Tag Archives: Ice melt

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

Permafrost thaw unsettles the Arctic

Permafrost thaw and retreating Arctic ice don’t just imperil caribou and bears. People, too, may find the ground shifts beneath their feet.

LONDON, 1 January, 2019 − In just one human generation, citizens of the far north could find themselves on shifting soils as the region’s permafrost thaws. Roads will slump. Buildings will buckle. Pipelines will become at risk of fracture. And in 2050, around three fourths of the people of the permafrost could watch their infrastructure collapse, as what was once hard frozen ground turns into mud.

All this could happen even if the world keeps the promise it made in Paris in 2015 and limits global average warming to just 1.5°C above the level for most of pre-industrial history.

In the last century, the world has already warmed by 1°C on average: the Arctic region has warmed at a far faster rate. At present rates of warming, driven by the profligate use of fossil fuels that raise the levels of greenhouse gases in the atmosphere, the world is on course for an average warming of 3°C by 2100.

Researchers from Finland, Norway, Russia and the US report in the journal Nature Communications that they mapped, on a scale of a kilometre, the buildings, installations, roads and other infrastructure of the permafrost world: a region defined as that where the ground is frozen solid, summer and winter, for at least two consecutive years.

More than 4 million people live in this pan-Arctic landscape: at least 3.6 million of them, and 70% of their transportation and industrial infrastructure, are at risk.

Present reality

“These observations have led me to believe that global warming is not a ‘fake’ but the reality. And here, in Alaska, we are dealing already and will be dealing even more in the near future with this reality,” said Vladimir Romanovsky, of the University of Alaska’s geophysical institute, one of the authors.

Climate scientists and glaciologists have been warning about the rate of change in the Arctic for two decades: one estimate proposed that for every 1°C of warming, around 4 million square kilometres of permafrost − an area bigger than India − could thaw.

Locked in the frozen soil is an estimated 1,700 billion tonnes of carbon: this is about twice the mass of carbon in the atmosphere in the form of the greenhouse gas carbon dioxide. Its release could precipitate even more calamitous climate change. And the economic consequences – assessed at a potential cost of $43 trillion − could be ruinous.

The latest study found that climate change respected no borders: one third of all Arctic infrastructure and 45% of hydrocarbon extraction fields in the Russian Arctic were in high hazard regions: that is, once the soil thawed, the ground became unstable.

Around 470 kms of the Qinghai-Tibet Railway and 280 kms of the Obskaya-Bovanenkovo Railway, the most northerly in the world, lie across what could be thawing permafrost. The scientists identified more than 1,200 settlements in zones where the permafrost could thaw: around 40 of these had populations of 5,000 or more.

“These observations have led me to believe that global warming is not a ‘fake’ but the reality”

Pipelines, too, were endangered: 1,590 kms of the Eastern Siberia-Pacific Ocean oil pipeline, 1,260 kms of the gas pipelines in the Yamal-Nenets region − which supplies one-third of European Union imports − and 550 kms of the Trans-Alaska pipeline systems could be at “considerable risk”: that is, they were in areas where near-surface permafrost could thaw by 2050.

By then around one million people, 36,000 buildings, 13,000 kms of roads and 100 airports could have become high hazard environments. And with them, permafrost thaw could threaten to affect 45% of oil and gas fields in the Russian Arctic.

All forecasts arrive with considerable uncertainties, and the authors concede that they could be wrong. But, they warn, even if they are, their estimates of the infrastructure at risk would probably not be much smaller and could be substantially higher. Around 19 large settlements are in their highest hazard zone “but the number could be as large as 34,” they warn.

If nations acted on the Paris promises, they say, the levels of risk would start to stabilise after 2050. “In contrast, higher greenhouse gas levels would probably result in continued detrimental climate change impacts on the built environment and economic activity in the Arctic.” − Climate News Network

Permafrost thaw and retreating Arctic ice don’t just imperil caribou and bears. People, too, may find the ground shifts beneath their feet.

LONDON, 1 January, 2019 − In just one human generation, citizens of the far north could find themselves on shifting soils as the region’s permafrost thaws. Roads will slump. Buildings will buckle. Pipelines will become at risk of fracture. And in 2050, around three fourths of the people of the permafrost could watch their infrastructure collapse, as what was once hard frozen ground turns into mud.

All this could happen even if the world keeps the promise it made in Paris in 2015 and limits global average warming to just 1.5°C above the level for most of pre-industrial history.

In the last century, the world has already warmed by 1°C on average: the Arctic region has warmed at a far faster rate. At present rates of warming, driven by the profligate use of fossil fuels that raise the levels of greenhouse gases in the atmosphere, the world is on course for an average warming of 3°C by 2100.

Researchers from Finland, Norway, Russia and the US report in the journal Nature Communications that they mapped, on a scale of a kilometre, the buildings, installations, roads and other infrastructure of the permafrost world: a region defined as that where the ground is frozen solid, summer and winter, for at least two consecutive years.

More than 4 million people live in this pan-Arctic landscape: at least 3.6 million of them, and 70% of their transportation and industrial infrastructure, are at risk.

Present reality

“These observations have led me to believe that global warming is not a ‘fake’ but the reality. And here, in Alaska, we are dealing already and will be dealing even more in the near future with this reality,” said Vladimir Romanovsky, of the University of Alaska’s geophysical institute, one of the authors.

Climate scientists and glaciologists have been warning about the rate of change in the Arctic for two decades: one estimate proposed that for every 1°C of warming, around 4 million square kilometres of permafrost − an area bigger than India − could thaw.

Locked in the frozen soil is an estimated 1,700 billion tonnes of carbon: this is about twice the mass of carbon in the atmosphere in the form of the greenhouse gas carbon dioxide. Its release could precipitate even more calamitous climate change. And the economic consequences – assessed at a potential cost of $43 trillion − could be ruinous.

The latest study found that climate change respected no borders: one third of all Arctic infrastructure and 45% of hydrocarbon extraction fields in the Russian Arctic were in high hazard regions: that is, once the soil thawed, the ground became unstable.

Around 470 kms of the Qinghai-Tibet Railway and 280 kms of the Obskaya-Bovanenkovo Railway, the most northerly in the world, lie across what could be thawing permafrost. The scientists identified more than 1,200 settlements in zones where the permafrost could thaw: around 40 of these had populations of 5,000 or more.

“These observations have led me to believe that global warming is not a ‘fake’ but the reality”

Pipelines, too, were endangered: 1,590 kms of the Eastern Siberia-Pacific Ocean oil pipeline, 1,260 kms of the gas pipelines in the Yamal-Nenets region − which supplies one-third of European Union imports − and 550 kms of the Trans-Alaska pipeline systems could be at “considerable risk”: that is, they were in areas where near-surface permafrost could thaw by 2050.

By then around one million people, 36,000 buildings, 13,000 kms of roads and 100 airports could have become high hazard environments. And with them, permafrost thaw could threaten to affect 45% of oil and gas fields in the Russian Arctic.

All forecasts arrive with considerable uncertainties, and the authors concede that they could be wrong. But, they warn, even if they are, their estimates of the infrastructure at risk would probably not be much smaller and could be substantially higher. Around 19 large settlements are in their highest hazard zone “but the number could be as large as 34,” they warn.

If nations acted on the Paris promises, they say, the levels of risk would start to stabilise after 2050. “In contrast, higher greenhouse gas levels would probably result in continued detrimental climate change impacts on the built environment and economic activity in the Arctic.” − Climate News Network

London’s melting ice shows world’s plight

How do you raise awareness of climate change? A novel approach in the UK this winter, shipped in from Greenland, is London’s melting ice.

LONDON, 18 December, 2018 – They stand on the bank of the river Thames, outside the world-famous Tate Modern art venue – London’s melting ice, 24 large blocks, some transparent, some opaque, all different shapes, all gently melting in the not so cold air. Another six stands of ice sit in a square in the heart of London’s financial district.

Ice Watch is the idea of Danish-Icelandic artist Olafur Eliasson and Minik Rosing, a Greenland geologist.

“These blocks tell their own story and I suggest you listen to what they have to say”, Eliasson tells London’s Evening Standard newspaper. “Their melting into the ocean is our world melting.”

The blocks on display in London – weighing a total of more than 100 tonnes – were collected from the cold waters of Nuup Kangerlua fjord near Nuuk, Greenland’s capital.

They had originally been part of Greenland’s ice sheet, which covers about 80% of the island and is the largest ice mass in the northern hemisphere. The blocks were transported to London in containers usually used for exports of frozen fish.

“You can’t live in a perennial state of shock. This is what Ice Watch is about”

Glaciologists say rising air and sea temperatures have caused the pace of melting of the ice sheet to go into overdrive in recent times. There are fears that if the sheet continues to melt at its present rate global sea levels could rise by several metres, flooding coastal cities and large tracts of land.

Visitors can touch the mini-icebergs in London and put their ears to the cold surfaces to listen to the crackling noises as the ice melts, with minuscule air pockets trapped within the blocks cracking open.

Dirt and other material trapped within the ice are evidence of life and changes in the atmosphere stretching back over thousands of years. “Smell, look – and witness the ecological changes our world is undergoing”, says Eliasson.

The artist says that while the facts about climate change and how great a threat it is to the world’s future are clear, people still need to be encouraged to take action.

“We need to communicate the facts of climate change to hearts as well as heads, to emotions as well as minds”, says Eliasson.

Fear is ineffective

“When it comes to people’s choices for or against taking climate action, we are inclined to stick to what we have, here and now, rather than make changes. Inducing fear does not seem an effective strategy.

“You can’t live in a perennial state of shock. This is what Ice Watch is about. I am hopeful that we can push for change. To do so, we have to make use of all the tools at hand, including art.”

Minik Rosing, who has undertaken extensive geological work on the Greenland ice sheet, says the melting of the area’s ice has raised global sea levels by 2.5 millimetres. “Earth is changing at an ever-increasing speed”, he says.

A similar Ice Watch installation has already been staged in Paris. Eliasson has long been involved in climate-related issues. Fifteen years ago his Weather Project exhibition was displayed at Tate Modern.

Ice Watch will be in place in London till December 20 – or until the ice melts completely. – Climate News Network

How do you raise awareness of climate change? A novel approach in the UK this winter, shipped in from Greenland, is London’s melting ice.

LONDON, 18 December, 2018 – They stand on the bank of the river Thames, outside the world-famous Tate Modern art venue – London’s melting ice, 24 large blocks, some transparent, some opaque, all different shapes, all gently melting in the not so cold air. Another six stands of ice sit in a square in the heart of London’s financial district.

Ice Watch is the idea of Danish-Icelandic artist Olafur Eliasson and Minik Rosing, a Greenland geologist.

“These blocks tell their own story and I suggest you listen to what they have to say”, Eliasson tells London’s Evening Standard newspaper. “Their melting into the ocean is our world melting.”

The blocks on display in London – weighing a total of more than 100 tonnes – were collected from the cold waters of Nuup Kangerlua fjord near Nuuk, Greenland’s capital.

They had originally been part of Greenland’s ice sheet, which covers about 80% of the island and is the largest ice mass in the northern hemisphere. The blocks were transported to London in containers usually used for exports of frozen fish.

“You can’t live in a perennial state of shock. This is what Ice Watch is about”

Glaciologists say rising air and sea temperatures have caused the pace of melting of the ice sheet to go into overdrive in recent times. There are fears that if the sheet continues to melt at its present rate global sea levels could rise by several metres, flooding coastal cities and large tracts of land.

Visitors can touch the mini-icebergs in London and put their ears to the cold surfaces to listen to the crackling noises as the ice melts, with minuscule air pockets trapped within the blocks cracking open.

Dirt and other material trapped within the ice are evidence of life and changes in the atmosphere stretching back over thousands of years. “Smell, look – and witness the ecological changes our world is undergoing”, says Eliasson.

The artist says that while the facts about climate change and how great a threat it is to the world’s future are clear, people still need to be encouraged to take action.

“We need to communicate the facts of climate change to hearts as well as heads, to emotions as well as minds”, says Eliasson.

Fear is ineffective

“When it comes to people’s choices for or against taking climate action, we are inclined to stick to what we have, here and now, rather than make changes. Inducing fear does not seem an effective strategy.

“You can’t live in a perennial state of shock. This is what Ice Watch is about. I am hopeful that we can push for change. To do so, we have to make use of all the tools at hand, including art.”

Minik Rosing, who has undertaken extensive geological work on the Greenland ice sheet, says the melting of the area’s ice has raised global sea levels by 2.5 millimetres. “Earth is changing at an ever-increasing speed”, he says.

A similar Ice Watch installation has already been staged in Paris. Eliasson has long been involved in climate-related issues. Fifteen years ago his Weather Project exhibition was displayed at Tate Modern.

Ice Watch will be in place in London till December 20 – or until the ice melts completely. – Climate News Network

Greenland’s icecap melt picks up speed

Recent melting of Greenland’s icecap has been more intense than ever. And all the signs are that it could get worse.

LONDON, 13 December, 2018 – Greenland’s icecap – the largest single store of frozen freshwater in the northern hemisphere – is melting faster than ever, according to two separate studies using two different approaches.

Surface meltwater started flowing over the surface and percolating through the ice at a greater rate in the mid-19th century and accelerated dramatically during the 20th and the first decades of the 21st century, according to a new study of ice cores taken more than 2,000 metres above sea level.

And a 25-year record of European Space Agency satellite data confirms the alarming picture: the elevation of the Greenland ice sheet was changing in the mid-1990s, and the pace of thinning stepped up after 2003. Greenland’s bedrock carries enough ice to raise global sea levels by around seven metres.

“Melting of the Greenland Ice Sheet has gone into overdrive. As a result, Greenland melt is adding to sea level more than at any time in the last three and a half centuries, if not thousands of years,” said Luke Trusel, a glaciologist at Rowan University in the US.

“And increasing melt began around the same time as we started altering the atmosphere in the mid 1800s.”

“The melting and sea level rise we’ve observed will already be dwarfed by what may be expected in the future”

His co-author Sarah Das of the Woods Hole Oceanographic Institution said: “From a historical perspective, today’s melt rates are off the charts, and this study provides the evidence.”

Snow falls on the great icecaps of the two hemispheres, freezes, melts a little in the summer and freezes again, so that – like the rings of a tree – the accumulated precipitation tells a story of successive years of climate change. The two researchers and their colleagues report in Nature that ice cores taken from the icecap between 2003 and 2015 contained enough information for them to assess annual melting rates over several centuries.

They found a clear pattern of more intense melting nearer the present, and over the last 20 years the intensity increased by between 250% and 575%, compared to the 18th century. In the last century the entire planet has warmed by around 1°C as greenhouse gas levels in the atmosphere have risen, in response to ever greater use of fossil fuels.

The message for the future is ominous. “Rather than increasing steadily as climate warms, Greenland will melt increasingly more and more for every degree of warming,” said Dr Trusel. “The melting and sea level rise we’ve observed will already be dwarfed by what may be expected in the future as climate continues to warm.”

Greenland has served for decades as a climate laboratory: change almost imperceptible in lower latitudes can be measured almost on a yearly basis in the high fastnesses of the island, and the Nature study is only the latest twist in a story that is already alarming.

Dangers identified

Scientists long ago took the measure of change on the ice cap, in the glaciers and at the boundary with the Atlantic, and identified the dangers of accelerated warming in the Arctic.

They monitored unexpected increases in the flow of the island’s biggest glaciers, monitored the way the island’s bedrock rose in response to an increased loss of ice, and even identified those reaches of ice that had passed the point of no return.

The Nature scientists backed up their on-the-ground observations with measurements made by satellites. And in an entirely separate study, European researchers report in the journal Earth and Planetary Science Letters that, according to their readings too, the elevation of the icecap had begun to change in ways that enabled them to measure ice loss with the decades, and a recent speed-up.

“A pattern of thinning appears to dominate a large fraction of the ice sheet margins at the beginning of the millennium, with individual outlet glaciers exhibiting large thinning rates,” said Louise Sandberg Sørenson, of the Danish National Space Institute, who led the research.

“Over the full 25-year period, the general picture shows much larger volume losses are experienced in west, northwest and southeast basins of Greenland, compared to the more steady-state situations in the colder north.” – Climate News Network

Recent melting of Greenland’s icecap has been more intense than ever. And all the signs are that it could get worse.

LONDON, 13 December, 2018 – Greenland’s icecap – the largest single store of frozen freshwater in the northern hemisphere – is melting faster than ever, according to two separate studies using two different approaches.

Surface meltwater started flowing over the surface and percolating through the ice at a greater rate in the mid-19th century and accelerated dramatically during the 20th and the first decades of the 21st century, according to a new study of ice cores taken more than 2,000 metres above sea level.

And a 25-year record of European Space Agency satellite data confirms the alarming picture: the elevation of the Greenland ice sheet was changing in the mid-1990s, and the pace of thinning stepped up after 2003. Greenland’s bedrock carries enough ice to raise global sea levels by around seven metres.

“Melting of the Greenland Ice Sheet has gone into overdrive. As a result, Greenland melt is adding to sea level more than at any time in the last three and a half centuries, if not thousands of years,” said Luke Trusel, a glaciologist at Rowan University in the US.

“And increasing melt began around the same time as we started altering the atmosphere in the mid 1800s.”

“The melting and sea level rise we’ve observed will already be dwarfed by what may be expected in the future”

His co-author Sarah Das of the Woods Hole Oceanographic Institution said: “From a historical perspective, today’s melt rates are off the charts, and this study provides the evidence.”

Snow falls on the great icecaps of the two hemispheres, freezes, melts a little in the summer and freezes again, so that – like the rings of a tree – the accumulated precipitation tells a story of successive years of climate change. The two researchers and their colleagues report in Nature that ice cores taken from the icecap between 2003 and 2015 contained enough information for them to assess annual melting rates over several centuries.

They found a clear pattern of more intense melting nearer the present, and over the last 20 years the intensity increased by between 250% and 575%, compared to the 18th century. In the last century the entire planet has warmed by around 1°C as greenhouse gas levels in the atmosphere have risen, in response to ever greater use of fossil fuels.

The message for the future is ominous. “Rather than increasing steadily as climate warms, Greenland will melt increasingly more and more for every degree of warming,” said Dr Trusel. “The melting and sea level rise we’ve observed will already be dwarfed by what may be expected in the future as climate continues to warm.”

Greenland has served for decades as a climate laboratory: change almost imperceptible in lower latitudes can be measured almost on a yearly basis in the high fastnesses of the island, and the Nature study is only the latest twist in a story that is already alarming.

Dangers identified

Scientists long ago took the measure of change on the ice cap, in the glaciers and at the boundary with the Atlantic, and identified the dangers of accelerated warming in the Arctic.

They monitored unexpected increases in the flow of the island’s biggest glaciers, monitored the way the island’s bedrock rose in response to an increased loss of ice, and even identified those reaches of ice that had passed the point of no return.

The Nature scientists backed up their on-the-ground observations with measurements made by satellites. And in an entirely separate study, European researchers report in the journal Earth and Planetary Science Letters that, according to their readings too, the elevation of the icecap had begun to change in ways that enabled them to measure ice loss with the decades, and a recent speed-up.

“A pattern of thinning appears to dominate a large fraction of the ice sheet margins at the beginning of the millennium, with individual outlet glaciers exhibiting large thinning rates,” said Louise Sandberg Sørenson, of the Danish National Space Institute, who led the research.

“Over the full 25-year period, the general picture shows much larger volume losses are experienced in west, northwest and southeast basins of Greenland, compared to the more steady-state situations in the colder north.” – 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

Arctic thaw imperils climate goals

Promises to slow climate change have yet to be implemented. And even if they are, they may not be enough, because of the Arctic thaw.

LONDON, 26 September, 2018 – Austrian researchers have bad news for those nations alarmed about climate change: the Arctic thaw means the chances that the world will exceed the global warming limit set by international agreement are high – and getting ever higher with every tiny shift in the planetary thermometer.

Warming in the Arctic is the fastest on the planet – and any warming will release ever more methane and other forms of stored carbon from the thawing permafrost.

Methane is a greenhouse gas far more potent than carbon dioxide. And as it seeps into the atmosphere, the chances that the world will overshoot its promise to contain planetary warming to “well below” 2°C increase.

This target was agreed by 195 nations at a summit in Paris in 2015. The promise implicit in this historic decision was that the world would by 2100 be no hotter than 1.5°C above historic levels.

Global average temperatures have already risen by about 1°C in the last century, thanks to unconstrained combustion of fossil fuels that deposit ancient stored carbon back into the atmosphere in the form of ever more carbon dioxide.

“Getting back to lower levels after an overshoot will be extremely difficult … we may never get back to safer levels of warming”

But, says an international team led by Thomas Gasser of the International Institute for Applied Systems Analysis in Austria, there are prodigious amounts of carbon stored in the world’s once permanently frozen soils. As these are released, the chances are that global warming will accelerate.

“Permafrost carbon release from previously frozen organic matter is caused by global warming, and will certainly diminish the budget of CO2 we can emit while staying below a certain level of global warming,” Dr Gasser said.

“It is also an irreversible process over the course of a few centuries, and may therefore be considered a ‘tipping’ element of the Earth’s carbon-climate system that puts the linear approximation of the emission budget framework to the test.”

The message behind the formal language of a paper in the journal Nature Geoscience is simple: the world has less time to act than the presidents and prime ministers who signed the Paris Declaration may think.

But this is no surprise. Right from the start, leading climate scientists were warning that the planet could already be much nearer its optimum target than anybody suspected.

Other researchers have repeatedly stressed the need for urgency, and the inadequacy of any of the prepared responses.

Feedback concern

Concern about the permafrost, too, is not new: polar researchers have been arguing for years that any thaw will increase the atmospheric carbon burden, which will in turn accelerate further warning, with potentially catastrophic consequences.

It is one thing to slow the rate of global warming by drastically reducing fossil fuel emissions and restoring the world’s forests so as to arrive at a limit; quite another thing to overshoot the limit and then try to reduce the planetary temperature, the latest study suggests. There is no simple correlation between burning coal or oil and the planetary temperatures that follow.

“Overshooting is a risky strategy and getting back to lower levels after an overshoot will be extremely difficult. However, since we are officially on an overshooting trajectory, we have to prepare ourselves for the possibility that we may never get back to safer levels of warming,” Dr Gasser said.

“Policymakers should understand that there is no elementary proportionality between cumulative CO2 emissions due to human activity and global temperature, as previously believed, and that overshooting may have serious consequences.” – Climate News Network


 

Promises to slow climate change have yet to be implemented. And even if they are, they may not be enough, because of the Arctic thaw.

LONDON, 26 September, 2018 – Austrian researchers have bad news for those nations alarmed about climate change: the Arctic thaw means the chances that the world will exceed the global warming limit set by international agreement are high – and getting ever higher with every tiny shift in the planetary thermometer.

Warming in the Arctic is the fastest on the planet – and any warming will release ever more methane and other forms of stored carbon from the thawing permafrost.

Methane is a greenhouse gas far more potent than carbon dioxide. And as it seeps into the atmosphere, the chances that the world will overshoot its promise to contain planetary warming to “well below” 2°C increase.

This target was agreed by 195 nations at a summit in Paris in 2015. The promise implicit in this historic decision was that the world would by 2100 be no hotter than 1.5°C above historic levels.

Global average temperatures have already risen by about 1°C in the last century, thanks to unconstrained combustion of fossil fuels that deposit ancient stored carbon back into the atmosphere in the form of ever more carbon dioxide.

“Getting back to lower levels after an overshoot will be extremely difficult … we may never get back to safer levels of warming”

But, says an international team led by Thomas Gasser of the International Institute for Applied Systems Analysis in Austria, there are prodigious amounts of carbon stored in the world’s once permanently frozen soils. As these are released, the chances are that global warming will accelerate.

“Permafrost carbon release from previously frozen organic matter is caused by global warming, and will certainly diminish the budget of CO2 we can emit while staying below a certain level of global warming,” Dr Gasser said.

“It is also an irreversible process over the course of a few centuries, and may therefore be considered a ‘tipping’ element of the Earth’s carbon-climate system that puts the linear approximation of the emission budget framework to the test.”

The message behind the formal language of a paper in the journal Nature Geoscience is simple: the world has less time to act than the presidents and prime ministers who signed the Paris Declaration may think.

But this is no surprise. Right from the start, leading climate scientists were warning that the planet could already be much nearer its optimum target than anybody suspected.

Other researchers have repeatedly stressed the need for urgency, and the inadequacy of any of the prepared responses.

Feedback concern

Concern about the permafrost, too, is not new: polar researchers have been arguing for years that any thaw will increase the atmospheric carbon burden, which will in turn accelerate further warning, with potentially catastrophic consequences.

It is one thing to slow the rate of global warming by drastically reducing fossil fuel emissions and restoring the world’s forests so as to arrive at a limit; quite another thing to overshoot the limit and then try to reduce the planetary temperature, the latest study suggests. There is no simple correlation between burning coal or oil and the planetary temperatures that follow.

“Overshooting is a risky strategy and getting back to lower levels after an overshoot will be extremely difficult. However, since we are officially on an overshooting trajectory, we have to prepare ourselves for the possibility that we may never get back to safer levels of warming,” Dr Gasser said.

“Policymakers should understand that there is no elementary proportionality between cumulative CO2 emissions due to human activity and global temperature, as previously believed, and that overshooting may have serious consequences.” – Climate News Network


 

‘Eternal’ Swiss snow is melting faster

Scientists say stretches of “eternal” Swiss snow are melting faster than 20 years ago, with serious impacts for water supply and tourism.

LONDON, 21 September, 2018 – Parts of Europe’s alpine mountain chain are undergoing accelerating melting, as the “eternal” Swiss snow thaws ever faster, threatening both the skiing industry and the nation’s water supply.

Over a period of only 22 years, thousands of satellite images have provided irrefutable evidence that an extra 5,200 square kilometres of the country are now snow-free, compared with the decade 1995-2005.

Researchers from the University of Geneva and the United Nations Environment Programme have used data from four satellites which have been constantly photographing the Earth from space, compiling a record published by the Swiss Data Cube, which uses Earth observations to give a comprehensive  picture of the country’s snow cover and much else besides, including crops grown and forest cover.

It is the loss of snow cover that most disturbs the scientists. What they call “the eternal snow zone” still covered 27% of Swiss territory in the years from 1995 to 2005. Ten years later it had fallen to 23% – a loss of 2,100 sq km.

The eternal snow line marks the part of Switzerland above which the snow never used to melt in summer or winter. It is also defined as the area where any precipitation year-round has an 80-100% chance of being snow.

“We have stored the equivalent of 6,500 images covering 34 years, a feat that only an open data policy has made possible”

Other parts of the country, including the Swiss Plateau (about 30% of Switzerland’s area), the Rhone Valley, the Alps and the Jura mountains are also losing snow cover, adding up to the 5,200 sq km total. These areas, below the eternal snow line, have until now usually had lying snow in the winter.

The study was launched in 2016 on behalf of Switzerland’s Federal Office for the Environment. Knowing the extent of snow cover and its retreat is essential for developing public policies, the researchers say.

Beyond the economic issues linked to the threat to ski resorts – a familiar area of concern, heightened by this latest research, as many of them now face shortened seasons or outright abandonment – other problems such as flood risk and water supply are coming to the fore. Snow stores water in the winter for release in spring and summer, for both agriculture and drinking water.

Currently the increasing loss of ice from glaciers in the summer is making up for the missing snow, but previous work by scientists has shown that in the future, when glaciers disappear altogether, Switzerland could face a crisis.

The researchers have relied on the information available from the Data Cube to establish what is happening on the peaks. By superimposing repeated pictures of the same place over one another they have been able to observe small changes over time.

Wealth of data

The data was made freely available to researchers. One of them, Grégory Giuliani, said: “We have stored the equivalent of 6,500 images covering 34 years, a feat that only an open data policy has made possible. If we had had to acquire these images at market value, more than 6 million Swiss francs would have been invested.

“Knowing that each pixel of each image corresponds to the observation of a square of 10 by 10 meters, we have 110 billion observations today. It is inestimable wealth for the scientific community.”

Apart from snow cover scientists are worried about many other changes taking place in Switzerland because of climate change. They already know that glaciers are melting at record speeds and plants, birds and insects are heading further up the mountains, but there is much else to be gleaned from the new data base.

The Data Cube offers the possibility of studying vegetation, the evolution and rotation of agricultural areas, urbanisation and even water quality, as satellite images can be used to monitor three essential indicators in lakes and rivers: suspended particles, whether organic or mineral; chlorophyll content; and surface temperature.

The data are freely accessible, not only to scientists worldwide but also to the public, making it easy to compare data for specific areas of the territory at different times. “Our ambition is that everyone should be able to navigate freely in Swiss territory to understand its evolution”, said Grégory Giuliani. – Climate News Network

Scientists say stretches of “eternal” Swiss snow are melting faster than 20 years ago, with serious impacts for water supply and tourism.

LONDON, 21 September, 2018 – Parts of Europe’s alpine mountain chain are undergoing accelerating melting, as the “eternal” Swiss snow thaws ever faster, threatening both the skiing industry and the nation’s water supply.

Over a period of only 22 years, thousands of satellite images have provided irrefutable evidence that an extra 5,200 square kilometres of the country are now snow-free, compared with the decade 1995-2005.

Researchers from the University of Geneva and the United Nations Environment Programme have used data from four satellites which have been constantly photographing the Earth from space, compiling a record published by the Swiss Data Cube, which uses Earth observations to give a comprehensive  picture of the country’s snow cover and much else besides, including crops grown and forest cover.

It is the loss of snow cover that most disturbs the scientists. What they call “the eternal snow zone” still covered 27% of Swiss territory in the years from 1995 to 2005. Ten years later it had fallen to 23% – a loss of 2,100 sq km.

The eternal snow line marks the part of Switzerland above which the snow never used to melt in summer or winter. It is also defined as the area where any precipitation year-round has an 80-100% chance of being snow.

“We have stored the equivalent of 6,500 images covering 34 years, a feat that only an open data policy has made possible”

Other parts of the country, including the Swiss Plateau (about 30% of Switzerland’s area), the Rhone Valley, the Alps and the Jura mountains are also losing snow cover, adding up to the 5,200 sq km total. These areas, below the eternal snow line, have until now usually had lying snow in the winter.

The study was launched in 2016 on behalf of Switzerland’s Federal Office for the Environment. Knowing the extent of snow cover and its retreat is essential for developing public policies, the researchers say.

Beyond the economic issues linked to the threat to ski resorts – a familiar area of concern, heightened by this latest research, as many of them now face shortened seasons or outright abandonment – other problems such as flood risk and water supply are coming to the fore. Snow stores water in the winter for release in spring and summer, for both agriculture and drinking water.

Currently the increasing loss of ice from glaciers in the summer is making up for the missing snow, but previous work by scientists has shown that in the future, when glaciers disappear altogether, Switzerland could face a crisis.

The researchers have relied on the information available from the Data Cube to establish what is happening on the peaks. By superimposing repeated pictures of the same place over one another they have been able to observe small changes over time.

Wealth of data

The data was made freely available to researchers. One of them, Grégory Giuliani, said: “We have stored the equivalent of 6,500 images covering 34 years, a feat that only an open data policy has made possible. If we had had to acquire these images at market value, more than 6 million Swiss francs would have been invested.

“Knowing that each pixel of each image corresponds to the observation of a square of 10 by 10 meters, we have 110 billion observations today. It is inestimable wealth for the scientific community.”

Apart from snow cover scientists are worried about many other changes taking place in Switzerland because of climate change. They already know that glaciers are melting at record speeds and plants, birds and insects are heading further up the mountains, but there is much else to be gleaned from the new data base.

The Data Cube offers the possibility of studying vegetation, the evolution and rotation of agricultural areas, urbanisation and even water quality, as satellite images can be used to monitor three essential indicators in lakes and rivers: suspended particles, whether organic or mineral; chlorophyll content; and surface temperature.

The data are freely accessible, not only to scientists worldwide but also to the public, making it easy to compare data for specific areas of the territory at different times. “Our ambition is that everyone should be able to navigate freely in Swiss territory to understand its evolution”, said Grégory Giuliani. – Climate News Network