Category Archives: Oceans

Blue energy revolution comes of age

With green energy from wind and solar out-competing fossil fuels, governments now hope for another boost − blue energy from the oceans.

LONDON, 31 March, 2020 − The amount of energy generated by tides and waves in the last decade has increased 10-fold. Now governments around the world are planning to scale up these ventures to tap into the oceans’ vast store of blue energy.

Although in 2019 the total amount of energy produced by “blue power” would have been enough to provide electricity to only one city the size of Paris, even that was a vast increase on the tiny experiments being carried out 10 years earlier.

Now countries across the world with access to the sea are beginning to exploit all sorts of new technologies and intending to scale them up to bolster their attempts to go carbon-neutral.

Blue energy takes many forms. One of the most difficult technically is harnessing the energy of waves with devices that produce electricity. After several false starts many successful prototypes are now being trialled for commercial use. Other experiments exploit the tidal range – using the power of rapidly rising and falling tidal streams to push water through turbines.

The most commercially successful strategies so far use underwater turbines, similar to wind turbines, to exploit the tidal currents in coastal regions.

More ambitious but along the same lines are attempts to capture the energy from the immense ocean currents that move vast quantities of water round the planet.

“Our latest report underlines the considerable international support for the marine renewable sector. The start of this new decade carries considerable promise for ocean energy”

Also included in blue energy is ocean thermal energy conversion, which exploits the temperature differences between solar energy stored as heat in the upper ocean layers and colder seawater, generally at a depth below 1000 metres.

A variation on this is to use salinity gradients, the difference between the salt content of the sea and fresh water entering from a large river system. Some of these schemes are being used to produce fresh drinking water for dry regions rather than electricity.

The potential from all these energy sources is so great that an organisation called Ocean Energy Systems (OES), an offshoot of the International Energy Agency, is pooling all the research in a bid to achieve large-scale deployment.

There are now 24 countries in the OES, including China, India, the US, most European nations with a coastline, Japan, Australia and South Africa. Most of them have already deployed some blue energy schemes and are hoping to scale them up to full commercial use in the next decade.

As with wind and solar when they were being widely developed ten years ago, energy from the oceans is currently more expensive than fossil fuels. But as the technologies are refined the costs are coming down.

Profiting already

Already China has encouraged tidal stream energy by offering a feed-in tariff three times the price of fossil fuels, similar to the rate used in many countries to launch solar and wind power. One Chinese company is already finding this incentive enough to feed power into the grid and make a profit.

Among the leading countries developing these technologies are Canada and the United Kingdom, the two countries with the highest tides in the world. Canada has a number of tidal energy schemes on its Atlantic coast in Nova Scotia, with several competing companies testing different prototypes.

Scotland, which has enormous potential because of its many islands and tidal currents, has the largest tidal array of underwater turbines in the world. The turbine output has exceeded expectations, and the MeyGen company is planning to vastly increase the number of installations.

But this is only one of more than 20 projects in the UK, some still in the research and development stage, but many already being scaled up for deployment at special testing grounds in Scotland’s Orkney islands and the West of England.

OES chairman Henry Jeffrey, from the University of Edinburgh, said the group’s new annual report communicates the sizeable global effort to identify commercialisation pathways for ocean energy technologies.

Both Canada and the US can now see big potential, and political leaders across Europe have identified ocean energy as an essential component in meeting decarbonisation targets, fostering economic growth and creating future employment opportunities.

Lower costs essential

“Our latest report underlines the considerable international support for the marine renewable sector as leading global powers attempt to rebalance energy usage and limit global warming. The start of this new decade carries considerable promise for ocean energy,” he said.

However, Jeffrey warned that while the sector continued to take huge strides forward, there were several challenges ahead “centred around affordability, reliability, installability, operability, funding availability, capacity building and standardisation.

“In particular, significant cost reductions are required for ocean energy technologies to compete with other low-carbon technologies.”

Currently the cost of wind power, taking into account construction costs over the turbines’ lifetime, is being quoted as around €0.8-10 (one eighth to one tenth of a Euro, about £0.07-9 or US$0.9-11) per kilowatt hour, but this is still going down.

The European target is to get tidal stream energy down to €0.10 by 2030 and wave power down to €0.15, which would also make them competitive with fossil fuels if gas and coal were obliged to pay for capturing and storing the carbon dioxide they produce. − Climate News Network

With green energy from wind and solar out-competing fossil fuels, governments now hope for another boost − blue energy from the oceans.

LONDON, 31 March, 2020 − The amount of energy generated by tides and waves in the last decade has increased 10-fold. Now governments around the world are planning to scale up these ventures to tap into the oceans’ vast store of blue energy.

Although in 2019 the total amount of energy produced by “blue power” would have been enough to provide electricity to only one city the size of Paris, even that was a vast increase on the tiny experiments being carried out 10 years earlier.

Now countries across the world with access to the sea are beginning to exploit all sorts of new technologies and intending to scale them up to bolster their attempts to go carbon-neutral.

Blue energy takes many forms. One of the most difficult technically is harnessing the energy of waves with devices that produce electricity. After several false starts many successful prototypes are now being trialled for commercial use. Other experiments exploit the tidal range – using the power of rapidly rising and falling tidal streams to push water through turbines.

The most commercially successful strategies so far use underwater turbines, similar to wind turbines, to exploit the tidal currents in coastal regions.

More ambitious but along the same lines are attempts to capture the energy from the immense ocean currents that move vast quantities of water round the planet.

“Our latest report underlines the considerable international support for the marine renewable sector. The start of this new decade carries considerable promise for ocean energy”

Also included in blue energy is ocean thermal energy conversion, which exploits the temperature differences between solar energy stored as heat in the upper ocean layers and colder seawater, generally at a depth below 1000 metres.

A variation on this is to use salinity gradients, the difference between the salt content of the sea and fresh water entering from a large river system. Some of these schemes are being used to produce fresh drinking water for dry regions rather than electricity.

The potential from all these energy sources is so great that an organisation called Ocean Energy Systems (OES), an offshoot of the International Energy Agency, is pooling all the research in a bid to achieve large-scale deployment.

There are now 24 countries in the OES, including China, India, the US, most European nations with a coastline, Japan, Australia and South Africa. Most of them have already deployed some blue energy schemes and are hoping to scale them up to full commercial use in the next decade.

As with wind and solar when they were being widely developed ten years ago, energy from the oceans is currently more expensive than fossil fuels. But as the technologies are refined the costs are coming down.

Profiting already

Already China has encouraged tidal stream energy by offering a feed-in tariff three times the price of fossil fuels, similar to the rate used in many countries to launch solar and wind power. One Chinese company is already finding this incentive enough to feed power into the grid and make a profit.

Among the leading countries developing these technologies are Canada and the United Kingdom, the two countries with the highest tides in the world. Canada has a number of tidal energy schemes on its Atlantic coast in Nova Scotia, with several competing companies testing different prototypes.

Scotland, which has enormous potential because of its many islands and tidal currents, has the largest tidal array of underwater turbines in the world. The turbine output has exceeded expectations, and the MeyGen company is planning to vastly increase the number of installations.

But this is only one of more than 20 projects in the UK, some still in the research and development stage, but many already being scaled up for deployment at special testing grounds in Scotland’s Orkney islands and the West of England.

OES chairman Henry Jeffrey, from the University of Edinburgh, said the group’s new annual report communicates the sizeable global effort to identify commercialisation pathways for ocean energy technologies.

Both Canada and the US can now see big potential, and political leaders across Europe have identified ocean energy as an essential component in meeting decarbonisation targets, fostering economic growth and creating future employment opportunities.

Lower costs essential

“Our latest report underlines the considerable international support for the marine renewable sector as leading global powers attempt to rebalance energy usage and limit global warming. The start of this new decade carries considerable promise for ocean energy,” he said.

However, Jeffrey warned that while the sector continued to take huge strides forward, there were several challenges ahead “centred around affordability, reliability, installability, operability, funding availability, capacity building and standardisation.

“In particular, significant cost reductions are required for ocean energy technologies to compete with other low-carbon technologies.”

Currently the cost of wind power, taking into account construction costs over the turbines’ lifetime, is being quoted as around €0.8-10 (one eighth to one tenth of a Euro, about £0.07-9 or US$0.9-11) per kilowatt hour, but this is still going down.

The European target is to get tidal stream energy down to €0.10 by 2030 and wave power down to €0.15, which would also make them competitive with fossil fuels if gas and coal were obliged to pay for capturing and storing the carbon dioxide they produce. − Climate News Network

Polar ice melt raises sea level dangers

polar ice

Greenland’s polar ice is now melting far faster than 30 years ago, Antarctic ice is retreating at an accelerating rate, and sea levels are creeping up.

LONDON, 19 March, 2020 – Greenland and Antarctica, the two greatest stores of frozen water on the planet, are now losing polar ice at a rate at least six times faster than they were at the close of the last century.

The fact that polar ice is melting ever faster has been clear for a decade, but the latest research is authoritative.

To establish the rate of loss, 89 polar scientists from 50 of the world’s great research institutions looked at data from 26 separate surveys between 1992 and 2018, along with information from 11 different satellite missions.

Gloomiest forecasts

And the finding is in line with the worst-case scenarios considered by the Intergovernmental Panel on Climate Change (IPCC). If this rate of increase continues, sea levels at the close of this century will be at least 17 centimetres higher than the gloomiest official forecasts so far.

Between 1992 and 2017, the global sea level rose by 17.8 millimetres, as 6.4 trillion tonnes of polar ice turned to water and trickled into the oceans – 10.6 mm from Greenland and 7.2 mm from Antarctica.

In the last decade of the last century, the northern and southern icecaps dwindled at the rate of 81 billion tonnes a year. In the last decade, this had risen to 475 billion tonnes a year. This means that a third of all sea level rise is now caused by the loss of polar ice.

The most recent assessment by the IPCC is that, by 2100, sea levels will have risen by 53 cms, putting 360 million people who live at sea level at some risk.

“This would mean 400 million people at risk of annual coastal flooding by 2100”

But the latest finding from the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) scientists is that seas will rise even higher, and even more people will have to move.

“Every centimetre of sea level rise leads to coastal flooding and coastal erosion, disrupting people’s lives around the planet,” said Andrew Shepherd, professor of Earth observation at the University of Leeds, UK, as he and colleagues published their findings of Greenland losses in Nature journal.

“If Antarctica and Greenland continue to track the worst-case climate warning scenario, they will cause an extra 17 cms of sea level rise by the end of the century.

“This would mean 400 million people at risk of annual coastal flooding by 2100. These are not unlikely events with small impacts; they are already under way and will be devastating for coastal communities.”

Global picture

Professor Shepherd and his IMBIE colleagues established almost two years ago that Antarctica was losing ice at an ever-accelerating rate, but the Greenland survey completes the global picture.

And it remains a picture in which the Arctic seems to be warming at an accelerating rate and sea levels seem to be rising ever faster.

This is not just because the polar ice caps are melting, but also because, almost everywhere, mountain glaciers are in retreat, and the oceans are expanding as sea temperatures rise in response to the steady warming of the planetary atmosphere. – Climate News Network

Greenland’s polar ice is now melting far faster than 30 years ago, Antarctic ice is retreating at an accelerating rate, and sea levels are creeping up.

LONDON, 19 March, 2020 – Greenland and Antarctica, the two greatest stores of frozen water on the planet, are now losing polar ice at a rate at least six times faster than they were at the close of the last century.

The fact that polar ice is melting ever faster has been clear for a decade, but the latest research is authoritative.

To establish the rate of loss, 89 polar scientists from 50 of the world’s great research institutions looked at data from 26 separate surveys between 1992 and 2018, along with information from 11 different satellite missions.

Gloomiest forecasts

And the finding is in line with the worst-case scenarios considered by the Intergovernmental Panel on Climate Change (IPCC). If this rate of increase continues, sea levels at the close of this century will be at least 17 centimetres higher than the gloomiest official forecasts so far.

Between 1992 and 2017, the global sea level rose by 17.8 millimetres, as 6.4 trillion tonnes of polar ice turned to water and trickled into the oceans – 10.6 mm from Greenland and 7.2 mm from Antarctica.

In the last decade of the last century, the northern and southern icecaps dwindled at the rate of 81 billion tonnes a year. In the last decade, this had risen to 475 billion tonnes a year. This means that a third of all sea level rise is now caused by the loss of polar ice.

The most recent assessment by the IPCC is that, by 2100, sea levels will have risen by 53 cms, putting 360 million people who live at sea level at some risk.

“This would mean 400 million people at risk of annual coastal flooding by 2100”

But the latest finding from the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) scientists is that seas will rise even higher, and even more people will have to move.

“Every centimetre of sea level rise leads to coastal flooding and coastal erosion, disrupting people’s lives around the planet,” said Andrew Shepherd, professor of Earth observation at the University of Leeds, UK, as he and colleagues published their findings of Greenland losses in Nature journal.

“If Antarctica and Greenland continue to track the worst-case climate warning scenario, they will cause an extra 17 cms of sea level rise by the end of the century.

“This would mean 400 million people at risk of annual coastal flooding by 2100. These are not unlikely events with small impacts; they are already under way and will be devastating for coastal communities.”

Global picture

Professor Shepherd and his IMBIE colleagues established almost two years ago that Antarctica was losing ice at an ever-accelerating rate, but the Greenland survey completes the global picture.

And it remains a picture in which the Arctic seems to be warming at an accelerating rate and sea levels seem to be rising ever faster.

This is not just because the polar ice caps are melting, but also because, almost everywhere, mountain glaciers are in retreat, and the oceans are expanding as sea temperatures rise in response to the steady warming of the planetary atmosphere. – Climate News Network

Sandy beaches may succumb to rising seas

Ever higher seas are already eroding shorelines and flooding coasts. Soon the waves could wash away half the world’s sandy beaches.

LONDON, 5 March, 2020 – Right now, around a third of the world’s coastline is made up of sandy beaches and dunes which slope gently and softly to the sea. By the end of the century, these could make up only one-sixth of the frontier between land and ocean. Sea level rise driven by global heating could sweep half of them away.

Beaches are nature’s buffers between eroding land and tempestuous sea: they protect the coast, they provide a unique habitat for wildlife, and they have become powerful socio-economic resources.

But the paradise for surfers around sunlit Australia is almost certain to be diminished in the coming climate crisis as the waves lap ever higher, storm surges sweep away vast volumes of sand, and seas flood low-lying coasts. And – according to new European research in the journal Nature Climate Change – what is true for Australia is true for much of the rest of the world.

How much beach is lost will depend on how nations respond to the challenge of climate change. But in the worst-case scenario, Australia and Canada could each say goodbye to nearly 15,000 kilometres of sandy shore by 2100. Chile could lose more than 6,000 km, Mexico, China and the US more than 5,000 km, Russia more than 4,000 km and Argentina more than 3,000 km.

“Much of the world’s coast is already eroding, which could get worse with sea level rise”

And that’s the outlook for countries with vast coastlines. Some could fare even worse. Guinea-Bissau and The Gambia in West Africa, for instance, could lose 60% of their beaches.

The European scientists looked at more than 30 years of satellite data on coastal change – from 1984 to 2015 – and 82 years of climate and sea level predictions from a range of climate models. They also simulated 100 million storm events.

There is plenty of evidence that the world’s seas are responding to climate change; that sea levels are rising in response to warmer atmospheric temperatures driven by profligate combustion of fossil fuels; and that coastal flooding is likely to become more extreme.

But the detailed questions remain: how exactly will ever-higher tides exact their toll of the wetlands, mangrove forests, estuaries, cliff faces, rocky coasts, storm beaches and dunes that serve as a barrier between the maritime cities and towns of the world, and the saltwater? The researchers found that even in the more hopeful scenarios, there would be considerable losses.

UK backs study

But if nations delivered on the promise made in Paris in 2015 – a promise that still has to be backed up by urgent action on a global scale – to contain global heating to “well below” a maximum of 2°C by 2100, then perhaps 40% of the projected erosion of beaches could be halted.

Beaches are natural features of tidal landscapes: sand swept away by violent storms is eventually replaced by silt carried down the rivers to the coasts. The shoreline has always changed. But change is accelerating. Scientists in the UK have endorsed the European study.

“Much of the world’s coast is already eroding, which could get worse with sea level rise,” said Sally Brown, of Bournemouth University. Bournemouth is a famous British seaside resort.

“Building defences helps maintain coastline position, but defences are known to reduce beach width or depth over multiple decades. Responding to sea level rise means looking strategically at how and where we defend coasts today, which may mean protecting only limited parts of the coast.” – Climate News Network

Ever higher seas are already eroding shorelines and flooding coasts. Soon the waves could wash away half the world’s sandy beaches.

LONDON, 5 March, 2020 – Right now, around a third of the world’s coastline is made up of sandy beaches and dunes which slope gently and softly to the sea. By the end of the century, these could make up only one-sixth of the frontier between land and ocean. Sea level rise driven by global heating could sweep half of them away.

Beaches are nature’s buffers between eroding land and tempestuous sea: they protect the coast, they provide a unique habitat for wildlife, and they have become powerful socio-economic resources.

But the paradise for surfers around sunlit Australia is almost certain to be diminished in the coming climate crisis as the waves lap ever higher, storm surges sweep away vast volumes of sand, and seas flood low-lying coasts. And – according to new European research in the journal Nature Climate Change – what is true for Australia is true for much of the rest of the world.

How much beach is lost will depend on how nations respond to the challenge of climate change. But in the worst-case scenario, Australia and Canada could each say goodbye to nearly 15,000 kilometres of sandy shore by 2100. Chile could lose more than 6,000 km, Mexico, China and the US more than 5,000 km, Russia more than 4,000 km and Argentina more than 3,000 km.

“Much of the world’s coast is already eroding, which could get worse with sea level rise”

And that’s the outlook for countries with vast coastlines. Some could fare even worse. Guinea-Bissau and The Gambia in West Africa, for instance, could lose 60% of their beaches.

The European scientists looked at more than 30 years of satellite data on coastal change – from 1984 to 2015 – and 82 years of climate and sea level predictions from a range of climate models. They also simulated 100 million storm events.

There is plenty of evidence that the world’s seas are responding to climate change; that sea levels are rising in response to warmer atmospheric temperatures driven by profligate combustion of fossil fuels; and that coastal flooding is likely to become more extreme.

But the detailed questions remain: how exactly will ever-higher tides exact their toll of the wetlands, mangrove forests, estuaries, cliff faces, rocky coasts, storm beaches and dunes that serve as a barrier between the maritime cities and towns of the world, and the saltwater? The researchers found that even in the more hopeful scenarios, there would be considerable losses.

UK backs study

But if nations delivered on the promise made in Paris in 2015 – a promise that still has to be backed up by urgent action on a global scale – to contain global heating to “well below” a maximum of 2°C by 2100, then perhaps 40% of the projected erosion of beaches could be halted.

Beaches are natural features of tidal landscapes: sand swept away by violent storms is eventually replaced by silt carried down the rivers to the coasts. The shoreline has always changed. But change is accelerating. Scientists in the UK have endorsed the European study.

“Much of the world’s coast is already eroding, which could get worse with sea level rise,” said Sally Brown, of Bournemouth University. Bournemouth is a famous British seaside resort.

“Building defences helps maintain coastline position, but defences are known to reduce beach width or depth over multiple decades. Responding to sea level rise means looking strategically at how and where we defend coasts today, which may mean protecting only limited parts of the coast.” – Climate News Network

North Sea dams could save Europe’s coasts

There is a way to stop Europe’s coastal cities from vanishing below the waves – enclose the North Sea. But there’s a simpler solution.

LONDON, 4 March, 2020 − Two European scientists have proposed the ultimate flood barrier: they want to dam the North Sea and the English Channel with more than 600 kilometres (373 miles) of sea wall.

This would protect 15 nations in western Europe against the ravages of what could one day be 10 metres (33 feet) of sea level rise. It would ultimately turn the North Sea into a freshwater lake and, at up to €500 billion (£435 bn) or more, represent the single most costly piece of engineering ever.

But, the pair reason, to do nothing could cost the people of Europe perhaps 10 times as much as coasts eroded, the sea overwhelmed the Low Countries, reshaped the contours of a continent and forced 25 million people to move inland.

In their paper in the Bulletin of the American Meteorological SocietySjoerd Groeskamp of the Royal Netherlands Institute for Sea Research and Joakim Kjellsson of Geomar, the Helmholtz oceanographic research centre in Kiel, Germany, concede that what they propose “may seem an overwhelming and unrealistic solution at first.”

But compared with the cost of inaction, or the cost of managed retreat from the coastline that would displace millions, it could be the cheapest option. “It might be impossible to truly fathom the magnitude of the threat that global-mean sea level rise poses,” they warn.

Least bad option

Global average temperatures have risen by 1°C and sea levels by 21 cms (8 inches) since 1880. Sea level rise lags behind atmospheric warming, but the guess is that every degree Celsius in the air will be followed eventually by 2.3 metres (7.5 feet) of higher seas.

By 2100, temperatures could have risen more than 3°C and sea levels by up to 1.5 metres (5 feet). If nations carry on burning fossil fuels the icecaps will melt inexorably, and by 2500 seas could have risen by 10 metres.

“The best solution will always be the treatment of the cause: human-caused climate change,” they write. However, if nations do not act to control the greenhouse gas emissions and forest destruction that cause global heating, and ever higher tides, then solutions such as the North European Enclosure Dam, known for short as NEED, are the only option.

The two researchers propose a barrier, a dike of sloping sides 50 metres wide across the North Sea from Bergen in Norway to the north-east tip of Scotland, via the Shetland and Orkney Islands.

This would be 475 kms (295 miles) long, with an average depth of 127 metres (417 feet), but would have to cross a trench more than 300 metres (985 feet) deep. To withstand continued sea level rise beyond 2500, it would need to be 20 metres or more above the Atlantic waves.

“This dam is mainly a call to do something about climate change now. If we do nothing, then this extreme dam might just be the only solution”

The 160 kms (100 miles) of sea defence from south-west England to the westernmost point of France would be a little less problematic: sea depths are hardly more than 100 metres (330 feet).

But the engineers would also have to factor in the 40,000 cubic metres of river water that would discharge into this enclosed basin every second. This would mean the same volume would need pumping continuously into the Atlantic on the far side of the dikes.

Since the barrier would enclose a number of the world’s great shipping ports, there would have to be sluice gates to let the big ships through, or alternatively new ports on the ocean side of the barriers.

The very nature of the enclosed North Sea would begin to change. Within a decade or two, it would start to turn into a freshwater lake: it would be the end of centuries of a fishing industry.

It could – the scientists admit their calculations are of the “back of an envelope” variety – be done. They scaled up the costs of the world’s largest dikes so far in the Netherlands and South Korea, to calculate the 51 billion tonnes of sand needed for the project. This is about what the world uses every year in construction.

Technology tested

They note that fixed seabed oil platforms have been constructed to a depth of 500 metres (1,640 feet), so engineers already know how to do such things. Pumps of the scale required to handle the incoming river discharges are already in use, but they would be needed in their hundreds.

And although the cost would reach somewhere between €250-550 bn (£220-480 bn), this − spread over the 20 years the project would take − would represent only at most 0.32% of the gross domestic product of the UK, Netherlands, Germany, Belgium and Denmark combined: the five nations with most to lose from the rising tides.

It would, the authors argue, cost just the Netherlands – which already has 3,600 km (2,240 miles) of flood protection − a third of that sum to defend against sea level rises of only 1.5 metres. The good news is that, if such a project worked for western Europe, then the same techniques could enclose the Irish Sea, the Mediterranean, the Red Sea and the Persian Gulf.

“This dam makes it almost tangible what the consequences of continued sea level rise will be; a rise of 10 metres by the year 2500 according to the bleakest scenarios,” said Dr Groeskamp.

“This dam is therefore mainly a call to do something about climate change now. If we do nothing, then this extreme dam might just be the only solution.” − Climate News Network

There is a way to stop Europe’s coastal cities from vanishing below the waves – enclose the North Sea. But there’s a simpler solution.

LONDON, 4 March, 2020 − Two European scientists have proposed the ultimate flood barrier: they want to dam the North Sea and the English Channel with more than 600 kilometres (373 miles) of sea wall.

This would protect 15 nations in western Europe against the ravages of what could one day be 10 metres (33 feet) of sea level rise. It would ultimately turn the North Sea into a freshwater lake and, at up to €500 billion (£435 bn) or more, represent the single most costly piece of engineering ever.

But, the pair reason, to do nothing could cost the people of Europe perhaps 10 times as much as coasts eroded, the sea overwhelmed the Low Countries, reshaped the contours of a continent and forced 25 million people to move inland.

In their paper in the Bulletin of the American Meteorological SocietySjoerd Groeskamp of the Royal Netherlands Institute for Sea Research and Joakim Kjellsson of Geomar, the Helmholtz oceanographic research centre in Kiel, Germany, concede that what they propose “may seem an overwhelming and unrealistic solution at first.”

But compared with the cost of inaction, or the cost of managed retreat from the coastline that would displace millions, it could be the cheapest option. “It might be impossible to truly fathom the magnitude of the threat that global-mean sea level rise poses,” they warn.

Least bad option

Global average temperatures have risen by 1°C and sea levels by 21 cms (8 inches) since 1880. Sea level rise lags behind atmospheric warming, but the guess is that every degree Celsius in the air will be followed eventually by 2.3 metres (7.5 feet) of higher seas.

By 2100, temperatures could have risen more than 3°C and sea levels by up to 1.5 metres (5 feet). If nations carry on burning fossil fuels the icecaps will melt inexorably, and by 2500 seas could have risen by 10 metres.

“The best solution will always be the treatment of the cause: human-caused climate change,” they write. However, if nations do not act to control the greenhouse gas emissions and forest destruction that cause global heating, and ever higher tides, then solutions such as the North European Enclosure Dam, known for short as NEED, are the only option.

The two researchers propose a barrier, a dike of sloping sides 50 metres wide across the North Sea from Bergen in Norway to the north-east tip of Scotland, via the Shetland and Orkney Islands.

This would be 475 kms (295 miles) long, with an average depth of 127 metres (417 feet), but would have to cross a trench more than 300 metres (985 feet) deep. To withstand continued sea level rise beyond 2500, it would need to be 20 metres or more above the Atlantic waves.

“This dam is mainly a call to do something about climate change now. If we do nothing, then this extreme dam might just be the only solution”

The 160 kms (100 miles) of sea defence from south-west England to the westernmost point of France would be a little less problematic: sea depths are hardly more than 100 metres (330 feet).

But the engineers would also have to factor in the 40,000 cubic metres of river water that would discharge into this enclosed basin every second. This would mean the same volume would need pumping continuously into the Atlantic on the far side of the dikes.

Since the barrier would enclose a number of the world’s great shipping ports, there would have to be sluice gates to let the big ships through, or alternatively new ports on the ocean side of the barriers.

The very nature of the enclosed North Sea would begin to change. Within a decade or two, it would start to turn into a freshwater lake: it would be the end of centuries of a fishing industry.

It could – the scientists admit their calculations are of the “back of an envelope” variety – be done. They scaled up the costs of the world’s largest dikes so far in the Netherlands and South Korea, to calculate the 51 billion tonnes of sand needed for the project. This is about what the world uses every year in construction.

Technology tested

They note that fixed seabed oil platforms have been constructed to a depth of 500 metres (1,640 feet), so engineers already know how to do such things. Pumps of the scale required to handle the incoming river discharges are already in use, but they would be needed in their hundreds.

And although the cost would reach somewhere between €250-550 bn (£220-480 bn), this − spread over the 20 years the project would take − would represent only at most 0.32% of the gross domestic product of the UK, Netherlands, Germany, Belgium and Denmark combined: the five nations with most to lose from the rising tides.

It would, the authors argue, cost just the Netherlands – which already has 3,600 km (2,240 miles) of flood protection − a third of that sum to defend against sea level rises of only 1.5 metres. The good news is that, if such a project worked for western Europe, then the same techniques could enclose the Irish Sea, the Mediterranean, the Red Sea and the Persian Gulf.

“This dam makes it almost tangible what the consequences of continued sea level rise will be; a rise of 10 metres by the year 2500 according to the bleakest scenarios,” said Dr Groeskamp.

“This dam is therefore mainly a call to do something about climate change now. If we do nothing, then this extreme dam might just be the only solution.” − Climate News Network

Shrinking Arctic ice slows fish breeding rates

A food source for many species spawns under the Arctic ice. Now fish breeding problems, caused by ice melt, threaten its future.

LONDON, 3 March, 2020 − It’s relatively small, not particularly well-known, but it’s a key indicator of global warming, which is putting some fish breeding rates at risk: enter the polar cod (Boreogadus saida), the smaller cousin of the more familiar north-east Arctic cod.

A recent study by researchers at the Institute of Marine Research (IMR) in Norway has found that declines in winter sea ice cover in the Barents Sea region of the Arctic, plus warmer sea temperatures, are causing declines in polar cod reproduction rates.

This has grave implications − not just for future stocks of polar cod, but for the survival of many other Arctic species as well. The polar cod is a vital part of the Arctic food chain. After spawning under the ice in the early months of the year, the fish – feeding on a diet of zooplankton − grows quickly. It then becomes a food for other larger fish and for sea birds, seals and whales.

“Unfortunately, climate projections suggest that the Barents Sea will become warmer and virtually ice-free as early as in 2030”, says Mats Huserbråten, one of the study’s authors. “The outlook for this cornerstone of the Arctic food chain is therefore bad.”

End of breeding

If trends in ice reduction and the heating of Arctic waters continue, the reproductive cycle of the polar cod could collapse, say the researchers.

The fish is endemic to the polar regions (found nowhere else) and has developed in ways which make it dependent on the presence of ice. Its eggs are spawned under the ice, where they grow, even in sub-freezing temperatures. The larvae then feed on the zooplankton − plentiful in mid-year, when the annual ice melt occurs.

Winter ice cover in the Arctic has been in decline since the 1970s, with a sizeable part of the reduction happening in the Barents Sea.

The polar cod stock there has been monitored annually by a joint Norwegian-Russian survey since 1986. In the IMR study, researchers found that not only were stocks diminishing, but that what are described as spawning assemblages of the polar cod were moving further north.

“Climate projections suggest that the Barents Sea will become warmer and virtually ice-free as early as in 2030. The outlook for this cornerstone of the Arctic food chain is therefore bad”

As climate change warms the planet’s oceans, many fish species have been observed moving away from the equator in search of cooler waters. While such fish movements have resulted in bigger catches in some areas, fish stocks in many more southern regions are in sharp decline.

The reduction in winter ice cover in the Arctic caused by climate change is affecting a wide variety of species – from polar bears to the smallest marine life. It has also made the polar region more accessible – to cruise operators, shipping companies and to the fossil fuel industry.

The Norwegian study says growing human activity in the Arctic is putting further pressure on the polar cod and other vulnerable species.

“Together, these factors mean we need a better understanding of the possible impacts on Arctic ecosystems, to provide a basis for sustainable management of the high north”, say the researchers. “We have excellent tools at our disposal in the shape of models that can help us to understand trends and long-time series of survey data.” − Climate News Network

A food source for many species spawns under the Arctic ice. Now fish breeding problems, caused by ice melt, threaten its future.

LONDON, 3 March, 2020 − It’s relatively small, not particularly well-known, but it’s a key indicator of global warming, which is putting some fish breeding rates at risk: enter the polar cod (Boreogadus saida), the smaller cousin of the more familiar north-east Arctic cod.

A recent study by researchers at the Institute of Marine Research (IMR) in Norway has found that declines in winter sea ice cover in the Barents Sea region of the Arctic, plus warmer sea temperatures, are causing declines in polar cod reproduction rates.

This has grave implications − not just for future stocks of polar cod, but for the survival of many other Arctic species as well. The polar cod is a vital part of the Arctic food chain. After spawning under the ice in the early months of the year, the fish – feeding on a diet of zooplankton − grows quickly. It then becomes a food for other larger fish and for sea birds, seals and whales.

“Unfortunately, climate projections suggest that the Barents Sea will become warmer and virtually ice-free as early as in 2030”, says Mats Huserbråten, one of the study’s authors. “The outlook for this cornerstone of the Arctic food chain is therefore bad.”

End of breeding

If trends in ice reduction and the heating of Arctic waters continue, the reproductive cycle of the polar cod could collapse, say the researchers.

The fish is endemic to the polar regions (found nowhere else) and has developed in ways which make it dependent on the presence of ice. Its eggs are spawned under the ice, where they grow, even in sub-freezing temperatures. The larvae then feed on the zooplankton − plentiful in mid-year, when the annual ice melt occurs.

Winter ice cover in the Arctic has been in decline since the 1970s, with a sizeable part of the reduction happening in the Barents Sea.

The polar cod stock there has been monitored annually by a joint Norwegian-Russian survey since 1986. In the IMR study, researchers found that not only were stocks diminishing, but that what are described as spawning assemblages of the polar cod were moving further north.

“Climate projections suggest that the Barents Sea will become warmer and virtually ice-free as early as in 2030. The outlook for this cornerstone of the Arctic food chain is therefore bad”

As climate change warms the planet’s oceans, many fish species have been observed moving away from the equator in search of cooler waters. While such fish movements have resulted in bigger catches in some areas, fish stocks in many more southern regions are in sharp decline.

The reduction in winter ice cover in the Arctic caused by climate change is affecting a wide variety of species – from polar bears to the smallest marine life. It has also made the polar region more accessible – to cruise operators, shipping companies and to the fossil fuel industry.

The Norwegian study says growing human activity in the Arctic is putting further pressure on the polar cod and other vulnerable species.

“Together, these factors mean we need a better understanding of the possible impacts on Arctic ecosystems, to provide a basis for sustainable management of the high north”, say the researchers. “We have excellent tools at our disposal in the shape of models that can help us to understand trends and long-time series of survey data.” − Climate News Network

Hunger threat as tropical fish seek cooler waters

As climate heating drives tropical fish to seek survival elsewhere, humans will be left without the protein they need.

LONDON, 2 March, 2020 − Stocks of tropical fish that have provided vital protein for local people for generations may soon disappear as the oceans warm, leaving empty seas in their wake, scientists believe. But there could be help in international protection schemes.

Already researchers have found that fish are voting with their fins by diving deeper or migrating away from equatorial seas to find cooler waters. But now they have calculated, in a study published in the journal Nature, that tropical countries stand to lose most if not all of their fish stocks, with few if any species moving in to replace them.

Although scientists have known that the composition of stocks is changing in many world fisheries, they have not until now fully appreciated the devastating effect the climate crisis will have on tropical countries.

In the North Sea, for example, when fish like cod move north to find cooler and more congenial conditions for breeding, they are replaced by fish from further south which also have a commercial value, such as Mediterranean species like red mullet. But when fish move from the tropics there are no species from nearer the equator that are acclimatised to the hotter water and able to take their place.

Now Jorge García Molinos of Hokkaido University and colleagues in Japan and the US have undertaaken a comprehensive study of 779 commercial fish species to see how they would expand or contract their range under both moderate and more severe global warming between 2015 and 2100, using 2012 as a baseline for their distribution.

“The exit of many fishery stocks from these climate change-vulnerable nations is inevitable, but carefully designed international cooperation could significantly ease the impact on those nations”

The computer model they used showed that under moderate ocean warming tropical countries would lose 15% of their fish species by the end of this century. But if higher greenhouse gas emissions continued, fuelling more severe heat, that would rise to 40%.

The worst-affected countries would be along the north-west African seaboard, while south-east Asia, the Caribbean and Central America would also experience steep declines.

Alarmed by their findings, because of the effect they would have on the nutrition of the people who relied on fish protein for their survival, the scientists examined existing fisheries agreements to see if they took into account the fact that stocks might move because of climate change.

Analysis of 127 publicly-available international agreements showed that none contained language to deal with climate change or stock movements to other waters.

Some dealt with short-term stock fluctuations but not permanent movements, and did not deal with the possible over-fishing of replacement stocks.

Global help

The scientists suggest an urgent look at the issue at the annual UN climate talks because of the loss of fish stocks and the financial damage that warming seas will do to the economies of some of the world’s poorest countries.

They go further, suggesting that poor countries could apply for compensation for damage to their fisheries during negotiations under the Warsaw International Mechanism for Loss and Damage associated with Climate Change Impacts (WIM), and also raise the possibility of help from the Green Climate Fund, set up to help the poorest countries adapt to and mitigate the effects of climate change.

Professor García Molinos, based at Hokkaido’s Arctic Research Center,  said: “The exit of many fishery stocks from these climate-change vulnerable nations is inevitable, but carefully designed international cooperation together with the strictest enforcement of ambitious reductions of greenhouse gas emissions, especially by the highest-emitter countries, could significantly ease the impact on those nations.”

While the research relies on computer models to see how fish will react to warming seas in the future, the scientific evidence available shows that they are already responding. It also shows that keeping the world temperature increase down to 1.5°C, the preferred maximum agreed at the 2015 Paris climate talks, would help fisheries globally.

And the Hokkaido research demonstrates yet again how it is the poorest nations, which have contributed least to the carbon dioxide and other greenhouse gas emissions causing climate change, that will suffer most from their effects. − Climate News Network

As climate heating drives tropical fish to seek survival elsewhere, humans will be left without the protein they need.

LONDON, 2 March, 2020 − Stocks of tropical fish that have provided vital protein for local people for generations may soon disappear as the oceans warm, leaving empty seas in their wake, scientists believe. But there could be help in international protection schemes.

Already researchers have found that fish are voting with their fins by diving deeper or migrating away from equatorial seas to find cooler waters. But now they have calculated, in a study published in the journal Nature, that tropical countries stand to lose most if not all of their fish stocks, with few if any species moving in to replace them.

Although scientists have known that the composition of stocks is changing in many world fisheries, they have not until now fully appreciated the devastating effect the climate crisis will have on tropical countries.

In the North Sea, for example, when fish like cod move north to find cooler and more congenial conditions for breeding, they are replaced by fish from further south which also have a commercial value, such as Mediterranean species like red mullet. But when fish move from the tropics there are no species from nearer the equator that are acclimatised to the hotter water and able to take their place.

Now Jorge García Molinos of Hokkaido University and colleagues in Japan and the US have undertaaken a comprehensive study of 779 commercial fish species to see how they would expand or contract their range under both moderate and more severe global warming between 2015 and 2100, using 2012 as a baseline for their distribution.

“The exit of many fishery stocks from these climate change-vulnerable nations is inevitable, but carefully designed international cooperation could significantly ease the impact on those nations”

The computer model they used showed that under moderate ocean warming tropical countries would lose 15% of their fish species by the end of this century. But if higher greenhouse gas emissions continued, fuelling more severe heat, that would rise to 40%.

The worst-affected countries would be along the north-west African seaboard, while south-east Asia, the Caribbean and Central America would also experience steep declines.

Alarmed by their findings, because of the effect they would have on the nutrition of the people who relied on fish protein for their survival, the scientists examined existing fisheries agreements to see if they took into account the fact that stocks might move because of climate change.

Analysis of 127 publicly-available international agreements showed that none contained language to deal with climate change or stock movements to other waters.

Some dealt with short-term stock fluctuations but not permanent movements, and did not deal with the possible over-fishing of replacement stocks.

Global help

The scientists suggest an urgent look at the issue at the annual UN climate talks because of the loss of fish stocks and the financial damage that warming seas will do to the economies of some of the world’s poorest countries.

They go further, suggesting that poor countries could apply for compensation for damage to their fisheries during negotiations under the Warsaw International Mechanism for Loss and Damage associated with Climate Change Impacts (WIM), and also raise the possibility of help from the Green Climate Fund, set up to help the poorest countries adapt to and mitigate the effects of climate change.

Professor García Molinos, based at Hokkaido’s Arctic Research Center,  said: “The exit of many fishery stocks from these climate-change vulnerable nations is inevitable, but carefully designed international cooperation together with the strictest enforcement of ambitious reductions of greenhouse gas emissions, especially by the highest-emitter countries, could significantly ease the impact on those nations.”

While the research relies on computer models to see how fish will react to warming seas in the future, the scientific evidence available shows that they are already responding. It also shows that keeping the world temperature increase down to 1.5°C, the preferred maximum agreed at the 2015 Paris climate talks, would help fisheries globally.

And the Hokkaido research demonstrates yet again how it is the poorest nations, which have contributed least to the carbon dioxide and other greenhouse gas emissions causing climate change, that will suffer most from their effects. − Climate News Network

Rising tides will leave no choice for US millions

Time and tide wait for no-one. As sea levels rise, the rising tides will become more impatient. Millions of Americans will have to migrate.

LONDON, 26 February, 2020 – The Texan city of Houston is about to grow in unexpected ways, thanks to the rising tides. So will Dallas. Real estate agents in Atlanta, Georgia; Denver, Colorado; and Las Vegas, Nevada could expect to do roaring business.

The inland counties around Los Angeles, and close to New Orleans in Louisiana, will suddenly get a little more crowded. And from Boston in the north-east to the tip of Florida, Americans will be on the move.

That is because an estimated 13 million US citizens could some time in this century become climate refugees, driven from their seaside homes by sea level rise of possibly 1.8 metres, according to new research.

And they will have to move home in a poorer economic climate: worldwide. If governments and city authorities do not take the right steps, sea level rise could erode 4% of the global annual economy, says a separate study. That is, coast-dwellers could witness not just their towns and even cities washed away: they could see their prosperity go under as well.

Californian scientists report in the Public Library of Science journal PLOS One that they used machine learning techniques – in effect, artificial intelligence systems – to calculate what is most likely to happen as US citizens desert Delaware Bay, slip away from the cities of North and South Carolina, and flee Florida in the face of rising sea levels, coastal flooding and increasingly catastrophic windstorms.

“Sea level rise will affect every county in the United States … everybody should care about sea level rise, whether they live on the coast or not”

In the year 2000, a third of all the planet’s urban land was in a zone vulnerable to flood. By 2040, this could rise to 40%. In 2010, in the US, more than 120m citizens – that is nearly 40% of the entire population – lived in coastal counties. By 2020, this proportion could already be higher.

And by 2100, at least 13.1m people could be living on land likely to be inundated if sea levels rise by 1.8 metres. Except that they won’t: they will have already seen the future and moved away from it, to some settlement well away from the rising tides.

Those who might otherwise have purchased their abandoned seaside houses will be looking for somewhere safer and adding to the pressure on the housing market.

“Sea level rise will affect every county in the United States,” said Bistra Dilkina of the University of Southern California at Irvine, a computer scientist who worked with engineers to model the human response to the future.

She and her colleagues started from patterns of movement that began with Hurricane Katrina, in 2004, and Hurricane Rita a year later, both in Louisiana. They then let the algorithms take over the challenge of guessing what American families and businesses are most likely to do as the tides begin to flood the high streets.

Action promised

“We hope this research will empower urban planners and local decision-makers to prepare to accept populations displaced by sea level rise. Our findings indicate that everybody should care about sea level rise, whether they live on the coast or not,” she said.

The California team’s worst-case forecasts are based on a premise that the world takes no real action to combat sea level rise, which is driven by global warming powered in turn by fossil fuel emissions into the atmosphere on an ever-increasing scale.

But in Paris in 2015, more than 190 nations did agree to act: to contain global warming to “well below” 2°C by the century’s end. So far, very few have committed to sufficient action, and the President of the US has pronounced climate change a “hoax” and announced a withdrawal from the Paris Agreement.

Researchers in Austria report in the journal Environmental Research Communications that they decided to consider the potential economic cost worldwide of sea level rise alone. Scientists have been trying for years to guess the cost of flood damage to come: the latest study is of the impact of sea level rise and coastal flooding upon national economies worldwide.

The scientists considered two scenarios, including one in which the world kept the promises made in Paris, and one in which it did not, and made no attempt to adapt to or mitigate climate change.

Significant impact

By 2050 losses in each scenario would be significant and much the same. But by 2100, the do-nothing option promised to hit the gross domestic product – an economist’s favourite measure of economic well-being – by 4%.

Europe and Japan would be significantly hit; China , India and Canada hardest of all. If the world’s richest nations actually worked to limit climate change and adapt to the challenges ahead, the impact on the economy could be limited to 1%.

“The findings of this paper demonstrate that we need to think long term while acting swiftly,” said Thomas Schinko of the International Institute for Applied Systems Analysis in Austria, who led the study.

“Macroeconomic impacts up to and beyond 2050 as a result of coastal flooding due to sea level rise – not taking into account any other climate-related impacts such as drought – are severe and increasing.

“We, as a global society, need to further co-ordinate mitigation, adaptation and climate-resilient development and consider where we build cities and situate important infrastructure.” – Climate News Network

Time and tide wait for no-one. As sea levels rise, the rising tides will become more impatient. Millions of Americans will have to migrate.

LONDON, 26 February, 2020 – The Texan city of Houston is about to grow in unexpected ways, thanks to the rising tides. So will Dallas. Real estate agents in Atlanta, Georgia; Denver, Colorado; and Las Vegas, Nevada could expect to do roaring business.

The inland counties around Los Angeles, and close to New Orleans in Louisiana, will suddenly get a little more crowded. And from Boston in the north-east to the tip of Florida, Americans will be on the move.

That is because an estimated 13 million US citizens could some time in this century become climate refugees, driven from their seaside homes by sea level rise of possibly 1.8 metres, according to new research.

And they will have to move home in a poorer economic climate: worldwide. If governments and city authorities do not take the right steps, sea level rise could erode 4% of the global annual economy, says a separate study. That is, coast-dwellers could witness not just their towns and even cities washed away: they could see their prosperity go under as well.

Californian scientists report in the Public Library of Science journal PLOS One that they used machine learning techniques – in effect, artificial intelligence systems – to calculate what is most likely to happen as US citizens desert Delaware Bay, slip away from the cities of North and South Carolina, and flee Florida in the face of rising sea levels, coastal flooding and increasingly catastrophic windstorms.

“Sea level rise will affect every county in the United States … everybody should care about sea level rise, whether they live on the coast or not”

In the year 2000, a third of all the planet’s urban land was in a zone vulnerable to flood. By 2040, this could rise to 40%. In 2010, in the US, more than 120m citizens – that is nearly 40% of the entire population – lived in coastal counties. By 2020, this proportion could already be higher.

And by 2100, at least 13.1m people could be living on land likely to be inundated if sea levels rise by 1.8 metres. Except that they won’t: they will have already seen the future and moved away from it, to some settlement well away from the rising tides.

Those who might otherwise have purchased their abandoned seaside houses will be looking for somewhere safer and adding to the pressure on the housing market.

“Sea level rise will affect every county in the United States,” said Bistra Dilkina of the University of Southern California at Irvine, a computer scientist who worked with engineers to model the human response to the future.

She and her colleagues started from patterns of movement that began with Hurricane Katrina, in 2004, and Hurricane Rita a year later, both in Louisiana. They then let the algorithms take over the challenge of guessing what American families and businesses are most likely to do as the tides begin to flood the high streets.

Action promised

“We hope this research will empower urban planners and local decision-makers to prepare to accept populations displaced by sea level rise. Our findings indicate that everybody should care about sea level rise, whether they live on the coast or not,” she said.

The California team’s worst-case forecasts are based on a premise that the world takes no real action to combat sea level rise, which is driven by global warming powered in turn by fossil fuel emissions into the atmosphere on an ever-increasing scale.

But in Paris in 2015, more than 190 nations did agree to act: to contain global warming to “well below” 2°C by the century’s end. So far, very few have committed to sufficient action, and the President of the US has pronounced climate change a “hoax” and announced a withdrawal from the Paris Agreement.

Researchers in Austria report in the journal Environmental Research Communications that they decided to consider the potential economic cost worldwide of sea level rise alone. Scientists have been trying for years to guess the cost of flood damage to come: the latest study is of the impact of sea level rise and coastal flooding upon national economies worldwide.

The scientists considered two scenarios, including one in which the world kept the promises made in Paris, and one in which it did not, and made no attempt to adapt to or mitigate climate change.

Significant impact

By 2050 losses in each scenario would be significant and much the same. But by 2100, the do-nothing option promised to hit the gross domestic product – an economist’s favourite measure of economic well-being – by 4%.

Europe and Japan would be significantly hit; China , India and Canada hardest of all. If the world’s richest nations actually worked to limit climate change and adapt to the challenges ahead, the impact on the economy could be limited to 1%.

“The findings of this paper demonstrate that we need to think long term while acting swiftly,” said Thomas Schinko of the International Institute for Applied Systems Analysis in Austria, who led the study.

“Macroeconomic impacts up to and beyond 2050 as a result of coastal flooding due to sea level rise – not taking into account any other climate-related impacts such as drought – are severe and increasing.

“We, as a global society, need to further co-ordinate mitigation, adaptation and climate-resilient development and consider where we build cities and situate important infrastructure.” – Climate News Network

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

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