Tag Archives: Antarctic

Glaciers’ global melt may leave Alps bare

High mountain ice is vital to millions. As the world warms, the glaciers’ global melt could see the frozen peaks vanish.

LONDON, 12 April, 2019 – Many of the planet’s most scenic – and most valued – high-altitude landscapes are likely to look quite different within the next 80 years: the glaciers’ global melt will have left just bare rock.

By the century’s end, Europe’s famous Alps – the chain of snow- and ice-covered peaks that have become a playground of the wealthy and a source of income and pleasure for generations – will have lost more than nine-tenths of all its glacier ice.

And in the last 50 years, the world’s glaciers – in Asia, the Americas, Europe, Africa and the sub-Arctic mountains – have lost more than nine trillion tonnes of ice as global temperatures creep ever upwards in response to profligate combustion of fossil fuels.

And as meltwater has trickled down the mountains, the seas have risen by 27mm, thanks entirely to glacial retreat.

“Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century”

In two separate studies, Swiss scientists have tried to audit a profit and loss account for the world’s frozen high-altitude rivers, and found a steady downhill trend.

Glacial ice is a source of security and even wealth: in the poorest regions the annual summer melt of winter snow and ice banked at altitude can guarantee both energy as hydropower and water for crops in the valleys and floodplains.

In wealthy regions, the white peaks and slopes become sources of income as tourist attractions and centres for winter sport – as well as reliable sources of power and water.

Swiss focus

In the journal The Cryosphere, a team from the Swiss Federal Institute of Technology, almost always known simply as ETH Zurich, looked into the future of the nation’s own landscape, and beyond.

They made computer models of the annual flow of ice and its melting patterns and took 2017 as the reference year: a year when the Alpine glaciers bore 100 cubic kilometres of ice. And then they started simulating the future.

If humankind kept the promise made by 195 nations in Paris in 2015, to drastically reduce fossil fuel use, lower emissions of carbon dioxide, restore the forests and keep global warming to no more than 2°C above historic levels, then the stores of high ice would be reduced by more than a third over the next eight decades. If humankind went on expanding its use of fossil fuels at the present rates, then half of all the ice would be lost by 2050 and 95% by 2100.

Time lag

But there will be losses in all scenarios: warming so far has seen to that. Ice reflects radiation and keeps itself cold, so change lags behind atmospheric temperature.

“The future evolution of glaciers will strongly depend on how the climate will evolve,” said Harry Zekollari, once of ETH and now at Delft University of Technology in the Netherlands, who led the research. “In the case of a more limited warming, a far more substantial part of the glaciers could be saved.”

The Alpine glaciers were made world-famous first by Romantic painters and poets of the 19th century, among them JMW Turner and Lord Byron. But their contribution to rising sea levels is, in a global context, negligible.

When Swiss researchers and their Russian, Canadian and European partners looked at the big picture, they found that the mass loss of ice from the mountains of AlaskaCanada, parts of Asia and the Andes matched the increasing flow of water from the melting Greenland ice cap, and exceeded the flow of melting water from the Antarctic continent.

Europe’s modest melt

They report in Nature that glaciers separate from the Greenland and Antarctic sheets covered 706,000 square kilometres of the planet, with a total volume of 170,000 cubic kilometres, or 40 centimetres of potential sea level rise.

And in the five decades from 1961 to 2016, according to careful study of satellite imagery and historic observations, the seas have already risen by 27mm as a consequence of increasing rates of glacial retreat. This is already between 25% and 30% of observed sea level rise so far.

Europe did not figure much in the reckoning. “Globally, we lose three times the ice volume stored in the entirety of the European Alps – every single year,” said Michael Zemp, a glaciologist at the University of Zurich.

He and his colleagues warn: “Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century, while heavily glacierised regions will continue to contribute to sea level rise beyond 2100.” – Climate News Network

High mountain ice is vital to millions. As the world warms, the glaciers’ global melt could see the frozen peaks vanish.

LONDON, 12 April, 2019 – Many of the planet’s most scenic – and most valued – high-altitude landscapes are likely to look quite different within the next 80 years: the glaciers’ global melt will have left just bare rock.

By the century’s end, Europe’s famous Alps – the chain of snow- and ice-covered peaks that have become a playground of the wealthy and a source of income and pleasure for generations – will have lost more than nine-tenths of all its glacier ice.

And in the last 50 years, the world’s glaciers – in Asia, the Americas, Europe, Africa and the sub-Arctic mountains – have lost more than nine trillion tonnes of ice as global temperatures creep ever upwards in response to profligate combustion of fossil fuels.

And as meltwater has trickled down the mountains, the seas have risen by 27mm, thanks entirely to glacial retreat.

“Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century”

In two separate studies, Swiss scientists have tried to audit a profit and loss account for the world’s frozen high-altitude rivers, and found a steady downhill trend.

Glacial ice is a source of security and even wealth: in the poorest regions the annual summer melt of winter snow and ice banked at altitude can guarantee both energy as hydropower and water for crops in the valleys and floodplains.

In wealthy regions, the white peaks and slopes become sources of income as tourist attractions and centres for winter sport – as well as reliable sources of power and water.

Swiss focus

In the journal The Cryosphere, a team from the Swiss Federal Institute of Technology, almost always known simply as ETH Zurich, looked into the future of the nation’s own landscape, and beyond.

They made computer models of the annual flow of ice and its melting patterns and took 2017 as the reference year: a year when the Alpine glaciers bore 100 cubic kilometres of ice. And then they started simulating the future.

If humankind kept the promise made by 195 nations in Paris in 2015, to drastically reduce fossil fuel use, lower emissions of carbon dioxide, restore the forests and keep global warming to no more than 2°C above historic levels, then the stores of high ice would be reduced by more than a third over the next eight decades. If humankind went on expanding its use of fossil fuels at the present rates, then half of all the ice would be lost by 2050 and 95% by 2100.

Time lag

But there will be losses in all scenarios: warming so far has seen to that. Ice reflects radiation and keeps itself cold, so change lags behind atmospheric temperature.

“The future evolution of glaciers will strongly depend on how the climate will evolve,” said Harry Zekollari, once of ETH and now at Delft University of Technology in the Netherlands, who led the research. “In the case of a more limited warming, a far more substantial part of the glaciers could be saved.”

The Alpine glaciers were made world-famous first by Romantic painters and poets of the 19th century, among them JMW Turner and Lord Byron. But their contribution to rising sea levels is, in a global context, negligible.

When Swiss researchers and their Russian, Canadian and European partners looked at the big picture, they found that the mass loss of ice from the mountains of AlaskaCanada, parts of Asia and the Andes matched the increasing flow of water from the melting Greenland ice cap, and exceeded the flow of melting water from the Antarctic continent.

Europe’s modest melt

They report in Nature that glaciers separate from the Greenland and Antarctic sheets covered 706,000 square kilometres of the planet, with a total volume of 170,000 cubic kilometres, or 40 centimetres of potential sea level rise.

And in the five decades from 1961 to 2016, according to careful study of satellite imagery and historic observations, the seas have already risen by 27mm as a consequence of increasing rates of glacial retreat. This is already between 25% and 30% of observed sea level rise so far.

Europe did not figure much in the reckoning. “Globally, we lose three times the ice volume stored in the entirety of the European Alps – every single year,” said Michael Zemp, a glaciologist at the University of Zurich.

He and his colleagues warn: “Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century, while heavily glacierised regions will continue to contribute to sea level rise beyond 2100.” – Climate News Network

More acidic seas devour marine food web

As more acidic seas spread across the globe, conditions for survival start to change. That could close vast volumes of ocean for vital forms of life.

LONDON, 13 March, 2019 – By the close of the century, parts of the Southern Ocean could become impoverished as more acidic seas displace abundant marine food resources. Tiny sea snails that form the basis of the food supply for one of the world’s richest ecosystems could disappear because the depth at which they can form their shells will have shifted.

Right now, in Antarctic waters, creatures known as pteropods can exploit the calcium carbonate dissolved in the oceans down to a depth of 1000 metres to grow their shells.

But as atmospheric carbon dioxide levels soar, as a consequence of profligate use of fossil fuels by humankind, the chemistry of the oceans will shift towards the acidic.

The ratios of two kinds of carbonate – calcite and aragonite – will alter. And by 2100, there won’t be enough aragonite.

“A pocket of corrosive water will sit just below the surface, making life difficult for these communities of primarily surface-dwelling organisms”

Right now, pteropods flourish in the top 300 metres of the ocean. By 2100, the survival zone for the pteropods will end at a depth of 83 metres.

And, scientists warn in the journal Nature Climate Change, this could “change food web dynamics and have cascading effects on global ocean ecosystems.” In other words, the larger fish and marine mammals that feed on the smaller creatures that in turn depend on a basic diet of pteropods will have nothing to eat.

And that can only be bad news for global fisheries.

All shelled marine creatures – the tiny coccolithophores that die and leave their shells as chalk, the clams and molluscs, the foraminifera that float on the surface or coat the rocks and the seafloor, and the corals that are the basis for rich tropical ecosystems, all depend on the right levels of calcite and aragonite to form their exoskeletons.

The oceans are the biggest living space on the planet: the waves cover 70% of all living space and the depth of the deepest trenches is far greater than the highest terrestrial mountain ranges.

Origin of life

The oceans are the crucible in which life first emerged, and the oceans ultimately provided the sediments from which humankind has built its cities.

US and Norwegian scientists chose one species with precise needs in one reach of ocean as an indicator or what climate change driven by ever greater levels of the greenhouse gas carbon dioxide could do to an ocean ecosystem.

They found that what they called the “aragonite saturation horizon” became dramatically shallower as the seas became more acidic.

“These calcifying organisms will struggle to build and maintain their shells as acidification proceeds,” said Nicole Lovenduski, of the University of Colorado at Boulder, one of the researchers.

Inevitable result

“In the future, a pocket of corrosive water will sit just below the surface, making life difficult for these communities of primarily surface-dwelling organisms.”

As the world warms, acidification of the oceans becomes inevitable. Researchers have repeatedly warned that such change can only diminish ocean life, harm the coral reefs and kelp forests that shelter the rich biodiversity of sea creatures, change the behaviour of fish and some kinds of shrimp and threaten the shellfish harvest.

But for the first time, scientists have been able to model the impact of atmospheric change on the ocean chemistry in one zone at precise depths. The message is that right now, the pteropods have plenty of sea space for survival. But the aragonite saturation horizon may have already begun to shift in some places: perhaps as early as 2006, or as late as 2038. Once change begins, it will continue.

“If emissions were curbed tomorrow, this suddenly shallow horizon would still appear, even if possibly delayed,” said Dr Lovenduski. “And that, inevitably, along with lack of time for organisms to adapt, is most concerning.” – Climate News Network

As more acidic seas spread across the globe, conditions for survival start to change. That could close vast volumes of ocean for vital forms of life.

LONDON, 13 March, 2019 – By the close of the century, parts of the Southern Ocean could become impoverished as more acidic seas displace abundant marine food resources. Tiny sea snails that form the basis of the food supply for one of the world’s richest ecosystems could disappear because the depth at which they can form their shells will have shifted.

Right now, in Antarctic waters, creatures known as pteropods can exploit the calcium carbonate dissolved in the oceans down to a depth of 1000 metres to grow their shells.

But as atmospheric carbon dioxide levels soar, as a consequence of profligate use of fossil fuels by humankind, the chemistry of the oceans will shift towards the acidic.

The ratios of two kinds of carbonate – calcite and aragonite – will alter. And by 2100, there won’t be enough aragonite.

“A pocket of corrosive water will sit just below the surface, making life difficult for these communities of primarily surface-dwelling organisms”

Right now, pteropods flourish in the top 300 metres of the ocean. By 2100, the survival zone for the pteropods will end at a depth of 83 metres.

And, scientists warn in the journal Nature Climate Change, this could “change food web dynamics and have cascading effects on global ocean ecosystems.” In other words, the larger fish and marine mammals that feed on the smaller creatures that in turn depend on a basic diet of pteropods will have nothing to eat.

And that can only be bad news for global fisheries.

All shelled marine creatures – the tiny coccolithophores that die and leave their shells as chalk, the clams and molluscs, the foraminifera that float on the surface or coat the rocks and the seafloor, and the corals that are the basis for rich tropical ecosystems, all depend on the right levels of calcite and aragonite to form their exoskeletons.

The oceans are the biggest living space on the planet: the waves cover 70% of all living space and the depth of the deepest trenches is far greater than the highest terrestrial mountain ranges.

Origin of life

The oceans are the crucible in which life first emerged, and the oceans ultimately provided the sediments from which humankind has built its cities.

US and Norwegian scientists chose one species with precise needs in one reach of ocean as an indicator or what climate change driven by ever greater levels of the greenhouse gas carbon dioxide could do to an ocean ecosystem.

They found that what they called the “aragonite saturation horizon” became dramatically shallower as the seas became more acidic.

“These calcifying organisms will struggle to build and maintain their shells as acidification proceeds,” said Nicole Lovenduski, of the University of Colorado at Boulder, one of the researchers.

Inevitable result

“In the future, a pocket of corrosive water will sit just below the surface, making life difficult for these communities of primarily surface-dwelling organisms.”

As the world warms, acidification of the oceans becomes inevitable. Researchers have repeatedly warned that such change can only diminish ocean life, harm the coral reefs and kelp forests that shelter the rich biodiversity of sea creatures, change the behaviour of fish and some kinds of shrimp and threaten the shellfish harvest.

But for the first time, scientists have been able to model the impact of atmospheric change on the ocean chemistry in one zone at precise depths. The message is that right now, the pteropods have plenty of sea space for survival. But the aragonite saturation horizon may have already begun to shift in some places: perhaps as early as 2006, or as late as 2038. Once change begins, it will continue.

“If emissions were curbed tomorrow, this suddenly shallow horizon would still appear, even if possibly delayed,” said Dr Lovenduski. “And that, inevitably, along with lack of time for organisms to adapt, is most concerning.” – Climate News Network

Melting polar ice sheets will alter weather

Sea level rise and melting polar ice sheets may not cause a climate catastrophe, but they will certainly change weather patterns unpredictably.

LONDON, 15 February, 2019 – The global weather is about to get worse. The melting polar ice sheets will mean rainfall and windstorms could become more violent, and hot spells and ice storms could become more extreme.

This is because the ice sheets of Greenland and Antarctica are melting, to affect what were once stable ocean currents and airflow patterns around the globe.

Planetary surface temperatures could rise by 3°C or even 4°C by the end of the century. Global sea levels will rise in ways that would “enhance global temperature variability”, but this might not be as high as earlier studies have predicted. That is because the ice cliffs of Antarctica might not be so much at risk of disastrous collapse that would set the glaciers accelerating to the sea.

The latest revision of evidence from the melting ice sheets in two hemispheres – and there is plenty of evidence that melting is happening at ever greater rates – is based on two studies of what could happen to the world’s greatest reservoirs of frozen freshwater if nations pursue current policies, fossil fuel combustion continues to increase, and global average temperatures creep up to unprecedented levels.

“Even if we do include ice-cliff instability … the most likely contribution to sea level rise would be less than half a metre by 2100”

“Under current global government policies, we are heading towards 3 or 4 degrees of warming above pre-industrial levels, causing a significant amount of melt water from the Greenland and Antarctic ice sheets to enter Earth’s oceans. According to our models, this melt water will cause significant disruptions to ocean currents and change levels of warming around the world,” said Nick Golledge, a south polar researcher at Victoria University, in New Zealand.

He and colleagues from Canada, the US, Germany and the UK report in Nature that they matched satellite observations of what is happening to the ice sheets with detailed simulations of the complex effects of melting over time, and according to the human response so far to warnings of climate change.

In Paris in 2015, leaders from 195 nations vowed to contain global warming to “well below” an average rise of 2°C by 2100. But promises have yet to become concerted and coherent action, and researchers warn that on present policies, a 3°C rise seems inevitable.

Sea levels have already risen by about 14 cms in the last century: the worst scenarios have proposed a devastating rise of 130 cms by 2100. The fastest increase in the rise of sea levels is likely to happen between 2065 and 2075.

Gulf Stream weakens

As warmer melt water gets into the North Atlantic, that major ocean current the Gulf Stream is likely to be weakened. Air temperatures are likely to rise over eastern Canada, central America and the high Arctic. Northwestern Europe – scientists have been warning of this for years – will become cooler.

In the Antarctic, a lens of warm fresh water will form over the surface, allowing uprising warm ocean water to spread and cause what could be further Antarctic melting.

But how bad this could be is re-examined in a second, companion paper in Nature. Tamsin Edwards, now at King’s College London, Dr Golledge and others took a fresh look at an old scare: that the vast cliffs of ice – some of them 100 metres above sea level – around the Antarctic could become unstable and collapse, accelerating the retreat of the ice behind them.

They used geophysical techniques to analyse dramatic episodes of ice loss that must have happened 3 million years ago and 125,000 years ago, and they went back to the present patterns of melt. These losses, in their calculations, did not cause unstoppable ice loss in the past, and may not affect the future much either.

Instability less important

“We’ve shown that ice-cliff instability doesn’t appear to be an essential mechanism in reproducing past sea level changes and so this suggests ‘the jury’s still out’ when it comes to including it in future predictions,” said Dr Edwards.

“Even if we do include ice-cliff instability, our more thorough assessment shows the most likely contribution to sea level rise would be less than half a metre by 2100.”

At worst, there is a one in 20 chance that enough of Antarctica’s glacial burden will melt to raise sea levels by 39 cms. More likely, both studies conclude, under high levels of greenhouse gas concentrations, south polar ice will only melt to raise sea levels worldwide by about 15 cms. – Climate News Network

Sea level rise and melting polar ice sheets may not cause a climate catastrophe, but they will certainly change weather patterns unpredictably.

LONDON, 15 February, 2019 – The global weather is about to get worse. The melting polar ice sheets will mean rainfall and windstorms could become more violent, and hot spells and ice storms could become more extreme.

This is because the ice sheets of Greenland and Antarctica are melting, to affect what were once stable ocean currents and airflow patterns around the globe.

Planetary surface temperatures could rise by 3°C or even 4°C by the end of the century. Global sea levels will rise in ways that would “enhance global temperature variability”, but this might not be as high as earlier studies have predicted. That is because the ice cliffs of Antarctica might not be so much at risk of disastrous collapse that would set the glaciers accelerating to the sea.

The latest revision of evidence from the melting ice sheets in two hemispheres – and there is plenty of evidence that melting is happening at ever greater rates – is based on two studies of what could happen to the world’s greatest reservoirs of frozen freshwater if nations pursue current policies, fossil fuel combustion continues to increase, and global average temperatures creep up to unprecedented levels.

“Even if we do include ice-cliff instability … the most likely contribution to sea level rise would be less than half a metre by 2100”

“Under current global government policies, we are heading towards 3 or 4 degrees of warming above pre-industrial levels, causing a significant amount of melt water from the Greenland and Antarctic ice sheets to enter Earth’s oceans. According to our models, this melt water will cause significant disruptions to ocean currents and change levels of warming around the world,” said Nick Golledge, a south polar researcher at Victoria University, in New Zealand.

He and colleagues from Canada, the US, Germany and the UK report in Nature that they matched satellite observations of what is happening to the ice sheets with detailed simulations of the complex effects of melting over time, and according to the human response so far to warnings of climate change.

In Paris in 2015, leaders from 195 nations vowed to contain global warming to “well below” an average rise of 2°C by 2100. But promises have yet to become concerted and coherent action, and researchers warn that on present policies, a 3°C rise seems inevitable.

Sea levels have already risen by about 14 cms in the last century: the worst scenarios have proposed a devastating rise of 130 cms by 2100. The fastest increase in the rise of sea levels is likely to happen between 2065 and 2075.

Gulf Stream weakens

As warmer melt water gets into the North Atlantic, that major ocean current the Gulf Stream is likely to be weakened. Air temperatures are likely to rise over eastern Canada, central America and the high Arctic. Northwestern Europe – scientists have been warning of this for years – will become cooler.

In the Antarctic, a lens of warm fresh water will form over the surface, allowing uprising warm ocean water to spread and cause what could be further Antarctic melting.

But how bad this could be is re-examined in a second, companion paper in Nature. Tamsin Edwards, now at King’s College London, Dr Golledge and others took a fresh look at an old scare: that the vast cliffs of ice – some of them 100 metres above sea level – around the Antarctic could become unstable and collapse, accelerating the retreat of the ice behind them.

They used geophysical techniques to analyse dramatic episodes of ice loss that must have happened 3 million years ago and 125,000 years ago, and they went back to the present patterns of melt. These losses, in their calculations, did not cause unstoppable ice loss in the past, and may not affect the future much either.

Instability less important

“We’ve shown that ice-cliff instability doesn’t appear to be an essential mechanism in reproducing past sea level changes and so this suggests ‘the jury’s still out’ when it comes to including it in future predictions,” said Dr Edwards.

“Even if we do include ice-cliff instability, our more thorough assessment shows the most likely contribution to sea level rise would be less than half a metre by 2100.”

At worst, there is a one in 20 chance that enough of Antarctica’s glacial burden will melt to raise sea levels by 39 cms. More likely, both studies conclude, under high levels of greenhouse gas concentrations, south polar ice will only melt to raise sea levels worldwide by about 15 cms. – Climate News Network

Permafrost thaws as global warming sets in

Global warming is at work far below the surface, at depths seemingly insulated from the greenhouse effect. This is bad news for the permafrost.

LONDON, 29 January, 2019 – Even in the coldest places – 10 metres below the surface of the polar wastes – global warming has begun to work. A new study of the frozen soils in both hemispheres shows that between 2007 and 2016, they warmed by an average of 0.3°C.

This remained true within the Arctic and Antarctic zones, in the highest mountain regions of Europe and Asia, and even in the Siberian tundra, where the temperatures at depth rose by almost a whole degree.

New research into the permafrost, defined as territory where soil has been frozen for at least two consecutive years, suggests that much of it may not be permanently frozen for much longer.

Climate scientists have repeatedly warned that along with the tilth, clays and sediments the icy structures store vast amounts of carbon in the form of yet-to-be-decomposed plant material.

So the thawing permafrost could surrender even more warming agents in the form of greenhouse gases, and accelerate global warming even further.

“The permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming”

Researchers based in Potsdam, Germany report in the journal Nature Communications that they and colleagues in the Global Terrestrial Network for Permafrost monitored and measured soil temperatures in boreholes at 154 locations; more than 120 of them over a 10-year cycle. In a dozen locations the temperatures actually fell, and at 40 locations there was virtually no change.

The most dramatic warming was in the Arctic, where soils that were more than 90% permafrost increased temperatures by 0.3°C, and the Siberian north, where temperatures rose by 0.9°C or more. Air temperatures over those regions had risen by an average of 0.6°C in the same decade. In those Arctic regions with less than 90% permafrost, the frozen ground had warmed by 0.2°C.

“In these regions there is more and more snowfall, which insulates the permafrost in two ways, following the igloo principle,” said Boris Biskaborn of the Alfred Wegener Institute, at the Helmholtz Centre for Polar and Marine Research, who led the study.

“In winter snow protects the soil from extreme cold, which on average produces a warming effect. In spring it reflects the sunlight, and prevents the soils from being exposed to too much warmth, at least until the snow has completely melted away.”

Widespread impact

The scientists also report that soil temperature rises were recorded in the Alps of Europe, the mountain ranges of Scandinavia, and in the Himalayas.

Other scientists have already this year identified potential disaster for many settlements in the Arctic regions: the once-hard-frozen topsoils are in danger of thawing, and since these support industrial buildings, oil and gas pipelines, road surfaces, and even whole towns, the danger of severe damage to infrastructure is growing.

And, the researchers warn, even if the world sticks to its promise, made by 195 nations in Paris in 2015, and contains global warming to no more than 2°C over pre-industrial levels by 2100, there is still a likelihood that the permafrost will disappear over a large area, to surrender more greenhouse gases, and trigger more warming.

“All this data tells us that the permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming, which is producing a substantial warming of the air and increased snow thickness, especially in the Arctic,” said Guido Grosse, who heads permafrost research in Potsdam. “These two factors produce a warming of the once permanently frozen ground.” – Climate News Network

Global warming is at work far below the surface, at depths seemingly insulated from the greenhouse effect. This is bad news for the permafrost.

LONDON, 29 January, 2019 – Even in the coldest places – 10 metres below the surface of the polar wastes – global warming has begun to work. A new study of the frozen soils in both hemispheres shows that between 2007 and 2016, they warmed by an average of 0.3°C.

This remained true within the Arctic and Antarctic zones, in the highest mountain regions of Europe and Asia, and even in the Siberian tundra, where the temperatures at depth rose by almost a whole degree.

New research into the permafrost, defined as territory where soil has been frozen for at least two consecutive years, suggests that much of it may not be permanently frozen for much longer.

Climate scientists have repeatedly warned that along with the tilth, clays and sediments the icy structures store vast amounts of carbon in the form of yet-to-be-decomposed plant material.

So the thawing permafrost could surrender even more warming agents in the form of greenhouse gases, and accelerate global warming even further.

“The permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming”

Researchers based in Potsdam, Germany report in the journal Nature Communications that they and colleagues in the Global Terrestrial Network for Permafrost monitored and measured soil temperatures in boreholes at 154 locations; more than 120 of them over a 10-year cycle. In a dozen locations the temperatures actually fell, and at 40 locations there was virtually no change.

The most dramatic warming was in the Arctic, where soils that were more than 90% permafrost increased temperatures by 0.3°C, and the Siberian north, where temperatures rose by 0.9°C or more. Air temperatures over those regions had risen by an average of 0.6°C in the same decade. In those Arctic regions with less than 90% permafrost, the frozen ground had warmed by 0.2°C.

“In these regions there is more and more snowfall, which insulates the permafrost in two ways, following the igloo principle,” said Boris Biskaborn of the Alfred Wegener Institute, at the Helmholtz Centre for Polar and Marine Research, who led the study.

“In winter snow protects the soil from extreme cold, which on average produces a warming effect. In spring it reflects the sunlight, and prevents the soils from being exposed to too much warmth, at least until the snow has completely melted away.”

Widespread impact

The scientists also report that soil temperature rises were recorded in the Alps of Europe, the mountain ranges of Scandinavia, and in the Himalayas.

Other scientists have already this year identified potential disaster for many settlements in the Arctic regions: the once-hard-frozen topsoils are in danger of thawing, and since these support industrial buildings, oil and gas pipelines, road surfaces, and even whole towns, the danger of severe damage to infrastructure is growing.

And, the researchers warn, even if the world sticks to its promise, made by 195 nations in Paris in 2015, and contains global warming to no more than 2°C over pre-industrial levels by 2100, there is still a likelihood that the permafrost will disappear over a large area, to surrender more greenhouse gases, and trigger more warming.

“All this data tells us that the permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming, which is producing a substantial warming of the air and increased snow thickness, especially in the Arctic,” said Guido Grosse, who heads permafrost research in Potsdam. “These two factors produce a warming of the once permanently frozen ground.” – Climate News Network

Polar ice loss speeds up by leaps and bounds

North and south, polar ice loss is happening faster than ever. Researchers now have a measure of the accelerating flow into the ocean.

LONDON, 22 January, 2019 – In the last few decades the speed of polar ice loss at both ends of the planet has begun to gallop away at rates which will have a marked effect on global sea levels.

Antarctica is now losing ice mass six times faster than it did 40 years ago. In the decade that began in 1979, the great white continent surrendered 40 billion tons of ice a year to raise global sea levels. By the decade 2009 to 2017, this mass loss had soared to 252 billion tons a year.

And in Greenland, the greatest concentration of terrestrial ice in the northern hemisphere has also accelerated its rate of ice loss fourfold in this century.

Satellite studies confirm that in 2003, around 102 billion tons of ice turned to flowing water or broke off into the ocean as floating bergs. By 2013, this figure had climbed to 393 billion tons a year.

“That’s just the tip of the iceberg, so to speak. As the Antarctic Ice Sheet continues to melt away, we expect multi-metre sea level rise from Antarctica in the coming centuries”

Scientists report in the Proceedings of the National Academy of Sciences that they studied high resolution aerial photographs, satellite radar readings and historic Landsat imagery to survey 18 south polar regions encompassing 176 basins and surrounding islands of Antarctica to take the most precise measurement of ice loss so far.

Most of the loss is attributed to the contact with ever-warmer ocean waters as they lap the ice shelves or eat away at grounded glaciers. Since 1979 it has contributed 14mm to global sea level rise. The researchers stress that their reading of the profit-and-loss accounts of polar ice is the longest study so far.

“That’s just the tip of the iceberg, so to speak,” said Eric Rignot, of the University of California Irvine. “As the Antarctic Ice Sheet continues to melt away, we expect multi-metre sea level rise from Antarctica in the coming centuries.” If all the ice on the continent were to melt, it would raise global sea levels by 57 metres.

Growing concern

For more than a decade scientists have been concerned with the rate of warming, the acceleration of glacial flow and the loss of shelf ice off West Antarctica. The latest study indicates that East Antarctica, home to a far greater volume of ice, is also losing mass.

Accelerating glacier movement across Greenland towards the sea has also concerned climate scientists worried about icemelt for years. The island’s bedrock bears a burden of ice sufficient to raise global sea levels by seven metres.

Researchers who have used data from the GRACE satellites – the acronym stands for Gravity Recovery and Climate Experiment – since 2002 also report in the same journal that the largest sustained loss of ice on Greenland came from the island’s southwest. They think that within two decades the region could become a major contributor to global sea level rise. But why the loss has accelerated is uncertain.

“Whichever this was, it couldn’t be explained by glaciers, because there aren’t many there,” said Michael Bevis of Ohio State University. “It had to be surface mass – the ice was melting inland from the coastline.”

Puzzling picture

Once again, warming atmosphere and ocean are linked to ice loss in the Arctic region, a change driven by global warming as a consequence of ever-higher ratios of greenhouse gases in the atmosphere, fed by ever-higher rates of combustion of fossil fuels.

Melting rates have been uneven: the unexplained acceleration between 2003 and 2013 was followed by an equally puzzling pause. Natural atmospheric cycles such as the North Atlantic Oscillation must be part of the explanation.

“These oscillations have been happening forever. So why only now are they causing this massive melt? It is because the atmosphere is, at its baseline, warmer. The transient warming driven by the North Atlantic Oscillation was riding on top of more sustained global warming,” Professor Bevis said.

“We are going to see faster and faster sea level rise for the foreseeable future. Once you hit that tipping point, the only question is: how severe does it get?” – Climate News Network

North and south, polar ice loss is happening faster than ever. Researchers now have a measure of the accelerating flow into the ocean.

LONDON, 22 January, 2019 – In the last few decades the speed of polar ice loss at both ends of the planet has begun to gallop away at rates which will have a marked effect on global sea levels.

Antarctica is now losing ice mass six times faster than it did 40 years ago. In the decade that began in 1979, the great white continent surrendered 40 billion tons of ice a year to raise global sea levels. By the decade 2009 to 2017, this mass loss had soared to 252 billion tons a year.

And in Greenland, the greatest concentration of terrestrial ice in the northern hemisphere has also accelerated its rate of ice loss fourfold in this century.

Satellite studies confirm that in 2003, around 102 billion tons of ice turned to flowing water or broke off into the ocean as floating bergs. By 2013, this figure had climbed to 393 billion tons a year.

“That’s just the tip of the iceberg, so to speak. As the Antarctic Ice Sheet continues to melt away, we expect multi-metre sea level rise from Antarctica in the coming centuries”

Scientists report in the Proceedings of the National Academy of Sciences that they studied high resolution aerial photographs, satellite radar readings and historic Landsat imagery to survey 18 south polar regions encompassing 176 basins and surrounding islands of Antarctica to take the most precise measurement of ice loss so far.

Most of the loss is attributed to the contact with ever-warmer ocean waters as they lap the ice shelves or eat away at grounded glaciers. Since 1979 it has contributed 14mm to global sea level rise. The researchers stress that their reading of the profit-and-loss accounts of polar ice is the longest study so far.

“That’s just the tip of the iceberg, so to speak,” said Eric Rignot, of the University of California Irvine. “As the Antarctic Ice Sheet continues to melt away, we expect multi-metre sea level rise from Antarctica in the coming centuries.” If all the ice on the continent were to melt, it would raise global sea levels by 57 metres.

Growing concern

For more than a decade scientists have been concerned with the rate of warming, the acceleration of glacial flow and the loss of shelf ice off West Antarctica. The latest study indicates that East Antarctica, home to a far greater volume of ice, is also losing mass.

Accelerating glacier movement across Greenland towards the sea has also concerned climate scientists worried about icemelt for years. The island’s bedrock bears a burden of ice sufficient to raise global sea levels by seven metres.

Researchers who have used data from the GRACE satellites – the acronym stands for Gravity Recovery and Climate Experiment – since 2002 also report in the same journal that the largest sustained loss of ice on Greenland came from the island’s southwest. They think that within two decades the region could become a major contributor to global sea level rise. But why the loss has accelerated is uncertain.

“Whichever this was, it couldn’t be explained by glaciers, because there aren’t many there,” said Michael Bevis of Ohio State University. “It had to be surface mass – the ice was melting inland from the coastline.”

Puzzling picture

Once again, warming atmosphere and ocean are linked to ice loss in the Arctic region, a change driven by global warming as a consequence of ever-higher ratios of greenhouse gases in the atmosphere, fed by ever-higher rates of combustion of fossil fuels.

Melting rates have been uneven: the unexplained acceleration between 2003 and 2013 was followed by an equally puzzling pause. Natural atmospheric cycles such as the North Atlantic Oscillation must be part of the explanation.

“These oscillations have been happening forever. So why only now are they causing this massive melt? It is because the atmosphere is, at its baseline, warmer. The transient warming driven by the North Atlantic Oscillation was riding on top of more sustained global warming,” Professor Bevis said.

“We are going to see faster and faster sea level rise for the foreseeable future. Once you hit that tipping point, the only question is: how severe does it get?” – Climate News Network

Underwater walls might avert sea level rise

Could a vast underwater wall in front of an unstable glacier prevent dangerous sea level rise? Or should everyone just move further inland?

LONDON, 10 October, 2018 – Two climate scientists believe they have a long-term solution to dangerous sea level rise by targeting the most vulnerable glaciers, especially those that could trigger a massive collapse of the ice sheets behind them.

A submarine wall big enough and wide enough could halt the flow of increasingly warm ocean water below the front of each glacier. The combination of warmer air temperatures and warmer waters that accompany human-triggered climate change is dangerous: it could for instance accelerate the already alarming retreat of the Thwaites Glacier in West Antarctica, which alone shores up enough ice to raise global sea levels by up to 3 metres.

The scientists don’t propose an immediate start. But they do want to explore ways of halting sea level rise driven by global warming that could soon be costing the world $50 trillion a year in economic losses, that could submerge small island states and turn 1 million people a year into climate migrants.

“We are not advocating that glacial geoengineering be attempted any time soon”, they warn in the journal The Cryosphere.

Their simplest option – a series of pillars to shore up a targeted glacier and keep it “grounded” – would require engineering comparable in scale to the excavation of the Suez canal, would be undertaken in the world’s harshest environment, and would have just a one in three chance of success.

“In the long run we need plans to deal with the committed climate changes that are already in the pipeline, one of which may be an ice sheet collapse”

The researchers – John Moore, of Beijing Normal University in China, who also holds a post at the University of Lapland in Finland, and Michael Wolovick, of Princeton University in the US – have made this case before: they and others argued in March in Nature for what they call “managed collapse.”

In the latest study, they look at the challenge in greater detail. And they warn that even if targeted geoengineering of individual glaciers worked, it would only do so if humans stopped tipping ever more greenhouse gases into the atmosphere to fuel yet more global warming.

Nor do they argue that a submarine curtain wall to halt warming water across the front of the Thwaites glacier – up to 100 kms wide – is currently feasible. “But in the long run we need plans to deal with the committed climate changes that are already in the pipeline, one of which may be an ice sheet collapse.”

And one of these is the Thwaites Glacier in Antarctica: another is the Jakobshaven Isbrae in Greenland. Both could be cases of what the scientists call marine ice sheet instability: as a glacier retreats from its grounding line, the ice lifts off the bedrock and begins to float.

If the bedrock slopes down towards the centre of the ice sheet, and warmer ocean currents wash beneath it, then the ice starts to stretch and thin, and retreat further. At some point, it would become much easier for thawing ice to flow into the sea, and start what could become a runaway collapse. Engineers could devise a way of slowing or halting the process.

Huge impact

The scientists argue that even a rise of 0.6m to 1.2 metres by 2100 could cause up to $50 trillion in economic damage, and the resultant flooding could force up to 200 million to 500 million people out of their homes at least for a few days or weeks: around a million or so every year would never go back.

Climate scientists have been arguing about geoengineering solutions – the so-called technofix – to climate change for more than a decade. Global answers, such as blocking sunlight with stratospheric soot and sulphate aerosols, or whitening the polar ice to make it more reflective, remain contentious.

But the Cryosphere proposals are much more limited, and the immediate dangers of sea level rise are not contested. Ice sheet collapse in Antarctica, for instance, could raise sea levels by more than 3 metres and even by as much as 19 metres over the next two or three centuries.

The researchers’ calculations suggest that in theory an engineering solution that blocked even 50% of the warm water getting under a glacier could offer a 70% chance of delaying or stopping ice sheet collapse.

Left behind

Countries already spend on coastal protection: their solution would require international co-operation at the highest political level, and intensive scientific research.

“Managing sea level rise at the source has the advantage of benefiting the entire world, while a strategy that relies only on local coastal protection is more of an every-nation-for-itself approach that may leave many poor countries behind,” they write.

“Perhaps, after careful consideration, we may conclude that glacial geoengineering is unworkable and the right answer is to invest heavily in coastal protection and retreat inland where that is not practical or economical.

“However, we owe it to the 400 million people who live within 5m of sea level to at least consider the alternatives.” – Climate News Network

Could a vast underwater wall in front of an unstable glacier prevent dangerous sea level rise? Or should everyone just move further inland?

LONDON, 10 October, 2018 – Two climate scientists believe they have a long-term solution to dangerous sea level rise by targeting the most vulnerable glaciers, especially those that could trigger a massive collapse of the ice sheets behind them.

A submarine wall big enough and wide enough could halt the flow of increasingly warm ocean water below the front of each glacier. The combination of warmer air temperatures and warmer waters that accompany human-triggered climate change is dangerous: it could for instance accelerate the already alarming retreat of the Thwaites Glacier in West Antarctica, which alone shores up enough ice to raise global sea levels by up to 3 metres.

The scientists don’t propose an immediate start. But they do want to explore ways of halting sea level rise driven by global warming that could soon be costing the world $50 trillion a year in economic losses, that could submerge small island states and turn 1 million people a year into climate migrants.

“We are not advocating that glacial geoengineering be attempted any time soon”, they warn in the journal The Cryosphere.

Their simplest option – a series of pillars to shore up a targeted glacier and keep it “grounded” – would require engineering comparable in scale to the excavation of the Suez canal, would be undertaken in the world’s harshest environment, and would have just a one in three chance of success.

“In the long run we need plans to deal with the committed climate changes that are already in the pipeline, one of which may be an ice sheet collapse”

The researchers – John Moore, of Beijing Normal University in China, who also holds a post at the University of Lapland in Finland, and Michael Wolovick, of Princeton University in the US – have made this case before: they and others argued in March in Nature for what they call “managed collapse.”

In the latest study, they look at the challenge in greater detail. And they warn that even if targeted geoengineering of individual glaciers worked, it would only do so if humans stopped tipping ever more greenhouse gases into the atmosphere to fuel yet more global warming.

Nor do they argue that a submarine curtain wall to halt warming water across the front of the Thwaites glacier – up to 100 kms wide – is currently feasible. “But in the long run we need plans to deal with the committed climate changes that are already in the pipeline, one of which may be an ice sheet collapse.”

And one of these is the Thwaites Glacier in Antarctica: another is the Jakobshaven Isbrae in Greenland. Both could be cases of what the scientists call marine ice sheet instability: as a glacier retreats from its grounding line, the ice lifts off the bedrock and begins to float.

If the bedrock slopes down towards the centre of the ice sheet, and warmer ocean currents wash beneath it, then the ice starts to stretch and thin, and retreat further. At some point, it would become much easier for thawing ice to flow into the sea, and start what could become a runaway collapse. Engineers could devise a way of slowing or halting the process.

Huge impact

The scientists argue that even a rise of 0.6m to 1.2 metres by 2100 could cause up to $50 trillion in economic damage, and the resultant flooding could force up to 200 million to 500 million people out of their homes at least for a few days or weeks: around a million or so every year would never go back.

Climate scientists have been arguing about geoengineering solutions – the so-called technofix – to climate change for more than a decade. Global answers, such as blocking sunlight with stratospheric soot and sulphate aerosols, or whitening the polar ice to make it more reflective, remain contentious.

But the Cryosphere proposals are much more limited, and the immediate dangers of sea level rise are not contested. Ice sheet collapse in Antarctica, for instance, could raise sea levels by more than 3 metres and even by as much as 19 metres over the next two or three centuries.

The researchers’ calculations suggest that in theory an engineering solution that blocked even 50% of the warm water getting under a glacier could offer a 70% chance of delaying or stopping ice sheet collapse.

Left behind

Countries already spend on coastal protection: their solution would require international co-operation at the highest political level, and intensive scientific research.

“Managing sea level rise at the source has the advantage of benefiting the entire world, while a strategy that relies only on local coastal protection is more of an every-nation-for-itself approach that may leave many poor countries behind,” they write.

“Perhaps, after careful consideration, we may conclude that glacial geoengineering is unworkable and the right answer is to invest heavily in coastal protection and retreat inland where that is not practical or economical.

“However, we owe it to the 400 million people who live within 5m of sea level to at least consider the alternatives.” – Climate News Network

Frozen Arctic moves seawards in hectic melt

Once trapped in a Russian ice cap north of Siberia, the frozen Arctic is moving fast, racing in decades from metres to kilometres a year.

LONDON, 5 October, 2018 – Satellite images have revealed a dramatic change in Russia’s frozen Arctic. An ice cap that once crept almost imperceptibly across the barren rocks of October Revolution island, in the Kara Sea, is on the move.

All ice, even when permanently frozen to the bedrock, moves. From 1952 to 1985, the western edge of the Vavilov ice cap, 1,820 square kilometres in area and between 300 metres and 600 metres in thickness, shifted at about 12 metres a year. Between 1998 and 2011, it stepped up the pace to 75 metres a year. Between 2014 and 2015, the ice front had broken into tongues that moved at more than 1,000 metres a year.

And between 2015 and 2016 the leading edge had started racing into the Kara Sea at 5,000 metres a year. It is also thinning at the rate of a third of a metre a day, according to a new study in the journal Earth and Planetary Science Letters.

The high Arctic is the fastest-warming place on Earth, and researchers have for more than 30 years been measuring changes in the rate at which sea ice shrinks and Greenland glaciers flow.

Role as metaphor

“In a warming climate, glacier acceleration is becoming more and more common, but the rate of ice loss at Vavilov is extreme and unexpected,” said Michael Willis, a geologist at the University of California Boulder, who led the study by scientists from the US, UK and Russia.

Glaciers and icecaps such as Vavilov cover about 450,000 square kilometres of the planet’s surface and hold enough frozen water to raise global sea levels by 30 cms. They form on land in polar “deserts” in which the temperatures are below freezing and snow falls at no more than 25 cms a year.

In the Arctic summer the snow cover melts, and water trickles down through the ice; over the years, snowfall patterns shift and the ice cap shifts under gravitational tug. All glaciers flow, but so slowly that their pace has been incorporated into metaphor.

For the study authors, who used decades of satellite studies of the high Arctic to measure the change, the puzzle is one of geophysics: how could a fast-frozen mass of ice get to the stage where it can slide, as if lubricated, across a rocky surface above sea level?

“Glacier acceleration is becoming more and more common, but the rate of ice loss at Vavilov is extreme and unexpected”

“We’ve never seen anything like this before, this study has raised as many questions as it has answered,” said Dr Willis. “And we’re now working on modelling the whole situation to get a better handle on the physics involved.”

But for climate scientists concerned with the bigger picture, the study is another instance of potentially catastrophic climate change in the making. Once an ice cap starts to flow, the process is unlikely to stop.

And a second study in the same week from the other end of the globe shows that it doesn’t take much to start the ice flowing into the sea. It has confirmed that average global warming of no more than 2°C above historic levels, given long enough,  could melt much of the world’s largest ice sheet.

Planetary average temperatures have already risen by 1°C since the first industrial exploitation of coal, gas and oil only 200 years ago, and right now, although 195 nations vowed in Paris in 2015 to keep the rise to “well below” 2°C by 2100, the world seems headed for at least a 3°C rise later this century.

Future loss inevitable

British, Australian, New Zealand, Spanish and Japanese scientists report in Nature that they reconstructed the impact of change on the East Antarctic ice sheet during interglacials, those warm pauses during the last Ice Age.

For about 2,500 years, Antarctic air temperatures rose by about 2°C, the huge fastness of ice began to melt, and sea levels rose. The West Antarctic ice sheet, which has repeatedly shown signs of thawing, holds enough water to raise sea levels by up to 5 metres. The apparently stable East Antarctic sheet holds enough to lift global sea levels by 53 metres. During the interglacials of 400,000 years ago and 125,000 years ago, sea levels rose between 6 metres and 13 metres higher than they are today.

“What we have learned is that even modest warming of just two degrees, if sustained for a couple of thousand years, is enough to cause the East Antarctic ice sheet to retreat in some of its low-lying areas,” said David Wilson, of the UK’s Imperial College, who led the research.

“With current global temperatures already one degree higher than during pre-industrial times, future ice loss seems inevitable if we fail to reduce carbon emissions.” – Climate News Network

Once trapped in a Russian ice cap north of Siberia, the frozen Arctic is moving fast, racing in decades from metres to kilometres a year.

LONDON, 5 October, 2018 – Satellite images have revealed a dramatic change in Russia’s frozen Arctic. An ice cap that once crept almost imperceptibly across the barren rocks of October Revolution island, in the Kara Sea, is on the move.

All ice, even when permanently frozen to the bedrock, moves. From 1952 to 1985, the western edge of the Vavilov ice cap, 1,820 square kilometres in area and between 300 metres and 600 metres in thickness, shifted at about 12 metres a year. Between 1998 and 2011, it stepped up the pace to 75 metres a year. Between 2014 and 2015, the ice front had broken into tongues that moved at more than 1,000 metres a year.

And between 2015 and 2016 the leading edge had started racing into the Kara Sea at 5,000 metres a year. It is also thinning at the rate of a third of a metre a day, according to a new study in the journal Earth and Planetary Science Letters.

The high Arctic is the fastest-warming place on Earth, and researchers have for more than 30 years been measuring changes in the rate at which sea ice shrinks and Greenland glaciers flow.

Role as metaphor

“In a warming climate, glacier acceleration is becoming more and more common, but the rate of ice loss at Vavilov is extreme and unexpected,” said Michael Willis, a geologist at the University of California Boulder, who led the study by scientists from the US, UK and Russia.

Glaciers and icecaps such as Vavilov cover about 450,000 square kilometres of the planet’s surface and hold enough frozen water to raise global sea levels by 30 cms. They form on land in polar “deserts” in which the temperatures are below freezing and snow falls at no more than 25 cms a year.

In the Arctic summer the snow cover melts, and water trickles down through the ice; over the years, snowfall patterns shift and the ice cap shifts under gravitational tug. All glaciers flow, but so slowly that their pace has been incorporated into metaphor.

For the study authors, who used decades of satellite studies of the high Arctic to measure the change, the puzzle is one of geophysics: how could a fast-frozen mass of ice get to the stage where it can slide, as if lubricated, across a rocky surface above sea level?

“Glacier acceleration is becoming more and more common, but the rate of ice loss at Vavilov is extreme and unexpected”

“We’ve never seen anything like this before, this study has raised as many questions as it has answered,” said Dr Willis. “And we’re now working on modelling the whole situation to get a better handle on the physics involved.”

But for climate scientists concerned with the bigger picture, the study is another instance of potentially catastrophic climate change in the making. Once an ice cap starts to flow, the process is unlikely to stop.

And a second study in the same week from the other end of the globe shows that it doesn’t take much to start the ice flowing into the sea. It has confirmed that average global warming of no more than 2°C above historic levels, given long enough,  could melt much of the world’s largest ice sheet.

Planetary average temperatures have already risen by 1°C since the first industrial exploitation of coal, gas and oil only 200 years ago, and right now, although 195 nations vowed in Paris in 2015 to keep the rise to “well below” 2°C by 2100, the world seems headed for at least a 3°C rise later this century.

Future loss inevitable

British, Australian, New Zealand, Spanish and Japanese scientists report in Nature that they reconstructed the impact of change on the East Antarctic ice sheet during interglacials, those warm pauses during the last Ice Age.

For about 2,500 years, Antarctic air temperatures rose by about 2°C, the huge fastness of ice began to melt, and sea levels rose. The West Antarctic ice sheet, which has repeatedly shown signs of thawing, holds enough water to raise sea levels by up to 5 metres. The apparently stable East Antarctic sheet holds enough to lift global sea levels by 53 metres. During the interglacials of 400,000 years ago and 125,000 years ago, sea levels rose between 6 metres and 13 metres higher than they are today.

“What we have learned is that even modest warming of just two degrees, if sustained for a couple of thousand years, is enough to cause the East Antarctic ice sheet to retreat in some of its low-lying areas,” said David Wilson, of the UK’s Imperial College, who led the research.

“With current global temperatures already one degree higher than during pre-industrial times, future ice loss seems inevitable if we fail to reduce carbon emissions.” – Climate News Network

Warming climate leaves its varied marks

The warming climate is changing the globe: mountain species climb higher, valley floors sink and animal numbers fall, while their living space shrinks.

LONDON, 28 September, 2018 – The Earth’s warming climate is already reshaping the planet. A new study confirms that plants and animals unique to the mountains are climbing ever higher to survive.

A second research team has taken a closer look at the valley floors of Central California to find that one of them is now, thanks to drought conditions, sinking by up to half a metre a year.

In central and eastern Europe, German scientists have found that the Danube – on which people used to skate every winter – has frozen only a handful of times in the last 70 years.

And far to the south, French scientists report that one of the world’s largest colonies of king penguins has dwindled by 88% since 1982.

In all cases, researchers identify a possible environmental cause: and in all cases the changes could be linked to global warming. In three instances out of four, climate change has already been implicated by other studies.

“The scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill”

Years ago, Swiss scientists observed a steady uphill migration of alpine butterflies and birds; while US scientists have charted change in mountain flora in the Rockies and Danish scientists revisited an Andean mountain first explored by the great Alexander von Humboldt to find that the plants he recorded had climbed 500 metres in 210 years.

Now Canadian scientists report in the journal Global Ecology and Biogeography that they set themselves the challenge of the global picture: they reviewed studies of elevation shifts in 975 species of plant, insect and animal.

In the French Pyrenees, the mountain burnet butterfly has shifted uphill by 430 metres and surrendered 79% of its range. In the Himalayas, where temperatures have risen by 2.2°C in 150 years, one meadow flower has migrated more than 600 metres and lost 28% of its preferred habitat. In Nevada’s Ruby Mountains, the northern pocket gopher has responded to a warming of 1.1°C in 80 years by climbing higher and surrendering 70% of its living room.

Altogether, the scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill.

In the mountains of California, the peaks are getting ever higher because the reduced mass of snowfall no longer depresses the rock.

Sinking feeling

Paradoxically, thanks to the combination of sustained drought and relentless abstraction of groundwater for agriculture, things are going downhill in the San Joaquin valley of California,, according to scientists from Cornell University who report in the journal Science Advances. The valley is home to 75% of California’s irrigated farmland. It supplies 8% of US agricultural output and it has a long record of slow subsidence.

The Cornell scientists report that between 1962 and 2011, the valley lost groundwater at the rate of 1.85 cubic kilometres a year. Between 2012 and 2016, during the state’s worst-ever drought, the same basin lost 40 cubic kilometres of groundwater, and the ground fell at 50 cms a year, except for a slowdown in subsidence during the heavy rains of 2017. The previous rate of subsidence has resumed.

The Danube Commission has kept records since 1836 of the behaviour of Europe’s second largest river as it flows from the Alps to the Black Sea. Researchers from Germany’s Alfred Wegener Institute write in the journal Scientific Reports that archivists reported ice cover almost every year, ice thick enough to bear skaters.

But between 1951 and 2016, the river froze only 10 times. Although more people live in Europe than ever before, and discharge more outflow into the Danube basin, the researchers identify global warming as a substantial cause: winter temperatures have risen and are now more than 1.0°C warmer than in the first half of the 20th century.

Problems for penguins

And rising temperatures might be at the heart of the crisis for king penguins on the Iles Crozet archipelago in Antarctica: French scientists report in the journal Antarctic Science that in 1982 the colony was home to 500,000 breeding pairs and two million specimens of Aptenodytes patagonicus.

Now the colony has shrunk, and vegetation cover has expanded. The loss might be linked to lack of food, or a major natural warming event such as El Nino, or to disease such as avian cholera.

But global warming and climate change have already been linked to alarms over the king penguin elsewhere, and to the possible fate of the emperor penguin.

The research is based on aerial imagery and satellite studies, and on-the-ground research is still needed to explain quite why a colony which once supported 500,000 breeding pairs should now number only 60,000 penguin couples.

“The cause of the massive decline of the colony remains a mystery, and needs to be resolved,” the French scientists say. – Climate News Network

The warming climate is changing the globe: mountain species climb higher, valley floors sink and animal numbers fall, while their living space shrinks.

LONDON, 28 September, 2018 – The Earth’s warming climate is already reshaping the planet. A new study confirms that plants and animals unique to the mountains are climbing ever higher to survive.

A second research team has taken a closer look at the valley floors of Central California to find that one of them is now, thanks to drought conditions, sinking by up to half a metre a year.

In central and eastern Europe, German scientists have found that the Danube – on which people used to skate every winter – has frozen only a handful of times in the last 70 years.

And far to the south, French scientists report that one of the world’s largest colonies of king penguins has dwindled by 88% since 1982.

In all cases, researchers identify a possible environmental cause: and in all cases the changes could be linked to global warming. In three instances out of four, climate change has already been implicated by other studies.

“The scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill”

Years ago, Swiss scientists observed a steady uphill migration of alpine butterflies and birds; while US scientists have charted change in mountain flora in the Rockies and Danish scientists revisited an Andean mountain first explored by the great Alexander von Humboldt to find that the plants he recorded had climbed 500 metres in 210 years.

Now Canadian scientists report in the journal Global Ecology and Biogeography that they set themselves the challenge of the global picture: they reviewed studies of elevation shifts in 975 species of plant, insect and animal.

In the French Pyrenees, the mountain burnet butterfly has shifted uphill by 430 metres and surrendered 79% of its range. In the Himalayas, where temperatures have risen by 2.2°C in 150 years, one meadow flower has migrated more than 600 metres and lost 28% of its preferred habitat. In Nevada’s Ruby Mountains, the northern pocket gopher has responded to a warming of 1.1°C in 80 years by climbing higher and surrendering 70% of its living room.

Altogether, the scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill.

In the mountains of California, the peaks are getting ever higher because the reduced mass of snowfall no longer depresses the rock.

Sinking feeling

Paradoxically, thanks to the combination of sustained drought and relentless abstraction of groundwater for agriculture, things are going downhill in the San Joaquin valley of California,, according to scientists from Cornell University who report in the journal Science Advances. The valley is home to 75% of California’s irrigated farmland. It supplies 8% of US agricultural output and it has a long record of slow subsidence.

The Cornell scientists report that between 1962 and 2011, the valley lost groundwater at the rate of 1.85 cubic kilometres a year. Between 2012 and 2016, during the state’s worst-ever drought, the same basin lost 40 cubic kilometres of groundwater, and the ground fell at 50 cms a year, except for a slowdown in subsidence during the heavy rains of 2017. The previous rate of subsidence has resumed.

The Danube Commission has kept records since 1836 of the behaviour of Europe’s second largest river as it flows from the Alps to the Black Sea. Researchers from Germany’s Alfred Wegener Institute write in the journal Scientific Reports that archivists reported ice cover almost every year, ice thick enough to bear skaters.

But between 1951 and 2016, the river froze only 10 times. Although more people live in Europe than ever before, and discharge more outflow into the Danube basin, the researchers identify global warming as a substantial cause: winter temperatures have risen and are now more than 1.0°C warmer than in the first half of the 20th century.

Problems for penguins

And rising temperatures might be at the heart of the crisis for king penguins on the Iles Crozet archipelago in Antarctica: French scientists report in the journal Antarctic Science that in 1982 the colony was home to 500,000 breeding pairs and two million specimens of Aptenodytes patagonicus.

Now the colony has shrunk, and vegetation cover has expanded. The loss might be linked to lack of food, or a major natural warming event such as El Nino, or to disease such as avian cholera.

But global warming and climate change have already been linked to alarms over the king penguin elsewhere, and to the possible fate of the emperor penguin.

The research is based on aerial imagery and satellite studies, and on-the-ground research is still needed to explain quite why a colony which once supported 500,000 breeding pairs should now number only 60,000 penguin couples.

“The cause of the massive decline of the colony remains a mystery, and needs to be resolved,” the French scientists say. – Climate News Network

Hothouse Earth could soon be unavoidable

Researchers say the world may be approaching a tipping point, followed by a dangerous slide towards Hothouse Earth, an overheated planet.

LONDON, 7 August, 2018 – Human actions threaten to push the planet into a new state, called Hothouse Earth. In such a world global average temperatures could stabilise at 4°C or even 5°C higher than they have been for most of human history.

Global sea levels, too, would rise, by 10 metres, or even as much as 60 metres, to drown all the world’s great coastal cities. Such a transition might happen “in only a century or two”, but once started, there might be no stopping it.

It would be uncontrollable and dangerous to many and “it poses severe risks for health, economies, political stability … and ultimately the habitability of the planet for humans.”

And, say scientists who have completed a survey of the research landscape, there is no knowing how close the threshold of dramatic change might be. The planet has already warmed by 1°C in the last century, and the thermometer is climbing at a rate of 0.17°C per decade.

Even at the ambitious target temperature rise of no more than 2°C by the end of the century – a target endorsed by 195 nations in Paris in 2015 – humans might already have triggered a cascade of feedbacks that would set the planet sliding to a point hotter than at any time in the last 10 million years.

“These tipping elements can potentially act like a row of dominoes. Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over”

Researchers, led by Will Steffen of the Australian National University and backed by some of the big names of European climate science, report in the Proceedings of the National Academy of Sciences that they considered 10 natural processes, among them a number of tipping points that could lead to change once a certain temperature threshold had been crossed.

These feedbacks could turn what are, right now, carbon sinks – stores of atmospheric carbon locked away in the soils and the forests – into sources of greenhouse gases that could accelerate global warming.

These future hazards include thawing of the permafrost, the loss of methane hydrates stored in the ocean floor, the weakening of carbon stores both on land and in the oceans, increasing bacterial activity in the seas, dieback in the tropical Amazon forest and in the cool forests of the north, the loss of sea ice in the Arctic summer, and the loss of Antarctic sea ice and the polar ice sheets.

“These tipping elements can potentially act like a row of dominoes. Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over. Places on Earth will become uninhabitable if ‘Hothouse Earth’ becomes a reality,” said Johan Rockström, of the Stockholm Resilience Centre.

Losing balance

And a co-author, Hans Joachim Schellnhuber, who directs the Potsdam Institute for Climate Impact Research, said: “We show how industrial age greenhouse gas emissions force our climate, and ultimately the Earth system, out of balance.

“In particular, we address tipping elements in the planetary machinery that might, once a certain level has been passed, one by one change fundamentally rapidly, and perhaps irreversibly. The cascade of events may tip the entire Earth system into a new mode of operation.”

The message, although alarming, is a restatement of previous findings and a reconsideration of existing evidence, enhanced by lessons from the more recent geological past, in which rocks and the fossils buried with them tell a story of dramatic changes in temperature and sea level.

Other researchers have raised the hazard of “tipping points” that could send the climate into a state of irreversible change. Professor Steffen three years ago warned that of the nine safe “planetary boundaries” that kept Earth in a stable climate state, four had already been crossed.

Potsdam scientists have already proposed that human release of greenhouse gases – the consequence of profligate use of fossil fuels – has now lifted the Earth from its million year cycle of Ice Ages and interglacials into a new stabilised state, known variously as the  Anthropocene and “the Deglacial.” And Stockholm scientists have joined them in warning that there are more uncertainties and climate stresses to come.

Planetary threshold

The new study however re-examines the possibilities and once again spells out the dangers in language of uncompromising clarity. “The Earth system may be approaching a planetary threshold that could lock in a continuing rapid pathway toward much hotter conditions – Hothouse Earth.

“This pathway would be propelled by strong, intrinsic, biogeophysical feedbacks difficult to influence by human actions, a pathway that could not be reversed, steered or substantially slowed.”

And, the authors warn, the impact on human society would be “massive, sometimes abrupt and undoubtedly disruptive.”

But, of course, nobody knows at what point such a dangerous slide into a new temperature zone could become inexorable, and the researchers make this clear.

“What we do not know is whether the climate system can be safely ‘parked’ near 2°C above preindustrial levels, as the Paris Agreement envisages,” said Professor Schellnhuber, “or if it will, once pushed so far, slip down the slope towards a hothouse planet. Research must assess this risk as soon as possible.” – Climate News Network

Researchers say the world may be approaching a tipping point, followed by a dangerous slide towards Hothouse Earth, an overheated planet.

LONDON, 7 August, 2018 – Human actions threaten to push the planet into a new state, called Hothouse Earth. In such a world global average temperatures could stabilise at 4°C or even 5°C higher than they have been for most of human history.

Global sea levels, too, would rise, by 10 metres, or even as much as 60 metres, to drown all the world’s great coastal cities. Such a transition might happen “in only a century or two”, but once started, there might be no stopping it.

It would be uncontrollable and dangerous to many and “it poses severe risks for health, economies, political stability … and ultimately the habitability of the planet for humans.”

And, say scientists who have completed a survey of the research landscape, there is no knowing how close the threshold of dramatic change might be. The planet has already warmed by 1°C in the last century, and the thermometer is climbing at a rate of 0.17°C per decade.

Even at the ambitious target temperature rise of no more than 2°C by the end of the century – a target endorsed by 195 nations in Paris in 2015 – humans might already have triggered a cascade of feedbacks that would set the planet sliding to a point hotter than at any time in the last 10 million years.

“These tipping elements can potentially act like a row of dominoes. Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over”

Researchers, led by Will Steffen of the Australian National University and backed by some of the big names of European climate science, report in the Proceedings of the National Academy of Sciences that they considered 10 natural processes, among them a number of tipping points that could lead to change once a certain temperature threshold had been crossed.

These feedbacks could turn what are, right now, carbon sinks – stores of atmospheric carbon locked away in the soils and the forests – into sources of greenhouse gases that could accelerate global warming.

These future hazards include thawing of the permafrost, the loss of methane hydrates stored in the ocean floor, the weakening of carbon stores both on land and in the oceans, increasing bacterial activity in the seas, dieback in the tropical Amazon forest and in the cool forests of the north, the loss of sea ice in the Arctic summer, and the loss of Antarctic sea ice and the polar ice sheets.

“These tipping elements can potentially act like a row of dominoes. Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over. Places on Earth will become uninhabitable if ‘Hothouse Earth’ becomes a reality,” said Johan Rockström, of the Stockholm Resilience Centre.

Losing balance

And a co-author, Hans Joachim Schellnhuber, who directs the Potsdam Institute for Climate Impact Research, said: “We show how industrial age greenhouse gas emissions force our climate, and ultimately the Earth system, out of balance.

“In particular, we address tipping elements in the planetary machinery that might, once a certain level has been passed, one by one change fundamentally rapidly, and perhaps irreversibly. The cascade of events may tip the entire Earth system into a new mode of operation.”

The message, although alarming, is a restatement of previous findings and a reconsideration of existing evidence, enhanced by lessons from the more recent geological past, in which rocks and the fossils buried with them tell a story of dramatic changes in temperature and sea level.

Other researchers have raised the hazard of “tipping points” that could send the climate into a state of irreversible change. Professor Steffen three years ago warned that of the nine safe “planetary boundaries” that kept Earth in a stable climate state, four had already been crossed.

Potsdam scientists have already proposed that human release of greenhouse gases – the consequence of profligate use of fossil fuels – has now lifted the Earth from its million year cycle of Ice Ages and interglacials into a new stabilised state, known variously as the  Anthropocene and “the Deglacial.” And Stockholm scientists have joined them in warning that there are more uncertainties and climate stresses to come.

Planetary threshold

The new study however re-examines the possibilities and once again spells out the dangers in language of uncompromising clarity. “The Earth system may be approaching a planetary threshold that could lock in a continuing rapid pathway toward much hotter conditions – Hothouse Earth.

“This pathway would be propelled by strong, intrinsic, biogeophysical feedbacks difficult to influence by human actions, a pathway that could not be reversed, steered or substantially slowed.”

And, the authors warn, the impact on human society would be “massive, sometimes abrupt and undoubtedly disruptive.”

But, of course, nobody knows at what point such a dangerous slide into a new temperature zone could become inexorable, and the researchers make this clear.

“What we do not know is whether the climate system can be safely ‘parked’ near 2°C above preindustrial levels, as the Paris Agreement envisages,” said Professor Schellnhuber, “or if it will, once pushed so far, slip down the slope towards a hothouse planet. Research must assess this risk as soon as possible.” – Climate News Network

Alien seaweed arrives in Antarctica

For more than a century, scientists believed that only humans could cross the hostile oceans to reach Antarctica. Some strands of alien seaweed tell another story.

LONDON, 19 July, 2018 – A foreign invader, a species of alien seaweed, has managed to cross the oceans to reach the frozen Antarctic shores. So scientists may have to give up a cherished belief: that Antarctica is inviolate.

For a century, researchers have assumed that the mix of ocean currents, distance and temperature have kept the Great White Continent shielded from invasion by Pacific or Atlantic flotsam.

But the discovery of strands of kelp on an Antarctic beach – seaweed that may have drifted for considerable periods and a distance of 20,000 kms before becoming stranded far from home – brings an end to that belief. And the discovery suggests that global warming could bring serious changes to Antarctic ecosystems.

“Our findings also indicate that plants and animals living on Antarctica could be more vulnerable to climate change than we suspected”

“This finding shows us that living plants and animals can reach Antarctica across the ocean, with temperate and sub-Antarctic marine species probably bombarding Antarctic coastlines all the time,” said Ceridwen Fraser, of the Australian National University.

“We always thought Antarctic plants and animals were distinct because they were isolated, but this research now suggests these differences are almost entirely due to environmental extremes, not isolation.”

Dr Fraser and her colleagues report in the journal Nature Climate Change that strands of southern bull kelp, Durvillaea antarctica, found by a Chilean scientist, must have floated 20,000 km from the Kerguelen Islands and South Georgia. The kelp was encrusted with barnacles, evidence of a long time adrift.

In fact, researchers believe, it may be evidence of the longest episode of “biological rafting” ever confirmed. The word raft is significant: such floating platforms could provide shelter and transport for other biological invaders.

Plastic next?

Until now, the assumption has been that the pattern of surface currents and westerly winds tends to drive drifting material northwards from Antarctica. The discovery suggests that if kelp can get there, so can floating driftwood, or plastic debris, or any other unwelcome visitor.

The researchers think large waves driven by Southern Ocean storms may have steered the kelp rafts over what had been considered a natural ocean barrier. Global warming has begun to change conditions in Antarctica, and the continent – considered the last great tract of terrain unmarked by human colonisation – could become increasingly vulnerable to change.

“This is an unequivocal demonstration that marine species from the north can reach Antarctica. To get there the kelp had to pass through barriers created by polar winds and currents that were, until now, thought to be impenetrable,” Dr Fraser said.

“Our findings also indicate that plants and animals living on Antarctica could be more vulnerable to climate change than we suspected.” – Climate News Network

For more than a century, scientists believed that only humans could cross the hostile oceans to reach Antarctica. Some strands of alien seaweed tell another story.

LONDON, 19 July, 2018 – A foreign invader, a species of alien seaweed, has managed to cross the oceans to reach the frozen Antarctic shores. So scientists may have to give up a cherished belief: that Antarctica is inviolate.

For a century, researchers have assumed that the mix of ocean currents, distance and temperature have kept the Great White Continent shielded from invasion by Pacific or Atlantic flotsam.

But the discovery of strands of kelp on an Antarctic beach – seaweed that may have drifted for considerable periods and a distance of 20,000 kms before becoming stranded far from home – brings an end to that belief. And the discovery suggests that global warming could bring serious changes to Antarctic ecosystems.

“Our findings also indicate that plants and animals living on Antarctica could be more vulnerable to climate change than we suspected”

“This finding shows us that living plants and animals can reach Antarctica across the ocean, with temperate and sub-Antarctic marine species probably bombarding Antarctic coastlines all the time,” said Ceridwen Fraser, of the Australian National University.

“We always thought Antarctic plants and animals were distinct because they were isolated, but this research now suggests these differences are almost entirely due to environmental extremes, not isolation.”

Dr Fraser and her colleagues report in the journal Nature Climate Change that strands of southern bull kelp, Durvillaea antarctica, found by a Chilean scientist, must have floated 20,000 km from the Kerguelen Islands and South Georgia. The kelp was encrusted with barnacles, evidence of a long time adrift.

In fact, researchers believe, it may be evidence of the longest episode of “biological rafting” ever confirmed. The word raft is significant: such floating platforms could provide shelter and transport for other biological invaders.

Plastic next?

Until now, the assumption has been that the pattern of surface currents and westerly winds tends to drive drifting material northwards from Antarctica. The discovery suggests that if kelp can get there, so can floating driftwood, or plastic debris, or any other unwelcome visitor.

The researchers think large waves driven by Southern Ocean storms may have steered the kelp rafts over what had been considered a natural ocean barrier. Global warming has begun to change conditions in Antarctica, and the continent – considered the last great tract of terrain unmarked by human colonisation – could become increasingly vulnerable to change.

“This is an unequivocal demonstration that marine species from the north can reach Antarctica. To get there the kelp had to pass through barriers created by polar winds and currents that were, until now, thought to be impenetrable,” Dr Fraser said.

“Our findings also indicate that plants and animals living on Antarctica could be more vulnerable to climate change than we suspected.” – Climate News Network