Category Archives: Polar

Record Antarctic temperatures fuel sea level worry


Sea levels may threaten coastal cities sooner than expected, scientists say, as ice loss speeds up and Antarctic temperatures rise.

LONDON, 20 February, 2020 − Across the world, people now alive in coastal areas may face dangerously rising seas within their lifetimes, as record Antarctic temperatures and rapid melting of the continent’s ice drive global sea levels upwards.

Temperatures on the Antarctic Peninsula reached more than 20°C for the first time in history earlier this month, the Guardian reported: “The 20.75C logged by Brazilian scientists at Seymour Island on 9 February was almost a full degree higher than the previous record of 19.8C, taken on Signy Island in January 1982.”

The Antarctic Peninsula has warmed by almost 3°C since the start of the Industrial Revolution around 200 years ago − faster than almost anywhere else on Earth. But scientists are increasingly concerned not only about the Peninsula, but with the possibility that the entire southern continent may be heating up much faster than current estimates suggest.

Among evidence of increasing scientific effort to determine what is happening is a joint UK-US collaboration, due to report in 2023 on the chances of the collapse of the huge Thwaites glacier in West Antarctica, where from 1992 to 2017 the annual rate of ice loss rose threefold.

Big speed-up

Now a study by scientists co-ordinated by Germany’s Potsdam Institute for Climate Impact Research (PIK) says sea level rise caused by Antarctica’s ice loss could become a major risk for coastal protection in the near future.

After what they call “an exceptionally comprehensive comparison of state-of-the-art computer models from around the world”, they conclude that Antarctica alone could cause global sea level to rise by 2100 by up to three times more than it did in the last century.

“The ‘Antarctica Factor’ turns out to be the greatest risk, and also the greatest uncertainty, for sea levels around the globe,” says the lead author, Anders Levermann of PIK and Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York.

“While we saw about 19 centimetres of sea level rise in the past 100 years, Antarctic ice loss could lead to up to 58 centimetres within this century”, he said.

“We know for certain that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai”

“Coastal planning cannot merely rely on the best guess. It requires a risk analysis. Our study provides exactly that. The sea level contribution of Antarctica is very likely not going to be more than 58 centimetres.”

Thermal expansion of the oceans by global warming and the melting of glaciers, which so far have been the most important factors in sea level rise, will add to the contribution from Antarctic ice loss, making the overall sea level rise risk even bigger. But the ‘Antarctica Factor’ is about to become the most important element, according to the study, published in the journal Earth System Dynamics.

The range of sea-level rise estimates the scientists have come up with is fairly large. Assuming that humanity keeps on emitting greenhouse gases as before, they say, the range they call “very likely” to describe the future is between 6 and 58 cms for this century.

If greenhouse gas emissions were reduced rapidly, it would be between 4 and 37 cms. Importantly, the difference between a business-as-usual scenario and one of emissions reductions becomes substantially greater as time passes.

More robust insights

Sixteen ice sheet modelling groups consisting of 36 researchers from 27 institutes contributed to the new study. A similar study six years ago had to rely on the output of only five ice sheet models.

“The more computer simulation models we use, all of them with slightly different dynamic representations of the Antarctic ice sheet, the wider the range of results that we yield − but also the more robust the insights that we gain”, said co-author Sophie Nowicki of the NASA Goddard Space Flight Center.

“There are still large uncertainties, but we are constantly improving our understanding of the largest ice sheet on Earth. Comparing model outputs is a forceful tool to provide society with the necessary information for rational decisions.”

Over the long term, the Antarctic ice sheet has the potential ultimately to raise sea levels by many tens of metres. “What we know for certain”, said Professor Levermann, “is that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai.” − Climate News Network


Sea levels may threaten coastal cities sooner than expected, scientists say, as ice loss speeds up and Antarctic temperatures rise.

LONDON, 20 February, 2020 − Across the world, people now alive in coastal areas may face dangerously rising seas within their lifetimes, as record Antarctic temperatures and rapid melting of the continent’s ice drive global sea levels upwards.

Temperatures on the Antarctic Peninsula reached more than 20°C for the first time in history earlier this month, the Guardian reported: “The 20.75C logged by Brazilian scientists at Seymour Island on 9 February was almost a full degree higher than the previous record of 19.8C, taken on Signy Island in January 1982.”

The Antarctic Peninsula has warmed by almost 3°C since the start of the Industrial Revolution around 200 years ago − faster than almost anywhere else on Earth. But scientists are increasingly concerned not only about the Peninsula, but with the possibility that the entire southern continent may be heating up much faster than current estimates suggest.

Among evidence of increasing scientific effort to determine what is happening is a joint UK-US collaboration, due to report in 2023 on the chances of the collapse of the huge Thwaites glacier in West Antarctica, where from 1992 to 2017 the annual rate of ice loss rose threefold.

Big speed-up

Now a study by scientists co-ordinated by Germany’s Potsdam Institute for Climate Impact Research (PIK) says sea level rise caused by Antarctica’s ice loss could become a major risk for coastal protection in the near future.

After what they call “an exceptionally comprehensive comparison of state-of-the-art computer models from around the world”, they conclude that Antarctica alone could cause global sea level to rise by 2100 by up to three times more than it did in the last century.

“The ‘Antarctica Factor’ turns out to be the greatest risk, and also the greatest uncertainty, for sea levels around the globe,” says the lead author, Anders Levermann of PIK and Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York.

“While we saw about 19 centimetres of sea level rise in the past 100 years, Antarctic ice loss could lead to up to 58 centimetres within this century”, he said.

“We know for certain that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai”

“Coastal planning cannot merely rely on the best guess. It requires a risk analysis. Our study provides exactly that. The sea level contribution of Antarctica is very likely not going to be more than 58 centimetres.”

Thermal expansion of the oceans by global warming and the melting of glaciers, which so far have been the most important factors in sea level rise, will add to the contribution from Antarctic ice loss, making the overall sea level rise risk even bigger. But the ‘Antarctica Factor’ is about to become the most important element, according to the study, published in the journal Earth System Dynamics.

The range of sea-level rise estimates the scientists have come up with is fairly large. Assuming that humanity keeps on emitting greenhouse gases as before, they say, the range they call “very likely” to describe the future is between 6 and 58 cms for this century.

If greenhouse gas emissions were reduced rapidly, it would be between 4 and 37 cms. Importantly, the difference between a business-as-usual scenario and one of emissions reductions becomes substantially greater as time passes.

More robust insights

Sixteen ice sheet modelling groups consisting of 36 researchers from 27 institutes contributed to the new study. A similar study six years ago had to rely on the output of only five ice sheet models.

“The more computer simulation models we use, all of them with slightly different dynamic representations of the Antarctic ice sheet, the wider the range of results that we yield − but also the more robust the insights that we gain”, said co-author Sophie Nowicki of the NASA Goddard Space Flight Center.

“There are still large uncertainties, but we are constantly improving our understanding of the largest ice sheet on Earth. Comparing model outputs is a forceful tool to provide society with the necessary information for rational decisions.”

Over the long term, the Antarctic ice sheet has the potential ultimately to raise sea levels by many tens of metres. “What we know for certain”, said Professor Levermann, “is that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai.” − Climate News Network

Speeding sea level rise threatens nuclear plants

With sea level rise accelerating faster than thought, the risk is growing for coastal cities − and for nuclear power stations.

LONDON, 14 February, 2020 − The latest science shows how the pace of sea level rise is speeding up, fuelling fears that not only millions of homes will be under threat, but that vulnerable installations like docks and power plants will be overwhelmed by the waves.

New research using satellite data over a 30-year period shows that around the year 2000 sea level rise was 2mm a year, by 2010 it was 3mm and now it is at 4mm, with the pace of change still increasing.

The calculations were made by a research student, Tadea Veng, at the Technical University of Denmark, which has a special interest in Greenland, where the icecap is melting fast. That, combined with accelerating melting in Antarctica and further warming of the oceans, is raising sea levels across the globe.

The report coincides with a European Environment Agency (EEA) study whose maps show large areas of the shorelines of countries with coastlines on the North Sea will go under water unless heavily defended against sea level rise.

Based on the maps, newspapers like The Guardian in London have predicted that more than half of one key UK east coast provincial port − Hull − will be swamped. Ironically, Hull is the base for making giant wind turbine blades for use in the North Sea.

“It’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges”

The argument about how much the sea level will rise this century has been raging in scientific circles since the 1990s. At the start, predictions of sea level rise took into account only two possible causes: the expansion of seawater as it warmed, and the melting of mountain glaciers away from the poles.

In the early Intergovernmental Panel on Climate Change reports back then, the melting of the polar ice caps was not included, because scientists could not agree whether greater snowfall on the top of the ice caps in winter might balance out summer melting. Many of them also thought Antarctica would not melt at all, or not for centuries, because it was too cold.

Both the extra snow theory and the “too cold to melt” idea have now been discounted. In Antarctica this is partly because the sea has warmed up so much that it is melting the glaciers’ ice from beneath – something the scientists had not foreseen.

Alarm about sea level rise elsewhere has been increasing outside the scientific community, partly because many nuclear power plants are on coasts. Even those that are nearing the end of their working lives will be radio-active for another century, and many have highly dangerous spent fuel on site in storage ponds with no disposal route organised.

Perhaps most alarmed are British residents, whose government is currently planning a number of new seaside nuclear stations in low-lying coastal areas. Some will be under water this century according to the EEA, particularly one planned for Sizewell in eastern England.

Hard to tell

The Agency’s report says estimates of sea level rise by 2100 vary, with an upper limit of one metre generally accepted, but up to 2.5 metres predicted by some scientists. The latest research by Danish scientists suggests judiciously that with the speed of sea level rise continuing to accelerate, it is impossible to be sure.

A report by campaigners who oppose building nuclear power stations on Britain’s vulnerable coast expresses extreme alarm, saying both nuclear regulators and the giant French energy company EDF are too complacent about the problem.

The report says: “Polar ice caps appear to be melting faster than expected, and what is particularly worrying is that the rate of melting seems to be increasing. Some researchers say sea levels could rise by as much as six metres or more by 2100, even if the 2°C Paris targethttps://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement is met.

“But it’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges. An increase in sea level of 50cm would mean the storm that used to come every thousand years will now come every 100 years. If you increase that to a metre, then that millennial storm is likely to come once a decade.

“Bearing in mind that there will probably be nuclear waste on the Hinkley Point C site [home to the new twin reactors being built by EDF in the West of England] until at least 2150, the question neither the Office of Nuclear Regulation nor EDF seem to be asking is whether further flood protection measures can be put in place fast enough to deal with unexpected and unpredicted storm surges.” − Climate News Network

With sea level rise accelerating faster than thought, the risk is growing for coastal cities − and for nuclear power stations.

LONDON, 14 February, 2020 − The latest science shows how the pace of sea level rise is speeding up, fuelling fears that not only millions of homes will be under threat, but that vulnerable installations like docks and power plants will be overwhelmed by the waves.

New research using satellite data over a 30-year period shows that around the year 2000 sea level rise was 2mm a year, by 2010 it was 3mm and now it is at 4mm, with the pace of change still increasing.

The calculations were made by a research student, Tadea Veng, at the Technical University of Denmark, which has a special interest in Greenland, where the icecap is melting fast. That, combined with accelerating melting in Antarctica and further warming of the oceans, is raising sea levels across the globe.

The report coincides with a European Environment Agency (EEA) study whose maps show large areas of the shorelines of countries with coastlines on the North Sea will go under water unless heavily defended against sea level rise.

Based on the maps, newspapers like The Guardian in London have predicted that more than half of one key UK east coast provincial port − Hull − will be swamped. Ironically, Hull is the base for making giant wind turbine blades for use in the North Sea.

“It’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges”

The argument about how much the sea level will rise this century has been raging in scientific circles since the 1990s. At the start, predictions of sea level rise took into account only two possible causes: the expansion of seawater as it warmed, and the melting of mountain glaciers away from the poles.

In the early Intergovernmental Panel on Climate Change reports back then, the melting of the polar ice caps was not included, because scientists could not agree whether greater snowfall on the top of the ice caps in winter might balance out summer melting. Many of them also thought Antarctica would not melt at all, or not for centuries, because it was too cold.

Both the extra snow theory and the “too cold to melt” idea have now been discounted. In Antarctica this is partly because the sea has warmed up so much that it is melting the glaciers’ ice from beneath – something the scientists had not foreseen.

Alarm about sea level rise elsewhere has been increasing outside the scientific community, partly because many nuclear power plants are on coasts. Even those that are nearing the end of their working lives will be radio-active for another century, and many have highly dangerous spent fuel on site in storage ponds with no disposal route organised.

Perhaps most alarmed are British residents, whose government is currently planning a number of new seaside nuclear stations in low-lying coastal areas. Some will be under water this century according to the EEA, particularly one planned for Sizewell in eastern England.

Hard to tell

The Agency’s report says estimates of sea level rise by 2100 vary, with an upper limit of one metre generally accepted, but up to 2.5 metres predicted by some scientists. The latest research by Danish scientists suggests judiciously that with the speed of sea level rise continuing to accelerate, it is impossible to be sure.

A report by campaigners who oppose building nuclear power stations on Britain’s vulnerable coast expresses extreme alarm, saying both nuclear regulators and the giant French energy company EDF are too complacent about the problem.

The report says: “Polar ice caps appear to be melting faster than expected, and what is particularly worrying is that the rate of melting seems to be increasing. Some researchers say sea levels could rise by as much as six metres or more by 2100, even if the 2°C Paris targethttps://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement is met.

“But it’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges. An increase in sea level of 50cm would mean the storm that used to come every thousand years will now come every 100 years. If you increase that to a metre, then that millennial storm is likely to come once a decade.

“Bearing in mind that there will probably be nuclear waste on the Hinkley Point C site [home to the new twin reactors being built by EDF in the West of England] until at least 2150, the question neither the Office of Nuclear Regulation nor EDF seem to be asking is whether further flood protection measures can be put in place fast enough to deal with unexpected and unpredicted storm surges.” − Climate News Network

Rewilding the Arctic can slow the climate crisis

It would be a monumental task to start rewilding the Arctic, but the climate payoff could be mammoth.

LONDON, 29 January, 2020 − Releasing herds of large animals onto the tundra − rewilding the Arctic − to create vast grasslands could slow down global heating by storing carbon and preserving the permafrost, UK scientists say.

With no woolly mammoths available nowadays, the scientists, from the University of Oxford, suggest an alternative in the Philosophical Transactions of the Royal Society B − importing large herds of bison and horses to provide the mega-fauna that would prevent tree growth and create huge areas of grazing land.

These big animals, originally present in the Arctic together with the reindeer, wolves and other large creatures still living there, would create a natural geo-engineering project to alter the landscape, the researchers say. The idea is to preserve as much carbon in the soil as possible and reflect more sunlight back into space.

The scientists visited Pleistocene Park, a Russian experiment in north-eastern Siberia, which is an attempt to recreate the mammoth steppe ecosystem of the last ice age by re-introducing large grazing animals.

Trees that are growing ever further north as the Arctic warms are in turn leading to the melting of more permafrost by breaking up the snow which otherwise reflects sunlight away from the Earth. Instead, the snow absorbs more of the sunlight, enhancing the warming further.

“The Arctic is already changing, and fast. Taking a ‘do nothing’ approach now is a decision to allow rapid, irreversible changes to occur”

By removing woody vegetation, enhancing grass growth and trampling on snow in search of winter forage, the scientists say, large mammals increase the amount of incoming solar energy that bounces back to space − the albedo effect.

Unlike shallow-rooted trees, grasslands also favour the capture of carbon in the deep roots of grasses and enable cold winter temperatures to penetrate deeper into the soil. Altogether, they say, these changes would have a net cooling effect on Arctic lands and delay permafrost melt.

“The Arctic is already changing, and fast. Taking a ‘do nothing’ approach now is a decision to allow rapid, irreversible changes to occur”, says lead author Dr Marc Macias-Fauria, at Oxford’s School of Geography and the Environment.

“Although the science of Arctic eco-engineering is largely untested, it has the potential to make a big difference, and action in this region should be given serious consideration.”

Big emissions savings

The study estimates that carbon emissions from thawing permafrost could be around 4.35 billion tonnes a year over this century. This is around half as much as fossil fuel emissions, and three times more than estimates of the emissions produced by current and projected land use change, for example in tropical forests.

One of the drawbacks to the scheme is the need to import large quantities of relatively scarce animals like bison into the vast expanses that would need to be rewilded. It would take time to build up the numbers of animals required.

The fossil record in the period the scientists are trying to recreate shows that each square kilometre contained an average of one mammoth, 5 bison, 7.5 horses, 15 reindeer, 0.25 cave lions, and one wolf. This is around the animal density of present-day African savanna game reserves. Rewilding efforts would initially focus on bison and horses.

The researchers believe the scheme could be economic, especially if the price of the carbon saved is reckoned in. They provide a detailed analysis for an experiment over a period of 10 years for the introduction and monitoring of three large-scale trial areas, which includes importing 1,000 animals for each of the three at a cost of US$114 million (£88m).  On an annual basis this alone would keep 72,000 tonnes of carbon in the ground.

The scientists believe that rewilding could be a cost-effective solution and bring extra benefits like new tourism and “carbon-negative wild meat”, which would cut the demand for farmed beef and reduce pressure on forested areas in the tropics. They also say the study constitutes a potential opportunity for UK-Russia cooperation on climate change mitigation. − Climate News Network

It would be a monumental task to start rewilding the Arctic, but the climate payoff could be mammoth.

LONDON, 29 January, 2020 − Releasing herds of large animals onto the tundra − rewilding the Arctic − to create vast grasslands could slow down global heating by storing carbon and preserving the permafrost, UK scientists say.

With no woolly mammoths available nowadays, the scientists, from the University of Oxford, suggest an alternative in the Philosophical Transactions of the Royal Society B − importing large herds of bison and horses to provide the mega-fauna that would prevent tree growth and create huge areas of grazing land.

These big animals, originally present in the Arctic together with the reindeer, wolves and other large creatures still living there, would create a natural geo-engineering project to alter the landscape, the researchers say. The idea is to preserve as much carbon in the soil as possible and reflect more sunlight back into space.

The scientists visited Pleistocene Park, a Russian experiment in north-eastern Siberia, which is an attempt to recreate the mammoth steppe ecosystem of the last ice age by re-introducing large grazing animals.

Trees that are growing ever further north as the Arctic warms are in turn leading to the melting of more permafrost by breaking up the snow which otherwise reflects sunlight away from the Earth. Instead, the snow absorbs more of the sunlight, enhancing the warming further.

“The Arctic is already changing, and fast. Taking a ‘do nothing’ approach now is a decision to allow rapid, irreversible changes to occur”

By removing woody vegetation, enhancing grass growth and trampling on snow in search of winter forage, the scientists say, large mammals increase the amount of incoming solar energy that bounces back to space − the albedo effect.

Unlike shallow-rooted trees, grasslands also favour the capture of carbon in the deep roots of grasses and enable cold winter temperatures to penetrate deeper into the soil. Altogether, they say, these changes would have a net cooling effect on Arctic lands and delay permafrost melt.

“The Arctic is already changing, and fast. Taking a ‘do nothing’ approach now is a decision to allow rapid, irreversible changes to occur”, says lead author Dr Marc Macias-Fauria, at Oxford’s School of Geography and the Environment.

“Although the science of Arctic eco-engineering is largely untested, it has the potential to make a big difference, and action in this region should be given serious consideration.”

Big emissions savings

The study estimates that carbon emissions from thawing permafrost could be around 4.35 billion tonnes a year over this century. This is around half as much as fossil fuel emissions, and three times more than estimates of the emissions produced by current and projected land use change, for example in tropical forests.

One of the drawbacks to the scheme is the need to import large quantities of relatively scarce animals like bison into the vast expanses that would need to be rewilded. It would take time to build up the numbers of animals required.

The fossil record in the period the scientists are trying to recreate shows that each square kilometre contained an average of one mammoth, 5 bison, 7.5 horses, 15 reindeer, 0.25 cave lions, and one wolf. This is around the animal density of present-day African savanna game reserves. Rewilding efforts would initially focus on bison and horses.

The researchers believe the scheme could be economic, especially if the price of the carbon saved is reckoned in. They provide a detailed analysis for an experiment over a period of 10 years for the introduction and monitoring of three large-scale trial areas, which includes importing 1,000 animals for each of the three at a cost of US$114 million (£88m).  On an annual basis this alone would keep 72,000 tonnes of carbon in the ground.

The scientists believe that rewilding could be a cost-effective solution and bring extra benefits like new tourism and “carbon-negative wild meat”, which would cut the demand for farmed beef and reduce pressure on forested areas in the tropics. They also say the study constitutes a potential opportunity for UK-Russia cooperation on climate change mitigation. − Climate News Network

Ice-free Arctic Ocean allowed ancient carbon leaks

As the world warms, more greenhouse gas will enter the atmosphere. Researchers now think an ice-free Arctic Ocean explains how and why.

LONDON, 10 January, 2020 – Deep in a cave in Siberia, Israeli, Russian and British scientists have identified evidence of periodic losses of carbon from the permafrost. And the unexpected link is not simply with peak periods of bygone global warming, but with an ice-free Arctic Ocean.

The escape into the atmosphere of prodigious volumes of methane and carbon dioxide from the thawing soils is in step not with average planetary temperature rise, but with long periods when the Arctic Ocean is free of ice every summer.

Fact one: about one quarter of land in the northern hemisphere is now, and has been for much of the last half million years, permanently frozen, and with it about twice as much atmospheric carbon – in the form of peat and preserved vegetation – as there exists freely in the planetary atmosphere.

Fact two: in the most recent decades, sea ice has been both thinning and dwindling rapidly, and the polar ocean could by 2050 become almost entirely ice-free in the summer months.

“This discovery about the behaviour of the permafrost suggests that the expected loss of Arctic sea ice will accelerate melting of the permafrost presently found across much of Siberia”

And this twist in the tale of a rapidly-warming Arctic is preserved in stalagmite formations in a cave deep beneath the rim of the Arctic Circle in Siberia.

The chronology of stalagmite and stalactite development can be established precisely by the pattern of uranium and lead isotope deposits in formations, built up imperceptibly by the steady drip of water from, and through, the soils far above.

That is, the speleothems – a geologist’s catch-all word for both stalactite and stalagmite – form fastest when the permafrost has thawed. And unexpectedly, the periods of thaw did not match the peaks of interglacial warming during the last 1.35 million years. They did however coincide with periods when the Arctic was ice-free in the summer.

“This discovery about the behaviour of the permafrost suggests that the expected loss of Arctic sea ice in the future will accelerate melting of the permafrost presently found across much of Siberia,” said Gideon Henderson of the University of Oxford, and one of the authors of a new study in the journal Nature.

Permafrost in jeopardy

The argument goes like this: if there is no sea ice then more heat and moisture is delivered from the ocean to the atmosphere, with warmer air flowing over Siberia, and therefore more autumn snowfall.

A blanket of snow insulates the soil beneath from the extreme winter cold, so ground temperatures go up, to unsettle the permafrost and start a thaw that leads to accelerated plant decay and ever-increasing escape of carbon dioxide and methane that would otherwise have been frozen into the permafrost.

So the stalagmites endure as evidence of these warmer soils and survive as a direct link to periods of ice-free ocean.

“If these processes continue during modern climate change, future loss of summer Arctic sea ice will accelerate the thawing of Siberian permafrost,” the scientists say. – Climate News Network

As the world warms, more greenhouse gas will enter the atmosphere. Researchers now think an ice-free Arctic Ocean explains how and why.

LONDON, 10 January, 2020 – Deep in a cave in Siberia, Israeli, Russian and British scientists have identified evidence of periodic losses of carbon from the permafrost. And the unexpected link is not simply with peak periods of bygone global warming, but with an ice-free Arctic Ocean.

The escape into the atmosphere of prodigious volumes of methane and carbon dioxide from the thawing soils is in step not with average planetary temperature rise, but with long periods when the Arctic Ocean is free of ice every summer.

Fact one: about one quarter of land in the northern hemisphere is now, and has been for much of the last half million years, permanently frozen, and with it about twice as much atmospheric carbon – in the form of peat and preserved vegetation – as there exists freely in the planetary atmosphere.

Fact two: in the most recent decades, sea ice has been both thinning and dwindling rapidly, and the polar ocean could by 2050 become almost entirely ice-free in the summer months.

“This discovery about the behaviour of the permafrost suggests that the expected loss of Arctic sea ice will accelerate melting of the permafrost presently found across much of Siberia”

And this twist in the tale of a rapidly-warming Arctic is preserved in stalagmite formations in a cave deep beneath the rim of the Arctic Circle in Siberia.

The chronology of stalagmite and stalactite development can be established precisely by the pattern of uranium and lead isotope deposits in formations, built up imperceptibly by the steady drip of water from, and through, the soils far above.

That is, the speleothems – a geologist’s catch-all word for both stalactite and stalagmite – form fastest when the permafrost has thawed. And unexpectedly, the periods of thaw did not match the peaks of interglacial warming during the last 1.35 million years. They did however coincide with periods when the Arctic was ice-free in the summer.

“This discovery about the behaviour of the permafrost suggests that the expected loss of Arctic sea ice in the future will accelerate melting of the permafrost presently found across much of Siberia,” said Gideon Henderson of the University of Oxford, and one of the authors of a new study in the journal Nature.

Permafrost in jeopardy

The argument goes like this: if there is no sea ice then more heat and moisture is delivered from the ocean to the atmosphere, with warmer air flowing over Siberia, and therefore more autumn snowfall.

A blanket of snow insulates the soil beneath from the extreme winter cold, so ground temperatures go up, to unsettle the permafrost and start a thaw that leads to accelerated plant decay and ever-increasing escape of carbon dioxide and methane that would otherwise have been frozen into the permafrost.

So the stalagmites endure as evidence of these warmer soils and survive as a direct link to periods of ice-free ocean.

“If these processes continue during modern climate change, future loss of summer Arctic sea ice will accelerate the thawing of Siberian permafrost,” the scientists say. – Climate News Network

Russia moves to exploit Arctic riches

As the polar sea ice vanishes faster, Russia unveils plans to exploit Arctic riches: fossil fuel deposits, minerals and new shipping routes.

LONDON, 7 January, 2020 − The Russian government has published ambitious plans to exploit the Arctic riches off its northern coast, opening up the polar region to exploitation with a fleet of 40 ships, new roads and railways and four enlarged airports.

The plans, posted in Russian on the official government website on 30 December and signed off by prime minister Dmitry Medvedev, have been translated and reported by the independent Barents Observer newspaper, based in Norway.

The scale of the plans will alarm other Arctic nations, particularly Canada, the United States, Norway and Finland, which all have coastlines on the increasingly ice-free Arctic Ocean.

None of these has the powerful nuclear-propelled ships required to compete with Russia’s existing fleet, let alone the new ones it intends to build.

Although the Russian plans will not be completed until 2035, because the scale of shipbuilding alone is enormous, work has already begun and many of the preparations are going forward this year with a regional geological survey being conducted to pinpoint the riches to be exploited.

“In the 21st century, there will be a maritime ‘gold rush’ to the upper latitudes once conditions permit”

The Barents Observer reports that the plan builds on decrees issued by President Putin from May 2018, and a request to boost annual shipments on the Northern Sea Route across the top of Siberia to 80 million tons by 2024.

Although Rosatom, the giant state-controlled nuclear company, is leading the push to exploit the Arctic, and has already led the way with a floating nuclear power station to help provide power, there are a host of other leading Russian companies involved.

The fact that they are mostly involved in fossil fuel extraction and mineral mining will send a shiver down the spine of all those who believe that the Arctic should be left alone – and that exploiting its potential riches will ensure the destruction of much of the planet through climate change.

The Russians, on the other hand, see the Arctic as their own backyard and climate change as a way of gaining both economic and financial advantage, because Siberia will become much warmer.

Tax-free incentive

Enterprises involved include oil and gas companies Novatek, Gazprom Neft, Rosneft and the Independent Oil Company. In addition there are mineral and ore developers like Nornickel, VostokCoal, Baimskaya, KAZ Minerals, Vostok Engineering and Severnaya Zvezda.

The plans involve around 40 new vessels, several of them huge nuclear ice-breakers, designed to keep shipping lanes open in all circumstances. New railway lines, roads and bridges will be built in northern Siberia, with four airports upgraded to bring in supplies and people. Both companies and people will be encouraged by a special tax-free status for the region.

Exactly what is there to be exploited is not yet known. However, the Maritime Executive website has this to say: “What is generally understood is that there are vast resources to be harnessed. It is estimated that 30% of the world’s untapped hydrocarbons can be found in the Arctic, including a full 25% of proven hydrocarbon reserves.

“Much nickel, platinum, palladium, lead, diamonds, and other rare Earth metals are there as well. In the 21st century, there will be a maritime ‘gold rush’ to the upper latitudes once conditions permit.”

By coincidence the US Congressional Research Service put out an updated research paper on the Arctic on 20 December, discussing the tensions in the region.

American anxiety

Even before the latest Russian announcement there was concern in Washington that an Arctic takeover was planned. The document quotes US Secretary of State Michael Pompeo: “We’re concerned about Russia’s claim over the international waters of the Northern Sea Route, including its newly announced plans to connect it with China’s Maritime Silk Road.

“In the Northern Sea Route, Moscow already illegally demands other nations request permission to pass, requires Russian maritime pilots to be aboard foreign ships, and threatens to use military force to sink any that fail to comply with its demands.

“Just because the Arctic is a place of wilderness does not mean it should become a place of lawlessness. It need not be the case. And we stand ready to ensure that it does not become so.”

As the ice in the region melts, it is clear that the tensions will continue to grow. − Climate News Network

As the polar sea ice vanishes faster, Russia unveils plans to exploit Arctic riches: fossil fuel deposits, minerals and new shipping routes.

LONDON, 7 January, 2020 − The Russian government has published ambitious plans to exploit the Arctic riches off its northern coast, opening up the polar region to exploitation with a fleet of 40 ships, new roads and railways and four enlarged airports.

The plans, posted in Russian on the official government website on 30 December and signed off by prime minister Dmitry Medvedev, have been translated and reported by the independent Barents Observer newspaper, based in Norway.

The scale of the plans will alarm other Arctic nations, particularly Canada, the United States, Norway and Finland, which all have coastlines on the increasingly ice-free Arctic Ocean.

None of these has the powerful nuclear-propelled ships required to compete with Russia’s existing fleet, let alone the new ones it intends to build.

Although the Russian plans will not be completed until 2035, because the scale of shipbuilding alone is enormous, work has already begun and many of the preparations are going forward this year with a regional geological survey being conducted to pinpoint the riches to be exploited.

“In the 21st century, there will be a maritime ‘gold rush’ to the upper latitudes once conditions permit”

The Barents Observer reports that the plan builds on decrees issued by President Putin from May 2018, and a request to boost annual shipments on the Northern Sea Route across the top of Siberia to 80 million tons by 2024.

Although Rosatom, the giant state-controlled nuclear company, is leading the push to exploit the Arctic, and has already led the way with a floating nuclear power station to help provide power, there are a host of other leading Russian companies involved.

The fact that they are mostly involved in fossil fuel extraction and mineral mining will send a shiver down the spine of all those who believe that the Arctic should be left alone – and that exploiting its potential riches will ensure the destruction of much of the planet through climate change.

The Russians, on the other hand, see the Arctic as their own backyard and climate change as a way of gaining both economic and financial advantage, because Siberia will become much warmer.

Tax-free incentive

Enterprises involved include oil and gas companies Novatek, Gazprom Neft, Rosneft and the Independent Oil Company. In addition there are mineral and ore developers like Nornickel, VostokCoal, Baimskaya, KAZ Minerals, Vostok Engineering and Severnaya Zvezda.

The plans involve around 40 new vessels, several of them huge nuclear ice-breakers, designed to keep shipping lanes open in all circumstances. New railway lines, roads and bridges will be built in northern Siberia, with four airports upgraded to bring in supplies and people. Both companies and people will be encouraged by a special tax-free status for the region.

Exactly what is there to be exploited is not yet known. However, the Maritime Executive website has this to say: “What is generally understood is that there are vast resources to be harnessed. It is estimated that 30% of the world’s untapped hydrocarbons can be found in the Arctic, including a full 25% of proven hydrocarbon reserves.

“Much nickel, platinum, palladium, lead, diamonds, and other rare Earth metals are there as well. In the 21st century, there will be a maritime ‘gold rush’ to the upper latitudes once conditions permit.”

By coincidence the US Congressional Research Service put out an updated research paper on the Arctic on 20 December, discussing the tensions in the region.

American anxiety

Even before the latest Russian announcement there was concern in Washington that an Arctic takeover was planned. The document quotes US Secretary of State Michael Pompeo: “We’re concerned about Russia’s claim over the international waters of the Northern Sea Route, including its newly announced plans to connect it with China’s Maritime Silk Road.

“In the Northern Sea Route, Moscow already illegally demands other nations request permission to pass, requires Russian maritime pilots to be aboard foreign ships, and threatens to use military force to sink any that fail to comply with its demands.

“Just because the Arctic is a place of wilderness does not mean it should become a place of lawlessness. It need not be the case. And we stand ready to ensure that it does not become so.”

As the ice in the region melts, it is clear that the tensions will continue to grow. − Climate News Network

Little time left to arrest Greenland’s melting

Humans may still have time to stop Greenland’s melting, preventing Arctic ice sheet collapse and devastating sea level rise. But the time left may be short.

LONDON, 30 December, 2019 – It’s still possible, but it’s far from certain: stopping Greenland’s melting can be done, but it must be done soon.

Norwegian and US scientists have taken a close look at the ice age history of Greenland and come to a grim conclusion. All it takes to set the island’s ice cap melting away is a mean sea surface temperature higher than seven degrees Celsius. And the present mean sea surface temperature is already 7.7°C.

Greenland is the northern hemisphere’s single richest store of frozen water: the island’s bedrock holds enough to raise global sea levels by seven metres and drown or wash away the world’s coastal communities, including the great cities of New York and Miami, Shanghai and Kolkata, Amsterdam and London.

And the pattern of geological evidence – outlined in the Proceedings of the National Academy of Sciences – combined with climate models suggests that any sustained temperature rise could trigger an irreversible melt of the entire southern Greenland ice sheet.

The scientists suggest that the threshold for this calamity could be between 0.8°C above the post-Ice Age norm, and 3.2°C.

“The critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century”

In fact, because of profligate use of fossil fuels and the release of greenhouse gases into the atmosphere, the planet has already warmed by around 1°C above the level for most of human history, and warming of at least 3.2°C by the end of this century now seems almost certain.

Researchers publish their conclusions with the intention that they should be examined, tested, challenged and perhaps overturned. But widespread alarm at the rate of melt and mass loss in Greenland has been consistent and increasing with the years.

Researchers have repeatedly established that melting each summer is increasing the rate at which glaciers flow and deliver ice to increasingly warmer northern seas, and that this rate of melting has itself begun to accelerate.

So Nil Irvali of the University of Bergen and colleagues took a closer look at the story told by microfossils within cores from the ice and the ocean floor during four interglacial periods over the last 450,000 years.

During those warm spells ocean levels rose dramatically, and in two episodes Greenland’s vanishing ice could have contributed more than five metres in one case, and up to seven metres of sea level rise in the other.

Triggers identified

And in all four of those interglacials, conditions reached temperatures higher than they are right now.

Concern about the stability of the Greenland icecap is no surprise: the Arctic is already warming faster than anywhere else on the planet, thanks to profligate use of fossil fuels and the destruction of the rainforests, and researchers worldwide have begun to identify triggers that feed back into further warming: rain, for instance, in winter; the loss of cloud cover in summer; and the deposits of soot from polar wildfires that darken the snows and enhance the absorption of the sun’s rays.

Years ago, the phrase “at a glacial pace” ceased to be a valid cliché: US scientists clocked one river of ice moving at a rate of 46 metres a day.

So the new study simply confirms fears that already are widespread. What remains to be settled is the point at which the decline of the ice sheet becomes irreversible, the Bergen scientists say. As the ocean warms, this feeds back into the process of melting and triggers longer-term feedbacks.

“The exact point at which these feedbacks are triggered remains equivocal,” say Dr Irvali and her co-authors. “Notably, the critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century. The duration for which this threshold is exceeded will determine Greenland’s fate.” – Climate News Network

Humans may still have time to stop Greenland’s melting, preventing Arctic ice sheet collapse and devastating sea level rise. But the time left may be short.

LONDON, 30 December, 2019 – It’s still possible, but it’s far from certain: stopping Greenland’s melting can be done, but it must be done soon.

Norwegian and US scientists have taken a close look at the ice age history of Greenland and come to a grim conclusion. All it takes to set the island’s ice cap melting away is a mean sea surface temperature higher than seven degrees Celsius. And the present mean sea surface temperature is already 7.7°C.

Greenland is the northern hemisphere’s single richest store of frozen water: the island’s bedrock holds enough to raise global sea levels by seven metres and drown or wash away the world’s coastal communities, including the great cities of New York and Miami, Shanghai and Kolkata, Amsterdam and London.

And the pattern of geological evidence – outlined in the Proceedings of the National Academy of Sciences – combined with climate models suggests that any sustained temperature rise could trigger an irreversible melt of the entire southern Greenland ice sheet.

The scientists suggest that the threshold for this calamity could be between 0.8°C above the post-Ice Age norm, and 3.2°C.

“The critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century”

In fact, because of profligate use of fossil fuels and the release of greenhouse gases into the atmosphere, the planet has already warmed by around 1°C above the level for most of human history, and warming of at least 3.2°C by the end of this century now seems almost certain.

Researchers publish their conclusions with the intention that they should be examined, tested, challenged and perhaps overturned. But widespread alarm at the rate of melt and mass loss in Greenland has been consistent and increasing with the years.

Researchers have repeatedly established that melting each summer is increasing the rate at which glaciers flow and deliver ice to increasingly warmer northern seas, and that this rate of melting has itself begun to accelerate.

So Nil Irvali of the University of Bergen and colleagues took a closer look at the story told by microfossils within cores from the ice and the ocean floor during four interglacial periods over the last 450,000 years.

During those warm spells ocean levels rose dramatically, and in two episodes Greenland’s vanishing ice could have contributed more than five metres in one case, and up to seven metres of sea level rise in the other.

Triggers identified

And in all four of those interglacials, conditions reached temperatures higher than they are right now.

Concern about the stability of the Greenland icecap is no surprise: the Arctic is already warming faster than anywhere else on the planet, thanks to profligate use of fossil fuels and the destruction of the rainforests, and researchers worldwide have begun to identify triggers that feed back into further warming: rain, for instance, in winter; the loss of cloud cover in summer; and the deposits of soot from polar wildfires that darken the snows and enhance the absorption of the sun’s rays.

Years ago, the phrase “at a glacial pace” ceased to be a valid cliché: US scientists clocked one river of ice moving at a rate of 46 metres a day.

So the new study simply confirms fears that already are widespread. What remains to be settled is the point at which the decline of the ice sheet becomes irreversible, the Bergen scientists say. As the ocean warms, this feeds back into the process of melting and triggers longer-term feedbacks.

“The exact point at which these feedbacks are triggered remains equivocal,” say Dr Irvali and her co-authors. “Notably, the critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century. The duration for which this threshold is exceeded will determine Greenland’s fate.” – Climate News Network

Heat the Arctic to cool the Earth, scientists say

If we seriously want to tackle the climate crisis, here’s a drastic idea: we could heat the Arctic to cool the planet.

LONDON, 19 December, 2019 − With politicians failing to cut greenhouse gas emissions far and fast enough, the only hope may be to find a different way to cool the planet. One group of researchers has put forward an idea so different that critics may regard it as outlandish: heat the Arctic.

To heat the Arctic so much that the sea ice disappears even in the winter sounds like a weird idea. But the researchers believe it would have the beneficial effect of cooling the planet down.

They argue that with the Arctic ice already expected to disappear during the summer months within the next 30 years, and large increases in temperature and changes in the polar climate already certain, we should turn this radical shift to our advantage.

Their point is that since, at the current rate of progress, politicians seem unlikely to cut greenhouse gas emissions enough to prevent drastic temperature rise, humankind must find other ways to cool the Earth if it is to survive.

“Climate change is a major issue and all options should be considered when dealing with it”

Heating the planet in order to cool it is certainly counter-intuitive. But, whether or not the scheme could ever work, it shows the ingenuity and enterprise now being poured into stabilising global temperatures close to their historic level.

It also, of course, shows how horribly late we have left it to rein in the climate crisis, when wise and determined action 30 years ago could have achieved so much.

The idea proposed is, in principle, simple enough: to ensure that the warm currents of the Gulf Stream, known by science as the North Atlantic Oscillation (NAO) continue northwards across the Arctic Circle the whole year round. This would release massive amounts of heat from the ocean into the atmosphere and beyond that into space, so cooling the sea and ultimately the Earth.

“The Arctic Ocean ice cover works as a strong insulator, impeding the heat from the ocean below to warm up the atmosphere above. If this ice layer were however removed, the atmosphere would increase in temperature by around 20°C during the winter.

More heat escapes

“This increase in temperature would in turn increase the heat irradiated into space, thus cooling down the oceans,” explains the lead author of the study which details the proposal, published in the journal SN Applied Sciences. He is Julian Hunt, a postdoctoral research scholar at IIASA, the International Institute for Applied Systems Analysis.

The problem that needs to be overcome is that very cold and only mildly salty water currently floats on the surface of the Arctic Ocean, freezing in the winter and capturing the warmth of the water in the ocean depths.

The authors say the main factor helping to maintain the Arctic sea ice cover is the fact that the top 100 metres of the ocean is less saline than the Atlantic, preventing the Atlantic from flowing above the cold Arctic waters. Increasing the salinity of the Arctic Ocean’s surface, they say, would let the warmer and less salty North Atlantic current flow over it, warming the atmosphere considerably and releasing the ocean heat trapped under the ice.

They suggest three ways to keep fresh water out of the Arctic. The first would divert the big rivers of North America and Siberia southwards to prevent them draining into the polar ocean. The second would place submerged obstructions in front of the rapidly melting Greenland glaciers, to slow the speed of the ice sheets’ melting, while the third would use a solar- and wind-powered icebreaker to pump cold, near-fresh water deeper into the ocean to mix with the saltier water below, allowing the warmer currents to sweep in from the south.

Unknown consequences

Dr Hunt and his colleagues say there could be terrific benefits. Shipping could navigate the ice-free Arctic Ocean all year round, cutting journey times between Asia, Europe and North America. The need for heating homes in the northern hemisphere during the winter would be drastically reduced, because their plan would raise air temperatures by as much as 20°C.

But the massive interference with natural systems in the Arctic would also have its downside. The rapid year-round rise in temperature would dramatically increase the melting of Greenland and therefore of sea level rise the world over. The effect on the northern hemisphere climate, particularly much increased rainfall with a warmer sea and atmosphere, is impossible to predict.

But Dr Hunt says that while there are clearly huge risks, the world is already heading for uncharted waters, so humans must do something drastic. “Although it is important to mitigate the impacts from climate change with the reduction in CO2 emissions, we should also think of ways to adapt the world to the new climate conditions to avoid uncontrollable, unpredictable and destructive climate change resulting in socio-economic and environmental collapse.

“Climate change is a major issue and all options should be considered when dealing with it.” − Climate News Network

If we seriously want to tackle the climate crisis, here’s a drastic idea: we could heat the Arctic to cool the planet.

LONDON, 19 December, 2019 − With politicians failing to cut greenhouse gas emissions far and fast enough, the only hope may be to find a different way to cool the planet. One group of researchers has put forward an idea so different that critics may regard it as outlandish: heat the Arctic.

To heat the Arctic so much that the sea ice disappears even in the winter sounds like a weird idea. But the researchers believe it would have the beneficial effect of cooling the planet down.

They argue that with the Arctic ice already expected to disappear during the summer months within the next 30 years, and large increases in temperature and changes in the polar climate already certain, we should turn this radical shift to our advantage.

Their point is that since, at the current rate of progress, politicians seem unlikely to cut greenhouse gas emissions enough to prevent drastic temperature rise, humankind must find other ways to cool the Earth if it is to survive.

“Climate change is a major issue and all options should be considered when dealing with it”

Heating the planet in order to cool it is certainly counter-intuitive. But, whether or not the scheme could ever work, it shows the ingenuity and enterprise now being poured into stabilising global temperatures close to their historic level.

It also, of course, shows how horribly late we have left it to rein in the climate crisis, when wise and determined action 30 years ago could have achieved so much.

The idea proposed is, in principle, simple enough: to ensure that the warm currents of the Gulf Stream, known by science as the North Atlantic Oscillation (NAO) continue northwards across the Arctic Circle the whole year round. This would release massive amounts of heat from the ocean into the atmosphere and beyond that into space, so cooling the sea and ultimately the Earth.

“The Arctic Ocean ice cover works as a strong insulator, impeding the heat from the ocean below to warm up the atmosphere above. If this ice layer were however removed, the atmosphere would increase in temperature by around 20°C during the winter.

More heat escapes

“This increase in temperature would in turn increase the heat irradiated into space, thus cooling down the oceans,” explains the lead author of the study which details the proposal, published in the journal SN Applied Sciences. He is Julian Hunt, a postdoctoral research scholar at IIASA, the International Institute for Applied Systems Analysis.

The problem that needs to be overcome is that very cold and only mildly salty water currently floats on the surface of the Arctic Ocean, freezing in the winter and capturing the warmth of the water in the ocean depths.

The authors say the main factor helping to maintain the Arctic sea ice cover is the fact that the top 100 metres of the ocean is less saline than the Atlantic, preventing the Atlantic from flowing above the cold Arctic waters. Increasing the salinity of the Arctic Ocean’s surface, they say, would let the warmer and less salty North Atlantic current flow over it, warming the atmosphere considerably and releasing the ocean heat trapped under the ice.

They suggest three ways to keep fresh water out of the Arctic. The first would divert the big rivers of North America and Siberia southwards to prevent them draining into the polar ocean. The second would place submerged obstructions in front of the rapidly melting Greenland glaciers, to slow the speed of the ice sheets’ melting, while the third would use a solar- and wind-powered icebreaker to pump cold, near-fresh water deeper into the ocean to mix with the saltier water below, allowing the warmer currents to sweep in from the south.

Unknown consequences

Dr Hunt and his colleagues say there could be terrific benefits. Shipping could navigate the ice-free Arctic Ocean all year round, cutting journey times between Asia, Europe and North America. The need for heating homes in the northern hemisphere during the winter would be drastically reduced, because their plan would raise air temperatures by as much as 20°C.

But the massive interference with natural systems in the Arctic would also have its downside. The rapid year-round rise in temperature would dramatically increase the melting of Greenland and therefore of sea level rise the world over. The effect on the northern hemisphere climate, particularly much increased rainfall with a warmer sea and atmosphere, is impossible to predict.

But Dr Hunt says that while there are clearly huge risks, the world is already heading for uncharted waters, so humans must do something drastic. “Although it is important to mitigate the impacts from climate change with the reduction in CO2 emissions, we should also think of ways to adapt the world to the new climate conditions to avoid uncontrollable, unpredictable and destructive climate change resulting in socio-economic and environmental collapse.

“Climate change is a major issue and all options should be considered when dealing with it.” − Climate News Network

Racing ice loss strips Greenland of mass

Greenland is shrinking, losing ice seven times faster than a generation ago. Scientists have taken a new and ominous measure of polar loss.

LONDON, 11 December, 2019 – Greenland – the largest body of frozen water in the northern hemisphere – is now losing ice seven times faster than it did during the last decade of the 20th century.

From 1990 to 1999, the Greenland ice sheet spilled an average of 33 billion tonnes of ice into the oceans every year. In the last decade the rate of loss has accelerated to an average of 254 billion tonnes a year.

Altogether, the Greenland ice cap has surrendered 3.8 trillion tonnes of ice since 1992. This alone is enough to raise global sea levels by 10.6 millimetres.

Glaciers and icecaps are in retreat in two hemispheres, and on every continent, as a consequence of profligate human combustion of fossil fuels, to drive up greenhouse gas levels in the atmosphere, and accelerate global heating.

Devastating

“As a rule of thumb, for every centimetre rise in global sea level another six million people are exposed to coastal flooding around the planet”, said Andrew Shepherd of the University of Leeds in the UK.

“On current trends, Greenland ice melting will cause 100 million people to be flooded each year by the end of the century, so 400 million in total due to all sea level rise. These are not unlikely events of small impacts; they are happening and will be devastating for coastal communities.”

Professor Shepherd is one of 96 polar scientists from 50 international organisations in a partnership known by the cumbrous name IMBIE, which stands for Ice Sheet Mass Balance Intercomparison Exercise. They made this assessment, based on data from 11 satellite missions and 26 separate surveys between 1992 and 2018, and published their conclusions in the journal Nature.

Greenland is not just the largest ice mass in the Arctic, it is probably the polar landscape studied for the longest time, and the most intensively.
Researchers have monitored the rate of summer melt, tried to match increases with other phenomena – for instance the darkening of snow by sub-Arctic wildfires – and tried to explore the mechanisms by which volumes of water that might in the past have frozen again each winter now accelerate glacier melt and escape into the ocean.

No surprise

The icecap is so big that – were it all to melt, which would take centuries – it would raise sea levels by as much as seven metres.

The news of a dramatic increase in rates of melting is not a surprise, and certainly not to the people who live in Greenland.

In 2013, the Intergovernmental Panel on Climate Change warned that global sea levels would rise by 60 cms by 2100. What matters about the latest survey is that it confirms the worst fears of many climate scientists and suggests that sea level rise is heading for the high end of the 2013 projections.

That is, by the end of this century, seas could have risen by nearer 70 cms. Around 100 million people already live at levels below the highest tides: the numbers increasingly at risk may be much higher.

The same study also explores the rates of change. Although the warmest years ever recorded have happened in the last century, as fossil fuel emissions and rainforest losses have continued to increase, the impact of global heating has been uneven.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale”

The greatest loss of Greenland ice in any one year was in 2011, when the island lost 335 billion tonnes. Nor does the survey include all the data from 2019, and researchers could yet find that this summer’s ice loss has set new records.

Greenland’s loss of ice has been mirrored by continued loss of sea ice during successive Arctic summers, and since the world’s seasonal weather patterns have – for most of human history – been driven by the temperature difference between tropics and poles, the continued loss of ice will almost certainly impose worldwide costs in harvest losses, freak storms, droughts, wildfires and of course coastal flooding.

And ultimately, the study is a test of computer simulations of change in the northern hemisphere. Climate models have consistently predicted polar ice loss and sea level rise. But the latest study is a confirmation that such loss is real, and beyond argument.

“While computer simulation allows us to make projections from climate change scenarios, the satellite measurements provide prima facie, rather irrefutable evidence,” said Erik Ivins of Nasa’s Jet Propulsion Laboratory in California, and a co-author.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale.” – Climate News Network

Greenland is shrinking, losing ice seven times faster than a generation ago. Scientists have taken a new and ominous measure of polar loss.

LONDON, 11 December, 2019 – Greenland – the largest body of frozen water in the northern hemisphere – is now losing ice seven times faster than it did during the last decade of the 20th century.

From 1990 to 1999, the Greenland ice sheet spilled an average of 33 billion tonnes of ice into the oceans every year. In the last decade the rate of loss has accelerated to an average of 254 billion tonnes a year.

Altogether, the Greenland ice cap has surrendered 3.8 trillion tonnes of ice since 1992. This alone is enough to raise global sea levels by 10.6 millimetres.

Glaciers and icecaps are in retreat in two hemispheres, and on every continent, as a consequence of profligate human combustion of fossil fuels, to drive up greenhouse gas levels in the atmosphere, and accelerate global heating.

Devastating

“As a rule of thumb, for every centimetre rise in global sea level another six million people are exposed to coastal flooding around the planet”, said Andrew Shepherd of the University of Leeds in the UK.

“On current trends, Greenland ice melting will cause 100 million people to be flooded each year by the end of the century, so 400 million in total due to all sea level rise. These are not unlikely events of small impacts; they are happening and will be devastating for coastal communities.”

Professor Shepherd is one of 96 polar scientists from 50 international organisations in a partnership known by the cumbrous name IMBIE, which stands for Ice Sheet Mass Balance Intercomparison Exercise. They made this assessment, based on data from 11 satellite missions and 26 separate surveys between 1992 and 2018, and published their conclusions in the journal Nature.

Greenland is not just the largest ice mass in the Arctic, it is probably the polar landscape studied for the longest time, and the most intensively.
Researchers have monitored the rate of summer melt, tried to match increases with other phenomena – for instance the darkening of snow by sub-Arctic wildfires – and tried to explore the mechanisms by which volumes of water that might in the past have frozen again each winter now accelerate glacier melt and escape into the ocean.

No surprise

The icecap is so big that – were it all to melt, which would take centuries – it would raise sea levels by as much as seven metres.

The news of a dramatic increase in rates of melting is not a surprise, and certainly not to the people who live in Greenland.

In 2013, the Intergovernmental Panel on Climate Change warned that global sea levels would rise by 60 cms by 2100. What matters about the latest survey is that it confirms the worst fears of many climate scientists and suggests that sea level rise is heading for the high end of the 2013 projections.

That is, by the end of this century, seas could have risen by nearer 70 cms. Around 100 million people already live at levels below the highest tides: the numbers increasingly at risk may be much higher.

The same study also explores the rates of change. Although the warmest years ever recorded have happened in the last century, as fossil fuel emissions and rainforest losses have continued to increase, the impact of global heating has been uneven.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale”

The greatest loss of Greenland ice in any one year was in 2011, when the island lost 335 billion tonnes. Nor does the survey include all the data from 2019, and researchers could yet find that this summer’s ice loss has set new records.

Greenland’s loss of ice has been mirrored by continued loss of sea ice during successive Arctic summers, and since the world’s seasonal weather patterns have – for most of human history – been driven by the temperature difference between tropics and poles, the continued loss of ice will almost certainly impose worldwide costs in harvest losses, freak storms, droughts, wildfires and of course coastal flooding.

And ultimately, the study is a test of computer simulations of change in the northern hemisphere. Climate models have consistently predicted polar ice loss and sea level rise. But the latest study is a confirmation that such loss is real, and beyond argument.

“While computer simulation allows us to make projections from climate change scenarios, the satellite measurements provide prima facie, rather irrefutable evidence,” said Erik Ivins of Nasa’s Jet Propulsion Laboratory in California, and a co-author.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale.” – Climate News Network

Greenland ice melt feeds glacier instability

In a runaway effect, the Greenland ice melt lets surface water gurgle down to the bedrock – and at unexpected speeds.

LONDON, 6 December, 2019 – British scientists have caught a huge ice sheet in the act of draining away, with significant effects on its surroundings: they have seen what happens to the water created by the Greenland ice melt.

For the first time – and with help from drones – researchers have witnessed water flowing at a million cubic metres an hour from the surface of ice sheets through caverns in the ice and down to the glacial bedrock.

The study does not change the big picture of increasingly rapid melt as greenhouse gases build up in the atmosphere, and ever more of the northern hemisphere’s biggest ice cap flows downhill to raise global sea levels.

But it does throw light on the mechanisms by which glaciers turn to sea water, and it does suggest that many estimates of melt rate so far might prove to be under-estimates.

Greenland is the planet’s second largest ice sheet and the biggest single contributor to global sea level rise. Researchers have been alarmed for years about the increasing rate of summer melt and the accelerating speed of what had once been imperceptible glacial flows.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere, but the overall effect is in fact very significant”

And researchers from the universities of Cambridge, Aberystwyth and Lancaster have now been able to put a measure on water surface loss.

They report in the Proceedings of the National Academy of Sciences that they used custom-built aerial drones and complex computer modelling to work out how fractures form below vast lakes of meltwater that collect on the surface of the Store Glacier on the island’s northwestern sheet.

They watched splits form in the glacial ice, to suddenly open up an escape route for the supraglacial pool. As they watched, such fractures became caverns called moulins, down which in one case five million cubic metres of water – think of 2,000 Olympic swimming pools – flowed in just five hours.

The ice of the glacier is typically a kilometre thick, so the scientists may have observed the planet’s longest waterfall. And as the ice drained away to the bottom of the ice sheet, it may have served as a lubricant to speed up glacier flow over the bedrock.

The ice sheet lifted by half a metre, presumably in response to the sub-surface flood, and four kilometres downstream glacial speed picked up from a speed of two metres to more than five metres a day.

Daily billion-tonne loss

“It’s possible we’ve under-estimated the effects of these glaciers on the overall instability of the Greenland ice sheet. It’s a rare thing to observe these fast-draining lakes – we were lucky to be in the right place at the right time,” said Tom Chudley, of the Scott Polar Research Institute in Cambridge, one of the authors.

Until now, scientists have been able to estimate glacial flow and surface melt only by satellite studies – which reveal little of the detail – or direct on-the-ground measurement under conditions that are difficult even in good weather.

But even with these constraints researchers have been able to calculate the shrinkage of the Greenland ice sheet at the rate of a billion tonnes a day, as temperatures rise in response to ever-increasing use of fossil fuels around the globe.

The next step is to deploy drilling equipment for a closer look at how the water gets below the glacier to reach the bedrock, and calculate how the ice sheet may change not just over hours but over the coming decades as well.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere,” said Poul Christofferson, who led the project, “but the overall effect is in fact very significant.” – Climate News Network

In a runaway effect, the Greenland ice melt lets surface water gurgle down to the bedrock – and at unexpected speeds.

LONDON, 6 December, 2019 – British scientists have caught a huge ice sheet in the act of draining away, with significant effects on its surroundings: they have seen what happens to the water created by the Greenland ice melt.

For the first time – and with help from drones – researchers have witnessed water flowing at a million cubic metres an hour from the surface of ice sheets through caverns in the ice and down to the glacial bedrock.

The study does not change the big picture of increasingly rapid melt as greenhouse gases build up in the atmosphere, and ever more of the northern hemisphere’s biggest ice cap flows downhill to raise global sea levels.

But it does throw light on the mechanisms by which glaciers turn to sea water, and it does suggest that many estimates of melt rate so far might prove to be under-estimates.

Greenland is the planet’s second largest ice sheet and the biggest single contributor to global sea level rise. Researchers have been alarmed for years about the increasing rate of summer melt and the accelerating speed of what had once been imperceptible glacial flows.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere, but the overall effect is in fact very significant”

And researchers from the universities of Cambridge, Aberystwyth and Lancaster have now been able to put a measure on water surface loss.

They report in the Proceedings of the National Academy of Sciences that they used custom-built aerial drones and complex computer modelling to work out how fractures form below vast lakes of meltwater that collect on the surface of the Store Glacier on the island’s northwestern sheet.

They watched splits form in the glacial ice, to suddenly open up an escape route for the supraglacial pool. As they watched, such fractures became caverns called moulins, down which in one case five million cubic metres of water – think of 2,000 Olympic swimming pools – flowed in just five hours.

The ice of the glacier is typically a kilometre thick, so the scientists may have observed the planet’s longest waterfall. And as the ice drained away to the bottom of the ice sheet, it may have served as a lubricant to speed up glacier flow over the bedrock.

The ice sheet lifted by half a metre, presumably in response to the sub-surface flood, and four kilometres downstream glacial speed picked up from a speed of two metres to more than five metres a day.

Daily billion-tonne loss

“It’s possible we’ve under-estimated the effects of these glaciers on the overall instability of the Greenland ice sheet. It’s a rare thing to observe these fast-draining lakes – we were lucky to be in the right place at the right time,” said Tom Chudley, of the Scott Polar Research Institute in Cambridge, one of the authors.

Until now, scientists have been able to estimate glacial flow and surface melt only by satellite studies – which reveal little of the detail – or direct on-the-ground measurement under conditions that are difficult even in good weather.

But even with these constraints researchers have been able to calculate the shrinkage of the Greenland ice sheet at the rate of a billion tonnes a day, as temperatures rise in response to ever-increasing use of fossil fuels around the globe.

The next step is to deploy drilling equipment for a closer look at how the water gets below the glacier to reach the bedrock, and calculate how the ice sheet may change not just over hours but over the coming decades as well.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere,” said Poul Christofferson, who led the project, “but the overall effect is in fact very significant.” – Climate News Network

Arctic’s oldest ice shows signs of change

There’s change afoot even where scientists least expect it, among the Arctic’s oldest ice. If it goes, so does the wildlife.

LONDON, 21 November, 2019 – Stretches of the Arctic’s oldest ice, and its thickest – the last refuge ice that should survive even when the Arctic Ocean technically becomes ice-free in summers later this century – are now disappearing twice as fast as the rest of the Arctic icecap.

Although the north polar ice is vulnerable to global heating, and has been thinning and retreating at an accelerating rate for the last 40 summers, researchers have always expected some winter ice to survive: they define an “ice-free Arctic Ocean” as one with less than 1 million square kilometres of surviving ice pack.

But this supposedly ancient remnant of the polar winters, concentrated north of Greenland and the Canadian polar archipelago, is showing signs of change.

Researchers do not explicitly finger climate change driven by ever-greater human use of fossil fuels as the direct agent of this change: this is an area of polar ice difficult to observe and explore, is little known, and may always have been subject to change.

“This area will be a refuge where species can survive and hopefully expand their regions once the ice starts returning”

But scientists know why it is important. From submarine algae to polar bears, an entire Arctic ecosystem is dependent on the ice sheet. As the ice disappears, so will the seals, and their predators too.

Conservation-minded governments that want to establish protected areas need to know where protection will work best. “Eventually, the Last Ice Area will be the region that will repopulate the Arctic with wildlife,” said Kent Moore of the University of Toronto in Canada. “This area will be a refuge where species can survive and hopefully expand their regions once the ice starts returning.”

Dr Moore and his colleagues report in the journal Geophysical Research Letters that they used computer models and satellite observation data to build up a picture of what they call “spatiotemporal variability” in their Last Ice Area.

They found two distinct places where ice thickness fluctuated by up to 1.2 metres from year to year. In some patches, the ice was thinning by the decade: a loss of 1.5 metres since the late 1970s.

No monolith

Most north polar ice is youthful: seldom more than four years old. The Last Ice Area is certainly more than five years old, and has been measured at a thickness of four metres. It is not a static region: ice moves with the ocean beneath it.

And even the levels of melting are affected by natural cyclic ocean shifts as well as higher temperatures fuelled by greenhouse gas build-up in the atmosphere.

The race is on to understand the forces at work in what might be – one day – the only surviving ice in the polar summer.

“We can’t treat the Last Ice Area as a monolithic area of ice which is going to last a long time,” said Dr Moore. “There’s actually lots of regional variability.” – Climate News Network

There’s change afoot even where scientists least expect it, among the Arctic’s oldest ice. If it goes, so does the wildlife.

LONDON, 21 November, 2019 – Stretches of the Arctic’s oldest ice, and its thickest – the last refuge ice that should survive even when the Arctic Ocean technically becomes ice-free in summers later this century – are now disappearing twice as fast as the rest of the Arctic icecap.

Although the north polar ice is vulnerable to global heating, and has been thinning and retreating at an accelerating rate for the last 40 summers, researchers have always expected some winter ice to survive: they define an “ice-free Arctic Ocean” as one with less than 1 million square kilometres of surviving ice pack.

But this supposedly ancient remnant of the polar winters, concentrated north of Greenland and the Canadian polar archipelago, is showing signs of change.

Researchers do not explicitly finger climate change driven by ever-greater human use of fossil fuels as the direct agent of this change: this is an area of polar ice difficult to observe and explore, is little known, and may always have been subject to change.

“This area will be a refuge where species can survive and hopefully expand their regions once the ice starts returning”

But scientists know why it is important. From submarine algae to polar bears, an entire Arctic ecosystem is dependent on the ice sheet. As the ice disappears, so will the seals, and their predators too.

Conservation-minded governments that want to establish protected areas need to know where protection will work best. “Eventually, the Last Ice Area will be the region that will repopulate the Arctic with wildlife,” said Kent Moore of the University of Toronto in Canada. “This area will be a refuge where species can survive and hopefully expand their regions once the ice starts returning.”

Dr Moore and his colleagues report in the journal Geophysical Research Letters that they used computer models and satellite observation data to build up a picture of what they call “spatiotemporal variability” in their Last Ice Area.

They found two distinct places where ice thickness fluctuated by up to 1.2 metres from year to year. In some patches, the ice was thinning by the decade: a loss of 1.5 metres since the late 1970s.

No monolith

Most north polar ice is youthful: seldom more than four years old. The Last Ice Area is certainly more than five years old, and has been measured at a thickness of four metres. It is not a static region: ice moves with the ocean beneath it.

And even the levels of melting are affected by natural cyclic ocean shifts as well as higher temperatures fuelled by greenhouse gas build-up in the atmosphere.

The race is on to understand the forces at work in what might be – one day – the only surviving ice in the polar summer.

“We can’t treat the Last Ice Area as a monolithic area of ice which is going to last a long time,” said Dr Moore. “There’s actually lots of regional variability.” – Climate News Network