and glaciers behind them on the land.

“We don’t want to lose sea ice where there are these vulnerable ice shelves and, behind them, the ice sheets,” Prof Matt England, an oceanographer and climate scientist at the University of New South Wales, was quoted as saying.

“We are probably starting to see signs of significant warming and retreat of sea ice [in Antarctica]. To see it getting to these levels is definitely a concern because we have these potentially amplifying feedbacks.”

(With inputs from agencies)

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Scientists have sounded alarm over Antarctic sea ice reaching record low levels for the third time in six years. The sea level witnessed a drastic drop in the month of February this year, breaking the 2022 record.

Scientists have sounded alarm over Antarctic sea ice reaching record low levels for the third time in six years. The sea level witnessed a drastic drop in the month of February this year, breaking the 2022 record. On February 25 last year, the amount of sea ice dropped to 1.92m sq km – an all-time low recorded ever since satellite observations of ice floating in the ocean around Antarctica began in 1979. But this record was already breached by February 12 this year, and by February 25, the ice level reached a new low of 1.79m sq km, beating the previous record by 136,000 sq km – an area double the size of Tasmania, reported the Guardian. Dr Will Hobbs, an Antarctic sea ice expert at the University of Tasmania with the Australian Antarctic Programme Partnership, told Guardian that this was happening because of a "circumpolar event" and added that less ice is being witnessed everywhere. He said that the large areas in the west of the continent had barely recovered from the previous year’s losses. "Because sea ice is so reflective, it’s hard to melt from sunlight. But if you get open water behind it, that can melt the ice from underneath," Hobbs added. The scientist said that the new record has the polar scientists scrambling for answers. Antarctica continent holds enough ice to raise sea levels by many metres if it was to melt. Though melting of sea ice doesn’t directly correspond to a rise in sea levels as it is already floating in the water, several scientists the Guardian spoke to have raised concern over the spillover effects it can have on the ecosystem. Apparently, sea ice helps negate the effect of storms on ice attached to the coast. If it starts to disappear for longer, the increased wave action can weaken those floating ice shelves that themselves stabilise the massive ice sheets and glaciers behind them on the land. “We don’t want to lose sea ice where there are these vulnerable ice shelves and, behind them, the ice sheets,” Prof Matt England, an oceanographer and climate scientist at the University of New South Wales, was quoted as saying. “We are probably starting to see signs of significant warming and retreat of sea ice [in Antarctica]. To see it getting to these levels is definitely a concern because we have these potentially amplifying feedbacks.” (With inputs from agencies) WATCH WION LIVE HERE

Scientists alarmed over Antarctic sea ice reaching record low levels

A satellite analysis on Wednesday (August 11) revealed that the world’s largest ice sheet has lost twice as much ice over the past 25 years as previously thought because Antarctica’s coastal glaciers are losing icebergs faster than the environment can restore the melting ice.

The study, led by scientists at NASA's Jet Propulsion Laboratory (JPL) and published in the journal Nature, raised new concerns about how quickly climate change is weakening Antarctica's floating ice shelves, which contribute to the rising global sea levels.

Also read |&nbsp;<a href="https://www.wionews.com/science/nasas-hubble-space-telescope-captures-stunning-picture-of-star-cluster-505722">NASA's Hubble Space Telescope captures stunning picture of star cluster</a>

It takes thousands of years for ice shelves to form. Once formed, they act as buttresses to hold back glaciers from slipping into oceans, or else they can raise sea levels. Their size is constant as a cycle of calving and regrowth keeps them. However, in recent decades, warmer oceans have damaged the shelves from below.

The main conclusion of the study concluded that the net loss of Antarctic ice from coastal glaciers calving into the ocean is equal to the net quantity of ice that scientists already knew was being lost due to thinning caused due to melting of glaciers. The study further claimed that the thinning and calving, the total has decreased the bulk of Antarctica’s ice shelves by 12 trillion tonnes since the year 1997, twice more than anticipated, the same area as Switzerland. According to him, 88 per cent of the world’s ice could raise the sea level.

Also read |&nbsp;<a href="https://www.wionews.com/science/nasa-shares-rare-pictures-of-record-summer-melting-in-svalbard-norways-ice-covered-archipelago-504528">NASA shares rare pictures of record summer melting in Svalbard, Norway’s ice-covered archipelago</a>

Chad Greene, JPL scientist in a press release said, "Antarctica is crumbling at its edges."

According to NASA, losses between the year 2002 to 2022 were roughly 149 million tonnes per year. The team used satellite photos to measure and record glacier flow and calving since 1997. Researchers concluded that Antarctica will reach the glacier levels pre-2000s by the end of this century.

(With inputs from agencies)

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A satellite analysis on Wednesday (August 11) revealed that the world’s largest ice sheet has lost twice as much ice over the past 25 years as previously thought because Antarctica’s coastal glaciers are losing icebergs faster than the environment can restore the melting ice.

A satellite analysis on Wednesday (August 11) revealed that the world’s largest ice sheet has lost twice as much ice over the past 25 years as previously thought because Antarctica’s coastal glaciers are losing icebergs faster than the environment can restore the melting ice. The study, led by scientists at NASA's Jet Propulsion Laboratory (JPL) and published in the journal Nature, raised new concerns about how quickly climate change is weakening Antarctica's floating ice shelves, which contribute to the rising global sea levels. Also read | NASA's Hubble Space Telescope captures stunning picture of star cluster It takes thousands of years for ice shelves to form. Once formed, they act as buttresses to hold back glaciers from slipping into oceans, or else they can raise sea levels. Their size is constant as a cycle of calving and regrowth keeps them. However, in recent decades, warmer oceans have damaged the shelves from below. The main conclusion of the study concluded that the net loss of Antarctic ice from coastal glaciers calving into the ocean is equal to the net quantity of ice that scientists already knew was being lost due to thinning caused due to melting of glaciers. The study further claimed that the thinning and calving, the total has decreased the bulk of Antarctica’s ice shelves by 12 trillion tonnes since the year 1997, twice more than anticipated, the same area as Switzerland. According to him, 88 per cent of the world’s ice could raise the sea level. Also read | NASA shares rare pictures of record summer melting in Svalbard, Norway’s ice-covered archipelago Chad Greene, JPL scientist in a press release said, "Antarctica is crumbling at its edges." According to NASA, losses between the year 2002 to 2022 were roughly 149 million tonnes per year. The team used satellite photos to measure and record glacier flow and calving since 1997. Researchers concluded that Antarctica will reach the glacier levels pre-2000s by the end of this century. (With inputs from agencies) WATCH WION LIVE HERE You can now write for wionews.com and be a part of the community. Share your stories and opinions with us here.

‘Antarctica is crumbling at its edges’: NASA's satellite image shows ice shelf thinning faster than predicted

Climate change is altering life on our planet in all ways possible: climate patterns have become more unpredictable, bizarre weather is the new normal, and extreme temperatures a common occurrence across the world.

Now, scientists have predicted the temperature of Antarctic peninsula in the coming decades. By 2044, the temperature in Arctic will increase by 0.5 to 1.5 degree Celsius, the study posits.

Precipitation in the peninsula is also expected to increase by 5-10 per cent around the same time. Precipitation is a threat to ice if&nbsp;it appears in the form of rain.

Also read:&nbsp;<a href="https://www.wionews.com/science/mystery-of-oumuamua-solved-find-out-where-the-foreign-space-object-came-from-371045" hreflang="en">Mystery of 'Oumuamua' solved: Find out where the foreign space object came from!</a> 
 
Lead author &nbsp;of the study, David Bromwich from The Ohio State University was quoted by IANS as saying - “We are concerned about these findings. We’ve been seeing overall quite big changes on the peninsula, generally getting warmer and ice shelves and glaciers discharging into the ocean”. 
 
Antarctica is one of the fastest-warming regions on the planet, especially since the 1950s. The most affected part is situated in western Antarctica, and is largely covered in mountains.&nbsp;The highest peak is 10,600 feet high!

Also read:&nbsp;<a href="https://www.wionews.com/science/what-really-happened-to-water-on-mars-scientists-finally-have-the-answer-371088" hreflang="en">What really happened to water on Mars? Scientists finally have the answer!</a> 
 
The study, which was published in the journal Climate Dynamics, takes into account simulations of 19 global climate models. The highest drop in temperatures of 2 degrees Celsius is expected to plague Antarctica between autumn and winter. 
 
But the summer temperatures pose a bigger threat to the peninsula’s ice. This implies the peninsula faces the double threat - of warmer temperatures, and potential precipitation in the form of rain, as opposed to snow.

Climate change is altering life on our planet in all ways possible: climate patterns have become more unpredictable, bizarre weather is the new normal, and extreme temperatures a common occurrence across the world.

Climate change is altering life on our planet in all ways possible: climate patterns have become more unpredictable, bizarre weather is the new normal, and extreme temperatures a common occurrence across the world. Now, scientists have predicted the temperature of Antarctic peninsula in the coming decades. By 2044, the temperature in Arctic will increase by 0.5 to 1.5 degree Celsius, the study posits. Precipitation in the peninsula is also expected to increase by 5-10 per cent around the same time. Precipitation is a threat to ice if it appears in the form of rain. Also read: Mystery of 'Oumuamua' solved: Find out where the foreign space object came from! Lead author of the study, David Bromwich from The Ohio State University was quoted by IANS as saying - “We are concerned about these findings. We’ve been seeing overall quite big changes on the peninsula, generally getting warmer and ice shelves and glaciers discharging into the ocean”. Antarctica is one of the fastest-warming regions on the planet, especially since the 1950s. The most affected part is situated in western Antarctica, and is largely covered in mountains. The highest peak is 10,600 feet high! Also read: What really happened to water on Mars? Scientists finally have the answer! The study, which was published in the journal Climate Dynamics, takes into account simulations of 19 global climate models. The highest drop in temperatures of 2 degrees Celsius is expected to plague Antarctica between autumn and winter. But the summer temperatures pose a bigger threat to the peninsula’s ice. This implies the peninsula faces the double threat - of warmer temperatures, and potential precipitation in the form of rain, as opposed to snow.

Scientists reveal how hot Antarctica will be by 2044 due to climate change

The year 2020 is the hottest in the Antarctic Peninsula in the past three decades, a study by the University of Santiago de Chile has said.

The Antarctic Peninsula is the northernmost part of Antarctica, where there are scientific and military bases from several countries, including Argentina, Chile and Britain.

Temperatures reached between 2 and 3 degrees Celsius (35.6 and 37.4 degrees Fahrenheit) on the peninsula between January and August, which is the northernmost part of mainland Antarctica, according to researchers at the Chilean Air Force's Frei Base on King George Island.

Those temperatures are "more than 2 degrees Celsius over typical values," climatologist Raul Cordero said in a statement released by the Chilean Antarctic Institute (INACH).&nbsp;In addition, the average maximum temperature in the far northern tip of the Antarctic Peninsula so far this year has been above 0 degrees. This had not happened for 31 years.

Researchers have termed that fact "alarming," since it could indicate that the rapid rate of ocean warming observed in the area at the end of the 20th century is resuming.

The high Southern Hemisphere winter temperatures are in contrast, however, with those registered between August and September, which reached -16.8 degrees Celsius, the lowest since 1970.

The year 2020 is the hottest in the Antarctic Peninsula in the past three decades, a study by the University of Santiago de Chile has said. The Antarctic Peninsula is the northernmost part of Antarctica, where there are scientific and military bases from several countries, including Argentina, Chile and Britain.

The year 2020 is the hottest in the Antarctic Peninsula in the past three decades, a study by the University of Santiago de Chile has said. The Antarctic Peninsula is the northernmost part of Antarctica, where there are scientific and military bases from several countries, including Argentina, Chile and Britain. Temperatures reached between 2 and 3 degrees Celsius (35.6 and 37.4 degrees Fahrenheit) on the peninsula between January and August, which is the northernmost part of mainland Antarctica, according to researchers at the Chilean Air Force's Frei Base on King George Island. Those temperatures are "more than 2 degrees Celsius over typical values," climatologist Raul Cordero said in a statement released by the Chilean Antarctic Institute (INACH). In addition, the average maximum temperature in the far northern tip of the Antarctic Peninsula so far this year has been above 0 degrees. This had not happened for 31 years. Researchers have termed that fact "alarming," since it could indicate that the rapid rate of ocean warming observed in the area at the end of the 20th century is resuming. The high Southern Hemisphere winter temperatures are in contrast, however, with those registered between August and September, which reached -16.8 degrees Celsius, the lowest since 1970.

Antarctic Peninsula at warmest in decades, study says

Antarctica has lost a staggering three trillion tonnes of ice since 1992, according to a landmark study published Wednesday that suggests the frozen continent could redraw Earth's coastlines if global warming continues unchecked.

Two-fifths of that ice loss occurred in the last five years, a three-fold increase in the pace at which Antarctica is shedding its kilometres-thick casing, a consortium of 84 scientists reported in the journal Nature.

The findings should dispel any lingering doubts that the continent's ice mass is shrinking, the authors said.

They also highlight the existential threat facing low-lying coastal cities and communities home to hundreds of millions of people.

"We now have an unequivocal picture of what's happening in Antarctica," said co-lead author Eric Rignot, a scientist at NASA's Jet propulsion Laboratory who has been tracking Earth's ice sheets for two decades.

"We view these results as another ringing alarm for action to slow the warming of our planet."

Up to now, scientists have struggled in determining whether Antarctica has accumulated more mass through snowfall than it loses in meltwater run-off and ice flows into the ocean. &nbsp;

But more than two decades of satellite data -- the new findings draw from 24 separate space-based surveys -- have finally yielded a more complete picture. &nbsp;

Covering twice the area of the continental United States, Antarctica is blanketed by enough ice pack to lift global oceans by nearly 60 metres (210 feet).&nbsp;

More than 90 per cent of that frozen water sits atop East Antarctica, which has remained mostly stable even as climate change has driven up Earth's average surface temperature by a full degree Celsius (1.8 degrees Fahrenheit).&nbsp;

A step increase

Some studies had suggested a net gain in mass over recent decades.

West Antarctica, however, has proven far more vulnerable to global warming, especially the Antarctic Peninsula, where more than 6,500 square kilometres (2,500 square miles) of ice shelves have sheared off into the sea since 1995.

Already floating, ice shelves breaking off into icebergs do not add to sea level. But massive glaciers on West Antarctica slowly gliding seaward hold enough water to push oceans up by 3.5 metres (11 feet).&nbsp;

Two of these glaciers -- Pine Island and Thwaites -- have accelerated and are today seen as unstable. Together, they act as corks holding back ice mass further inland from falling into the ocean.&nbsp;

Nearly all of the mass shed over the last quarter century has come from West Antarctica, the study found.&nbsp;

Ice loss of 2.7 trillion tonnes since 1992 added about eight millimetres to sea level.&nbsp;

"Whilst there's still considerable uncertainty about East Antarctica mass balance, it is increasingly clear that ice loss from West Antarctica has accelerated," said Kate Hendry, a researcher at the University of Bristol, commenting on the findings.

On current trends, Antarctica could become the single largest source of sea level rise, ahead of runoff from the Greenland ice sheet and mountain glaciers, and the expansion of ocean water as it warms, the study found.&nbsp;

Oceans are currently rising by 3.4 millimetres (0.13 inches) per year. Since 1993, the global ocean watermark has gone up by 84.8 mm (3.3 inches).

By century's end, sea level -- compared to a pre-industrial benchmark -- could increase from a few dozen centimetres to a metre or more, depending in part on efforts to curb greenhouse gas emissions.&nbsp;

Under any scenario, oceans will continue to rise for several centuries, scientists say.

Deeply concerning

In the two decades prior to 2012, Antarctica lost about 76 billion tonnes annually, according to the new findings. Since then, that figure has jumped, on average, to 219 billion tonnes. &nbsp;

"There has been a step increase in ice losses from Antarctica during the past decade," said Leeds University professor Andrew Shepherd, co-leader of the Ice Sheet Mass Balance Exercise (ISMBE).&nbsp;

"The continent is causing sea levels to rise faster today than at any time in the past 25 years."

Scientists not involved with the study lauded its methodology.

"The power of this research is that it brings together independent methods and results from a collection of different teams throughout the world," noted Twila Moon, a scientist at the US National Snow and Ice Data Center in Colorado.

They also said governments should take note.

"The outcome is deeply concerning," commented Imperial College London professor Martin Siegert, who did not take part in the study.&nbsp;

"We appear to be on a pathway to substantial ice-sheet loss in the decades ahead, with longer term consequences for enhanced sea level rise.

"If we aren't already alert to the dangers posed by climate change, this should be an enormous wake-up call," he added.

The finding was reported by a consortium of 84 scientists reported in the journal Nature. 'We view these results as another ringing alarm for action to slow the warming of our planet,' they said

Antarctica has lost a staggering three trillion tonnes of ice since 1992, according to a landmark study published Wednesday that suggests the frozen continent could redraw Earth's coastlines if global warming continues unchecked. Two-fifths of that ice loss occurred in the last five years, a three-fold increase in the pace at which Antarctica is shedding its kilometres-thick casing, a consortium of 84 scientists reported in the journal Nature. The findings should dispel any lingering doubts that the continent's ice mass is shrinking, the authors said. They also highlight the existential threat facing low-lying coastal cities and communities home to hundreds of millions of people. "We now have an unequivocal picture of what's happening in Antarctica," said co-lead author Eric Rignot, a scientist at NASA's Jet propulsion Laboratory who has been tracking Earth's ice sheets for two decades. "We view these results as another ringing alarm for action to slow the warming of our planet." Up to now, scientists have struggled in determining whether Antarctica has accumulated more mass through snowfall than it loses in meltwater run-off and ice flows into the ocean. But more than two decades of satellite data -- the new findings draw from 24 separate space-based surveys -- have finally yielded a more complete picture. Covering twice the area of the continental United States, Antarctica is blanketed by enough ice pack to lift global oceans by nearly 60 metres (210 feet). More than 90 per cent of that frozen water sits atop East Antarctica, which has remained mostly stable even as climate change has driven up Earth's average surface temperature by a full degree Celsius (1.8 degrees Fahrenheit). A step increase Some studies had suggested a net gain in mass over recent decades. West Antarctica, however, has proven far more vulnerable to global warming, especially the Antarctic Peninsula, where more than 6,500 square kilometres (2,500 square miles) of ice shelves have sheared off into the sea since 1995. Already floating, ice shelves breaking off into icebergs do not add to sea level. But massive glaciers on West Antarctica slowly gliding seaward hold enough water to push oceans up by 3.5 metres (11 feet). Two of these glaciers -- Pine Island and Thwaites -- have accelerated and are today seen as unstable. Together, they act as corks holding back ice mass further inland from falling into the ocean. Nearly all of the mass shed over the last quarter century has come from West Antarctica, the study found. Ice loss of 2.7 trillion tonnes since 1992 added about eight millimetres to sea level. "Whilst there's still considerable uncertainty about East Antarctica mass balance, it is increasingly clear that ice loss from West Antarctica has accelerated," said Kate Hendry, a researcher at the University of Bristol, commenting on the findings. On current trends, Antarctica could become the single largest source of sea level rise, ahead of runoff from the Greenland ice sheet and mountain glaciers, and the expansion of ocean water as it warms, the study found. Oceans are currently rising by 3.4 millimetres (0.13 inches) per year. Since 1993, the global ocean watermark has gone up by 84.8 mm (3.3 inches). By century's end, sea level -- compared to a pre-industrial benchmark -- could increase from a few dozen centimetres to a metre or more, depending in part on efforts to curb greenhouse gas emissions. Under any scenario, oceans will continue to rise for several centuries, scientists say. Deeply concerning In the two decades prior to 2012, Antarctica lost about 76 billion tonnes annually, according to the new findings. Since then, that figure has jumped, on average, to 219 billion tonnes. "There has been a step increase in ice losses from Antarctica during the past decade," said Leeds University professor Andrew Shepherd, co-leader of the Ice Sheet Mass Balance Exercise (ISMBE). "The continent is causing sea levels to rise faster today than at any time in the past 25 years." Scientists not involved with the study lauded its methodology. "The power of this research is that it brings together independent methods and results from a collection of different teams throughout the world," noted Twila Moon, a scientist at the US National Snow and Ice Data Center in Colorado. They also said governments should take note. "The outcome is deeply concerning," commented Imperial College London professor Martin Siegert, who did not take part in the study. "We appear to be on a pathway to substantial ice-sheet loss in the decades ahead, with longer term consequences for enhanced sea level rise. "If we aren't already alert to the dangers posed by climate change, this should be an enormous wake-up call," he added.

Antarctica ice melting three times faster than earlier, could redraw Earth's coastlines