Tag Archives: Warming

Hot future prompts new ideas for cool cities

Higher temperatures must mean more energy just to cool cities – which means even more heat. But ingenuity is already proposing answers.

LONDON, 15 August, 2019 − The world could need a quarter more energy by 2050, to cool cities and survive the global heating expected by then. And that assumes that nations will have taken steps to control greenhouse gas emissions and that the rise in temperature will be moderate.

If, on the other hand, the world goes on burning fossil fuels under the notorious “business as usual” scenario, then according to new research the people of the planet could demand up to 58% more energy, just to drive the extra air conditioning and refrigeration in ever more frequent and ever more intense extremes of heat.

The latest study, by researchers based in Boston, Massachusetts and Venice in Italy, helps to settle one of the more intricate questions that accompany climate projections and energy demand: yes, there will be more people and bigger cities which demand more power anyway, and yes, warm zones will get hotter and demand more expense on keeping cool. But chilly and temperate nations will enjoy milder winters and spend less on staying warm. Which wins?

The new paper, in the journal Nature Communications, either settles the matter or provides fellow scientists with a methodology and a set of results to examine more closely.

Risky faster heating

A warmer world will also be vastly more energy-expensive. And if nations invest in coal, oil or natural gas to provide the extra electricity to provide the air-conditioning, drive the electric fans and refrigerate food and medical supplies, then global heating would accelerate to ever more dangerous levels.

“At this point, we don’t know. To cool my house, I could buy a bigger air-conditioner. Or if higher demand makes electricity more expensive, I could choose to open my window or run a fan,” said Ian Sue Wing, an earth and environment scientist at Boston University, who led the study.

“We could use coal or we could use renewable sources, and those two choices mean very different things for our future. With coal, it will mean more greenhouse gas emissions. That’s what keeps me up at night.”

By 2050, there could be between 8.4bn and 10bn people on the planet. Gross domestic product per person (an economist’s measure of income and spending) could have all but doubled or even in some places more than trebled. Tropical and mid-latitude zones could, if warming is only moderate, experience as many as an extra 50 uncomfortably hot days each year. If the warming is vigorous, the number could soar to 75.

“We could use coal or we could use renewable sources. With coal, it will mean more greenhouse gas emissions. That’s what keeps me up at night”

Researchers have warned, consistently and repeatedly, that even a modest rise in average planetary temperatures will take the form of longer and more intense heat waves. By 2100 three out of four people on the planet could be exposed to heat extremes, and those most at hazard will be living in the tropical and subtropical megacities.

Extremes of heat can kill – one group has already identified 27 ways in which to die of rising temperatures – and scientists began warning years ago that ever more needed investment in air-conditioning equipment would only make energy demand, and perhaps greenhouse gas emissions, worse, while also contributing to ever greater outdoor temperatures.

So researchers have been looking at other approaches. The puzzle has already tested the levels of ingenuity and fresh thinking in the world’s energy laboratories. Researchers have cheerfully proposed reflector roofs that could send 97% of the sunlight back into space.

They have explored nature’s answer to the unforgiving sun: more trees in cities could take temperatures down by as much as 5°C and even make cities wealthier and healthier. And already this month, scientists and engineers have suggested two new ways to address the challenge of the overheating cities.

One US team at the University of Buffalo, working with the King Abdullah University in Saudi Arabia, has devised an inexpensive polymer-aluminium film that keeps itself cool, packed in a specially designed solar shelter. The film absorbs heat from the air and converts it to thermal radiation that can be beamed back into space.

Deep cuts possible

The researchers report, in the journal Nature Sustainability, that in the laboratory temperatures could be lowered by up to 11°C. On a clear, sunny day in New York state, they achieved outdoor all-day temperature reductions of 2°C to 9°C.

This exercise in entirely passive cooling – no electricity, just rooftop boxes – is in its infancy. But there are other approaches to the “heat island effect” that already makes modern cities uncomfortable.

Researchers at the University of Rutgers in the US simply looked at the ground beneath their feet. Pavement and road surfaces made of concrete or asphalt cover 30% of most cities and in high summer these surfaces can reach 60°C.

So, the Rutgers engineers report in the Journal of Cleaner Production,  roads could be made of permeable concrete, through which water could drain. It might give off more heat on sunny days, but after rainfall the water could run through, and evaporate through the pores, to reduce pavement heat by up to 30%.

And in addition, their concrete treated with fly ash and steel slag would make a huge difference to stormwater management and reduce the risk of urban flash floods. − Climate News Network

Higher temperatures must mean more energy just to cool cities – which means even more heat. But ingenuity is already proposing answers.

LONDON, 15 August, 2019 − The world could need a quarter more energy by 2050, to cool cities and survive the global heating expected by then. And that assumes that nations will have taken steps to control greenhouse gas emissions and that the rise in temperature will be moderate.

If, on the other hand, the world goes on burning fossil fuels under the notorious “business as usual” scenario, then according to new research the people of the planet could demand up to 58% more energy, just to drive the extra air conditioning and refrigeration in ever more frequent and ever more intense extremes of heat.

The latest study, by researchers based in Boston, Massachusetts and Venice in Italy, helps to settle one of the more intricate questions that accompany climate projections and energy demand: yes, there will be more people and bigger cities which demand more power anyway, and yes, warm zones will get hotter and demand more expense on keeping cool. But chilly and temperate nations will enjoy milder winters and spend less on staying warm. Which wins?

The new paper, in the journal Nature Communications, either settles the matter or provides fellow scientists with a methodology and a set of results to examine more closely.

Risky faster heating

A warmer world will also be vastly more energy-expensive. And if nations invest in coal, oil or natural gas to provide the extra electricity to provide the air-conditioning, drive the electric fans and refrigerate food and medical supplies, then global heating would accelerate to ever more dangerous levels.

“At this point, we don’t know. To cool my house, I could buy a bigger air-conditioner. Or if higher demand makes electricity more expensive, I could choose to open my window or run a fan,” said Ian Sue Wing, an earth and environment scientist at Boston University, who led the study.

“We could use coal or we could use renewable sources, and those two choices mean very different things for our future. With coal, it will mean more greenhouse gas emissions. That’s what keeps me up at night.”

By 2050, there could be between 8.4bn and 10bn people on the planet. Gross domestic product per person (an economist’s measure of income and spending) could have all but doubled or even in some places more than trebled. Tropical and mid-latitude zones could, if warming is only moderate, experience as many as an extra 50 uncomfortably hot days each year. If the warming is vigorous, the number could soar to 75.

“We could use coal or we could use renewable sources. With coal, it will mean more greenhouse gas emissions. That’s what keeps me up at night”

Researchers have warned, consistently and repeatedly, that even a modest rise in average planetary temperatures will take the form of longer and more intense heat waves. By 2100 three out of four people on the planet could be exposed to heat extremes, and those most at hazard will be living in the tropical and subtropical megacities.

Extremes of heat can kill – one group has already identified 27 ways in which to die of rising temperatures – and scientists began warning years ago that ever more needed investment in air-conditioning equipment would only make energy demand, and perhaps greenhouse gas emissions, worse, while also contributing to ever greater outdoor temperatures.

So researchers have been looking at other approaches. The puzzle has already tested the levels of ingenuity and fresh thinking in the world’s energy laboratories. Researchers have cheerfully proposed reflector roofs that could send 97% of the sunlight back into space.

They have explored nature’s answer to the unforgiving sun: more trees in cities could take temperatures down by as much as 5°C and even make cities wealthier and healthier. And already this month, scientists and engineers have suggested two new ways to address the challenge of the overheating cities.

One US team at the University of Buffalo, working with the King Abdullah University in Saudi Arabia, has devised an inexpensive polymer-aluminium film that keeps itself cool, packed in a specially designed solar shelter. The film absorbs heat from the air and converts it to thermal radiation that can be beamed back into space.

Deep cuts possible

The researchers report, in the journal Nature Sustainability, that in the laboratory temperatures could be lowered by up to 11°C. On a clear, sunny day in New York state, they achieved outdoor all-day temperature reductions of 2°C to 9°C.

This exercise in entirely passive cooling – no electricity, just rooftop boxes – is in its infancy. But there are other approaches to the “heat island effect” that already makes modern cities uncomfortable.

Researchers at the University of Rutgers in the US simply looked at the ground beneath their feet. Pavement and road surfaces made of concrete or asphalt cover 30% of most cities and in high summer these surfaces can reach 60°C.

So, the Rutgers engineers report in the Journal of Cleaner Production,  roads could be made of permeable concrete, through which water could drain. It might give off more heat on sunny days, but after rainfall the water could run through, and evaporate through the pores, to reduce pavement heat by up to 30%.

And in addition, their concrete treated with fly ash and steel slag would make a huge difference to stormwater management and reduce the risk of urban flash floods. − Climate News Network

Humans cause Antarctic ice melt, study finds

Yes, it’s us. Human activities are to blame for at least part of what’s melting the West Antarctic Ice Sheet, scientists say.

LONDON, 13 August, 2019 − A team of British and American scientists has found what it says is unequivocal evidence that humans are responsible for significant Antarctic ice melt.

They say their study provides the first evidence of a direct link between global warming from human activities and the melting of the West Antarctic Ice Sheet (WAIS).

The discovery is fundamentally important to international efforts to limit climate change, as a small number of scientists still argue that global warming results from natural rather than human causes. That argument should from now on be harder to sustain.

Ice loss in West Antarctica has increased substantially in the last few decades, and is continuing. Scientists have known for some time that the loss is caused by melting driven from the ocean, and that varying winds in the region cause transitions between relatively warm and cool ocean conditions around key glaciers. But until now it was unclear how these naturally-occurring wind variations could cause the ice loss.

“We knew this region was affected by natural climate cycles. Now we have evidence that a century-long change underlies these cycles, and that it is caused by human activities”

The UK-US team report in the journal Nature Geoscience that, as well as the natural wind variations, which last about a decade, there has been a much longer-term change in the winds that can be linked with human activities.

This result is important for another reason as well: continued ice loss from the WAIS could cause tens of centimetres of sea level rise by the year 2100.

The researchers combined satellite observations and climate model simulations to understand how winds over the ocean near West Antarctica have changed since the 1920s in response to rising greenhouse gas concentrations.

Their investigation shows that human-induced climate change has caused the longer-term change in the winds, and that warm ocean conditions have gradually become more prevalent as a result.

The team’s members are from the British Antarctic Survey (BAS), Columbia University’s Lamont-Doherty Earth Observatory in New York, and the University of Washington.

Galloping speed-up

BAS is one of the organisations researching a huge West Antarctic ice mass in the International Thwaites Glacier Collaboration, aimed at finding out how soon it and its neighbour, the Pine Island glacier, may collapse, with implications for sea levels worldwide.

The fact that melting at both poles has been accelerating fast has been known for some time, though not the reason. Since 1979 Antarctica’s ice loss has grown six times faster, and Greenland’s four times since the turn of the century.

One British scientist, Professor Martin Siegert, has said what is happening in the Antarctic means the world “will be locked into substantial global changes” unless it alters course radically by 2030.

The lead author of the new study, Paul Holland from BAS, said the impact of human-induced climate change on the WAIS was not simple: “Our results imply that a combination of human activity and natural climate variations have caused ice loss in this region, accounting for around 4.5 cm of sea level rise per century.”

Act now

The team also looked at model simulations of future winds. Professor Holland added: “An important finding is that if high greenhouse gas emissions continue in future, the winds keep changing and there could be a further increase in ice melting.

“However, if emissions of greenhouse gases are curtailed, there is little change in the winds from present-day conditions. This shows that curbing greenhouse gas emissions now could reduce the future sea level contribution from this region.”

One co-author, Professor Pierre Dutrieux from Lamont-Doherty Earth Observatory, said: “We knew this region was affected by natural climate cycles lasting about a decade, but these didn’t necessarily explain the ice loss. Now we have evidence that a century-long change underlies these cycles, and that it is caused by human activities.”

Another co-author, Professor Eric Steig from the University of Washington, said: “These results solve a long-standing puzzle.  We have known for some time that varying winds near the West Antarctic Ice Sheet have contributed to the ice loss, but it has not been clear why the ice sheet is changing now.

“Our work with ice cores drilled in the Antarctic Ice Sheet have shown, for example, that wind conditions have been similar in the past. But the ice core data also suggest a subtle long-term trend in the winds. This new work corroborates that evidence and, furthermore, explains why that trend has occurred.” − Climate News Network

Yes, it’s us. Human activities are to blame for at least part of what’s melting the West Antarctic Ice Sheet, scientists say.

LONDON, 13 August, 2019 − A team of British and American scientists has found what it says is unequivocal evidence that humans are responsible for significant Antarctic ice melt.

They say their study provides the first evidence of a direct link between global warming from human activities and the melting of the West Antarctic Ice Sheet (WAIS).

The discovery is fundamentally important to international efforts to limit climate change, as a small number of scientists still argue that global warming results from natural rather than human causes. That argument should from now on be harder to sustain.

Ice loss in West Antarctica has increased substantially in the last few decades, and is continuing. Scientists have known for some time that the loss is caused by melting driven from the ocean, and that varying winds in the region cause transitions between relatively warm and cool ocean conditions around key glaciers. But until now it was unclear how these naturally-occurring wind variations could cause the ice loss.

“We knew this region was affected by natural climate cycles. Now we have evidence that a century-long change underlies these cycles, and that it is caused by human activities”

The UK-US team report in the journal Nature Geoscience that, as well as the natural wind variations, which last about a decade, there has been a much longer-term change in the winds that can be linked with human activities.

This result is important for another reason as well: continued ice loss from the WAIS could cause tens of centimetres of sea level rise by the year 2100.

The researchers combined satellite observations and climate model simulations to understand how winds over the ocean near West Antarctica have changed since the 1920s in response to rising greenhouse gas concentrations.

Their investigation shows that human-induced climate change has caused the longer-term change in the winds, and that warm ocean conditions have gradually become more prevalent as a result.

The team’s members are from the British Antarctic Survey (BAS), Columbia University’s Lamont-Doherty Earth Observatory in New York, and the University of Washington.

Galloping speed-up

BAS is one of the organisations researching a huge West Antarctic ice mass in the International Thwaites Glacier Collaboration, aimed at finding out how soon it and its neighbour, the Pine Island glacier, may collapse, with implications for sea levels worldwide.

The fact that melting at both poles has been accelerating fast has been known for some time, though not the reason. Since 1979 Antarctica’s ice loss has grown six times faster, and Greenland’s four times since the turn of the century.

One British scientist, Professor Martin Siegert, has said what is happening in the Antarctic means the world “will be locked into substantial global changes” unless it alters course radically by 2030.

The lead author of the new study, Paul Holland from BAS, said the impact of human-induced climate change on the WAIS was not simple: “Our results imply that a combination of human activity and natural climate variations have caused ice loss in this region, accounting for around 4.5 cm of sea level rise per century.”

Act now

The team also looked at model simulations of future winds. Professor Holland added: “An important finding is that if high greenhouse gas emissions continue in future, the winds keep changing and there could be a further increase in ice melting.

“However, if emissions of greenhouse gases are curtailed, there is little change in the winds from present-day conditions. This shows that curbing greenhouse gas emissions now could reduce the future sea level contribution from this region.”

One co-author, Professor Pierre Dutrieux from Lamont-Doherty Earth Observatory, said: “We knew this region was affected by natural climate cycles lasting about a decade, but these didn’t necessarily explain the ice loss. Now we have evidence that a century-long change underlies these cycles, and that it is caused by human activities.”

Another co-author, Professor Eric Steig from the University of Washington, said: “These results solve a long-standing puzzle.  We have known for some time that varying winds near the West Antarctic Ice Sheet have contributed to the ice loss, but it has not been clear why the ice sheet is changing now.

“Our work with ice cores drilled in the Antarctic Ice Sheet have shown, for example, that wind conditions have been similar in the past. But the ice core data also suggest a subtle long-term trend in the winds. This new work corroborates that evidence and, furthermore, explains why that trend has occurred.” − Climate News Network

Ocean heat waves damage reefs and kill coral

Heat extremes on land can kill. Ocean heat waves can devastate coral reefs and other ecosystems – and these too are on the increase.

LONDON, 12 August, 2019 − Heat extremes on the high seas are on the increase, with ocean heat waves disturbing ecosystems in two hemispheres and two great oceans, US scientists report.

And these same sudden rises in sea temperatures don’t just damage coral reefs, they kill the corals and start the process of reef decay, according to a separate study by Australian researchers.

Andrew Pershing of the Gulf of Maine Research Institute and colleagues report in the Proceedings of the National Academy of Sciences that they examined data from 65 marine ecosystems over the years 1854 to 2018 to work out how frequently ocean temperatures suddenly rose to unexpected levels.

They found such deviations from the average in the Arctic, North Atlantic, eastern Pacific and off the Australian coasts. They expected to find evidence of occasional hot flushes. But they did not expect to find quite so many.

“Severe marine heatwave events can have a far more severe impact than coral bleaching – the animal dies and its underlying skeleton is all that remains”

“Across the 65 ecosystems we examined, we expected about six or seven of them would experience these ‘surprises’ each year,” Dr Pershing said. “Instead, we’ve seen an average of 12 ecosystems experiencing these warming events each year over the past seven years, including a high of 23 ‘surprises’ in 2016.”

Intense and sudden changes in sea temperatures affect crustaceans, algae, corals, molluscs and many millions of humans who depend on the oceans for income. And a new study by researchers from Australian universities reports that even a rise of 0.5°C is reflected in deaths during an outbreak of coral bleaching.

Corals live in symbiosis with algae: ocean warming periodically disturbs this normally beneficial relationship. The coral animals evert (turn out) the algae and once-lurid reefs will bleach, and become more vulnerable to disease.

Corals support the world’s richest ocean ecosystems so such changes are a challenge, both to the survival of biodiversity and to local incomes from the tourism linked to the beauty of the reefs.

Very warm water

“What we are seeing is that severe marine heatwave events can have a far more severe impact than coral bleaching: the water temperatures are so warm that that the coral animal doesn’t bleach – in terms of a loss of its symbiosis – the animal dies and its underlying skeleton is all that remains,” said Tracy Ainsworth of the University of New South Wales.

The researchers report in the journal Current Biology that they used computer tomography scanning techniques to explore the marine destruction. In 2016, more than 30% of the northern part of Australia’s Great Barrier Reef experienced temperatures higher than those in which corals can survive.

“We find that the skeleton is immediately overgrown by rapid growth of algae and bacteria,” said Bill Leggat of the University of Newcastle, a co-author.

“We show that this process is devastating not just for the animal tissue but also for the skeleton that is left behind, which is rapidly eroded and weakened.” − Climate News Network

Heat extremes on land can kill. Ocean heat waves can devastate coral reefs and other ecosystems – and these too are on the increase.

LONDON, 12 August, 2019 − Heat extremes on the high seas are on the increase, with ocean heat waves disturbing ecosystems in two hemispheres and two great oceans, US scientists report.

And these same sudden rises in sea temperatures don’t just damage coral reefs, they kill the corals and start the process of reef decay, according to a separate study by Australian researchers.

Andrew Pershing of the Gulf of Maine Research Institute and colleagues report in the Proceedings of the National Academy of Sciences that they examined data from 65 marine ecosystems over the years 1854 to 2018 to work out how frequently ocean temperatures suddenly rose to unexpected levels.

They found such deviations from the average in the Arctic, North Atlantic, eastern Pacific and off the Australian coasts. They expected to find evidence of occasional hot flushes. But they did not expect to find quite so many.

“Severe marine heatwave events can have a far more severe impact than coral bleaching – the animal dies and its underlying skeleton is all that remains”

“Across the 65 ecosystems we examined, we expected about six or seven of them would experience these ‘surprises’ each year,” Dr Pershing said. “Instead, we’ve seen an average of 12 ecosystems experiencing these warming events each year over the past seven years, including a high of 23 ‘surprises’ in 2016.”

Intense and sudden changes in sea temperatures affect crustaceans, algae, corals, molluscs and many millions of humans who depend on the oceans for income. And a new study by researchers from Australian universities reports that even a rise of 0.5°C is reflected in deaths during an outbreak of coral bleaching.

Corals live in symbiosis with algae: ocean warming periodically disturbs this normally beneficial relationship. The coral animals evert (turn out) the algae and once-lurid reefs will bleach, and become more vulnerable to disease.

Corals support the world’s richest ocean ecosystems so such changes are a challenge, both to the survival of biodiversity and to local incomes from the tourism linked to the beauty of the reefs.

Very warm water

“What we are seeing is that severe marine heatwave events can have a far more severe impact than coral bleaching: the water temperatures are so warm that that the coral animal doesn’t bleach – in terms of a loss of its symbiosis – the animal dies and its underlying skeleton is all that remains,” said Tracy Ainsworth of the University of New South Wales.

The researchers report in the journal Current Biology that they used computer tomography scanning techniques to explore the marine destruction. In 2016, more than 30% of the northern part of Australia’s Great Barrier Reef experienced temperatures higher than those in which corals can survive.

“We find that the skeleton is immediately overgrown by rapid growth of algae and bacteria,” said Bill Leggat of the University of Newcastle, a co-author.

“We show that this process is devastating not just for the animal tissue but also for the skeleton that is left behind, which is rapidly eroded and weakened.” − Climate News Network

Artificial snow could save world’s coasts

In theory, artificial snow could save the ice caps and limit sea level rise. But rescuing civilisation this way would sacrifice Antarctica.

LONDON, 2 August, 2019 − German scientists have proposed a startling new way of slowing sea level rise and saving New York, Shanghai, Amsterdam and Miami from 3.3 metres of ocean flooding − by using artificial snow.

They suggest the rising seas could be halted by turning West Antarctica, one of the last undisturbed places on Earth, into an industrial snow complex, complete with a sophisticated distribution system.

An estimated 12,000 high-performance wind turbines could be used to generate the 145 Gigawatts of power (one Gigawatt supplies the energy for about 750,000 US homes) needed to lift Antarctic ocean water to heights of, on average, 640 metres, heat it, desalinate it and then spray it over 52,000 square kilometres of the West Antarctic ice sheet in the form of artificial snow, at the rate of several hundred billion tonnes a year, for decades.

Such action could slow or halt the apparently-inevitable collapse of the ice sheet: were this to melt entirely – and right now it is melting at the rate of 361 billion tonnes a year – the world’s oceans would rise by 3.3 metres.

“The fundamental trade-off is whether we as humanity want to sacrifice Antarctica to save the currently inhabited coastal regions and cultural heritage that we have built and are building on our shores,” said Anders Levermann of the Potsdam Institute for Climate Impact Research.

“The apparent absurdity of the endeavour to let it snow in Antarctica to stop an ice instability reflects the breathtaking dimension of the sea level problem”

“It is about global metropolises, from New York to Shanghai, which in the long term will be below sea level if nothing is done. The West Antarctic ice sheet is one of the tipping elements in our climate system. Ice loss is accelerating and might not stop until the West Antarctic ice sheet is practically gone.”

The Potsdam scientists report in the journal Science Advances that their simulations of ice loss from West Antarctica and the measures needed to halt such loss are not an alternative to other steps. Their calculations would be valid “only under a simultaneous drastic reduction” of the global carbon dioxide emissions that drive global heating, and sea level rise, in the first place.

That is, the world would need to abandon fossil fuels, agree to switch to renewable energy, and then use that renewable energy to in effect destroy the Antarctic’s unique ecosystem but save the great cities of the world from the advancing waves later in this millennium.

The researchers acknowledge that the solution is somewhere between impractical and impossible (in their words, it would have to be undertaken “under the difficult circumstances of the Antarctic climate”). But the mere fact that they could write such a proposal is itself an indicator of the accelerating seriousness of the planetary predicament.

In Paris in 2015, 195 nations agreed to take steps to limit global temperature rise to “well below” 2°C above the level that obtained for most of human history. Such steps for the most part have yet to be taken.

3°C rise possible

Carbon dioxide emissions are increasing, the Arctic ice cap is diminishing, the oceans are warming and the loss of ice in Antarctica is increasing.

By 2100, on present trends, the world will be at least 3°C above the historic average.

“The apparent absurdity of the endeavour to let it snow in Antarctica to stop an ice instability reflects the breathtaking dimension of the sea level problem,” Professor Levermann said.

“Yet as scientists we feel it is our duty to inform society about each and every potential option to counter the problems ahead.

“As unbelievable as it might seem, in order to prevent an unprecedented risk, humankind might have to make an unprecedented effort, too.” − Climate News Network

In theory, artificial snow could save the ice caps and limit sea level rise. But rescuing civilisation this way would sacrifice Antarctica.

LONDON, 2 August, 2019 − German scientists have proposed a startling new way of slowing sea level rise and saving New York, Shanghai, Amsterdam and Miami from 3.3 metres of ocean flooding − by using artificial snow.

They suggest the rising seas could be halted by turning West Antarctica, one of the last undisturbed places on Earth, into an industrial snow complex, complete with a sophisticated distribution system.

An estimated 12,000 high-performance wind turbines could be used to generate the 145 Gigawatts of power (one Gigawatt supplies the energy for about 750,000 US homes) needed to lift Antarctic ocean water to heights of, on average, 640 metres, heat it, desalinate it and then spray it over 52,000 square kilometres of the West Antarctic ice sheet in the form of artificial snow, at the rate of several hundred billion tonnes a year, for decades.

Such action could slow or halt the apparently-inevitable collapse of the ice sheet: were this to melt entirely – and right now it is melting at the rate of 361 billion tonnes a year – the world’s oceans would rise by 3.3 metres.

“The fundamental trade-off is whether we as humanity want to sacrifice Antarctica to save the currently inhabited coastal regions and cultural heritage that we have built and are building on our shores,” said Anders Levermann of the Potsdam Institute for Climate Impact Research.

“The apparent absurdity of the endeavour to let it snow in Antarctica to stop an ice instability reflects the breathtaking dimension of the sea level problem”

“It is about global metropolises, from New York to Shanghai, which in the long term will be below sea level if nothing is done. The West Antarctic ice sheet is one of the tipping elements in our climate system. Ice loss is accelerating and might not stop until the West Antarctic ice sheet is practically gone.”

The Potsdam scientists report in the journal Science Advances that their simulations of ice loss from West Antarctica and the measures needed to halt such loss are not an alternative to other steps. Their calculations would be valid “only under a simultaneous drastic reduction” of the global carbon dioxide emissions that drive global heating, and sea level rise, in the first place.

That is, the world would need to abandon fossil fuels, agree to switch to renewable energy, and then use that renewable energy to in effect destroy the Antarctic’s unique ecosystem but save the great cities of the world from the advancing waves later in this millennium.

The researchers acknowledge that the solution is somewhere between impractical and impossible (in their words, it would have to be undertaken “under the difficult circumstances of the Antarctic climate”). But the mere fact that they could write such a proposal is itself an indicator of the accelerating seriousness of the planetary predicament.

In Paris in 2015, 195 nations agreed to take steps to limit global temperature rise to “well below” 2°C above the level that obtained for most of human history. Such steps for the most part have yet to be taken.

3°C rise possible

Carbon dioxide emissions are increasing, the Arctic ice cap is diminishing, the oceans are warming and the loss of ice in Antarctica is increasing.

By 2100, on present trends, the world will be at least 3°C above the historic average.

“The apparent absurdity of the endeavour to let it snow in Antarctica to stop an ice instability reflects the breathtaking dimension of the sea level problem,” Professor Levermann said.

“Yet as scientists we feel it is our duty to inform society about each and every potential option to counter the problems ahead.

“As unbelievable as it might seem, in order to prevent an unprecedented risk, humankind might have to make an unprecedented effort, too.” − Climate News Network

Under-nutrition will grow in warmer world

Tomorrow’s world will not just be hungrier: it will increasingly face under-nutrition. More carbon dioxide means harvests with lower protein, iron and zinc.

LONDON, 1 August, 2019 − Climate change driven by ever-higher levels of carbon dioxide in the atmosphere will do more than just limit harvests. It will increase under-nutrition, making the planet’s staple foods less nourishing.

Put simply, the higher the use of fossil fuels, the greater the growth in the numbers of anaemic mothers, malnourished babies and stunted children, and the higher the count of overall deaths from malnutrition.

More than 2 million children of five years or less die each year from conditions associated with protein deficiency. Zinc deficiency is linked to 100,000 deaths a year, and iron levels to 200,000 deaths a year among young children.

And things will get worse. Over the next three decades, according to a new study in the journal Lancet Planetary Health, the combination of shocks from a hotter, stormier, more extreme world and ever-higher levels of atmospheric carbon dioxide will combine to make plant proteins, zinc and iron less available.

By 2050, levels of protein available per head could fall by 19.5% and of iron and zinc by 14.4% and 14.6% respectively. That is a fall of – for all three vital elements of survival – almost one fifth.

“Diet and human health are incredibly complex and difficult to predict, and by reducing the availability of critical nutrients, climate change will further complicate efforts to eliminate undernutrition worldwide”

Researchers warn that even though agricultural techniques have improved, even though markets are better at distributing food surpluses, and even though the extra carbon dioxide will act to add fertility to crops if atmospheric carbon levels continue to rise, dietary protein, iron and zinc will all fall by significant percentages in the harvests of 2050.

This will hold true for many of the world’s most important staples, among them wheat, rice, maize, barley, potatoes, soybeans and vegetables.

And many nations that already experience higher levels of malnutrition – in South Asia, the Middle East, sub-Saharan Africa, North Africa and the former Soviet Union − will continue to be disproportionately affected.

“We’ve made a lot of progress reducing under-nutrition around the world recently but global population growth over the next 30 years will require increasing production of foods that provide sufficient nutrients,” said Timothy Sulser of the International Food Policy Research Institute, one of the researchers.

Plant-based diet

“These findings suggest that climate change could slow progress on improvements in global nutrition by simply making key nutrients less available than they would be without it.”

The Lancet is one of the world’s oldest and most distinguished medical journals: it has at least twice comprehensively addressed aspects of climate change. At the start of this year it found that with a plant-based diet, it would be in theory possible to feed, and properly nourish, the 10 billion population expected later this century.

Late last year it also warned that, just in this century alone, extremes of temperature had threatened the health and economic growth of an additional 157 million people.

The latest study is a confirmation of earlier findings: other scientists have already warned that protein levels and micronutrient properties will be diminished in a greenhouse world.

Separate research has found that both the rice and wheat harvests of tomorrow could have less food value.

Famine threat

A third study has found that global fruit and vegetable production is already not enough to sustain a healthy population. And researchers have repeatedly warned that ever more-intense and frequent natural shocks that accompany global heating – floods, heat waves, drought, windstorm and so on – threaten food harvests worldwide and could even precipitate the kind of global famines last seen in the 19th century.

The researchers limited their horizon to 2050: they warn that, on present trends, problems with food nutrition levels are only likely to get worse in the decades beyond.

They also point out that the availability of nutrients is only part of the problem: the poorest also need access to clean water, sanitation and education to take advantage of any improved diet.

“Diet and human health are incredibly complex and difficult to predict, and by reducing the availability of critical nutrients, climate change will further complicate efforts to eliminate undernutrition worldwide,” Professor Sulser said. − Climate News Network

Tomorrow’s world will not just be hungrier: it will increasingly face under-nutrition. More carbon dioxide means harvests with lower protein, iron and zinc.

LONDON, 1 August, 2019 − Climate change driven by ever-higher levels of carbon dioxide in the atmosphere will do more than just limit harvests. It will increase under-nutrition, making the planet’s staple foods less nourishing.

Put simply, the higher the use of fossil fuels, the greater the growth in the numbers of anaemic mothers, malnourished babies and stunted children, and the higher the count of overall deaths from malnutrition.

More than 2 million children of five years or less die each year from conditions associated with protein deficiency. Zinc deficiency is linked to 100,000 deaths a year, and iron levels to 200,000 deaths a year among young children.

And things will get worse. Over the next three decades, according to a new study in the journal Lancet Planetary Health, the combination of shocks from a hotter, stormier, more extreme world and ever-higher levels of atmospheric carbon dioxide will combine to make plant proteins, zinc and iron less available.

By 2050, levels of protein available per head could fall by 19.5% and of iron and zinc by 14.4% and 14.6% respectively. That is a fall of – for all three vital elements of survival – almost one fifth.

“Diet and human health are incredibly complex and difficult to predict, and by reducing the availability of critical nutrients, climate change will further complicate efforts to eliminate undernutrition worldwide”

Researchers warn that even though agricultural techniques have improved, even though markets are better at distributing food surpluses, and even though the extra carbon dioxide will act to add fertility to crops if atmospheric carbon levels continue to rise, dietary protein, iron and zinc will all fall by significant percentages in the harvests of 2050.

This will hold true for many of the world’s most important staples, among them wheat, rice, maize, barley, potatoes, soybeans and vegetables.

And many nations that already experience higher levels of malnutrition – in South Asia, the Middle East, sub-Saharan Africa, North Africa and the former Soviet Union − will continue to be disproportionately affected.

“We’ve made a lot of progress reducing under-nutrition around the world recently but global population growth over the next 30 years will require increasing production of foods that provide sufficient nutrients,” said Timothy Sulser of the International Food Policy Research Institute, one of the researchers.

Plant-based diet

“These findings suggest that climate change could slow progress on improvements in global nutrition by simply making key nutrients less available than they would be without it.”

The Lancet is one of the world’s oldest and most distinguished medical journals: it has at least twice comprehensively addressed aspects of climate change. At the start of this year it found that with a plant-based diet, it would be in theory possible to feed, and properly nourish, the 10 billion population expected later this century.

Late last year it also warned that, just in this century alone, extremes of temperature had threatened the health and economic growth of an additional 157 million people.

The latest study is a confirmation of earlier findings: other scientists have already warned that protein levels and micronutrient properties will be diminished in a greenhouse world.

Separate research has found that both the rice and wheat harvests of tomorrow could have less food value.

Famine threat

A third study has found that global fruit and vegetable production is already not enough to sustain a healthy population. And researchers have repeatedly warned that ever more-intense and frequent natural shocks that accompany global heating – floods, heat waves, drought, windstorm and so on – threaten food harvests worldwide and could even precipitate the kind of global famines last seen in the 19th century.

The researchers limited their horizon to 2050: they warn that, on present trends, problems with food nutrition levels are only likely to get worse in the decades beyond.

They also point out that the availability of nutrients is only part of the problem: the poorest also need access to clean water, sanitation and education to take advantage of any improved diet.

“Diet and human health are incredibly complex and difficult to predict, and by reducing the availability of critical nutrients, climate change will further complicate efforts to eliminate undernutrition worldwide,” Professor Sulser said. − Climate News Network

Himalayan melt rate doubles in 40 years

The pace of glacier thawing on the roof of the world has doubled in 40 years, scientists say, with the Himalayan melt rate affected by climate heating.

LONDON, 20 June, 2019 − The Himalayan melt rate is now thawing glaciers on whose water many millions of lives depend twice as fast as just four decades ago, researchers say. One scientist thinks the glaciers may have lost a quarter of their mass in the last 40 years.

A new, comprehensive study shows the glaciers’ melting, caused by rising temperatures, has accelerated significantly since the turn of the century. The study, which draws on 40 years of satellite observations across India, China, Nepal and Bhutan, shows the glaciers have been losing the equivalent of more than 20 inches (about half a metre) of ice each year since 2000, twice the amount of melting recorded from 1975 to 2000.

The study, published in the journal Science Advances, is the latest to show the threat that climate change represents to the water supplies of hundreds of millions of people living downstream across much of Asia.

“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why,” said the lead author, Joshua Maurer, a Ph D candidate at Columbia University’s Lamont-Doherty Earth Observatory. While not specifically calculated in the study, the glaciers may have lost as much as a quarter of their mass over the last four decades, he said.

With around 600 billion tons of ice today, the Himalayas are sometimes called the Earth’s third pole. Many recent studies have suggested that the glaciers are dwindling, including one in February this year projecting that up to two-thirds of the current ice cover could be gone by 2100.

Wider picture

Until now, though, observations have usually focused on individual glaciers or specific regions, or on shorter lengths of time, and have sometimes produced contradictory results, on both the degree of ice loss and its causes. The new study incorporates data from across the region, stretching from early satellite observations to the present.

This shows the melting is consistent over time and in different areas, and that rising temperatures are to blame: they vary from place to place, but from 2000 to 2016 they have averaged 1°C (1.8°F) higher than those from 1975 to 2000.

Maurer and his co-authors analysed repeat satellite images of about 650 glaciers spanning 2,000 kilometres. Many of the 20th-century observations came from recently declassified photographic images taken by US spy satellites.

The researchers created an automated system to turn these into three-dimensional models that could show the changing elevations of glaciers over time. They then compared these images with post-2000 optical data from more sophisticated satellites, which show elevation changes more directly.

“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why”

They found that from 1975 to 2000, glaciers across the region lost an average of about 0.25 metres (10 inches) of ice each year in the face of slight warming. Following a more pronounced warming trend which started in the 1990s, from 2000 the loss accelerated to about half a metre annually.

Recent yearly losses have averaged about 8 billion tons of water, Maurer says. On most glaciers the melting has been concentrated mainly at lower elevations, where some ice surfaces are losing as much as 5 metres (16 feet) a year.

Despite suggestions that changes in precipitation, or increasing deposits of soot from growing fossil fuel burning in Asia, might be affecting the glaciers rather than climate heating, Maurer believes rising temperature is the main cause of the melting.

“It looks just like what we would expect if warming were the dominant driver of ice loss,” he said. At least one recent study has found a similar process at work in Alaska.

Alpine parallel

Ice loss in the Himalayas resembles the much more closely studied European Alps, where temperatures started going up a little earlier, in the 1980s. Glaciers there began melting soon after that, and rapid ice loss has continued since. The Himalayas are generally not melting as fast as the Alps, but their changes are similar, the researchers say.

Their study does not include the huge adjoining ranges of high-mountain Asia such as the Pamir, Hindu Kush or Tian Shan, but other studies suggest similar melting is under way there as well.

About 800 million people depend in part on seasonal runoff from Himalayan glaciers for irrigation, hydropower and drinking water. The faster melting appears so far to be increasing runoff during warm seasons, but scientists think this will slow within decades as the glaciers lose mass, eventually leading to water shortages.

In many high mountain areas meltwater lakes are building up rapidly behind natural dams of rocky debris, threatening downstream communities with outburst floods. On Everest, the long-lost bodies of climbers who failed to return from the summits are emerging from the melting ice. − Climate News Network

The pace of glacier thawing on the roof of the world has doubled in 40 years, scientists say, with the Himalayan melt rate affected by climate heating.

LONDON, 20 June, 2019 − The Himalayan melt rate is now thawing glaciers on whose water many millions of lives depend twice as fast as just four decades ago, researchers say. One scientist thinks the glaciers may have lost a quarter of their mass in the last 40 years.

A new, comprehensive study shows the glaciers’ melting, caused by rising temperatures, has accelerated significantly since the turn of the century. The study, which draws on 40 years of satellite observations across India, China, Nepal and Bhutan, shows the glaciers have been losing the equivalent of more than 20 inches (about half a metre) of ice each year since 2000, twice the amount of melting recorded from 1975 to 2000.

The study, published in the journal Science Advances, is the latest to show the threat that climate change represents to the water supplies of hundreds of millions of people living downstream across much of Asia.

“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why,” said the lead author, Joshua Maurer, a Ph D candidate at Columbia University’s Lamont-Doherty Earth Observatory. While not specifically calculated in the study, the glaciers may have lost as much as a quarter of their mass over the last four decades, he said.

With around 600 billion tons of ice today, the Himalayas are sometimes called the Earth’s third pole. Many recent studies have suggested that the glaciers are dwindling, including one in February this year projecting that up to two-thirds of the current ice cover could be gone by 2100.

Wider picture

Until now, though, observations have usually focused on individual glaciers or specific regions, or on shorter lengths of time, and have sometimes produced contradictory results, on both the degree of ice loss and its causes. The new study incorporates data from across the region, stretching from early satellite observations to the present.

This shows the melting is consistent over time and in different areas, and that rising temperatures are to blame: they vary from place to place, but from 2000 to 2016 they have averaged 1°C (1.8°F) higher than those from 1975 to 2000.

Maurer and his co-authors analysed repeat satellite images of about 650 glaciers spanning 2,000 kilometres. Many of the 20th-century observations came from recently declassified photographic images taken by US spy satellites.

The researchers created an automated system to turn these into three-dimensional models that could show the changing elevations of glaciers over time. They then compared these images with post-2000 optical data from more sophisticated satellites, which show elevation changes more directly.

“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why”

They found that from 1975 to 2000, glaciers across the region lost an average of about 0.25 metres (10 inches) of ice each year in the face of slight warming. Following a more pronounced warming trend which started in the 1990s, from 2000 the loss accelerated to about half a metre annually.

Recent yearly losses have averaged about 8 billion tons of water, Maurer says. On most glaciers the melting has been concentrated mainly at lower elevations, where some ice surfaces are losing as much as 5 metres (16 feet) a year.

Despite suggestions that changes in precipitation, or increasing deposits of soot from growing fossil fuel burning in Asia, might be affecting the glaciers rather than climate heating, Maurer believes rising temperature is the main cause of the melting.

“It looks just like what we would expect if warming were the dominant driver of ice loss,” he said. At least one recent study has found a similar process at work in Alaska.

Alpine parallel

Ice loss in the Himalayas resembles the much more closely studied European Alps, where temperatures started going up a little earlier, in the 1980s. Glaciers there began melting soon after that, and rapid ice loss has continued since. The Himalayas are generally not melting as fast as the Alps, but their changes are similar, the researchers say.

Their study does not include the huge adjoining ranges of high-mountain Asia such as the Pamir, Hindu Kush or Tian Shan, but other studies suggest similar melting is under way there as well.

About 800 million people depend in part on seasonal runoff from Himalayan glaciers for irrigation, hydropower and drinking water. The faster melting appears so far to be increasing runoff during warm seasons, but scientists think this will slow within decades as the glaciers lose mass, eventually leading to water shortages.

In many high mountain areas meltwater lakes are building up rapidly behind natural dams of rocky debris, threatening downstream communities with outburst floods. On Everest, the long-lost bodies of climbers who failed to return from the summits are emerging from the melting ice. − Climate News Network

Rising US heat spurs urban rats’ numbers

It may not be the sole cause of US urban rats’ rising numbers, but climate change’s growing heat is probably implicated.

LONDON, 12 June, 2019 − In the heat of a US summer, urban rats’ thoughts focus on one goal: it’s reproduction time, as the media make clear.

They go for the type of headlines which send shivers down the spine. “Rats love climate change”, says one. “Climate change is scary; rat explosion is scarier”, says another.

Reports from several cities in the US indicate that city rat populations are increasing, and many point to climate change as a primary cause of what is a growing rodent problem.

The actual reasons for what some of the more florid commentators refer to as a “ratpocalypse” are difficult to gauge. Little research has been carried out.

Take, for example, New York City. Estimates of the size of the city’s rat population – the human population is 8.6 million – range anywhere between 2 and 32 million.

“The brown rat, or Rattus norvegicus, common on the US east coast, can produce six litters a year with an average of 12 pups per litter”

While the figures might be vague, there’s general agreement that the city’s rat numbers are growing substantially. Calls to vermin controllers have increased. City officials say the incidence of rat sightings has gone up by nearly 40% over the last five years.

Rats can be vectors, or carriers, of disease and can transmit ticks and fleas. They can also do considerable damage to vital infrastructure, gnawing through wires and damaging pavements and drainage systems by their burrowing.

In cold weather rats tend to be inactive and stay in their burrows. With milder winters and rising average temperatures, rats’ breeding season is extended.

Rats reproduce at a prolific rate; the brown rat, or Rattus norvegicus, common on the US east coast, can produce six litters a year with an average of 12 pups per litter.

“Everywhere I go, rat populations are up”, a research scientist told the New York Times newspaper.

More city residents

Other US cities report similar rat infestations; Chicago is said to have a particularly serious rodent problem.

While increased temperatures are believed to be one cause of the growth in rat populations, other factors are involved. In the US and around the world, more and more people are choosing to live in cities.

By 2050, it’s estimated that 70% of the world’s population will be urban-based. More people in tightly-packed areas means more food being accumulated and more rubbish. Inefficient waste collection facilities in many urban areas inevitably lead to a growth in rodent numbers.

Surprisingly, there seems to have been little research into urban rats, their behaviour and the size of populations in various cities.

One problem encountered by researchers is that many urban dwellers, particularly landlords, are reluctant to admit to rat infestation problems – or to highlight the issue by allowing scientists to carry out surveys on their premises. − Climate News Network

It may not be the sole cause of US urban rats’ rising numbers, but climate change’s growing heat is probably implicated.

LONDON, 12 June, 2019 − In the heat of a US summer, urban rats’ thoughts focus on one goal: it’s reproduction time, as the media make clear.

They go for the type of headlines which send shivers down the spine. “Rats love climate change”, says one. “Climate change is scary; rat explosion is scarier”, says another.

Reports from several cities in the US indicate that city rat populations are increasing, and many point to climate change as a primary cause of what is a growing rodent problem.

The actual reasons for what some of the more florid commentators refer to as a “ratpocalypse” are difficult to gauge. Little research has been carried out.

Take, for example, New York City. Estimates of the size of the city’s rat population – the human population is 8.6 million – range anywhere between 2 and 32 million.

“The brown rat, or Rattus norvegicus, common on the US east coast, can produce six litters a year with an average of 12 pups per litter”

While the figures might be vague, there’s general agreement that the city’s rat numbers are growing substantially. Calls to vermin controllers have increased. City officials say the incidence of rat sightings has gone up by nearly 40% over the last five years.

Rats can be vectors, or carriers, of disease and can transmit ticks and fleas. They can also do considerable damage to vital infrastructure, gnawing through wires and damaging pavements and drainage systems by their burrowing.

In cold weather rats tend to be inactive and stay in their burrows. With milder winters and rising average temperatures, rats’ breeding season is extended.

Rats reproduce at a prolific rate; the brown rat, or Rattus norvegicus, common on the US east coast, can produce six litters a year with an average of 12 pups per litter.

“Everywhere I go, rat populations are up”, a research scientist told the New York Times newspaper.

More city residents

Other US cities report similar rat infestations; Chicago is said to have a particularly serious rodent problem.

While increased temperatures are believed to be one cause of the growth in rat populations, other factors are involved. In the US and around the world, more and more people are choosing to live in cities.

By 2050, it’s estimated that 70% of the world’s population will be urban-based. More people in tightly-packed areas means more food being accumulated and more rubbish. Inefficient waste collection facilities in many urban areas inevitably lead to a growth in rodent numbers.

Surprisingly, there seems to have been little research into urban rats, their behaviour and the size of populations in various cities.

One problem encountered by researchers is that many urban dwellers, particularly landlords, are reluctant to admit to rat infestation problems – or to highlight the issue by allowing scientists to carry out surveys on their premises. − Climate News Network

Thirty years to climate meltdown – or not?

For years most of us largely ignored the idea of climate meltdown. Now we’re talking about it. So what should we be doing?

LONDON, 10 June, 2019 − How much of a threat is climate meltdown? Should we treat it as the biggest danger to life in the 21st century, or as one of many problems − serious, but manageable?

A new study says human civilisation itself could pass the point of no return by 2050. The Australian climate think-tank Breakthrough: National Centre for Climate Restoration says that unless humanity takes drastic and immediate action to save the climate, a combination of unstable food production, water shortages and extreme weather could lead to the breakdown of global society.

One renowned US climate scientist, Michael Mann of Pennsylvania State University, says that Breakthrough is exaggerating and its report could be counter-productive.

In the UK, though, Mark Maslin of University College London says the report underlines the deep concerns expressed by some security experts.

Act together

Chris Barrie, a retired Royal Australian Navy admiral and former Chief of the Australian Defence Force, is now an honorary professor at the Australian National University, Canberra.

In a foreword to the Breakthrough study he writes: “We must act collectively. We need strong, determined leadership in government, in business and in our communities to ensure a sustainable future for humankind.”

David Spratt, Breakthrough’s research director and a co-author of the study, says that “much knowledge produced for policymakers is too conservative,” but that the new paper, by showing the extreme end of what could happen in just the next three decades, aims to make the stakes clear. “The report speaks, in our opinion, a harsh but necessary truth,” he says.

“To reduce this risk and protect human civilisation, a massive global mobilisation of resources is needed in the coming decade to build a zero-emissions industrial system and set in train the restoration of a safe climate,” the report reads. “This would be akin in scale to the World War II emergency mobilisation.”

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly”

Breakthrough acknowledges that the worst possibility it foresees − the total collapse of civilisation by mid-century − is an example of a worst-case scenario, but it insists that “the world is currently completely unprepared to envisage, and even less deal with, the consequences of catastrophic climate change.”

The picture of the possible near future it presents is stark. By 2050, it says, the world could have reached:

  • a 3°C temperature rise, with a further 1°C in store
  • sea levels 0.5 metres above today’s, with a possible eventual rise of 25m
  • 55% of the world’s people subject to more than 20 days a year of heat “beyond the threshold of human survivability”
  • one billion people forced to leave the tropics
  • a 20% decline in crop yields, leaving too little food to feed the world
  • armed conflict likely and nuclear war possible.

The report’s authors conclude: “The scale of destruction is beyond our capacity to model, with a high likelihood of human civilisation coming to an end.”

Warnings examined

Warnings of the possible end of human civilisation are not new. They range from those which offer highly-qualified hope for humanity’s future to others which find very little to celebrate, even tentatively.

The Breakthrough study fits unequivocally into the second group. To weigh the credibility of some of its statements, the journal New Scientist looks at the sources they cite and the wider context of the claims they make.

Its scrutiny ends with the views of two eminent climate scientists. Michael Mann, professor of atmospheric science at Penn State, says: “I respect the authors and appreciate that their intentions are good, but … overblown rhetoric, exaggeration, and unsupportable doomist framing can be counteractive to climate action.”

For his part, Mark Maslin, professor of geography at UCL, tells New Scientist that the Breakthrough report adds to the deep concerns expressed by security experts such as the Pentagon over climate change.

Hope nurtured

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly,” he says.

The 2020 round of UN climate negotiations is due to take place in November next year, with hopes building that many countries will agree then to make much more radical cuts in greenhouse gas emissions than they have pledged so far.

Altogether 195 countries promised in 2015, in the Paris Agreement, to make the cuts needed to prevent global average temperatures rising more than 2°C, and if possible to stay below a maximum rise of 1.5°C, the levels climate scientists say are the highest that can assure the planet’s safety. But the cuts that many countries have promised so far will not achieve either goal.

Scientists say it is still possible for the world to achieve the 1.5°C limit. But doing so requires immediate emissions cuts, on a scale and at a pace that are not yet in sight − “a very big ‘if’”, as one of them put it. − Climate News Network

For years most of us largely ignored the idea of climate meltdown. Now we’re talking about it. So what should we be doing?

LONDON, 10 June, 2019 − How much of a threat is climate meltdown? Should we treat it as the biggest danger to life in the 21st century, or as one of many problems − serious, but manageable?

A new study says human civilisation itself could pass the point of no return by 2050. The Australian climate think-tank Breakthrough: National Centre for Climate Restoration says that unless humanity takes drastic and immediate action to save the climate, a combination of unstable food production, water shortages and extreme weather could lead to the breakdown of global society.

One renowned US climate scientist, Michael Mann of Pennsylvania State University, says that Breakthrough is exaggerating and its report could be counter-productive.

In the UK, though, Mark Maslin of University College London says the report underlines the deep concerns expressed by some security experts.

Act together

Chris Barrie, a retired Royal Australian Navy admiral and former Chief of the Australian Defence Force, is now an honorary professor at the Australian National University, Canberra.

In a foreword to the Breakthrough study he writes: “We must act collectively. We need strong, determined leadership in government, in business and in our communities to ensure a sustainable future for humankind.”

David Spratt, Breakthrough’s research director and a co-author of the study, says that “much knowledge produced for policymakers is too conservative,” but that the new paper, by showing the extreme end of what could happen in just the next three decades, aims to make the stakes clear. “The report speaks, in our opinion, a harsh but necessary truth,” he says.

“To reduce this risk and protect human civilisation, a massive global mobilisation of resources is needed in the coming decade to build a zero-emissions industrial system and set in train the restoration of a safe climate,” the report reads. “This would be akin in scale to the World War II emergency mobilisation.”

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly”

Breakthrough acknowledges that the worst possibility it foresees − the total collapse of civilisation by mid-century − is an example of a worst-case scenario, but it insists that “the world is currently completely unprepared to envisage, and even less deal with, the consequences of catastrophic climate change.”

The picture of the possible near future it presents is stark. By 2050, it says, the world could have reached:

  • a 3°C temperature rise, with a further 1°C in store
  • sea levels 0.5 metres above today’s, with a possible eventual rise of 25m
  • 55% of the world’s people subject to more than 20 days a year of heat “beyond the threshold of human survivability”
  • one billion people forced to leave the tropics
  • a 20% decline in crop yields, leaving too little food to feed the world
  • armed conflict likely and nuclear war possible.

The report’s authors conclude: “The scale of destruction is beyond our capacity to model, with a high likelihood of human civilisation coming to an end.”

Warnings examined

Warnings of the possible end of human civilisation are not new. They range from those which offer highly-qualified hope for humanity’s future to others which find very little to celebrate, even tentatively.

The Breakthrough study fits unequivocally into the second group. To weigh the credibility of some of its statements, the journal New Scientist looks at the sources they cite and the wider context of the claims they make.

Its scrutiny ends with the views of two eminent climate scientists. Michael Mann, professor of atmospheric science at Penn State, says: “I respect the authors and appreciate that their intentions are good, but … overblown rhetoric, exaggeration, and unsupportable doomist framing can be counteractive to climate action.”

For his part, Mark Maslin, professor of geography at UCL, tells New Scientist that the Breakthrough report adds to the deep concerns expressed by security experts such as the Pentagon over climate change.

Hope nurtured

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly,” he says.

The 2020 round of UN climate negotiations is due to take place in November next year, with hopes building that many countries will agree then to make much more radical cuts in greenhouse gas emissions than they have pledged so far.

Altogether 195 countries promised in 2015, in the Paris Agreement, to make the cuts needed to prevent global average temperatures rising more than 2°C, and if possible to stay below a maximum rise of 1.5°C, the levels climate scientists say are the highest that can assure the planet’s safety. But the cuts that many countries have promised so far will not achieve either goal.

Scientists say it is still possible for the world to achieve the 1.5°C limit. But doing so requires immediate emissions cuts, on a scale and at a pace that are not yet in sight − “a very big ‘if’”, as one of them put it. − Climate News Network

Siberia expects mass migration as it warms

Scientists mapping the effects of increased temperature and rainfall across Siberia say it could expect mass migration in a warmer world.

LONDON, 7 June, 2019 − Siberia, currently one of the most sparsely populated places in the northern hemisphere, could become a target for mass migration as the climate warms.

By 2080, scientists report, melting permafrost and warming summer and winter temperatures will mean that agriculture could thrive and support between five and seven times the current population.

Lands to the south are becoming far less able to feed and sustain their existing populations, as heat makes crops harder to grow and cities untenable, and mass migration northward is likely, the scientists predict.

Their study, which is produced by the Krasnoyarsk Federal Research Centre in Siberia and the US National Institute of Aerospace, says the current problem of falling population in Russia will be reversed as conditions in Siberia become much better for growing food, and both summers and winters more pleasant to live in. It is published in the journal Environmental Research Letters.

With 13 million square kilometres of land area, Asian Russia – east of the Urals, towards the Pacific – accounts for 77% of Russian territory. Its population, however, accounts for just 27% of the country’s people and is concentrated along the forest-steppe in the south, with its comfortable climate and fertile soil.

“In a future, warmer climate, food security, in terms of crop distribution and production capability, is predicted to become more favourable”

The findings have a certain irony, because at the close of the Communist era the Soviet government was not keen to take any action on climate change: it saw the warming of Siberia as a chance for the USSR to grow more wheat and challenge US dominance of the world’s grain supply.

The scientists warn, however, that mass migration will not be that simple. The melting of the permafrost threatens what little infrastructure there is in the region. Before a larger population could provide for itself, investments need to be made in new roads, railways and power supplies to support it.

They say warming in the region already exceeds earlier estimates. Depending on how much carbon dioxide humans continue to pump into the atmosphere, the scientists predict mid-winter temperatures over Asian Russia will increase between 3.4°C and 9.1°C by 2080. Increases in mid-summer will be between 1.9°C and 5.7°C, they say.

Permafrost, which currently covers 65% of the region, would fall to 40% by 2080, and crucially there will be increases in rainfall of between 60 mm and 140 mm, making the unfrozen area much more favourable for crops.

Migration ‘probable’

Using something called Ecological Landscape Potential, or ELP, to gauge the potential for land to support human populations, the scientists came to the conclusion that mass migration north was probable.

“We found the ELP would increase over most of Asian Russia, which would lead to a five- to seven-fold increase in the capacity of the territory to sustain and become attractive to human populations, which would then lead to migrations from less sustainable lands to Asian Russia during this century,” they say.

Dr Elena Parfenova, from the Krasnoyarsk centre, said: “In a future, warmer climate, food security, in terms of crop distribution and production capability, is predicted to become more favourable to support settlements in what is currently an extremely cold Asian Russia.”

She said that obviously people would flock first to the already developed areas in the south, but most of the area of Siberia and the Far East “have poorly developed infrastructure. The rapidity that these developments occur is dependent on investments in infrastructure and agriculture, which is dependent on the decisions that will be made in the near future.” − Climate News Network

Scientists mapping the effects of increased temperature and rainfall across Siberia say it could expect mass migration in a warmer world.

LONDON, 7 June, 2019 − Siberia, currently one of the most sparsely populated places in the northern hemisphere, could become a target for mass migration as the climate warms.

By 2080, scientists report, melting permafrost and warming summer and winter temperatures will mean that agriculture could thrive and support between five and seven times the current population.

Lands to the south are becoming far less able to feed and sustain their existing populations, as heat makes crops harder to grow and cities untenable, and mass migration northward is likely, the scientists predict.

Their study, which is produced by the Krasnoyarsk Federal Research Centre in Siberia and the US National Institute of Aerospace, says the current problem of falling population in Russia will be reversed as conditions in Siberia become much better for growing food, and both summers and winters more pleasant to live in. It is published in the journal Environmental Research Letters.

With 13 million square kilometres of land area, Asian Russia – east of the Urals, towards the Pacific – accounts for 77% of Russian territory. Its population, however, accounts for just 27% of the country’s people and is concentrated along the forest-steppe in the south, with its comfortable climate and fertile soil.

“In a future, warmer climate, food security, in terms of crop distribution and production capability, is predicted to become more favourable”

The findings have a certain irony, because at the close of the Communist era the Soviet government was not keen to take any action on climate change: it saw the warming of Siberia as a chance for the USSR to grow more wheat and challenge US dominance of the world’s grain supply.

The scientists warn, however, that mass migration will not be that simple. The melting of the permafrost threatens what little infrastructure there is in the region. Before a larger population could provide for itself, investments need to be made in new roads, railways and power supplies to support it.

They say warming in the region already exceeds earlier estimates. Depending on how much carbon dioxide humans continue to pump into the atmosphere, the scientists predict mid-winter temperatures over Asian Russia will increase between 3.4°C and 9.1°C by 2080. Increases in mid-summer will be between 1.9°C and 5.7°C, they say.

Permafrost, which currently covers 65% of the region, would fall to 40% by 2080, and crucially there will be increases in rainfall of between 60 mm and 140 mm, making the unfrozen area much more favourable for crops.

Migration ‘probable’

Using something called Ecological Landscape Potential, or ELP, to gauge the potential for land to support human populations, the scientists came to the conclusion that mass migration north was probable.

“We found the ELP would increase over most of Asian Russia, which would lead to a five- to seven-fold increase in the capacity of the territory to sustain and become attractive to human populations, which would then lead to migrations from less sustainable lands to Asian Russia during this century,” they say.

Dr Elena Parfenova, from the Krasnoyarsk centre, said: “In a future, warmer climate, food security, in terms of crop distribution and production capability, is predicted to become more favourable to support settlements in what is currently an extremely cold Asian Russia.”

She said that obviously people would flock first to the already developed areas in the south, but most of the area of Siberia and the Far East “have poorly developed infrastructure. The rapidity that these developments occur is dependent on investments in infrastructure and agriculture, which is dependent on the decisions that will be made in the near future.” − Climate News Network

Arctic sea ice loss affects the jet stream

The jet stream affects northern hemisphere climates. And global warming affects the behaviour of the jet stream. Prepare for yet more extremes of seasonal weather.

LONDON, 6 June, 2019 − Did you shiver in a winter ice storm? Could you wilt in a protracted heatwave this summer? German scientists have just identified the guilty agency and delivered the evidence implicating the jet stream.

Blame it on Arctic warming, they conclude: the retreat of the sea ice over the polar ocean has distorted the pattern of flow of the stratospheric winds usually known as the jet stream.

It is not a new idea. But this time, scientists have employed artificial intelligence and a machine-learning programme to accurately model the changes in the jet stream and then link these to changes in the chemistry of the upper atmosphere, and increasing patterns of twisting waves in the high altitude winds which then distort seasonal weather in the northern hemisphere mid-latitudes. They describe their research in the journal Scientific Reports.

“Our study shows that the changes in the jet stream are at least partly due to the loss of Arctic sea ice. If the ice cover continues to dwindle, we believe that both the frequency and intensity of the extreme weather events previously observed in the middle latitudes will increase,” said Markus Rex, who heads atmospheric research at the Alfred Wegener Institute in Potsdam, Germany.

Cold bouts explained

“In addition, our findings confirm that the more frequently occurring cold phases in winter in the USA, Europe and Asia are by no means a contradiction to global warming; rather they are part of anthropogenic climate change.”

The jet stream – exploited by jet aircraft on the trans-Atlantic routes – is made up of westerly winds that, at an altitude of 10 kilometres, stream around the planet in the mid-latitudes, at speeds of up to 500 km an hour, and push weather systems from west to east.

But researchers have already observed this: they have been changing, in response to global warming and in particular to the rapid warming of the Arctic, as greenhouse gas ratios in the atmosphere rise, and go on rising, in response to profligate human combustion of fossil fuels.

Rather than stick to a course more or less parallel to the Equator, these winds have been observed describing dramatic waves.

“If the ice cover continues to dwindle, we believe that both the frequency and intensity of the extreme weather events previously observed in the middle latitudes will increase”

These twists of direction have been linked to blasts of Arctic air into regions that could normally expect relatively mild winters: in particular to the ferocious cold that hit the US Midwest in January 2019.

These winds have also weakened and been linked to prolonged drought and extremes of heat that hit Europe in 2003, 2006, 2015 and 2018.

But association is not the same as demonstration of cause-and-effect. The Potsdam scientists wanted surer evidence. And their new climate simulations now include a machine-learning component that accounts for ozone chemistry at high altitudes.

And what their new model found was that as the Arctic sea ice retreats, the atmospheric waves have warmed the polar stratosphere in ways that have been amplified by the behaviour of the ozone layer.

Ozone response

Since what powers the jet stream is the difference between the cold Arctic and the warm tropics, the jet stream has weakened, and begun to meander, like a river flowing across a flood plain towards the sea.

In effect, the new study introduces a new piece to the climate puzzle: the response of the ozone layer and its role in the play of winds around the planet. The pay-off could be a clearer picture of things to come.

“We are now for the first time employing artificial intelligence in climate modelling, helping us arrive at more realistic model systems,” said Professor Rex.

“This holds tremendous potential for future climate models, which we believe will deliver more reliable climate projections and therefore a more robust basis for political decision-making.” − Climate News Network

The jet stream affects northern hemisphere climates. And global warming affects the behaviour of the jet stream. Prepare for yet more extremes of seasonal weather.

LONDON, 6 June, 2019 − Did you shiver in a winter ice storm? Could you wilt in a protracted heatwave this summer? German scientists have just identified the guilty agency and delivered the evidence implicating the jet stream.

Blame it on Arctic warming, they conclude: the retreat of the sea ice over the polar ocean has distorted the pattern of flow of the stratospheric winds usually known as the jet stream.

It is not a new idea. But this time, scientists have employed artificial intelligence and a machine-learning programme to accurately model the changes in the jet stream and then link these to changes in the chemistry of the upper atmosphere, and increasing patterns of twisting waves in the high altitude winds which then distort seasonal weather in the northern hemisphere mid-latitudes. They describe their research in the journal Scientific Reports.

“Our study shows that the changes in the jet stream are at least partly due to the loss of Arctic sea ice. If the ice cover continues to dwindle, we believe that both the frequency and intensity of the extreme weather events previously observed in the middle latitudes will increase,” said Markus Rex, who heads atmospheric research at the Alfred Wegener Institute in Potsdam, Germany.

Cold bouts explained

“In addition, our findings confirm that the more frequently occurring cold phases in winter in the USA, Europe and Asia are by no means a contradiction to global warming; rather they are part of anthropogenic climate change.”

The jet stream – exploited by jet aircraft on the trans-Atlantic routes – is made up of westerly winds that, at an altitude of 10 kilometres, stream around the planet in the mid-latitudes, at speeds of up to 500 km an hour, and push weather systems from west to east.

But researchers have already observed this: they have been changing, in response to global warming and in particular to the rapid warming of the Arctic, as greenhouse gas ratios in the atmosphere rise, and go on rising, in response to profligate human combustion of fossil fuels.

Rather than stick to a course more or less parallel to the Equator, these winds have been observed describing dramatic waves.

“If the ice cover continues to dwindle, we believe that both the frequency and intensity of the extreme weather events previously observed in the middle latitudes will increase”

These twists of direction have been linked to blasts of Arctic air into regions that could normally expect relatively mild winters: in particular to the ferocious cold that hit the US Midwest in January 2019.

These winds have also weakened and been linked to prolonged drought and extremes of heat that hit Europe in 2003, 2006, 2015 and 2018.

But association is not the same as demonstration of cause-and-effect. The Potsdam scientists wanted surer evidence. And their new climate simulations now include a machine-learning component that accounts for ozone chemistry at high altitudes.

And what their new model found was that as the Arctic sea ice retreats, the atmospheric waves have warmed the polar stratosphere in ways that have been amplified by the behaviour of the ozone layer.

Ozone response

Since what powers the jet stream is the difference between the cold Arctic and the warm tropics, the jet stream has weakened, and begun to meander, like a river flowing across a flood plain towards the sea.

In effect, the new study introduces a new piece to the climate puzzle: the response of the ozone layer and its role in the play of winds around the planet. The pay-off could be a clearer picture of things to come.

“We are now for the first time employing artificial intelligence in climate modelling, helping us arrive at more realistic model systems,” said Professor Rex.

“This holds tremendous potential for future climate models, which we believe will deliver more reliable climate projections and therefore a more robust basis for political decision-making.” − Climate News Network