Category Archives: Emissions

Carbon release set off Earth’s biggest extinction

A chain of calamities caused the planet’s biggest extinction, the greatest mass dying ever. Greenhouse gases explain how.

LONDON, 23 October, 2020 − German scientists are now sure they can explain the biggest extinction of life on this planet: a catastrophe at the end of the Permian Epoch 252 million years ago.

It happened because atmospheric carbon dioxide (CO2) levels rose dramatically over thousands of years, turning the seas ever more acidic, to precipitate dangerous changes in oceanic conditions. In this, so far the greatest of life’s periodic extinctions, 95% of all the sea creatures perished, along with three-quarters of all life on land.

The evidence of dramatic change at a particular level in the geological record − the Permian-Triassic boundary, now more precisely dated at 251.9 million years ago − has been teasing geologists for decades. And climate change through one agency or another has been a favoured candidate from the start.

That moment in vanished history was marked by a long, slow but world-changing series of volcanic eruptions − the evidence lies in great sheets of basalt known to geologists as the Siberian Traps − and since outgassing of carbon dioxide is associated with all volcanic eruption, a greenhouse effect driven by carbon dioxide has long been a favourite.

Seeking proof

So devastating was this release of heat from the deep crust that ancient coal deposits laid down in the Carboniferous may have ignited, to create the first-ever fossil fuel emissions.

But circumstantial evidence was not the same thing as proof. Dramatic ozone loss − ozone forms a shield against potentially lethal ultra-violet radiation in the upper atmosphere − has also been named as a suspect. Until somebody could deliver clear evidence of the machinery that ensured the extinction, the verdict could only be “not proven.”

Right now, with human help, the planet Earth is undergoing what has been termed a sixth great mass extinction, and evidence from the Permian extinction provides a lesson for what could happen in a changing climate, but so far simply that: an awful warning, rather than a dreadful example.

Now European researchers report in Nature Geoscience that they think they have settled the matter. They used evidence from fossils exposed in the Italian Alps to recreate the conditions in the ancient ocean.

“Humanity’s CO2 emission rate is currently fourteen times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth’s history”

The story told by the changing isotopes of carbon, oxygen and most importantly boron in a series of brachiopod fossils was of “substantial” change in the chemistry of sea water 252 million years ago: a change that could be linked to the carbon dioxide from the Siberian Traps eruptions.

The researchers took the reasoning a step further: they used computer models to simulate the conditions of the time. The world warmed, the oceans became increasingly acidic, and right at the outset those organisms in the sea that build shells from calcium were snuffed out of existence.

But the higher temperatures, greater evaporation and ever-higher rainfall that mark a greenhouse world meant ever-greater chemical weathering on land itself. So more nutrients flowed from land to ocean, to deliver too much fertiliser, to encourage too much algal growth.

What followed was a dramatic depletion of dissolved oxygen: marine life was increasingly stifled, or poisoned by sporadic sulphide concentration.

Chain reaction

“We are dealing with a cascading catastrophe in which the rise of CO2 in the atmosphere set off a chain of events that successively extinguished almost all life in the seas,” said Hana Jurikova, then of the Helmholtz Centre for Ocean Research in Kiel, Germany, but now at St Andrew’s in Scotland, who led the study.

It is an axiom of geological research that the present is key to the past, but her forensic account of ancient mayhem may not be a precise lesson for today.

“Ancient volcanic eruptions of this kind are not directly comparable to anthropogenic carbon emissions, and in fact all modern fossil fuel reserves are far too insufficient to release as much CO2 over hundreds of years, let alone thousands of years as was released 252 million years ago,” said Dr Jurikova.

“But it is astonishing that humanity’s CO2 emission rate is currently fourteen times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth’s history”. − Climate News Network

A chain of calamities caused the planet’s biggest extinction, the greatest mass dying ever. Greenhouse gases explain how.

LONDON, 23 October, 2020 − German scientists are now sure they can explain the biggest extinction of life on this planet: a catastrophe at the end of the Permian Epoch 252 million years ago.

It happened because atmospheric carbon dioxide (CO2) levels rose dramatically over thousands of years, turning the seas ever more acidic, to precipitate dangerous changes in oceanic conditions. In this, so far the greatest of life’s periodic extinctions, 95% of all the sea creatures perished, along with three-quarters of all life on land.

The evidence of dramatic change at a particular level in the geological record − the Permian-Triassic boundary, now more precisely dated at 251.9 million years ago − has been teasing geologists for decades. And climate change through one agency or another has been a favoured candidate from the start.

That moment in vanished history was marked by a long, slow but world-changing series of volcanic eruptions − the evidence lies in great sheets of basalt known to geologists as the Siberian Traps − and since outgassing of carbon dioxide is associated with all volcanic eruption, a greenhouse effect driven by carbon dioxide has long been a favourite.

Seeking proof

So devastating was this release of heat from the deep crust that ancient coal deposits laid down in the Carboniferous may have ignited, to create the first-ever fossil fuel emissions.

But circumstantial evidence was not the same thing as proof. Dramatic ozone loss − ozone forms a shield against potentially lethal ultra-violet radiation in the upper atmosphere − has also been named as a suspect. Until somebody could deliver clear evidence of the machinery that ensured the extinction, the verdict could only be “not proven.”

Right now, with human help, the planet Earth is undergoing what has been termed a sixth great mass extinction, and evidence from the Permian extinction provides a lesson for what could happen in a changing climate, but so far simply that: an awful warning, rather than a dreadful example.

Now European researchers report in Nature Geoscience that they think they have settled the matter. They used evidence from fossils exposed in the Italian Alps to recreate the conditions in the ancient ocean.

“Humanity’s CO2 emission rate is currently fourteen times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth’s history”

The story told by the changing isotopes of carbon, oxygen and most importantly boron in a series of brachiopod fossils was of “substantial” change in the chemistry of sea water 252 million years ago: a change that could be linked to the carbon dioxide from the Siberian Traps eruptions.

The researchers took the reasoning a step further: they used computer models to simulate the conditions of the time. The world warmed, the oceans became increasingly acidic, and right at the outset those organisms in the sea that build shells from calcium were snuffed out of existence.

But the higher temperatures, greater evaporation and ever-higher rainfall that mark a greenhouse world meant ever-greater chemical weathering on land itself. So more nutrients flowed from land to ocean, to deliver too much fertiliser, to encourage too much algal growth.

What followed was a dramatic depletion of dissolved oxygen: marine life was increasingly stifled, or poisoned by sporadic sulphide concentration.

Chain reaction

“We are dealing with a cascading catastrophe in which the rise of CO2 in the atmosphere set off a chain of events that successively extinguished almost all life in the seas,” said Hana Jurikova, then of the Helmholtz Centre for Ocean Research in Kiel, Germany, but now at St Andrew’s in Scotland, who led the study.

It is an axiom of geological research that the present is key to the past, but her forensic account of ancient mayhem may not be a precise lesson for today.

“Ancient volcanic eruptions of this kind are not directly comparable to anthropogenic carbon emissions, and in fact all modern fossil fuel reserves are far too insufficient to release as much CO2 over hundreds of years, let alone thousands of years as was released 252 million years ago,” said Dr Jurikova.

“But it is astonishing that humanity’s CO2 emission rate is currently fourteen times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth’s history”. − Climate News Network

Poor air inflicts billions of premature deaths in Asia

Air pollution by tiny particles is among the world’s worst health risks. In South Asia, poor air is as bad as it gets.

NEW DELHI, 22 October, 2020 − Poor air costs lives, but finding out just how many of them will come as a shock to many residents of South Asia’s big cities.

In India’s capital, New Delhi, just going outside and breathing the air can shorten your life by more than nine years, according to a new report into the region’s air quality that measures the effects of pollution on life expectancy.

For millions of people across across north-west India, Pakistan and Bangladesh, it will be bad news − despite the Covid crisis − because of the current surge in air pollution in the region.

But none of the people of four countries, India, Pakistan, Bangladesh and Nepal, will be happy with the prediction that their lives will be shortened unless their governments take air pollution seriously.

New Delhi is the worst single example in the four, but few of their citizens − a quarter of the world’s population − will escape.

Bangladesh worst hit

Averaged across the whole population, the people of Bangladesh suffer most from air pollution in any country, with their average life span cut short by 6.2 years.

An air quality index (AQI) provides daily air quality assessments, but not the actual health risk. An air quality life index (AQLI) goes further: it converts particulate air pollution into perhaps the most important air pollution metric that exists: its impact on life expectancy.

The report is the work of the Energy Policy Institute at the University of Chicago (EPIC), which has recently updated its AQLI, based on research by its director Michael Greenstone that quantified the causal relationship between human exposure to air pollution and reduced life expectancy.

While the report makes grim reading for nations south of the Himalayas, it does offer some hope, saying that the people of China can see marked improvements since their government began clamping down on polluting industries in 2013.

The report uses two measures to calculate lower expectations of life expectancy: the more stringent World Heath Organisation guidelines (WHO) and the limits imposed by the governments concerned.

“The threat of coronavirus is grave and deserves every bit of the attention it is receiving [but] embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives”

It says air pollution shortens Indian average life expectancy by 5.2 years, relative to what it would be if the WHO guidelines were met, but by 2.3 years relative to the rate if pollution were reduced to meet the country’s own national standard.

Some areas of India fare much worse than the average, with air pollution shortening lives by 9.4 years in Delhi and 8.6 years in the northern state of Uttar Pradesh, the report’s India fact sheet 2020 says.

Similarly, the Pakistan sheet says the average Pakistani’s life expectancy has been shortened by 2.7 years, while air pollution cuts lives by more than 4 years in the most polluted areas.

Naming Bangladesh as the world’s most polluted country, EPIC’s report says air pollution shortens the average citizen’s life expectancy by 6.2 years, compared to what it would be if the WHO guidelines were met.

Again, some areas suffer far more, with lives cut by about 7 years in the most polluted district. In every one of the country’s 64 districts, particulate pollution levels are at least four times the WHO guidelines.

Possible underestimate

Surprisingly Nepal, which unlike its southern neighbours is not normally associated with air pollution, also had serious problems with its crowded and polluted cities. As a result, life expectancy there is cut by 4.7 years across the whole population.

“Though the threat of coronavirus is grave and deserves every bit of the attention it is receiving − perhaps more in some places − embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives,” says Professor Greenstone.

The science of air pollution, and the impact of poor air on the human body, is evolving rapidly, and some Asian scientists have expressed reservations about the accuracy of some of the calculations. However, none of them disputes the fact that millions are dying early because of the pollution.

The report concentrates on the effect of the smaller particulates that are known to do the most damage to lungs, and to enter the bloodstream, and it may in fact be underestimating the overall effects of poor air quality. − Climate News Network

* * * * * *

Nivedita Khandekar is an independent journalist based in New Delhi, covering development and the environment: nivedita_him@rediffmail.com and on twitter at @nivedita_Him

Air pollution by tiny particles is among the world’s worst health risks. In South Asia, poor air is as bad as it gets.

NEW DELHI, 22 October, 2020 − Poor air costs lives, but finding out just how many of them will come as a shock to many residents of South Asia’s big cities.

In India’s capital, New Delhi, just going outside and breathing the air can shorten your life by more than nine years, according to a new report into the region’s air quality that measures the effects of pollution on life expectancy.

For millions of people across across north-west India, Pakistan and Bangladesh, it will be bad news − despite the Covid crisis − because of the current surge in air pollution in the region.

But none of the people of four countries, India, Pakistan, Bangladesh and Nepal, will be happy with the prediction that their lives will be shortened unless their governments take air pollution seriously.

New Delhi is the worst single example in the four, but few of their citizens − a quarter of the world’s population − will escape.

Bangladesh worst hit

Averaged across the whole population, the people of Bangladesh suffer most from air pollution in any country, with their average life span cut short by 6.2 years.

An air quality index (AQI) provides daily air quality assessments, but not the actual health risk. An air quality life index (AQLI) goes further: it converts particulate air pollution into perhaps the most important air pollution metric that exists: its impact on life expectancy.

The report is the work of the Energy Policy Institute at the University of Chicago (EPIC), which has recently updated its AQLI, based on research by its director Michael Greenstone that quantified the causal relationship between human exposure to air pollution and reduced life expectancy.

While the report makes grim reading for nations south of the Himalayas, it does offer some hope, saying that the people of China can see marked improvements since their government began clamping down on polluting industries in 2013.

The report uses two measures to calculate lower expectations of life expectancy: the more stringent World Heath Organisation guidelines (WHO) and the limits imposed by the governments concerned.

“The threat of coronavirus is grave and deserves every bit of the attention it is receiving [but] embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives”

It says air pollution shortens Indian average life expectancy by 5.2 years, relative to what it would be if the WHO guidelines were met, but by 2.3 years relative to the rate if pollution were reduced to meet the country’s own national standard.

Some areas of India fare much worse than the average, with air pollution shortening lives by 9.4 years in Delhi and 8.6 years in the northern state of Uttar Pradesh, the report’s India fact sheet 2020 says.

Similarly, the Pakistan sheet says the average Pakistani’s life expectancy has been shortened by 2.7 years, while air pollution cuts lives by more than 4 years in the most polluted areas.

Naming Bangladesh as the world’s most polluted country, EPIC’s report says air pollution shortens the average citizen’s life expectancy by 6.2 years, compared to what it would be if the WHO guidelines were met.

Again, some areas suffer far more, with lives cut by about 7 years in the most polluted district. In every one of the country’s 64 districts, particulate pollution levels are at least four times the WHO guidelines.

Possible underestimate

Surprisingly Nepal, which unlike its southern neighbours is not normally associated with air pollution, also had serious problems with its crowded and polluted cities. As a result, life expectancy there is cut by 4.7 years across the whole population.

“Though the threat of coronavirus is grave and deserves every bit of the attention it is receiving − perhaps more in some places − embracing the seriousness of air pollution with a similar vigour would allow billions of people around the world to lead longer and healthier lives,” says Professor Greenstone.

The science of air pollution, and the impact of poor air on the human body, is evolving rapidly, and some Asian scientists have expressed reservations about the accuracy of some of the calculations. However, none of them disputes the fact that millions are dying early because of the pollution.

The report concentrates on the effect of the smaller particulates that are known to do the most damage to lungs, and to enter the bloodstream, and it may in fact be underestimating the overall effects of poor air quality. − Climate News Network

* * * * * *

Nivedita Khandekar is an independent journalist based in New Delhi, covering development and the environment: nivedita_him@rediffmail.com and on twitter at @nivedita_Him

China’s climate lead offers the planet new hope

Beijing’s plan to cut greenhouse gases could mean a global expansion of green industries following China’s climate lead.

LONDON, 19 October, 2020 – Whatever mixture of motives lies behind the announcement by President Xi Jinping that his country’s carbon dioxide emissions will peak before 2030, resulting in carbon neutrality before 2060, China’s climate lead offers the prospect of a new era in world affairs.

It alters the face of international negotiations to tackle the climate crisis and boosts hopes that catastrophic global heating can still be avoided.

It is not quite a month since the president took everyone by surprise by making the announcement at the United Nations. Cynics immediately began to question his motives.

Was he trying to corner the vast market in renewables, was he trying to upstage climate-denying and coal-loving President Trump, was he trying to divert attention from internal human rights issues and Hong Kong, or from accusations against China over the Covid crisis? Was he trying re-cast himself as a world leader on environmental matters?

Few seemed generous enough to accept that President Xi was making the announcement because he was genuinely concerned about the effects of climate change on China and the rest of the planet.

Either way, the President’s new targets were certainly a remarkable turnaround. Although there have been more positive statements recently, for more than a decade at successive climate talks China, along with the rest of the developing world, regarded climate change as the developed nations’ problem.

“China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025”

The old industrial countries of the EU, the US and Japan had caused global heating by burning fossil fuels, they argued, so it was up to them to solve the crisis. The immediate job for the developing world’s leaders was to raise their citizens’ living standards, and to worry about their domestic carbon emissions later.

But this was never the whole story. Chinese scientists had long pointed out to its leaders that the country’s future was as bleak as any other nation’s in the world if climate change was not controlled – and quickly.

The major rivers that feed Chinese agriculture will dry up as the glaciers on the Himalayas and the Tibetan plateau disappear; typhoons will regularly threaten the populous south; and the deserts of the north will grow.

And more recently fast-accelerating sea level rise has begun to threaten the economic powerhouse of Shanghai and much of the low-lying coast with inundation.

In addition, since the Beijing Olympics in 2008 it has been clear that air pollution from coal-burning and traffic fumes is a serious economic and health issue in China, while some drastic measures have succeeded in improving air quality.

On 12 October 18 Chinese think tanks combined to put some flesh on the bare bones of President Xi’s bold announcement. In a report published by the Institute of Climate Change and Sustainable Development at Tsinghua University, Beijing, they said immediate carbon cuts were required to keep temperature increases within 1.5°C by 2050.

Globally significant

Reuters news agency reported that a seminar held in Beijing to launch the Institute ’s report was attended by China’s top officials responsible for shaping the country’s energy policy.

One of the report’s contributors, He Jiankun, vice-director of the National Expert Committee on Climate Change, told the meeting: “China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025 and even realise negative growth.

“China is still expected to see the growth of natural gas consumption in 2026-2030, so the growth of carbon emissions from gas use should be offset by the reduction from the coal sector.”

The report also called for China to cut its carbon intensity – the amount of carbon dioxide emissions per GDP unit – by 65% by 2030 from 2015 levels, and to raise non-fossil fuel consumption to 25% by 2030.

This is way above anything that the Chinese government has committed to in the annual UN climate talks and would mean a drastic change in direction, since new coal power stations are still being constructed in large numbers to meet an ever-growing energy demand.

Whatever the motives behind these reduction targets, they matter hugely to the rest of the world. China is currently the world’s largest carbon emitter, with about 29% of the total. This is mainly due to massive coal burning for electricity and for major heavy industries like steel-making, which have moved there from Europe and the US. Switching away from coal would make an immediate difference.

Eye on exports

While critics, particularly climate deniers and right-wing think tanks in the US and Europe, constantly remind the world of Chinese coal-burning habits, they often neglect to mention that the country is a world leader in on-shore wind energy and solar power.

China is also aiming to soon have the largest off-shore wind market, overtaking the United Kingdom.

This might be the key to the President’s thinking. China has a massive domestic demand for renewables, but with wind and solar being the two fastest-growing industries in the world the export market is a great prize.

With President Trump firmly stuck in the fossil fuel age, China has an opportunity to become the lead provider of the technology that many countries in the world need to meet their climate targets.

Depending on who wins the US election on 3 November, President Xi may consolidate his renewables lead at leisure, or be in a race against the Democrat contender, Joe Biden, who has pledged to turn America from a climate laggard to a world leader.

If Biden does win he may find President Xi is already a lap ahead, and hard to overtake. – Climate News Network

Beijing’s plan to cut greenhouse gases could mean a global expansion of green industries following China’s climate lead.

LONDON, 19 October, 2020 – Whatever mixture of motives lies behind the announcement by President Xi Jinping that his country’s carbon dioxide emissions will peak before 2030, resulting in carbon neutrality before 2060, China’s climate lead offers the prospect of a new era in world affairs.

It alters the face of international negotiations to tackle the climate crisis and boosts hopes that catastrophic global heating can still be avoided.

It is not quite a month since the president took everyone by surprise by making the announcement at the United Nations. Cynics immediately began to question his motives.

Was he trying to corner the vast market in renewables, was he trying to upstage climate-denying and coal-loving President Trump, was he trying to divert attention from internal human rights issues and Hong Kong, or from accusations against China over the Covid crisis? Was he trying re-cast himself as a world leader on environmental matters?

Few seemed generous enough to accept that President Xi was making the announcement because he was genuinely concerned about the effects of climate change on China and the rest of the planet.

Either way, the President’s new targets were certainly a remarkable turnaround. Although there have been more positive statements recently, for more than a decade at successive climate talks China, along with the rest of the developing world, regarded climate change as the developed nations’ problem.

“China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025”

The old industrial countries of the EU, the US and Japan had caused global heating by burning fossil fuels, they argued, so it was up to them to solve the crisis. The immediate job for the developing world’s leaders was to raise their citizens’ living standards, and to worry about their domestic carbon emissions later.

But this was never the whole story. Chinese scientists had long pointed out to its leaders that the country’s future was as bleak as any other nation’s in the world if climate change was not controlled – and quickly.

The major rivers that feed Chinese agriculture will dry up as the glaciers on the Himalayas and the Tibetan plateau disappear; typhoons will regularly threaten the populous south; and the deserts of the north will grow.

And more recently fast-accelerating sea level rise has begun to threaten the economic powerhouse of Shanghai and much of the low-lying coast with inundation.

In addition, since the Beijing Olympics in 2008 it has been clear that air pollution from coal-burning and traffic fumes is a serious economic and health issue in China, while some drastic measures have succeeded in improving air quality.

On 12 October 18 Chinese think tanks combined to put some flesh on the bare bones of President Xi’s bold announcement. In a report published by the Institute of Climate Change and Sustainable Development at Tsinghua University, Beijing, they said immediate carbon cuts were required to keep temperature increases within 1.5°C by 2050.

Globally significant

Reuters news agency reported that a seminar held in Beijing to launch the Institute ’s report was attended by China’s top officials responsible for shaping the country’s energy policy.

One of the report’s contributors, He Jiankun, vice-director of the National Expert Committee on Climate Change, told the meeting: “China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025 and even realise negative growth.

“China is still expected to see the growth of natural gas consumption in 2026-2030, so the growth of carbon emissions from gas use should be offset by the reduction from the coal sector.”

The report also called for China to cut its carbon intensity – the amount of carbon dioxide emissions per GDP unit – by 65% by 2030 from 2015 levels, and to raise non-fossil fuel consumption to 25% by 2030.

This is way above anything that the Chinese government has committed to in the annual UN climate talks and would mean a drastic change in direction, since new coal power stations are still being constructed in large numbers to meet an ever-growing energy demand.

Whatever the motives behind these reduction targets, they matter hugely to the rest of the world. China is currently the world’s largest carbon emitter, with about 29% of the total. This is mainly due to massive coal burning for electricity and for major heavy industries like steel-making, which have moved there from Europe and the US. Switching away from coal would make an immediate difference.

Eye on exports

While critics, particularly climate deniers and right-wing think tanks in the US and Europe, constantly remind the world of Chinese coal-burning habits, they often neglect to mention that the country is a world leader in on-shore wind energy and solar power.

China is also aiming to soon have the largest off-shore wind market, overtaking the United Kingdom.

This might be the key to the President’s thinking. China has a massive domestic demand for renewables, but with wind and solar being the two fastest-growing industries in the world the export market is a great prize.

With President Trump firmly stuck in the fossil fuel age, China has an opportunity to become the lead provider of the technology that many countries in the world need to meet their climate targets.

Depending on who wins the US election on 3 November, President Xi may consolidate his renewables lead at leisure, or be in a race against the Democrat contender, Joe Biden, who has pledged to turn America from a climate laggard to a world leader.

If Biden does win he may find President Xi is already a lap ahead, and hard to overtake. – Climate News Network

Drought and heat together menace American West

Climate change really is a burning issue. Simultaneous drought and heat are increasingly likely for more of the American West.

LONDON, 13 October, 2020 − The American West is about to get hotter. It is also about to get drier. To make things worse, extremes of heat and of drought will happen more often at the same time.

And to compound the damage, such simultaneous assaults are likely to extend over larger areas and become more intense and more frequent, thanks to climate change driven by profligate use of fossil fuels and other human decisions.

This is not a prediction based on computer simulations of the future. It is already happening, and the story can be traced − according to the journal Science Advances − in the narrative of hot spells and dry weather over the entire contiguous United States for the last 122 years.

Not only have combined hot and dry episodes increased in frequency, they have also grown in size in geographic terms. Where once they happened in confined localities, they now extend over whole regions, such as the entire West Coast, and parts too of the Northeast and the Southeast.

Another Dust Bowl?

“Dry-hot events can cause large fires. Add wind and a source of ignition, and this results in ‘megafires’ like the 2020 fires across the west coast of the United States. Drought and record-breaking heatwaves, coupled with a storm that brought strong winds and 12,000 lightning events in a span of 72 hours, caused more than 500 wildfires,” said Mohammad Reza Alizadeh, of McGill University in Canada, who led the research.

Heat extremes can be damaging or even devastating. So can drought. When the two coincide, their compound impact can be tragic. The study also suggested that in some way such double jeopardy events could be self-propagating: they could spread downwind, seriously bad news for the American West and other areas at risk.

Long before any fears of the climate emergency, the US Midwest was scarred by drought, and in the 1930s Oklahoma and Kansas in particular became a “Dust Bowl” and inspired the classic novel The Grapes of Wrath by the American writer John Steinbeck.

“We observed that concurrent dry and hot events of similar intensity are becoming more frequent,” said Mojtaba Sadegh, an engineer at Boise State University in Idaho, and the senior author.

“Our results point to an urgent need to take action to enhance resilience to compound hot and dry events”

“The difference is that, in the 1930s, lack of precipitation led to the local atmosphere becoming hotter, whereas in recent decades increased temperatures are driving aridity. The triggering mechanism for compound dry-hot events is changing from lack of precipitation to excess heat.”

The warning of worse to come coincides with news that California’s fires have become so bad that they warrant a new classification: the “gigafire”, with so much smoke emitted from the combined fires of California and Oregon that fumes have been detected in New York, in northern Europe, and far into the Pacific.

Researchers have repeatedly warned of the double hazard of heat and drought and the combined impact on the US, as a consequence of climate change driven by greenhouse gas emissions from power station chimneys and automobile exhausts, as well as destruction of the natural wilderness.

“This research raises an alarm about increasing frequency and intensity of compound hot and dry events,” said Dr Sadegh. “Three such events between 2011-2013 in the US caused $60bn (£46bn) in damages. Our results point to an urgent need to take action to enhance resilience to compound hot and dry events.” − Climate News Network

Climate change really is a burning issue. Simultaneous drought and heat are increasingly likely for more of the American West.

LONDON, 13 October, 2020 − The American West is about to get hotter. It is also about to get drier. To make things worse, extremes of heat and of drought will happen more often at the same time.

And to compound the damage, such simultaneous assaults are likely to extend over larger areas and become more intense and more frequent, thanks to climate change driven by profligate use of fossil fuels and other human decisions.

This is not a prediction based on computer simulations of the future. It is already happening, and the story can be traced − according to the journal Science Advances − in the narrative of hot spells and dry weather over the entire contiguous United States for the last 122 years.

Not only have combined hot and dry episodes increased in frequency, they have also grown in size in geographic terms. Where once they happened in confined localities, they now extend over whole regions, such as the entire West Coast, and parts too of the Northeast and the Southeast.

Another Dust Bowl?

“Dry-hot events can cause large fires. Add wind and a source of ignition, and this results in ‘megafires’ like the 2020 fires across the west coast of the United States. Drought and record-breaking heatwaves, coupled with a storm that brought strong winds and 12,000 lightning events in a span of 72 hours, caused more than 500 wildfires,” said Mohammad Reza Alizadeh, of McGill University in Canada, who led the research.

Heat extremes can be damaging or even devastating. So can drought. When the two coincide, their compound impact can be tragic. The study also suggested that in some way such double jeopardy events could be self-propagating: they could spread downwind, seriously bad news for the American West and other areas at risk.

Long before any fears of the climate emergency, the US Midwest was scarred by drought, and in the 1930s Oklahoma and Kansas in particular became a “Dust Bowl” and inspired the classic novel The Grapes of Wrath by the American writer John Steinbeck.

“We observed that concurrent dry and hot events of similar intensity are becoming more frequent,” said Mojtaba Sadegh, an engineer at Boise State University in Idaho, and the senior author.

“Our results point to an urgent need to take action to enhance resilience to compound hot and dry events”

“The difference is that, in the 1930s, lack of precipitation led to the local atmosphere becoming hotter, whereas in recent decades increased temperatures are driving aridity. The triggering mechanism for compound dry-hot events is changing from lack of precipitation to excess heat.”

The warning of worse to come coincides with news that California’s fires have become so bad that they warrant a new classification: the “gigafire”, with so much smoke emitted from the combined fires of California and Oregon that fumes have been detected in New York, in northern Europe, and far into the Pacific.

Researchers have repeatedly warned of the double hazard of heat and drought and the combined impact on the US, as a consequence of climate change driven by greenhouse gas emissions from power station chimneys and automobile exhausts, as well as destruction of the natural wilderness.

“This research raises an alarm about increasing frequency and intensity of compound hot and dry events,” said Dr Sadegh. “Three such events between 2011-2013 in the US caused $60bn (£46bn) in damages. Our results point to an urgent need to take action to enhance resilience to compound hot and dry events.” − Climate News Network

Hotter seas imperil both human and marine life

Climate warming brings hotter seas. The waters mix less. And conditions for some creatures could grow increasingly stifling.

LONDON, 9 October, 2020 − Climate change has led to hotter seas across the world: in 2018 European water temperatures reached record levels, and a marine heatwave in the north-east Pacific devastated marine life.

Less predictably, global heating has made the oceans more stable, with discrete, stratified layers that resist mixing. And that could be very bad news, because it could make the blue water that covers 70% of the planet less effective at absorbing atmospheric heat and thus mitigating climate change.

And ever-warmer sea temperatures could have another unwelcome impact: as temperatures rise, levels of dissolved oxygen fall. And that could make it difficult for some sea creatures to breathe.

The oceans play a vital role in the water, energy and carbon cycles upon which all life depends. In 2010, demographers counted 1.9 billion people living within 100kms of the sea and less than 100 metres above sea level: that is 28% of all humanity. Many of them are crowded into 17 megacities with populations of more than 5 million people each. For many, the sea is the neighbourhood.

European researchers warn, in a new and detailed report on the state of the oceans from 1993 to 2010, that the rise in sea temperatures in the Mediterranean is without precedent, and the largest rise of all has been measured in the Arctic Ocean.

“Human society has always been dependent on the seas. Failure to reach good environmental status for our seas and oceans is not an option”

They also call as a matter of urgency for comprehensive and systematic monitoring of the ocean. “Human society has always been dependent on the seas,” they warn. “Failure to reach good environmental status for our seas and oceans is not an option.”

Chinese and US scientists report in the journal Nature Climate Change that − beyond reports of stronger winds and waves and ever more intense tropical cyclones − the rise in atmospheric temperatures has fundamentally altered oceanic temperatures and salinity, with a paradoxical effect: the seas have become more stable. Warm and therefore less dense surface water lies upon colder, more saline and denser waters at depth, to limit overall mixing.

Since 1960, the upper 2000 metres of the oceans have become 5% more stratified, and the top 150 metres 18% more stratified.

“The same process, global warming, is both making the atmosphere less stable and the oceans more stable. Water near the ocean’s surface is warming faster than the water below. That makes the oceans become more stable,” said Michael Mann of Penn State University in Pennsylvania, one of the team.

“The ability of the oceans to bury heat from the atmosphere and mitigate global warming is made more difficult when the ocean becomes more stratified and there is less mixing. Less downward mixing of warming waters means the ocean surface warms even faster, leading, for example, to more powerful hurricanes. Global climate models underestimate these trends.”

Struggle for survival

Warmer temperatures don’t just make the oceans more stable, they may make living conditions more uncomfortable or even impossible for some of the sea’s citizenry.

US researchers report in the journal Nature that they looked at the physiological challenge of oxygen and energy demands faced by 145 marine species − including shrimps, catsharks and sea squirts − to find that many are already under pressure.

“Organisms today are living right up to the warmest temperatures possible that will supply them with adequate oxygen for their activity level – so higher temperatures are immediately going to affect their ability to get enough oxygen,” said Curtis Deutsch of the University of Washington.

“In response to warming, their activity level is going to be restricted or their habitat is going to start shrinking. It’s not like they are going to be fine and carry on.” − Climate News Network

Climate warming brings hotter seas. The waters mix less. And conditions for some creatures could grow increasingly stifling.

LONDON, 9 October, 2020 − Climate change has led to hotter seas across the world: in 2018 European water temperatures reached record levels, and a marine heatwave in the north-east Pacific devastated marine life.

Less predictably, global heating has made the oceans more stable, with discrete, stratified layers that resist mixing. And that could be very bad news, because it could make the blue water that covers 70% of the planet less effective at absorbing atmospheric heat and thus mitigating climate change.

And ever-warmer sea temperatures could have another unwelcome impact: as temperatures rise, levels of dissolved oxygen fall. And that could make it difficult for some sea creatures to breathe.

The oceans play a vital role in the water, energy and carbon cycles upon which all life depends. In 2010, demographers counted 1.9 billion people living within 100kms of the sea and less than 100 metres above sea level: that is 28% of all humanity. Many of them are crowded into 17 megacities with populations of more than 5 million people each. For many, the sea is the neighbourhood.

European researchers warn, in a new and detailed report on the state of the oceans from 1993 to 2010, that the rise in sea temperatures in the Mediterranean is without precedent, and the largest rise of all has been measured in the Arctic Ocean.

“Human society has always been dependent on the seas. Failure to reach good environmental status for our seas and oceans is not an option”

They also call as a matter of urgency for comprehensive and systematic monitoring of the ocean. “Human society has always been dependent on the seas,” they warn. “Failure to reach good environmental status for our seas and oceans is not an option.”

Chinese and US scientists report in the journal Nature Climate Change that − beyond reports of stronger winds and waves and ever more intense tropical cyclones − the rise in atmospheric temperatures has fundamentally altered oceanic temperatures and salinity, with a paradoxical effect: the seas have become more stable. Warm and therefore less dense surface water lies upon colder, more saline and denser waters at depth, to limit overall mixing.

Since 1960, the upper 2000 metres of the oceans have become 5% more stratified, and the top 150 metres 18% more stratified.

“The same process, global warming, is both making the atmosphere less stable and the oceans more stable. Water near the ocean’s surface is warming faster than the water below. That makes the oceans become more stable,” said Michael Mann of Penn State University in Pennsylvania, one of the team.

“The ability of the oceans to bury heat from the atmosphere and mitigate global warming is made more difficult when the ocean becomes more stratified and there is less mixing. Less downward mixing of warming waters means the ocean surface warms even faster, leading, for example, to more powerful hurricanes. Global climate models underestimate these trends.”

Struggle for survival

Warmer temperatures don’t just make the oceans more stable, they may make living conditions more uncomfortable or even impossible for some of the sea’s citizenry.

US researchers report in the journal Nature that they looked at the physiological challenge of oxygen and energy demands faced by 145 marine species − including shrimps, catsharks and sea squirts − to find that many are already under pressure.

“Organisms today are living right up to the warmest temperatures possible that will supply them with adequate oxygen for their activity level – so higher temperatures are immediately going to affect their ability to get enough oxygen,” said Curtis Deutsch of the University of Washington.

“In response to warming, their activity level is going to be restricted or their habitat is going to start shrinking. It’s not like they are going to be fine and carry on.” − Climate News Network

River deltas become even riskier as climate warms

River deltas are among the world’s richest habitats. They are also, increasingly, home to the most vulnerable people.

LONDON, 8 October, 2020 − Already, more than 30 million people worldwide are in danger of catastrophic floods − and now they face further danger from the river deltas which are their homes.

Ocean storm surges which are one threat could wash away their homes, their livelihoods, and even their lives. Another, rising tide levels, could turn their gardens to salt and sap the foundations of their lives. With many more, tropical cyclones could sweep in and literally rain their houses into the sea

What all these vulnerable people − in New Orleans, in Bangkok, in Shanghai, in the mouths of the Ganges-Brahmaputra, in any of more than 2,000 settlements − have in common is that they live on a river delta: that vital, ever-shifting zone where a great river spills its silt into the ocean.

And climate change driven by ever-rising ratios of greenhouse gases in the atmosphere − a consequence of ever-greater reliance on fossil fuels − can only make such hazards ever more dangerous. But the first challenge is: who, exactly, is most at risk? And where?

“To date, no-one has successfully quantified the global population in river deltas and assessed the cumulative impacts from climate change,” said Douglas Edmonds, of the University of Indiana in the US.

Costly endowment

“Since river deltas have long been recognised as hotspots of population growth, and with increasing impacts from climate change, we realised we needed to properly quantify what the cumulative risks are in river deltas.”

Dr Edmonds and his colleagues report in Nature Communications that they assembled a global database of 2,174 delta locations, to identity the populations settled on and around them in 2017, and the topography most at risk.

River deltas add up to perhaps 0.5% of the planet’s land surface, but they are home to 4.5% of the world’s population. Humans have settled on river deltas for at least 7,000 years: the rivers deliver nutrient-rich silts for new farmland, and the river estuaries have provided a focus for regional and international transport, to become some of the world’s greatest cities.

But such riches come at a cost: as the rivers have been contained and engineered, the land cover has changed and the land surface subsided. So as sea levels rise with climate change, deltaic areas could become 50% more vulnerable to coastal flood.

“No-one has successfully quantified the global population in river deltas and assessed the cumulative impacts from climate change”

Precisely because river deltas form at or even below sea level, they are highly prone to storm surges driven by tropical cyclones. And by 2100, these could become from 2% to 11% more intense.

The researchers found that in 2017, around 339m people had made their homes on 710,000 square kilometres of habitable land around river deltas: in this century alone, the population on deltas had grown by 34%.

Of these, 31m lived on floodplains vulnerable to the kind of storm surges that happen once a century. And of this 31m, 92% lived in developing or least-developed economies, often breathing polluted air, with poor housing and limited access to public services such as drainage. So, as usual, the poorest were also the most at risk from climate change.

In fact, as scientists have been warning for a decade or more, coastal flooding is a hazard inevitably on the increase, and an increasingly costly one, worldwide.

Even in the US, floods will become a serial nuisance in many cities and an estimated 13m Americans could eventually become climate refugees.

Very cautious estimates

Climate change is likely to deliver a hotter, wetter world with more soil erosion that could trigger catastrophic delta flooding. Hurricanes and typhoons driven by rising sea temperatures are likely to exact an ever-greater toll on human life and wealth.

The Indiana scientists warn that their estimates of those most at risk and the costs they face are likely to be highly conservative. They did not, for instance, consider the special case of what they call “compound interaction.”

This is sociological shorthand for what could happen when climate-related disaster overtakes those who are poorest, crowded into the least protected and unhealthiest zones of the cities. Altogether, 105m people have settled on the Ganges-Brahmaputra delta, half of them on low-lying farmland. The second most crowded is the Nile delta, with 45m people.

“To effectively prepare for more intense future coastal flooding,” Dr Edmonds said, “we need to reframe it as a problem that disproportionately impacts people on river deltas in developing and least developed economies.” − Climate News Network

River deltas are among the world’s richest habitats. They are also, increasingly, home to the most vulnerable people.

LONDON, 8 October, 2020 − Already, more than 30 million people worldwide are in danger of catastrophic floods − and now they face further danger from the river deltas which are their homes.

Ocean storm surges which are one threat could wash away their homes, their livelihoods, and even their lives. Another, rising tide levels, could turn their gardens to salt and sap the foundations of their lives. With many more, tropical cyclones could sweep in and literally rain their houses into the sea

What all these vulnerable people − in New Orleans, in Bangkok, in Shanghai, in the mouths of the Ganges-Brahmaputra, in any of more than 2,000 settlements − have in common is that they live on a river delta: that vital, ever-shifting zone where a great river spills its silt into the ocean.

And climate change driven by ever-rising ratios of greenhouse gases in the atmosphere − a consequence of ever-greater reliance on fossil fuels − can only make such hazards ever more dangerous. But the first challenge is: who, exactly, is most at risk? And where?

“To date, no-one has successfully quantified the global population in river deltas and assessed the cumulative impacts from climate change,” said Douglas Edmonds, of the University of Indiana in the US.

Costly endowment

“Since river deltas have long been recognised as hotspots of population growth, and with increasing impacts from climate change, we realised we needed to properly quantify what the cumulative risks are in river deltas.”

Dr Edmonds and his colleagues report in Nature Communications that they assembled a global database of 2,174 delta locations, to identity the populations settled on and around them in 2017, and the topography most at risk.

River deltas add up to perhaps 0.5% of the planet’s land surface, but they are home to 4.5% of the world’s population. Humans have settled on river deltas for at least 7,000 years: the rivers deliver nutrient-rich silts for new farmland, and the river estuaries have provided a focus for regional and international transport, to become some of the world’s greatest cities.

But such riches come at a cost: as the rivers have been contained and engineered, the land cover has changed and the land surface subsided. So as sea levels rise with climate change, deltaic areas could become 50% more vulnerable to coastal flood.

“No-one has successfully quantified the global population in river deltas and assessed the cumulative impacts from climate change”

Precisely because river deltas form at or even below sea level, they are highly prone to storm surges driven by tropical cyclones. And by 2100, these could become from 2% to 11% more intense.

The researchers found that in 2017, around 339m people had made their homes on 710,000 square kilometres of habitable land around river deltas: in this century alone, the population on deltas had grown by 34%.

Of these, 31m lived on floodplains vulnerable to the kind of storm surges that happen once a century. And of this 31m, 92% lived in developing or least-developed economies, often breathing polluted air, with poor housing and limited access to public services such as drainage. So, as usual, the poorest were also the most at risk from climate change.

In fact, as scientists have been warning for a decade or more, coastal flooding is a hazard inevitably on the increase, and an increasingly costly one, worldwide.

Even in the US, floods will become a serial nuisance in many cities and an estimated 13m Americans could eventually become climate refugees.

Very cautious estimates

Climate change is likely to deliver a hotter, wetter world with more soil erosion that could trigger catastrophic delta flooding. Hurricanes and typhoons driven by rising sea temperatures are likely to exact an ever-greater toll on human life and wealth.

The Indiana scientists warn that their estimates of those most at risk and the costs they face are likely to be highly conservative. They did not, for instance, consider the special case of what they call “compound interaction.”

This is sociological shorthand for what could happen when climate-related disaster overtakes those who are poorest, crowded into the least protected and unhealthiest zones of the cities. Altogether, 105m people have settled on the Ganges-Brahmaputra delta, half of them on low-lying farmland. The second most crowded is the Nile delta, with 45m people.

“To effectively prepare for more intense future coastal flooding,” Dr Edmonds said, “we need to reframe it as a problem that disproportionately impacts people on river deltas in developing and least developed economies.” − Climate News Network

Antarctica’s ice loss could soon be irreversible

Global heating means the southern ice will melt. Antarctica’s ice loss could then be permanent, drowning many great cities.

LONDON, 2 October, 2020 – The greatest mass of ice on the planet is growing steadily more unstable, and that means Antarctica’s ice loss may before long be inexorable.

New studies show that right now, just one degree of warming must mean an eventual sea level rise of 1.3 metres, simply from the flow of melting ice from the continent of Antarctica.

If the annual average temperature of the planet goes beyond 2°C, then the Antarctic melting rate will double. And when global heating really steps up to 6°C or beyond, melting accelerates to the almost unimaginable level of 10 metres for every single degree rise in planetary average temperatures.

And, the researchers say, there is no way back. Even if the world’s nations stick to a promise made in Paris in 2015, to keep global heating to “well below” 2°C by the end of the century, the losses of the southern polar ice sheet cannot be restored: the process of melting, once triggered by global temperature rise, becomes inexorable.

European and US researchers report in the journal Nature that they worked through ice core records of long-ago change in Antarctica and employed a million hours of computer simulation time to build up a reliable picture of change on the Antarctic continent, in response to ever-higher planetary average temperatures, driven by ever more profligate use of fossil fuels to generate ever-higher atmospheric ratios of greenhouse gases.

Their word for the state they wanted to study is hysteresis: this can be interpreted as the way altered conditions might commit a state to further change.

“If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York”

The planet’s climate has oscillated many times over many millions of years. What this climate shift does to the polar regions can literally change the map of the planet. Antarctica is an enormous continent, the size of the US, Mexico and India together, and the ice it bears would, if it all were to melt, raise global sea levels by 58 metres.

“Antarctica holds more than half of Earth’s fresh water, frozen in a vast ice-sheet which is nearly five kilometres thick. As the surrounding ocean water and atmosphere warm due to human greenhouse gas emissions, the white cap on the South Pole loses mass and eventually becomes unstable,” said Ricarda Winkelmann, of the Potsdam Institute for Climate Impact Research.

“Because of its sheer magnitude, Antarctica’s potential for sea level contribution is enormous. We find that already at two degrees of warming, melting and the accelerated ice flow into the ocean will, eventually, entail 2.5 metres of global sea level rise just from Antarctica alone. At four degrees, it will be 6.5 metres and at six degrees almost 12 metres, if these temperature levels would be sustained long enough.”

That loss of ice would be slow – it would take many thousands of years – but the point the researchers make is that the continent may already be nearing a tipping point, after which the slide towards ever-higher sea levels would be unstoppable.

Since the great ice sheets of Greenland and Antarctica are part of the planetary cooling system – their whiteness reflects solar radiation back into space, so that the ice becomes its own insulation – their loss would inevitably trigger the process of further and faster warming.

Scientists from all nations have been warning for more than a decade that the continent is losing its protective screen of seaborne shelf ice, which in turn would make glacier flow towards the sea ever faster, and that the rate of loss of ice has begun to accelerate.

No going back

“In the end, it is our burning of coal and oil that determines ongoing and future greenhouse gas emissions and, therefore, if and when critical temperature thresholds in Antarctica are crossed.

“And even if the ice loss happens on long time scales, the respective carbon dioxide levels can already be reached in the near future,” said Professor Winkelmann.

“We decide now whether we manage to halt the warming. So Antarctica’s fate really lies in our hands – and with it that of our cities and cultural sites across the globe, from Rio de Janeiro’s Copacabana to Sydney’s Opera House. Thus this study really is another exclamation mark behind the importance of the Paris Climate Accord: Keep global warming below two degrees.”

And her Potsdam co-author Anders Levermann reinforced the argument. “Our simulations show that once it’s melted, it does not regrow to its initial state even if temperatures eventually sank again.

“Indeed, temperatures would have to go back to pre-industrial levels to allow its full recovery – a highly unlikely scenario. In other words: what we lose of Antarctica now is lost forever.”

And he warned: “If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York.” – Climate News Network

Global heating means the southern ice will melt. Antarctica’s ice loss could then be permanent, drowning many great cities.

LONDON, 2 October, 2020 – The greatest mass of ice on the planet is growing steadily more unstable, and that means Antarctica’s ice loss may before long be inexorable.

New studies show that right now, just one degree of warming must mean an eventual sea level rise of 1.3 metres, simply from the flow of melting ice from the continent of Antarctica.

If the annual average temperature of the planet goes beyond 2°C, then the Antarctic melting rate will double. And when global heating really steps up to 6°C or beyond, melting accelerates to the almost unimaginable level of 10 metres for every single degree rise in planetary average temperatures.

And, the researchers say, there is no way back. Even if the world’s nations stick to a promise made in Paris in 2015, to keep global heating to “well below” 2°C by the end of the century, the losses of the southern polar ice sheet cannot be restored: the process of melting, once triggered by global temperature rise, becomes inexorable.

European and US researchers report in the journal Nature that they worked through ice core records of long-ago change in Antarctica and employed a million hours of computer simulation time to build up a reliable picture of change on the Antarctic continent, in response to ever-higher planetary average temperatures, driven by ever more profligate use of fossil fuels to generate ever-higher atmospheric ratios of greenhouse gases.

Their word for the state they wanted to study is hysteresis: this can be interpreted as the way altered conditions might commit a state to further change.

“If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York”

The planet’s climate has oscillated many times over many millions of years. What this climate shift does to the polar regions can literally change the map of the planet. Antarctica is an enormous continent, the size of the US, Mexico and India together, and the ice it bears would, if it all were to melt, raise global sea levels by 58 metres.

“Antarctica holds more than half of Earth’s fresh water, frozen in a vast ice-sheet which is nearly five kilometres thick. As the surrounding ocean water and atmosphere warm due to human greenhouse gas emissions, the white cap on the South Pole loses mass and eventually becomes unstable,” said Ricarda Winkelmann, of the Potsdam Institute for Climate Impact Research.

“Because of its sheer magnitude, Antarctica’s potential for sea level contribution is enormous. We find that already at two degrees of warming, melting and the accelerated ice flow into the ocean will, eventually, entail 2.5 metres of global sea level rise just from Antarctica alone. At four degrees, it will be 6.5 metres and at six degrees almost 12 metres, if these temperature levels would be sustained long enough.”

That loss of ice would be slow – it would take many thousands of years – but the point the researchers make is that the continent may already be nearing a tipping point, after which the slide towards ever-higher sea levels would be unstoppable.

Since the great ice sheets of Greenland and Antarctica are part of the planetary cooling system – their whiteness reflects solar radiation back into space, so that the ice becomes its own insulation – their loss would inevitably trigger the process of further and faster warming.

Scientists from all nations have been warning for more than a decade that the continent is losing its protective screen of seaborne shelf ice, which in turn would make glacier flow towards the sea ever faster, and that the rate of loss of ice has begun to accelerate.

No going back

“In the end, it is our burning of coal and oil that determines ongoing and future greenhouse gas emissions and, therefore, if and when critical temperature thresholds in Antarctica are crossed.

“And even if the ice loss happens on long time scales, the respective carbon dioxide levels can already be reached in the near future,” said Professor Winkelmann.

“We decide now whether we manage to halt the warming. So Antarctica’s fate really lies in our hands – and with it that of our cities and cultural sites across the globe, from Rio de Janeiro’s Copacabana to Sydney’s Opera House. Thus this study really is another exclamation mark behind the importance of the Paris Climate Accord: Keep global warming below two degrees.”

And her Potsdam co-author Anders Levermann reinforced the argument. “Our simulations show that once it’s melted, it does not regrow to its initial state even if temperatures eventually sank again.

“Indeed, temperatures would have to go back to pre-industrial levels to allow its full recovery – a highly unlikely scenario. In other words: what we lose of Antarctica now is lost forever.”

And he warned: “If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York.” – Climate News Network

Supply chains generate massive carbon emissions

When it comes to cutting carbon emissions, think global. Think multinational. Think Coca-Cola, or Total. But don’t fly.

LONDON, 25 September, 2020 – Chinese and European researchers have identified the source of almost one-fifth of all the world’s carbon emissions. They come from the supply chains of giant multinational companies.

Not only does global business export investment, it exports carbon dioxide emissions as well. And the big players play it really big.

The US business Walmart, the world’s biggest retailer, with 11,500 stores in 28 countries, in 2016 generated more emissions abroad than the whole of Germany’s foreign-owned retail sector.

That year Coca-Cola’s global emissions matched those from the entire foreign food-and-drink industry in China. Total SA’s foreign affiliates generated more than a tenth of the total emissions of France. Altogether, the multinational giants accounted for 18.7% of global emissions.

By contrast, and to provide perspective, the entire global aviation industry contributes just 3.5% of the forces that drive climate change – and that includes the impact of condensation trails and soot and sulphur exhausts as well as carbon dioxide emissions.

“If the world’s leading companies exercised leadership on climate change they could have a transformative effect on global efforts to reduce emissions”

In fact, in eight decades, the aviation industry’s total carbon dioxide discharges add up to only 1.5% of all humankind’s total carbon emissions up to 2018, according to British researchers.

These two very different studies illuminate the great challenge of climate change: it’s not enough for a country to claim it has reduced its carbon footprint, if its big achievement has been to export the burden of emissions to a labour force somewhere else.

And it’s not enough to measure just carbon dioxide. Tomorrow’s planners, investors, economists, designers and engineers must also think about the whole package of anthropogenic change that has begun to raise the planetary temperature to dangerous levels. And in each case the message is the same: think of it as a transnational challenge.

“Multinational companies have enormous influence stretching far beyond national borders,” said Dabo Guan of University College London. “If the world’s leading companies exercised leadership on climate change – for instance by requiring energy efficiency in their supply chains – they could have a transformative effect on global efforts to reduce emissions.”

Outsourced responsibility

Professor Guan and colleagues from Beijing and Norway report in the journal Nature Climate Change that they looked for a new way to measure the impact of big business.

They followed the money. They found that when investment flowed from developed to developing countries, those businesses were also outsourcing the responsibility for carbon emissions. So a fair way of accounting carbon responsibility would be to return it to the investor nation.

For example in 2011, US investment in India resulted in emissions of more than 43 million tonnes. By 2016, this figure had passed more than 70 million tonnes. In 2011, emissions from multinational investment stood at 22% of all emissions worldwide. By 2016 this figure had fallen to 18.7% – partly because of improvements in energy efficiency, and partly because of a fall in foreign investment.

Although carbon dioxide emissions have become a standard measure for potential climate change, they are only part of the story. The climate damage from a jet flight is more than just the greenhouse gas from burning high-octane fuel.

New analysis in the journal Atmospheric Environment confirms that aviation’s biggest contribution to global warming is the effects on clouds: cirrus condensation trails formed by the almost-explosive growth in air traffic reflect and trap heat escaping from the atmosphere on a massive scale.

International flights exempted

The discharge of water vapour, soot and sulphate particles from the engines is also part of what the researchers call “effective radiative forcing,” or ERF.

And when these aspects are factored in, it seems that aviation on a global scale adds up to 3.5% of all human activities that drive climate change. The Paris Agreement on climate change – a global resolve to contain global heating by 2100 to “well below” 2°C above the norm for most of human history – includes domestic aviation within national targets to reduce emissions.

But it does not address international aviation, which adds up to 64% of all air traffic.

“The new study means that aviation’s impact on climate change can be compared with other sectors such as maritime shipping, ground transportation and energy generation, as it has a consistent set of ERF measurements,” said David Lee, of Manchester Metropolitan University, who led the research. – Climate News Network

When it comes to cutting carbon emissions, think global. Think multinational. Think Coca-Cola, or Total. But don’t fly.

LONDON, 25 September, 2020 – Chinese and European researchers have identified the source of almost one-fifth of all the world’s carbon emissions. They come from the supply chains of giant multinational companies.

Not only does global business export investment, it exports carbon dioxide emissions as well. And the big players play it really big.

The US business Walmart, the world’s biggest retailer, with 11,500 stores in 28 countries, in 2016 generated more emissions abroad than the whole of Germany’s foreign-owned retail sector.

That year Coca-Cola’s global emissions matched those from the entire foreign food-and-drink industry in China. Total SA’s foreign affiliates generated more than a tenth of the total emissions of France. Altogether, the multinational giants accounted for 18.7% of global emissions.

By contrast, and to provide perspective, the entire global aviation industry contributes just 3.5% of the forces that drive climate change – and that includes the impact of condensation trails and soot and sulphur exhausts as well as carbon dioxide emissions.

“If the world’s leading companies exercised leadership on climate change they could have a transformative effect on global efforts to reduce emissions”

In fact, in eight decades, the aviation industry’s total carbon dioxide discharges add up to only 1.5% of all humankind’s total carbon emissions up to 2018, according to British researchers.

These two very different studies illuminate the great challenge of climate change: it’s not enough for a country to claim it has reduced its carbon footprint, if its big achievement has been to export the burden of emissions to a labour force somewhere else.

And it’s not enough to measure just carbon dioxide. Tomorrow’s planners, investors, economists, designers and engineers must also think about the whole package of anthropogenic change that has begun to raise the planetary temperature to dangerous levels. And in each case the message is the same: think of it as a transnational challenge.

“Multinational companies have enormous influence stretching far beyond national borders,” said Dabo Guan of University College London. “If the world’s leading companies exercised leadership on climate change – for instance by requiring energy efficiency in their supply chains – they could have a transformative effect on global efforts to reduce emissions.”

Outsourced responsibility

Professor Guan and colleagues from Beijing and Norway report in the journal Nature Climate Change that they looked for a new way to measure the impact of big business.

They followed the money. They found that when investment flowed from developed to developing countries, those businesses were also outsourcing the responsibility for carbon emissions. So a fair way of accounting carbon responsibility would be to return it to the investor nation.

For example in 2011, US investment in India resulted in emissions of more than 43 million tonnes. By 2016, this figure had passed more than 70 million tonnes. In 2011, emissions from multinational investment stood at 22% of all emissions worldwide. By 2016 this figure had fallen to 18.7% – partly because of improvements in energy efficiency, and partly because of a fall in foreign investment.

Although carbon dioxide emissions have become a standard measure for potential climate change, they are only part of the story. The climate damage from a jet flight is more than just the greenhouse gas from burning high-octane fuel.

New analysis in the journal Atmospheric Environment confirms that aviation’s biggest contribution to global warming is the effects on clouds: cirrus condensation trails formed by the almost-explosive growth in air traffic reflect and trap heat escaping from the atmosphere on a massive scale.

International flights exempted

The discharge of water vapour, soot and sulphate particles from the engines is also part of what the researchers call “effective radiative forcing,” or ERF.

And when these aspects are factored in, it seems that aviation on a global scale adds up to 3.5% of all human activities that drive climate change. The Paris Agreement on climate change – a global resolve to contain global heating by 2100 to “well below” 2°C above the norm for most of human history – includes domestic aviation within national targets to reduce emissions.

But it does not address international aviation, which adds up to 64% of all air traffic.

“The new study means that aviation’s impact on climate change can be compared with other sectors such as maritime shipping, ground transportation and energy generation, as it has a consistent set of ERF measurements,” said David Lee, of Manchester Metropolitan University, who led the research. – Climate News Network

Melting Arctic needs new name to match reality

Change in the far north is happening so fast that soon the melting Arctic won’t be arctic any more.

LONDON, 16 September, 2020 − The word Arctic may be up for redefinition. The conditions within the melting Arctic Circle are changing so fast that what was once a frozen seascape could now be entering a new climate regime in which nothing is predictable.

Even in an unusually cold year, the sea ice may not return to the summer limits normal in the last century. For some months of autumn and even winter, rain will fall instead of snow, US scientists report in the journal Nature Climate Change.

“The rate of change is remarkable,” said Laura Landrum, of the US National Centre for Atmospheric Research, who led the study.

“It’s a period of such rapid change that observations of past weather patterns no longer show what you can expect next year. The Arctic is already entering a completely different climate than just a few decades ago.”

She and a colleague looked at four decades of satellite data and ground observations and hundreds of computer simulations to confirm that polar warming is happening at such a rate that any change year to year is no longer within the extremes of the past. Conditions that were once normally changeable are now abnormally so.

“The Arctic is already entering a completely different climate than just a few decades ago … We need to change our definition of what the Arctic is”

Climate in the northern hemisphere is moderated by temperature differences that vary with latitude: between them, a torrid equator and a frozen Arctic drive the prevailing winds and ocean currents and the mix of cloud, sunshine, rainfall, frost, windstorm, dry spells and seasonal flooding in which agriculture, industry and civilisation have evolved for the last 10,000 years.

But as carbon dioxide levels in the atmosphere soar in response to rapidly-increasing use of fossil fuels, the melting Arctic has been warming far more swiftly than the planet as a whole.

The extent of summer sea ice in each of the last 13 years has been lower than any minimum observed since 1979, when systematic observation began. Winters have been warmer, winter sea ice has been reduced, rain has been falling on snow ever earlier.

The climate scientists posed themselves the simple question: “While these changes appear extreme compared with the recent past, are they climate extremes in a statistical sense, or do they represent expected events in a new Arctic climate?”

New climate develops

The answer seems to be: yes. The researchers tested their statistical techniques on five different climate simulations. Each of these showed the sea ice retreating so dramatically that a new climate had emerged some time in the late 20th and early 21st centuries.

The finding fits a pattern of foreboding delivered by recent research. In the last two months, researchers have warned that ice loss in the Arctic regions has been so severe that the region’s most charismatic predator, the polar bear, may be gone by the century’s end.

Another group has warned that the Arctic ocean in late summer may be effectively ice-free within the next 15 years.

One group has concluded that ice loss from Greenland is now at such a rate as to be irreversible, and another has confirmed that the rate of ice melt from the northern hemisphere’s biggest reserve – enough to raise sea levels six or seven metres – last year reached new records.

And this month an international research team reported that the rate of change in the Arctic has exceeded the “worst-case” scenario proposed by climate researchers.

Unknown extremes ahead

Dr Landrum and her colleague report that − if greenhouse gas emissions continue at their present rate − some of their climate forecasts predict a mostly ice-free Arctic for between three and 10 months a year, every year, by the end of the century.

Air temperatures over the ocean in autumn and winter will become warmer before or by mid-century, and then start warming over land in the second half.

In a warmer world, more water will evaporate and fall again as rain. Over Alaska, northern Canada and northern Siberia there will be more rain rather than snow: by mid-century, perhaps an extra 20 to 60 days, and by 2100, perhaps from 60 to an extra 90 days. In some parts of the Arctic, by the century’s end, rain might fall in any month of the year.

“The Arctic is likely to experience extremes in sea ice, temperature and precipitation that are far outside anything we’ve experienced before,” Dr Landrum said. “We need to change our definition of what the Arctic is.” − Climate News Network

Change in the far north is happening so fast that soon the melting Arctic won’t be arctic any more.

LONDON, 16 September, 2020 − The word Arctic may be up for redefinition. The conditions within the melting Arctic Circle are changing so fast that what was once a frozen seascape could now be entering a new climate regime in which nothing is predictable.

Even in an unusually cold year, the sea ice may not return to the summer limits normal in the last century. For some months of autumn and even winter, rain will fall instead of snow, US scientists report in the journal Nature Climate Change.

“The rate of change is remarkable,” said Laura Landrum, of the US National Centre for Atmospheric Research, who led the study.

“It’s a period of such rapid change that observations of past weather patterns no longer show what you can expect next year. The Arctic is already entering a completely different climate than just a few decades ago.”

She and a colleague looked at four decades of satellite data and ground observations and hundreds of computer simulations to confirm that polar warming is happening at such a rate that any change year to year is no longer within the extremes of the past. Conditions that were once normally changeable are now abnormally so.

“The Arctic is already entering a completely different climate than just a few decades ago … We need to change our definition of what the Arctic is”

Climate in the northern hemisphere is moderated by temperature differences that vary with latitude: between them, a torrid equator and a frozen Arctic drive the prevailing winds and ocean currents and the mix of cloud, sunshine, rainfall, frost, windstorm, dry spells and seasonal flooding in which agriculture, industry and civilisation have evolved for the last 10,000 years.

But as carbon dioxide levels in the atmosphere soar in response to rapidly-increasing use of fossil fuels, the melting Arctic has been warming far more swiftly than the planet as a whole.

The extent of summer sea ice in each of the last 13 years has been lower than any minimum observed since 1979, when systematic observation began. Winters have been warmer, winter sea ice has been reduced, rain has been falling on snow ever earlier.

The climate scientists posed themselves the simple question: “While these changes appear extreme compared with the recent past, are they climate extremes in a statistical sense, or do they represent expected events in a new Arctic climate?”

New climate develops

The answer seems to be: yes. The researchers tested their statistical techniques on five different climate simulations. Each of these showed the sea ice retreating so dramatically that a new climate had emerged some time in the late 20th and early 21st centuries.

The finding fits a pattern of foreboding delivered by recent research. In the last two months, researchers have warned that ice loss in the Arctic regions has been so severe that the region’s most charismatic predator, the polar bear, may be gone by the century’s end.

Another group has warned that the Arctic ocean in late summer may be effectively ice-free within the next 15 years.

One group has concluded that ice loss from Greenland is now at such a rate as to be irreversible, and another has confirmed that the rate of ice melt from the northern hemisphere’s biggest reserve – enough to raise sea levels six or seven metres – last year reached new records.

And this month an international research team reported that the rate of change in the Arctic has exceeded the “worst-case” scenario proposed by climate researchers.

Unknown extremes ahead

Dr Landrum and her colleague report that − if greenhouse gas emissions continue at their present rate − some of their climate forecasts predict a mostly ice-free Arctic for between three and 10 months a year, every year, by the end of the century.

Air temperatures over the ocean in autumn and winter will become warmer before or by mid-century, and then start warming over land in the second half.

In a warmer world, more water will evaporate and fall again as rain. Over Alaska, northern Canada and northern Siberia there will be more rain rather than snow: by mid-century, perhaps an extra 20 to 60 days, and by 2100, perhaps from 60 to an extra 90 days. In some parts of the Arctic, by the century’s end, rain might fall in any month of the year.

“The Arctic is likely to experience extremes in sea ice, temperature and precipitation that are far outside anything we’ve experienced before,” Dr Landrum said. “We need to change our definition of what the Arctic is.” − Climate News Network

Mass migration set to increase as world warms

Climate change is now driving mass migration, which will only worsen unless governments take global heating seriously.

LONDON, 15 September, 2020 −There is strong evidence that deteriorating environments caused by climate change are driving millions of people to resort to mass migration in their search for a better life, both within countries and across borders.

As temperatures rise these migrations will only increase, particularly in Latin America and India, which is predicted to overtake China as the country with the largest population by 2025.

An analysis of environment and migration, published in Nature Climate Change, of 30 studies of individual countries across the world shows that there is no one single factor that drives migration.

But most research has found that environmental hazards have a major influence. Rising temperature levels, changes in rainfall and single sudden events like hurricanes are all triggers.

Policies for improvement

The analysis, by the International Institute for Applied Systems Analysis (IIASA) in Austria and research partners across Europe, was undertaken to try to inform policy makers about how to avert mass human migration.

It points out that two of the most high-profile mass migration episodes in recent times – the Syrian refugee crisis in 2015 and the “migrant caravan” from Central America to the United States in 2018 – have been partly attributed to severe droughts in the countries concerned.

While some studies conclude that environmental factors were not the main driver of migration, most thought it was one of the primary causes. The analysis says governments should expect significantly higher migration flows in the future.

Perhaps surprisingly, given the publicity surrounding the issue, migrations were not centred on poor people trying to enter rich nations in Europe or North America. Instead, most movements were from the countryside to urban areas in the same country, particularly in agriculturally dependent countries, or from one middle-income country to another.

“The best way to protect those affected is to stabilise the global climate by rapidly reducing greenhouse gas emissions from burning fossil fuels”

People with particularly low incomes normally stayed where they were,  despite environmental pressures, because they had no way of financing a move, while richer people had the means to adapt to new circumstances and so they also stayed put.

“Environmental factors can drive migration, but the size of the effects depends on the particular economic and socio-political conditions in the countries,” explains the lead author Roman Hoffmann, from Germany’s Potsdam Institute for Climate Impact Research (PIK).

“In both low and high income countries, environmental impacts on migration are weaker – presumably because either people are too poor to leave and therefore essentially become trapped or, in wealthy countries, they have enough financial means to absorb the consequences. It is mainly in middle-income regions and those with a dependency on agriculture that we see strong effects.”

IIASA predicts future higher levels of environmental migration for countries in Central America, the Caribbean, Brazil and Argentina. In Africa it is the Sahel region south of the Sahara that is already drying out, and East Africa that has the highest potential for people migrating because of climate change.

Eyes on India

Perhaps the most disturbing prediction is that India, with 1.3 billion people and soon to be the most populous country in the world, is likely to see large migrations. The heat and floods in the country are already killing hundreds of people a year, and many millions who are still dependent on subsistence agriculture are struggling with changing climate conditions.

“Our research suggests that populations in Latin America and the Caribbean, several countries in sub-Saharan Africa – especially in the Sahel region and East Africa – as well as western, southern and south-east Asia, are particularly at risk,” says co-author Anna Dimitrova from the Vienna Institute of Demography of the Austrian Academy of Sciences.

While the report is aimed at preparing governments for migrations that will inevitably happen in the future, with difficult consequences for both the migrants and the host country, the research suggests the best way of averting the coming crisis is to tackle climate change and reduce further rises in temperatures.

“The best way to protect those affected is to stabilise the global climate by rapidly reducing greenhouse gas emissions from burning fossil fuels as well as simultaneously to enhance adaptive capacity, such as through improving human capital,” says Jesus Crespo Cuaresma, a researcher with the IIASA World Population Program and professor of economics at the Vienna University of Economics and Business. − Climate News Network

Climate change is now driving mass migration, which will only worsen unless governments take global heating seriously.

LONDON, 15 September, 2020 −There is strong evidence that deteriorating environments caused by climate change are driving millions of people to resort to mass migration in their search for a better life, both within countries and across borders.

As temperatures rise these migrations will only increase, particularly in Latin America and India, which is predicted to overtake China as the country with the largest population by 2025.

An analysis of environment and migration, published in Nature Climate Change, of 30 studies of individual countries across the world shows that there is no one single factor that drives migration.

But most research has found that environmental hazards have a major influence. Rising temperature levels, changes in rainfall and single sudden events like hurricanes are all triggers.

Policies for improvement

The analysis, by the International Institute for Applied Systems Analysis (IIASA) in Austria and research partners across Europe, was undertaken to try to inform policy makers about how to avert mass human migration.

It points out that two of the most high-profile mass migration episodes in recent times – the Syrian refugee crisis in 2015 and the “migrant caravan” from Central America to the United States in 2018 – have been partly attributed to severe droughts in the countries concerned.

While some studies conclude that environmental factors were not the main driver of migration, most thought it was one of the primary causes. The analysis says governments should expect significantly higher migration flows in the future.

Perhaps surprisingly, given the publicity surrounding the issue, migrations were not centred on poor people trying to enter rich nations in Europe or North America. Instead, most movements were from the countryside to urban areas in the same country, particularly in agriculturally dependent countries, or from one middle-income country to another.

“The best way to protect those affected is to stabilise the global climate by rapidly reducing greenhouse gas emissions from burning fossil fuels”

People with particularly low incomes normally stayed where they were,  despite environmental pressures, because they had no way of financing a move, while richer people had the means to adapt to new circumstances and so they also stayed put.

“Environmental factors can drive migration, but the size of the effects depends on the particular economic and socio-political conditions in the countries,” explains the lead author Roman Hoffmann, from Germany’s Potsdam Institute for Climate Impact Research (PIK).

“In both low and high income countries, environmental impacts on migration are weaker – presumably because either people are too poor to leave and therefore essentially become trapped or, in wealthy countries, they have enough financial means to absorb the consequences. It is mainly in middle-income regions and those with a dependency on agriculture that we see strong effects.”

IIASA predicts future higher levels of environmental migration for countries in Central America, the Caribbean, Brazil and Argentina. In Africa it is the Sahel region south of the Sahara that is already drying out, and East Africa that has the highest potential for people migrating because of climate change.

Eyes on India

Perhaps the most disturbing prediction is that India, with 1.3 billion people and soon to be the most populous country in the world, is likely to see large migrations. The heat and floods in the country are already killing hundreds of people a year, and many millions who are still dependent on subsistence agriculture are struggling with changing climate conditions.

“Our research suggests that populations in Latin America and the Caribbean, several countries in sub-Saharan Africa – especially in the Sahel region and East Africa – as well as western, southern and south-east Asia, are particularly at risk,” says co-author Anna Dimitrova from the Vienna Institute of Demography of the Austrian Academy of Sciences.

While the report is aimed at preparing governments for migrations that will inevitably happen in the future, with difficult consequences for both the migrants and the host country, the research suggests the best way of averting the coming crisis is to tackle climate change and reduce further rises in temperatures.

“The best way to protect those affected is to stabilise the global climate by rapidly reducing greenhouse gas emissions from burning fossil fuels as well as simultaneously to enhance adaptive capacity, such as through improving human capital,” says Jesus Crespo Cuaresma, a researcher with the IIASA World Population Program and professor of economics at the Vienna University of Economics and Business. − Climate News Network