Tag Archives: Carbon Dioxide

Science counts humankind’s carbon output

We leave the planet’s volcanos far behind on greenhouse gas emissions: humankind’s carbon output can exceed theirs by 40 times – to our cost.

LONDON, 7 October, 2019 – Scientists now know how much carbon dioxide is pumped into the atmosphere and oceans by volcanos and volcanic fissures annually – perhaps as much as 360 million tonnes – and another crucial statistic, too: humankind’s carbon output.

They know that, by burning fossil fuels and clearing forests and building cities, we now emit much more than that: between 40 and 100 times more.

They can also now tell you how much carbon is in circulation above the Earth’s surface, in the oceans, on land, and in the atmosphere: the answer is 43,500 billion tonnes. That is about two-tenths of 1% of all the carbon locked for the moment in the Earth’s crust, mantle and core.

The research delivers no answers and no new directions for climate science, and in particular for governments and international agencies concerned about global heating and the climate emergency.

This is the ultimate in basic, bedrock, accounting: to understand the carbon cycle – the continuous traffic of carbon between atmosphere, ocean, rocks and living things – researchers need to have a better idea of the scale of what they like to call the carbon budget.

“To secure a sustainable future, it is of utmost importance that we understand Earth’s entire carbon cycle”

And after a decade of research, a partnership of more than 500 scientists from 39 countries working on more than 100 separate projects has delivered a set of down-to-earth answers in a new issue of the journal Elements.

The total estimate – it can only be an estimate – for the entire stock of carbon at the surface, in the crust and in the Earth’s mantle is around 1.85 billion billion tonnes.

And the observations of volcanic discharges of carbon are vital to understanding the cycle: this more or less steady renewal from deep below the surface is what has made life’s evolution from microbe to monkey puzzle-tree, from bacterium to Bactrian camel, possible over the last billion years.

Carbon from the atmosphere is absorbed by forests and sea meadows and buried, sometimes as shell and bone and limestone, sometimes as coal and oil and methane gas, and the carbon lost to the atmosphere is steadily replenished by deep hot sources from the Earth’s crust.

The study also highlights the nature of the climate emergency: by mining, drilling or quarrying for fossil fuels with which to drive chain saws through forests and bake limestone to make cement, humans are now returning ancient deposits of fossil carbon to the atmosphere at an overwhelming rate.

Doubling carbon levels

For most of human history, human ancestors, like all other life forms, evolved in a low-carbon atmosphere. In the past 60 years, humans have begun to double the normal levels of atmospheric carbon dioxide, a potent and enduring greenhouse gas.

And one pay-off of this increasingly urgent interest in the carbon cycle is that the researchers in the Deep Carbon Observatory partnership have added to fundamental knowledge and established what might be the limits of the knowable. They also have a better idea of carbon’s natural cycle.

“Carbon, the basis of all life and the energy source vital to humanity, moves through this planet from its mantle to the atmosphere. To secure a sustainable future, it is of utmost importance that we understand Earth’s entire carbon cycle,” said Marie Edmonds of the University of Cambridge, UK, one of the partnership.

“Key to unravelling the planet’s natural carbon cycle is quantifying how much carbon there is and where, how much moves – the flux – and how quickly, from Deep Earth reservoirs to the surface and back again.”

The Observatory recently identified the huge volume of subterranean life far below the planet’s surface. But the details of the carbon traffic in atmosphere, soils and waters are still somewhat muddy.

Only a start

The issue is vital to planning for what should be the accelerating shift from fossil fuels to solar and wind power, and researchers have been looking for new ways to assess vegetation uptake, the role of microbes in the world’s soils and the play between carbon and the world’s rivers.

The same study throws light on the periodic role of volcanic and magma discharges and other difficult-to-predict events in disrupting life on Earth. At least four times in the past 500 million years enormous discharges of carbon have changed climates and triggered mass extinctions.

And a giant meteor impact 66 million years ago is thought to have released up to 1400 billion tons of carbon dioxide, rapidly warmed the planet and helped in the mass extinction of plants and animals, including the dinosaurs.

The research continues: scientists will meet soon in Washington to start discussing the next decade of work.

“While we celebrate progress, we underline that deep Earth remains a highly unpredictable scientific frontier,” said Tobias Fischer of the University of New Mexico, another of the authors. “We have only truly started to dent current boundaries of our knowledge.” – Climate News Network

We leave the planet’s volcanos far behind on greenhouse gas emissions: humankind’s carbon output can exceed theirs by 40 times – to our cost.

LONDON, 7 October, 2019 – Scientists now know how much carbon dioxide is pumped into the atmosphere and oceans by volcanos and volcanic fissures annually – perhaps as much as 360 million tonnes – and another crucial statistic, too: humankind’s carbon output.

They know that, by burning fossil fuels and clearing forests and building cities, we now emit much more than that: between 40 and 100 times more.

They can also now tell you how much carbon is in circulation above the Earth’s surface, in the oceans, on land, and in the atmosphere: the answer is 43,500 billion tonnes. That is about two-tenths of 1% of all the carbon locked for the moment in the Earth’s crust, mantle and core.

The research delivers no answers and no new directions for climate science, and in particular for governments and international agencies concerned about global heating and the climate emergency.

This is the ultimate in basic, bedrock, accounting: to understand the carbon cycle – the continuous traffic of carbon between atmosphere, ocean, rocks and living things – researchers need to have a better idea of the scale of what they like to call the carbon budget.

“To secure a sustainable future, it is of utmost importance that we understand Earth’s entire carbon cycle”

And after a decade of research, a partnership of more than 500 scientists from 39 countries working on more than 100 separate projects has delivered a set of down-to-earth answers in a new issue of the journal Elements.

The total estimate – it can only be an estimate – for the entire stock of carbon at the surface, in the crust and in the Earth’s mantle is around 1.85 billion billion tonnes.

And the observations of volcanic discharges of carbon are vital to understanding the cycle: this more or less steady renewal from deep below the surface is what has made life’s evolution from microbe to monkey puzzle-tree, from bacterium to Bactrian camel, possible over the last billion years.

Carbon from the atmosphere is absorbed by forests and sea meadows and buried, sometimes as shell and bone and limestone, sometimes as coal and oil and methane gas, and the carbon lost to the atmosphere is steadily replenished by deep hot sources from the Earth’s crust.

The study also highlights the nature of the climate emergency: by mining, drilling or quarrying for fossil fuels with which to drive chain saws through forests and bake limestone to make cement, humans are now returning ancient deposits of fossil carbon to the atmosphere at an overwhelming rate.

Doubling carbon levels

For most of human history, human ancestors, like all other life forms, evolved in a low-carbon atmosphere. In the past 60 years, humans have begun to double the normal levels of atmospheric carbon dioxide, a potent and enduring greenhouse gas.

And one pay-off of this increasingly urgent interest in the carbon cycle is that the researchers in the Deep Carbon Observatory partnership have added to fundamental knowledge and established what might be the limits of the knowable. They also have a better idea of carbon’s natural cycle.

“Carbon, the basis of all life and the energy source vital to humanity, moves through this planet from its mantle to the atmosphere. To secure a sustainable future, it is of utmost importance that we understand Earth’s entire carbon cycle,” said Marie Edmonds of the University of Cambridge, UK, one of the partnership.

“Key to unravelling the planet’s natural carbon cycle is quantifying how much carbon there is and where, how much moves – the flux – and how quickly, from Deep Earth reservoirs to the surface and back again.”

The Observatory recently identified the huge volume of subterranean life far below the planet’s surface. But the details of the carbon traffic in atmosphere, soils and waters are still somewhat muddy.

Only a start

The issue is vital to planning for what should be the accelerating shift from fossil fuels to solar and wind power, and researchers have been looking for new ways to assess vegetation uptake, the role of microbes in the world’s soils and the play between carbon and the world’s rivers.

The same study throws light on the periodic role of volcanic and magma discharges and other difficult-to-predict events in disrupting life on Earth. At least four times in the past 500 million years enormous discharges of carbon have changed climates and triggered mass extinctions.

And a giant meteor impact 66 million years ago is thought to have released up to 1400 billion tons of carbon dioxide, rapidly warmed the planet and helped in the mass extinction of plants and animals, including the dinosaurs.

The research continues: scientists will meet soon in Washington to start discussing the next decade of work.

“While we celebrate progress, we underline that deep Earth remains a highly unpredictable scientific frontier,” said Tobias Fischer of the University of New Mexico, another of the authors. “We have only truly started to dent current boundaries of our knowledge.” – Climate News Network

Human ancestors lived in a low-carbon world

Carbon dioxide levels are higher now than in all human history, and prehistory too: a low-carbon world nurtured our distant forebears.

LONDON, 4 October, 2019 – For the entire 2.5 million years of the Ice Age epoch called the Pleistocene, it was a low-carbon world. Atmospheric carbon dioxide hovered around 230 parts per million. Not only did Homo sapiens evolve on a low-carbon planet, so did Homo erectus and most other human species now known only from fossil evidence in Europe and Asia.

And this long history of a planet kept cool and stable by low levels of greenhouse gas in the atmosphere continued long after the discovery of fire, the Stone Age, the Bronze Age, the Iron Age, the fall and rise of empires and the Industrial Revolution.

Only in 1965 did carbon dioxide levels pass 320 ppm, after a century of exploitation of fossil fuels that released ancient carbon back into atmospheric circulation.

By 2019, the carbon dioxide concentration in the atmosphere had tipped 410 ppm and is still rising. In less than a century, human action had raised planetary average temperatures by around 1°C. At present rates, this average could reach 3°C by the end of this century.

Researchers have known for a century that humans emerged in a cooler world, but much of the story of the distant past was based on the evidence of fossils and sedimentary rocks. The latest research pushes the detailed atmospheric carbon dioxide accounting back to at least 2.5 million years.

“This current high carbon dioxide experiment is not only an experiment for the climate and the environment – it’s an experiment for us”

Researchers report in the journal Nature Communications that they studied the pattern of carbon isotope readings preserved in the deep yellow soils of China’s loess plateau. What they found confirmed 800,000 years of annual evidence from the ice cores of Antarctica and Greenland – and far beyond that limit.

The wind-blown loess of China dates back to at least 22 million years and each successive layer carries isotope evidence that can be read as testimony to the atmospheric conditions in which the soils were laid down.

The latest find confirms that the normal state of the planet during human evolution was cool, with low levels of atmospheric carbon. Homo erectus was the first known human predecessor to exploit fire, systematically fashion stone hand axes, and to leave Africa for Asia and Europe.

“According to this research, from the first Homo erectus, which is currently dated to 2.1 to 1.8 million years ago, we have lived in a low-carbon environment – concentrations were less than 320 parts per million,” said Yige Zhang, a geoscientist at Texas A&M University in the US, who worked with colleagues in Nanjing, China, and California Institute of Technology.

“So this current high carbon dioxide experiment is not only an experiment for the climate and the environment – it’s an experiment for us, for ourselves.” – Climate News Network

Carbon dioxide levels are higher now than in all human history, and prehistory too: a low-carbon world nurtured our distant forebears.

LONDON, 4 October, 2019 – For the entire 2.5 million years of the Ice Age epoch called the Pleistocene, it was a low-carbon world. Atmospheric carbon dioxide hovered around 230 parts per million. Not only did Homo sapiens evolve on a low-carbon planet, so did Homo erectus and most other human species now known only from fossil evidence in Europe and Asia.

And this long history of a planet kept cool and stable by low levels of greenhouse gas in the atmosphere continued long after the discovery of fire, the Stone Age, the Bronze Age, the Iron Age, the fall and rise of empires and the Industrial Revolution.

Only in 1965 did carbon dioxide levels pass 320 ppm, after a century of exploitation of fossil fuels that released ancient carbon back into atmospheric circulation.

By 2019, the carbon dioxide concentration in the atmosphere had tipped 410 ppm and is still rising. In less than a century, human action had raised planetary average temperatures by around 1°C. At present rates, this average could reach 3°C by the end of this century.

Researchers have known for a century that humans emerged in a cooler world, but much of the story of the distant past was based on the evidence of fossils and sedimentary rocks. The latest research pushes the detailed atmospheric carbon dioxide accounting back to at least 2.5 million years.

“This current high carbon dioxide experiment is not only an experiment for the climate and the environment – it’s an experiment for us”

Researchers report in the journal Nature Communications that they studied the pattern of carbon isotope readings preserved in the deep yellow soils of China’s loess plateau. What they found confirmed 800,000 years of annual evidence from the ice cores of Antarctica and Greenland – and far beyond that limit.

The wind-blown loess of China dates back to at least 22 million years and each successive layer carries isotope evidence that can be read as testimony to the atmospheric conditions in which the soils were laid down.

The latest find confirms that the normal state of the planet during human evolution was cool, with low levels of atmospheric carbon. Homo erectus was the first known human predecessor to exploit fire, systematically fashion stone hand axes, and to leave Africa for Asia and Europe.

“According to this research, from the first Homo erectus, which is currently dated to 2.1 to 1.8 million years ago, we have lived in a low-carbon environment – concentrations were less than 320 parts per million,” said Yige Zhang, a geoscientist at Texas A&M University in the US, who worked with colleagues in Nanjing, China, and California Institute of Technology.

“So this current high carbon dioxide experiment is not only an experiment for the climate and the environment – it’s an experiment for us, for ourselves.” – Climate News Network

Rugby stars are losing their Pacific islands

Whatever happens on the pitches, rugby stars from the Pacific islands face a battle back home to save their ancestral lands from rising sea levels.

LONDON, 1 October, 2019 – Players from the Pacific islands are performing a prominent role in the intense battles at present going on at the rugby world cup in Japan.

Away from the rough and tumble on the pitch, the players are facing an even bigger challenge back home as their island nations come under increasing threat from climate change, in particular from ever-rising sea levels.

A recent report by the Intergovernmental Panel on Climate Change (IPCC) warns of the catastrophic effect rising sea levels – mainly caused by the melting of ice at the poles – will have on billions of people living in coastal areas and in island states around the world.

In the low-lying island nations of the Pacific, climate change is already having an impact. Coastal communities are frequently inundated by rising seas. Salty seawater poisons precious supplies of fresh water.

Crops are lost and homes damaged. Warming seas are killing off coral reefs, a key source of fish and an industry on which many islanders depend for their living.

Exploited

A report by the charity Christian Aid, focusing on the rugby world cup, says that while Pacific island teams Fiji, Tonga and Samoa are playing a central role in the tournament in Japan, they are, at the same time, being exploited and harmed by the actions of bigger and richer nations involved, including Australia, New Zealand and England.

The report points out that Pacific island states are among the lowest emitters of climate-changing carbon dioxide and other greenhouse gases. Yet they are among those suffering most from a warming world.

Samoa emits 0.7 tonnes of CO2 per capita each year. The equivalent figure for Australia is 16.5 tonnes and for host Japan is 10.4 tonnes.

Jonny Fa’amatuainu is a former Samoan international who has also played for rugby clubs in England, Wales and Japan.

“As a Pacific Island rugby player, tackling the climate crisis is close to my heart. My grandparents and other families who lived in a village on the coast of Samoa moved inland two years ago because of climate change”, he says.

“The island nations in the Pacific are some of the most vulnerable in the world and they have done almost nothing to cause their plight”

“The Pacific Islands are the soul of our sport and we have produced some of the most dynamic and exciting players on the planet … climate change is a crisis these countries did not cause yet it’s a fight they are suffering from the most.

“It’s a fight they need the help of the rugby community to win.”

The Christian Aid report says climate change threatens to undermine the Pacific Islands’ economies. Tourists will stop visiting and young people will be forced to leave, with up to 1.7 million likely to move from their homes in the region over the next 30 years.

Cyclone Gita, which devastated many parts of Tonga last year, was the strongest storm to hit the nation since records began. The report says global warming means such storms will be more frequent across the region in the years ahead.

The study also highlights the way in which many Pacific island rugby players are treated, being paid wages only a fraction of those earned by their counterparts in richer countries. The teams are also often excluded from various international tournaments.

Foot-dragging

“Climate change is the ultimate injustice issue and nowhere is that captured more clearly than among the nations taking part in the rugby world cup”, says Katherine Kramer of Christian Aid, the author of the report.

“The island nations in the Pacific are some of the most vulnerable in the world and they have done almost nothing to cause their plight.

“The main culprits for causing the climate crisis are European nations as well as major coal burners like Australia, the US and Japan.

“Not only have they caused the current dire situation, but they are dragging their feet on making the needed transition to a zero-carbon economy.” – Climate News Network

Whatever happens on the pitches, rugby stars from the Pacific islands face a battle back home to save their ancestral lands from rising sea levels.

LONDON, 1 October, 2019 – Players from the Pacific islands are performing a prominent role in the intense battles at present going on at the rugby world cup in Japan.

Away from the rough and tumble on the pitch, the players are facing an even bigger challenge back home as their island nations come under increasing threat from climate change, in particular from ever-rising sea levels.

A recent report by the Intergovernmental Panel on Climate Change (IPCC) warns of the catastrophic effect rising sea levels – mainly caused by the melting of ice at the poles – will have on billions of people living in coastal areas and in island states around the world.

In the low-lying island nations of the Pacific, climate change is already having an impact. Coastal communities are frequently inundated by rising seas. Salty seawater poisons precious supplies of fresh water.

Crops are lost and homes damaged. Warming seas are killing off coral reefs, a key source of fish and an industry on which many islanders depend for their living.

Exploited

A report by the charity Christian Aid, focusing on the rugby world cup, says that while Pacific island teams Fiji, Tonga and Samoa are playing a central role in the tournament in Japan, they are, at the same time, being exploited and harmed by the actions of bigger and richer nations involved, including Australia, New Zealand and England.

The report points out that Pacific island states are among the lowest emitters of climate-changing carbon dioxide and other greenhouse gases. Yet they are among those suffering most from a warming world.

Samoa emits 0.7 tonnes of CO2 per capita each year. The equivalent figure for Australia is 16.5 tonnes and for host Japan is 10.4 tonnes.

Jonny Fa’amatuainu is a former Samoan international who has also played for rugby clubs in England, Wales and Japan.

“As a Pacific Island rugby player, tackling the climate crisis is close to my heart. My grandparents and other families who lived in a village on the coast of Samoa moved inland two years ago because of climate change”, he says.

“The island nations in the Pacific are some of the most vulnerable in the world and they have done almost nothing to cause their plight”

“The Pacific Islands are the soul of our sport and we have produced some of the most dynamic and exciting players on the planet … climate change is a crisis these countries did not cause yet it’s a fight they are suffering from the most.

“It’s a fight they need the help of the rugby community to win.”

The Christian Aid report says climate change threatens to undermine the Pacific Islands’ economies. Tourists will stop visiting and young people will be forced to leave, with up to 1.7 million likely to move from their homes in the region over the next 30 years.

Cyclone Gita, which devastated many parts of Tonga last year, was the strongest storm to hit the nation since records began. The report says global warming means such storms will be more frequent across the region in the years ahead.

The study also highlights the way in which many Pacific island rugby players are treated, being paid wages only a fraction of those earned by their counterparts in richer countries. The teams are also often excluded from various international tournaments.

Foot-dragging

“Climate change is the ultimate injustice issue and nowhere is that captured more clearly than among the nations taking part in the rugby world cup”, says Katherine Kramer of Christian Aid, the author of the report.

“The island nations in the Pacific are some of the most vulnerable in the world and they have done almost nothing to cause their plight.

“The main culprits for causing the climate crisis are European nations as well as major coal burners like Australia, the US and Japan.

“Not only have they caused the current dire situation, but they are dragging their feet on making the needed transition to a zero-carbon economy.” – Climate News Network

Extremes of global heat bring tipping points closer

It makes good business sense to contain planetary warming to 1.5°C. Passing the Paris target spells disaster, with more extremes of global heat.

LONDON, 23 September, 2019 – Urgent action on climate change will be costly. But inaction could be four or five times more expensive, according to new climate accounting: extremes of global heat are on the increase.

Submarine heatwaves happen three times more often that they did in 1980. Ocean warming events can devastate coral reefs and trigger even more damage from more intense acidification and oxygen loss in the seas, with disastrous consequences for fishery and seafood.

The ecosystems on which all living things – including humans – depend are shifting away from the tropics at up to 40kms a year. Extremes of torrential rainfall, drought and tropical cyclones are becoming measurably more intense.

And all this has happened because global mean surface temperatures have risen in the last century by about 1°C, thanks to ever more carbon dioxide in the atmosphere, a consequence of profligate use of fossil fuels to drive human expansion.

“People from small island states and low-lying countries are in the immediate crosshairs of climate change. I am very concerned about the future for these people”

Forecasts suggest humans could tip the planet to a rise of 1.5°C as early as 2030. This is the limit proposed by 195 nations in Paris in 2015 when they promised to keep global heating to “well below” 2°C by the end of the century.

And now researchers once again warn in the journal Science that even the seemingly small gap between 1.5°C and 2°C could spell a colossal difference in long-term outcomes. Right now, the planet is on track to hit or surpass 3°C by 2100. The case for drastic reductions in greenhouse gas emissions is now more compelling and urgent than ever.

“First, we have under-estimated the sensitivity of natural and human systems to climate change and the speed at which these things are happening. Second, we have under-appreciated the synergistic nature of climate threats – with outcomes tending to be worse than the sum of the parts,” said Ove Hoegh-Guldberg of the University of Queensland in Australia, who led the study.

“This is resulting in rapid and comprehensive climate impacts, with growing damage to people, ecosystems and livelihoods.”

Harder to forecast

And Daniela Jacob, who directs Germany’s Climate Service Centre, added: “We are already in new territory. The ‘novelty’ of the weather is making our ability to forecast and respond to weather-related phenomena very difficult.”

The two scientists were part of a much larger world-wide team of researchers who looked at the risks that arrive with rapid change: damage to forests, farms and wildlife; to coastal communities as sea levels rise and storms multiply.

Their message is clear. There would be huge benefits to containing average global temperature rise to no more than 1.5C above the long-term average for most of human history.

“This is not an academic issue, it is a matter of life and death for people everywhere.” said Michael Taylor, dean of science at the University of the West Indies in Jamaica.

Weak commitments

“That said, people from small island states and low-lying countries are in the immediate crosshairs of climate change. I am very concerned about the future for these people.”

So far, the commitments made by most nations are simply too feeble. That risks condemning many nations to chaos and harm, and, as usual, those most vulnerable would be the poorest.

“To avoid this, we must accelerate action and tighten emission reduction targets so that they fall in line with the Paris Agreement. As we show, this is much less costly than suffering the impacts of 2°C or more of climate change,” said Professor Hoegh-Guldberg.

“Tackling climate change is a tall order. However, there is no alternative from the perspective of human well-being − and too much at stake not to act urgently on this issue.” − Climate News Network

It makes good business sense to contain planetary warming to 1.5°C. Passing the Paris target spells disaster, with more extremes of global heat.

LONDON, 23 September, 2019 – Urgent action on climate change will be costly. But inaction could be four or five times more expensive, according to new climate accounting: extremes of global heat are on the increase.

Submarine heatwaves happen three times more often that they did in 1980. Ocean warming events can devastate coral reefs and trigger even more damage from more intense acidification and oxygen loss in the seas, with disastrous consequences for fishery and seafood.

The ecosystems on which all living things – including humans – depend are shifting away from the tropics at up to 40kms a year. Extremes of torrential rainfall, drought and tropical cyclones are becoming measurably more intense.

And all this has happened because global mean surface temperatures have risen in the last century by about 1°C, thanks to ever more carbon dioxide in the atmosphere, a consequence of profligate use of fossil fuels to drive human expansion.

“People from small island states and low-lying countries are in the immediate crosshairs of climate change. I am very concerned about the future for these people”

Forecasts suggest humans could tip the planet to a rise of 1.5°C as early as 2030. This is the limit proposed by 195 nations in Paris in 2015 when they promised to keep global heating to “well below” 2°C by the end of the century.

And now researchers once again warn in the journal Science that even the seemingly small gap between 1.5°C and 2°C could spell a colossal difference in long-term outcomes. Right now, the planet is on track to hit or surpass 3°C by 2100. The case for drastic reductions in greenhouse gas emissions is now more compelling and urgent than ever.

“First, we have under-estimated the sensitivity of natural and human systems to climate change and the speed at which these things are happening. Second, we have under-appreciated the synergistic nature of climate threats – with outcomes tending to be worse than the sum of the parts,” said Ove Hoegh-Guldberg of the University of Queensland in Australia, who led the study.

“This is resulting in rapid and comprehensive climate impacts, with growing damage to people, ecosystems and livelihoods.”

Harder to forecast

And Daniela Jacob, who directs Germany’s Climate Service Centre, added: “We are already in new territory. The ‘novelty’ of the weather is making our ability to forecast and respond to weather-related phenomena very difficult.”

The two scientists were part of a much larger world-wide team of researchers who looked at the risks that arrive with rapid change: damage to forests, farms and wildlife; to coastal communities as sea levels rise and storms multiply.

Their message is clear. There would be huge benefits to containing average global temperature rise to no more than 1.5C above the long-term average for most of human history.

“This is not an academic issue, it is a matter of life and death for people everywhere.” said Michael Taylor, dean of science at the University of the West Indies in Jamaica.

Weak commitments

“That said, people from small island states and low-lying countries are in the immediate crosshairs of climate change. I am very concerned about the future for these people.”

So far, the commitments made by most nations are simply too feeble. That risks condemning many nations to chaos and harm, and, as usual, those most vulnerable would be the poorest.

“To avoid this, we must accelerate action and tighten emission reduction targets so that they fall in line with the Paris Agreement. As we show, this is much less costly than suffering the impacts of 2°C or more of climate change,” said Professor Hoegh-Guldberg.

“Tackling climate change is a tall order. However, there is no alternative from the perspective of human well-being − and too much at stake not to act urgently on this issue.” − Climate News Network

Faster global warming may bring much more heat

Climate scientists are haunted by a global temperature rise 56 million years ago, which could mean much more heat very soon.

LONDON,19 September, 2019 − We could in the near future be experiencing much more heat than we now expect. As carbon dioxide levels rise, global warming could accelerate, rather than merely keep pace with the levels of greenhouse gases in the atmosphere.

This is a lesson to be drawn from new computer simulations of the conditions that must have precipitated a dramatic shift in global climate 56 million years ago, when atmospheric carbon dioxide levels rose at least 1000 parts per million (ppm) and perhaps substantially higher.

For most of human history, carbon dioxide levels stood at around 285ppm. They have now passed 400ppm. By the century’s end, if humans go on burning ever greater quantities of fossil fuels to drive global heating, then these could reach 1000 ppm.

The last time that happened, during a period known as the Early Eocene 56 million years ago, the surface temperatures became up to 9°C hotter than today. The period has been repeatedly explored as a lesson for the pattern of events that might follow from global heating by profligate combustion of fossil fuels.

“The temperature response to an increase in carbon dioxide in the future might be larger than the response to the same increase in CO2 now. This is not good news for us”

The polar ice melted. Antarctic ocean temperatures reached 20°C. Sea levels rose dramatically, oceans became increasingly acidic, mammals evolved to smaller dimensions and crocodiles haunted the Arctic.

It is a principle of geology that the present is a key to the past – and it follows that the past must contain lessons for the future. So climate scientists have always taken a close interest in the Early Eocene.

US scientists report in the journal Science Advances that, for the first time, they were able to simulate the extreme surface warmth of the Early Eocene in a computer model. After decades of geological investigation, there is not much argument about the real conditions 56 million years ago, and the immensely high levels of carbon dioxide. What is not clear is quite how the link between atmosphere and temperature in that vanished era must have played out.

Research of this kind is based on mathematical simulation, which is only a tentative guide to what might actually happen on a rapidly changing planet, but the scientists count their results a success. Previous attempts have simply been built around the rise in atmospheric carbon dioxide.

Temperatures too low

This study managed to incorporate models of water vapour, cloud formation, atmospheric aerosols and other factors that would have set up a system of feedbacks that might lead to the sweltering tropics and the very warm polar regions of the era.

“For decades, the models have underestimated these temperatures, and the community has long assumed that the problem was with the geological data, or that there was a warming mechanism that had not been recognized,” said Christopher Poulsen, of the University of Michigan.

His co-author Jessica Tierney of the University of Arizona said: “For the first time a climate model matches the geological evidence out of the box − that is, without deliberate tweaks made to the model. It’s a breakthrough in our understanding of past climates.”

Other scientists have already predicted that what happened in the Early Eocene could turn out to be a lesson for what is happening now. The finding may play into the larger puzzle of something called “climate sensitivity”: that is, how so much extra carbon dioxide might lead to so much average global temperature rise?

Risk of underestimation

Researchers have assumed that the one would be in step with the other. But the latest finding also raises the possibility that warming might indeed accelerate as carbon dioxide concentrations rise. So far, the world has warmed by around 1°C in the last century, with the planet perhaps on track to pass 3°C by 2100.

But more recent studies have warned that this could be a serious underestimate. The lesson of the Early Eocene, a period of change that played out over hundreds of thousands of years, is that the questions of climate sensitivity have yet to be settled.

“We were surprised that the climate sensitivity increased as much as it did with increasing carbon dioxide levels,” said Jiang Zhu, of the University of Michigan, who led the study.

“It is a scary finding because it indicates that the temperature response to an increase in carbon dioxide in the future might be larger than the response to the same increase in CO2 now. This is not good news for us.” − Climate News Network

Climate scientists are haunted by a global temperature rise 56 million years ago, which could mean much more heat very soon.

LONDON,19 September, 2019 − We could in the near future be experiencing much more heat than we now expect. As carbon dioxide levels rise, global warming could accelerate, rather than merely keep pace with the levels of greenhouse gases in the atmosphere.

This is a lesson to be drawn from new computer simulations of the conditions that must have precipitated a dramatic shift in global climate 56 million years ago, when atmospheric carbon dioxide levels rose at least 1000 parts per million (ppm) and perhaps substantially higher.

For most of human history, carbon dioxide levels stood at around 285ppm. They have now passed 400ppm. By the century’s end, if humans go on burning ever greater quantities of fossil fuels to drive global heating, then these could reach 1000 ppm.

The last time that happened, during a period known as the Early Eocene 56 million years ago, the surface temperatures became up to 9°C hotter than today. The period has been repeatedly explored as a lesson for the pattern of events that might follow from global heating by profligate combustion of fossil fuels.

“The temperature response to an increase in carbon dioxide in the future might be larger than the response to the same increase in CO2 now. This is not good news for us”

The polar ice melted. Antarctic ocean temperatures reached 20°C. Sea levels rose dramatically, oceans became increasingly acidic, mammals evolved to smaller dimensions and crocodiles haunted the Arctic.

It is a principle of geology that the present is a key to the past – and it follows that the past must contain lessons for the future. So climate scientists have always taken a close interest in the Early Eocene.

US scientists report in the journal Science Advances that, for the first time, they were able to simulate the extreme surface warmth of the Early Eocene in a computer model. After decades of geological investigation, there is not much argument about the real conditions 56 million years ago, and the immensely high levels of carbon dioxide. What is not clear is quite how the link between atmosphere and temperature in that vanished era must have played out.

Research of this kind is based on mathematical simulation, which is only a tentative guide to what might actually happen on a rapidly changing planet, but the scientists count their results a success. Previous attempts have simply been built around the rise in atmospheric carbon dioxide.

Temperatures too low

This study managed to incorporate models of water vapour, cloud formation, atmospheric aerosols and other factors that would have set up a system of feedbacks that might lead to the sweltering tropics and the very warm polar regions of the era.

“For decades, the models have underestimated these temperatures, and the community has long assumed that the problem was with the geological data, or that there was a warming mechanism that had not been recognized,” said Christopher Poulsen, of the University of Michigan.

His co-author Jessica Tierney of the University of Arizona said: “For the first time a climate model matches the geological evidence out of the box − that is, without deliberate tweaks made to the model. It’s a breakthrough in our understanding of past climates.”

Other scientists have already predicted that what happened in the Early Eocene could turn out to be a lesson for what is happening now. The finding may play into the larger puzzle of something called “climate sensitivity”: that is, how so much extra carbon dioxide might lead to so much average global temperature rise?

Risk of underestimation

Researchers have assumed that the one would be in step with the other. But the latest finding also raises the possibility that warming might indeed accelerate as carbon dioxide concentrations rise. So far, the world has warmed by around 1°C in the last century, with the planet perhaps on track to pass 3°C by 2100.

But more recent studies have warned that this could be a serious underestimate. The lesson of the Early Eocene, a period of change that played out over hundreds of thousands of years, is that the questions of climate sensitivity have yet to be settled.

“We were surprised that the climate sensitivity increased as much as it did with increasing carbon dioxide levels,” said Jiang Zhu, of the University of Michigan, who led the study.

“It is a scary finding because it indicates that the temperature response to an increase in carbon dioxide in the future might be larger than the response to the same increase in CO2 now. This is not good news for us.” − Climate News Network

Climate models predict bigger heat rise ahead

Scientists using new climate models say a bigger heat rise than expected is possible by the end of the century.

LONDON, 18 September, 2019 − Greenhouse gases are raising the Earth’s temperature faster than previously thought, according to new climate models due to replace those used in current UN projections − meaning a bigger heat rise by 2100 than thought likely.

Separate models at two French research centres suggest that by then average global temperatures could have risen by 6.5 to 7.0°C above pre-industrial levels if carbon emissions continue at their present rate, the website phys.org reports.

Scientists − and most of the world’s governments − finalised the Paris Agreement on climate change in 2015, undertaking to keep the warming increase to a maximum of 2°C, and if possible to only 1.5°C.

Almost two years ago, a UN report deemed it “very likely” that global temperatures would reach 3°C by 2100, even if the Paris goals were fully implemented. But the French warning suggests a planet with double that predicted increase. And as the increase would be only an average, some parts of the world would be even more seriously affected.

“What we need to do to keep warming to safe levels is extremely simple. Global greenhouse gas emissions need to decline today rather than tomorrow, and global CO2 emissions should be brought to net zero”

“With our two models, we see that the scenario known as SSP1 2.6 − which normally allows us to stay under 2°C − doesn’t quite get us there,” Olivier Boucher, head of the Institute Pierre Simon Laplace climate modelling centre in Paris, told the French news agency AFP.

With barely one degree Celsius of warming so far, the world is already having to cope with more heat waves, droughts, floods and extreme weather, much of it made more destructive by rising seas.

Beyond Paris, a new generation of about 30 models known collectively as CMIP6 − including the two revealed by France − will underpin the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC): the full report is due in 2022.

“CMIP6 clearly includes the latest modelling improvements”, even as important uncertainties remain, Joeri Rogelj, an associate professor at Imperial College London and an IPCC lead author, told AFP.

More accurate

These include increased supercomputing power and sharper representations of weather systems, natural and man-made particles, and how clouds evolve in a warming world.

“We have better models now,” said Dr Boucher. “They have better resolution, and they represent current climate trends more accurately.”

A core finding of the new models is that increased levels of CO2 in the atmosphere will warm the Earth’s surface more easily than earlier calculations had suggested. If confirmed, this higher “equilibrium climate sensitivity”, or ECS, means humanity’s carbon budget − our total emissions allowance − is likely to shrink.

The French models are among the first to be released, but others developed independently have come to the same unsettling conclusion, Dr Boucher said. “The most respected ones − from the United States, and Britain’s Met Office − also show a higher ECS” than the previous generation of models, he said.

Less adaptation time

“A higher ECS means a greater likelihood of reaching higher levels of global warming, even with deeper emissions cuts”, Boucher and two British scientists − Professor Stephen Belcher and Professor Rowan Sutton from the UK National Centre for Atmospheric Science − wrote in a blog earlier this year.

“Higher warming would allow less time to adapt and mean a greater likelihood of passing climate ‘tipping points’ such as thawing of permafrost, which would further accelerate warming.”

“Unfortunately, our global failure to implement meaningful action on climate change over recent decades has put us in a situation where what we need to do to keep warming to safe levels is extremely simple”, said Dr Rogelj.

“Global greenhouse gas emissions need to decline today rather than tomorrow, and global CO2 emissions should be brought to net zero.” − Climate News Network

Scientists using new climate models say a bigger heat rise than expected is possible by the end of the century.

LONDON, 18 September, 2019 − Greenhouse gases are raising the Earth’s temperature faster than previously thought, according to new climate models due to replace those used in current UN projections − meaning a bigger heat rise by 2100 than thought likely.

Separate models at two French research centres suggest that by then average global temperatures could have risen by 6.5 to 7.0°C above pre-industrial levels if carbon emissions continue at their present rate, the website phys.org reports.

Scientists − and most of the world’s governments − finalised the Paris Agreement on climate change in 2015, undertaking to keep the warming increase to a maximum of 2°C, and if possible to only 1.5°C.

Almost two years ago, a UN report deemed it “very likely” that global temperatures would reach 3°C by 2100, even if the Paris goals were fully implemented. But the French warning suggests a planet with double that predicted increase. And as the increase would be only an average, some parts of the world would be even more seriously affected.

“What we need to do to keep warming to safe levels is extremely simple. Global greenhouse gas emissions need to decline today rather than tomorrow, and global CO2 emissions should be brought to net zero”

“With our two models, we see that the scenario known as SSP1 2.6 − which normally allows us to stay under 2°C − doesn’t quite get us there,” Olivier Boucher, head of the Institute Pierre Simon Laplace climate modelling centre in Paris, told the French news agency AFP.

With barely one degree Celsius of warming so far, the world is already having to cope with more heat waves, droughts, floods and extreme weather, much of it made more destructive by rising seas.

Beyond Paris, a new generation of about 30 models known collectively as CMIP6 − including the two revealed by France − will underpin the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC): the full report is due in 2022.

“CMIP6 clearly includes the latest modelling improvements”, even as important uncertainties remain, Joeri Rogelj, an associate professor at Imperial College London and an IPCC lead author, told AFP.

More accurate

These include increased supercomputing power and sharper representations of weather systems, natural and man-made particles, and how clouds evolve in a warming world.

“We have better models now,” said Dr Boucher. “They have better resolution, and they represent current climate trends more accurately.”

A core finding of the new models is that increased levels of CO2 in the atmosphere will warm the Earth’s surface more easily than earlier calculations had suggested. If confirmed, this higher “equilibrium climate sensitivity”, or ECS, means humanity’s carbon budget − our total emissions allowance − is likely to shrink.

The French models are among the first to be released, but others developed independently have come to the same unsettling conclusion, Dr Boucher said. “The most respected ones − from the United States, and Britain’s Met Office − also show a higher ECS” than the previous generation of models, he said.

Less adaptation time

“A higher ECS means a greater likelihood of reaching higher levels of global warming, even with deeper emissions cuts”, Boucher and two British scientists − Professor Stephen Belcher and Professor Rowan Sutton from the UK National Centre for Atmospheric Science − wrote in a blog earlier this year.

“Higher warming would allow less time to adapt and mean a greater likelihood of passing climate ‘tipping points’ such as thawing of permafrost, which would further accelerate warming.”

“Unfortunately, our global failure to implement meaningful action on climate change over recent decades has put us in a situation where what we need to do to keep warming to safe levels is extremely simple”, said Dr Rogelj.

“Global greenhouse gas emissions need to decline today rather than tomorrow, and global CO2 emissions should be brought to net zero.” − Climate News Network

Fracking’s methane leaks drive climate heat

One likely cause of the inexorable rise in global heat is fracking’s methane leaks from the shale gas industry.

LONDON, 14 August, 2019 − An atmospheric methane rise that will speed up global temperature rise is probably being caused mainly by the gas industry’s fracking methane leaks in North America, a new study says.

The analysis, confirming environmentalists’ worst fears about fracking, is a serious blow to the industry, which claims the gas it produces is cleaner than coal and is needed in the interim before renewables can replace fossil fuels.

The study is the work of a scientist from Cornell University in the US who has examined the rapid rise in methane concentrations in the atmosphere since 2008. He has found that the gas’s carbon composition has changed.

His research suggests that methane from biological sources such as cows and bogs has less carbon-13 relative to carbon-12 (denoting the weight of the carbon atom at the centre of the methane molecule) than does methane from conventional natural gas and other fossil fuels such as coal.

The conclusion is that the process of forcing chemicals and water into rock to release gas – the process known as fracking – causes the increased methane emissions. The fracking industry has boomed, and the “signature” of the carbon in the atmosphere points directly to that as the cause.

“If we can stop pouring methane into the atmosphere, it will dissipate. It goes away pretty quickly. It’s the low-hanging fruit to slow global warming”

The scientist, Robert Howarth, professor of ecology and environmental biology at Cornell, said: “This recent increase in methane is massive. It’s globally significant. It’s contributed to some of the increase in global warming we’ve seen, and shale gas is a major player.” His study is published in Biogeosciences, a journal of the European Geosciences Union.

Professor Howarth said about two thirds of all new gas production over the last decade had been shale gas from the US and Canada. Previous studies had concluded erroneously that biological sources were the cause of rising methane, but the analysis of the gas showed it came from fracking.

Atmospheric methane levels rose during the last two decades of the 20th century but then levelled off for about a decade. Then they increased dramatically from 2008 to 2014, from about 570 teragrams (570 billion tonnes) annually to about 595 teragrams, because of global human-caused methane emissions in the last 11 years.

Methane is an intense but short-lived contributor to climate change. It traps heat in the atmosphere far more efficiently than carbon dioxide can, but over a much shorter period, because it breaks down quickly and can disperse completely in a few years.

Industry hopes dashed

Professor Howarth says: “If we can stop pouring methane into the atmosphere, it will dissipate. It goes away pretty quickly, compared to carbon dioxide. It’s the low-hanging fruit to slow global warming.”

The findings will be a serious blow to the hopes of the fracking industry to expand into Europe and other parts of the world. Already there is considerable resistance to fracking, and it has been banned in some EU countries, including France, Germany and Ireland.

But others − including the United Kingdom, which has recently declared a climate emergency − have encouraged fracking, despite growing public opposition.

The fact that fracking is now suspected of causing climate change to accelerate will make it extremely hard for governments to continue to encourage the industry. − Climate News Network

One likely cause of the inexorable rise in global heat is fracking’s methane leaks from the shale gas industry.

LONDON, 14 August, 2019 − An atmospheric methane rise that will speed up global temperature rise is probably being caused mainly by the gas industry’s fracking methane leaks in North America, a new study says.

The analysis, confirming environmentalists’ worst fears about fracking, is a serious blow to the industry, which claims the gas it produces is cleaner than coal and is needed in the interim before renewables can replace fossil fuels.

The study is the work of a scientist from Cornell University in the US who has examined the rapid rise in methane concentrations in the atmosphere since 2008. He has found that the gas’s carbon composition has changed.

His research suggests that methane from biological sources such as cows and bogs has less carbon-13 relative to carbon-12 (denoting the weight of the carbon atom at the centre of the methane molecule) than does methane from conventional natural gas and other fossil fuels such as coal.

The conclusion is that the process of forcing chemicals and water into rock to release gas – the process known as fracking – causes the increased methane emissions. The fracking industry has boomed, and the “signature” of the carbon in the atmosphere points directly to that as the cause.

“If we can stop pouring methane into the atmosphere, it will dissipate. It goes away pretty quickly. It’s the low-hanging fruit to slow global warming”

The scientist, Robert Howarth, professor of ecology and environmental biology at Cornell, said: “This recent increase in methane is massive. It’s globally significant. It’s contributed to some of the increase in global warming we’ve seen, and shale gas is a major player.” His study is published in Biogeosciences, a journal of the European Geosciences Union.

Professor Howarth said about two thirds of all new gas production over the last decade had been shale gas from the US and Canada. Previous studies had concluded erroneously that biological sources were the cause of rising methane, but the analysis of the gas showed it came from fracking.

Atmospheric methane levels rose during the last two decades of the 20th century but then levelled off for about a decade. Then they increased dramatically from 2008 to 2014, from about 570 teragrams (570 billion tonnes) annually to about 595 teragrams, because of global human-caused methane emissions in the last 11 years.

Methane is an intense but short-lived contributor to climate change. It traps heat in the atmosphere far more efficiently than carbon dioxide can, but over a much shorter period, because it breaks down quickly and can disperse completely in a few years.

Industry hopes dashed

Professor Howarth says: “If we can stop pouring methane into the atmosphere, it will dissipate. It goes away pretty quickly, compared to carbon dioxide. It’s the low-hanging fruit to slow global warming.”

The findings will be a serious blow to the hopes of the fracking industry to expand into Europe and other parts of the world. Already there is considerable resistance to fracking, and it has been banned in some EU countries, including France, Germany and Ireland.

But others − including the United Kingdom, which has recently declared a climate emergency − have encouraged fracking, despite growing public opposition.

The fact that fracking is now suspected of causing climate change to accelerate will make it extremely hard for governments to continue to encourage the industry. − Climate News Network

Artificial snow could save world’s coasts

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

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

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

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

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

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

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

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

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

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

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

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

3°C rise possible

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

3°C rise possible

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

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

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

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

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

Acid oceans may trigger mass extinction

A stable carbon cycle means life goes on. Too much carbon could wipe out many species. And acid oceans could hold the key.

LONDON, 23 July, 2019 − Catastrophically widespread die-offs of many creatures could be inevitable if human activities continue to lead to more acid oceans, a new study suggests.

Mass extinction may not be an enduring mystery. Instead, it may be an intrinsic property of the carbon cycle. Once levels of dissolved carbon dioxide in the oceans reach a certain threshold, life undergoes dramatic and catastrophic change.

If a US mathematician is right – and his argument is based on statistical reasoning and the evidence in the marine sediments – then once the seas become too acidic for marine organisms to form carbonate shells, a cascade of extinction begins.

And, he warns, the “unusually strong but geologically brief duration” of manmade carbon dioxide increase in the oceans can be matched with slow but devastating extinctions in the past.

In short, human combustion of fossil fuels, combined with the destruction of the forests, could be building up to extinctions on a scale so colossal that they will be visible in the fossil record hundreds of millions of years from now.

After a certain point, the carbon cycle will take over and decide life’s direction. It happened many times long before the emergence of the human species, and it could happen again, according to a new study in the  Proceedings of the National Academy of Sciences.

“It’s a positive feedback. More carbon dioxide leads to more carbon dioxide. Is such a feedback enough to render the system unstable?”

“Once we are over the threshold, how we got there may not matter,” said Daniel Rothman of the Massachusetts Institute of Technology. “Once you get over it, you’re dealing with how the Earth works, and it goes on its own ride.”

Professor Rothman developed his hypothesis in 2017, in the journal Science Advances, after he analysed 31 changes in the makeup of carbonate sediments laid down over the last 542 million years, and connected five great extinctions not just with carbon dioxide levels but with the rate at which these increased.

He may be for the moment a lone voice in linking four of the five major extinctions with critical levels of oceanic acidification as a consequence of a carbon dioxide threshold. But climate scientists and palaeontologists have been looking at possible links between carbon and extinction for decades.

They have also repeatedly warned that humans are about to precipitate a sixth mass extinction, chiefly on the basis that we are destroying natural habitat and erasing the conditions in which millions of species – many of them still not identified – were once able to flourish.

The carbon factor

But climate change driven by ever-increasing atmospheric carbon dioxide levels – powered in turn by ever-increasing combustion of fossil fuels – has also been a factor.

Whatever the risk to species or ecosystems, biologists and conservationists have warned that climate change driven by global heating can only make things worse.

And the more carefully researchers have looked at evidence of earlier catastrophic extinctions, the more bygone climate change has revealed itself. What caused the most dramatic and unequivocal of these – the “great dying” at the close of the Permian – is still hotly debated, but atmospheric conditions in one form or another have been repeatedly invoked and researchers have repeatedly drawn lessons for today.

But arguments so far have settled on whether such extinctions are a consequence of slow but inexorable episodes of volcanic discharge or some other geological shift.

Forget the trigger

Professor Rothman’s point is that the trigger itself may not be the important thing: what decides the fate of life on Earth is the level of carbon in the oceans and the rate at which it increases.

Once levels of acidification in the upper ocean reach a certain critical threshold, life is in for major disruption. If marine creatures cannot form shells, they are at risk. But even more dangerously, shells sink to the ocean floor, effectively removing carbon from circulation.

If there are fewer calcifying organisms, then less carbon dioxide is removed from the atmosphere and oceans become even more acidic. A vicious cycle has begun.

“It’s a positive feedback,” Professor Rothman said. “More carbon dioxide leads to more carbon dioxide. The question, from a mathematical point of view is, is such a feedback enough to render the system unstable?”

Balance restored

In his mathematical model, once carbon levels reached a critical threshold, a cascade of positive feedbacks amplified the effect. Severe ocean acidification set in.

The effect was not permanent. After tens of thousands of years, the carbon cycle did slip back to equilibrium and life could evolve and adapt again.

Carbon is now entering the oceans at an unprecedented rate, over what – in geological terms – is a very brief timespan. If human-triggered greenhouse gas emissions cross a critical threshold, the consequences could be as severe as any of the previous mass extinctions.

“It’s difficult to know how things will end up, given what is happening today,” he said. “But we are probably close to a critical threshold. Any spike would reach its maximum after about 10,000 years. Hopefully, that would give us time to find a solution.” − Climate News Network

A stable carbon cycle means life goes on. Too much carbon could wipe out many species. And acid oceans could hold the key.

LONDON, 23 July, 2019 − Catastrophically widespread die-offs of many creatures could be inevitable if human activities continue to lead to more acid oceans, a new study suggests.

Mass extinction may not be an enduring mystery. Instead, it may be an intrinsic property of the carbon cycle. Once levels of dissolved carbon dioxide in the oceans reach a certain threshold, life undergoes dramatic and catastrophic change.

If a US mathematician is right – and his argument is based on statistical reasoning and the evidence in the marine sediments – then once the seas become too acidic for marine organisms to form carbonate shells, a cascade of extinction begins.

And, he warns, the “unusually strong but geologically brief duration” of manmade carbon dioxide increase in the oceans can be matched with slow but devastating extinctions in the past.

In short, human combustion of fossil fuels, combined with the destruction of the forests, could be building up to extinctions on a scale so colossal that they will be visible in the fossil record hundreds of millions of years from now.

After a certain point, the carbon cycle will take over and decide life’s direction. It happened many times long before the emergence of the human species, and it could happen again, according to a new study in the  Proceedings of the National Academy of Sciences.

“It’s a positive feedback. More carbon dioxide leads to more carbon dioxide. Is such a feedback enough to render the system unstable?”

“Once we are over the threshold, how we got there may not matter,” said Daniel Rothman of the Massachusetts Institute of Technology. “Once you get over it, you’re dealing with how the Earth works, and it goes on its own ride.”

Professor Rothman developed his hypothesis in 2017, in the journal Science Advances, after he analysed 31 changes in the makeup of carbonate sediments laid down over the last 542 million years, and connected five great extinctions not just with carbon dioxide levels but with the rate at which these increased.

He may be for the moment a lone voice in linking four of the five major extinctions with critical levels of oceanic acidification as a consequence of a carbon dioxide threshold. But climate scientists and palaeontologists have been looking at possible links between carbon and extinction for decades.

They have also repeatedly warned that humans are about to precipitate a sixth mass extinction, chiefly on the basis that we are destroying natural habitat and erasing the conditions in which millions of species – many of them still not identified – were once able to flourish.

The carbon factor

But climate change driven by ever-increasing atmospheric carbon dioxide levels – powered in turn by ever-increasing combustion of fossil fuels – has also been a factor.

Whatever the risk to species or ecosystems, biologists and conservationists have warned that climate change driven by global heating can only make things worse.

And the more carefully researchers have looked at evidence of earlier catastrophic extinctions, the more bygone climate change has revealed itself. What caused the most dramatic and unequivocal of these – the “great dying” at the close of the Permian – is still hotly debated, but atmospheric conditions in one form or another have been repeatedly invoked and researchers have repeatedly drawn lessons for today.

But arguments so far have settled on whether such extinctions are a consequence of slow but inexorable episodes of volcanic discharge or some other geological shift.

Forget the trigger

Professor Rothman’s point is that the trigger itself may not be the important thing: what decides the fate of life on Earth is the level of carbon in the oceans and the rate at which it increases.

Once levels of acidification in the upper ocean reach a certain critical threshold, life is in for major disruption. If marine creatures cannot form shells, they are at risk. But even more dangerously, shells sink to the ocean floor, effectively removing carbon from circulation.

If there are fewer calcifying organisms, then less carbon dioxide is removed from the atmosphere and oceans become even more acidic. A vicious cycle has begun.

“It’s a positive feedback,” Professor Rothman said. “More carbon dioxide leads to more carbon dioxide. The question, from a mathematical point of view is, is such a feedback enough to render the system unstable?”

Balance restored

In his mathematical model, once carbon levels reached a critical threshold, a cascade of positive feedbacks amplified the effect. Severe ocean acidification set in.

The effect was not permanent. After tens of thousands of years, the carbon cycle did slip back to equilibrium and life could evolve and adapt again.

Carbon is now entering the oceans at an unprecedented rate, over what – in geological terms – is a very brief timespan. If human-triggered greenhouse gas emissions cross a critical threshold, the consequences could be as severe as any of the previous mass extinctions.

“It’s difficult to know how things will end up, given what is happening today,” he said. “But we are probably close to a critical threshold. Any spike would reach its maximum after about 10,000 years. Hopefully, that would give us time to find a solution.” − Climate News Network

Planting more trees could cut carbon by 25%

Scientists now know where to start restoring the forests to soak up carbon and cool the planet, by planting more trees on unused land.

LONDON, 5 July, 2019 − Swiss scientists have identified an area roughly the size of the United States that could be newly shaded by planting more trees. If the world’s nations then protected these 9 million square kilometres  of canopy over unused land, the new global forest could in theory soak up enough carbon to reduce atmospheric greenhouse gas by an estimated 25%.

That is, the extent of new tree canopy would be enough to take the main driver of global heating back to conditions on Earth a century ago.

And a second study, released in the same week, identifies 100 million hectares of degraded or destroyed tropical forest in 15 countries where restoration could start right now – and 87% of these hectares are in biodiversity hotspots that hold high concentrations of species found nowhere else.

The global study of the space available for tree canopy is published in the journal Science. Researchers looked for land not used for agriculture or developed for human settlement. They excluded wetlands and grasslands already fulfilling important ecological functions.

Huge canopy increase

They left existing forests out of their calculations. And they identified enough degraded, wasted, or simply unused land to provide another 0.9 billion hectares – that is, 9 million square kilometres – of tree canopy.

Such new or restored forest could store 205 billion tonnes of carbon. This is about two-thirds of the 300 billion tonnes of extra carbon humans have pumped into the atmosphere since the start of the Industrial Revolution 200 years ago.

“We all knew that restoring forests could play a part in tackling climate change, but we didn’t really know how big the impact would be. Our study shows clearly that forest restoration is the best climate change solution available today,” said Tom Crowther of the Swiss Federal Institute of Technology, now known as ETH Zurich.

“But we must act quickly, as new forests will take decades to mature and achieve their full potential as a source of natural carbon storage.”

“Restoring forests is a must-do – and it’s doable”

Forecasts for the future start with the data available now: the Swiss team worked from a dataset of observations of 80,000 forests, and used mapping software to predict possible tree cover worldwide under current conditions.

The big unknown is: what will global heating and climate change do for future forest growth? If nations go on burning fossil fuels at the present rates, then parts of the world could begin to experience harsher conditions and by 2050 the area available for tree cover could have dwindled by 223 million hectares, much of this in the tropics.

Forests are an integral part of the answer to the climate crisis. But forests worldwide, and particularly in the tropics, are also vulnerable to extremes of heat and drought and windstorm that are likely to come with ever higher average temperatures.

Where and when and how nations act to restore forests involves political decisions that must be based on evidence. So researchers have for years been trying to establish the extent of the global tree inventory, and its variety.

Unrecorded forest

They have confirmed the importance and value of urban forests. They have identified huge areas of woodland  hitherto not mapped or recorded. They have tried to make an estimate of the number of trees on the planet and the rate at which they are being felled, grazed, burned, or even extinguished.

They have identified threats to tropical forests, monitored the increasing damage to or degradation of what are  supposed to be protected areas, much of them forested, and they have measured changes in forests as the temperatures rise.

Right now, the world has 5.5 billion hectares of forest or woodland with at least 10% and up to 100% of tree cover: altogether this adds up to 2.8bn hectares of canopy. It also has a challenge to get on with: the Bonn Challenge to extend national forest areas by 350 million hectares by 2030 has been accepted by 48 countries so far.

The Swiss researchers calculated that there were up to 1.8 billion hectares of land of “low human activity” that could be reforested. If half of this was shaded by foliage, that would yield another 900 million hectares of canopy to soak up and store atmospheric carbon, and more than half of this potential tree space was in just six countries: Russia, the US, Canada, Australia, Brazil and China.

Best restoration options

But a second study, led by Brazilian scientists and published in the journal Science Advances, used high-resolution satellite studies to find that the most compelling opportunities for forest restoration exist in the lowland tropical rainforests of Central and South America, Africa and Southeast Asia.

Almost three-fourths of the restoration hotspots were in countries that had already made commitments under the Bonn Challenge. The five nations with the largest areas in need of restoration are Brazil, Indonesia, India, Madagascar and Colombia. Madagascar is also one of six African nations – the others are Rwanda, Uganda, Burundi, Togo and South Sudan – that, on average, offer the best immediate opportunities for forest restoration.

“Restoring tropical forests is fundamental to the planet’s health, now and for generations to come,” said Pedro Brancalion, of the University of Sao Paulo in Brazil, who led the study.

“For the first time, our study helps governments, investors and others seeking to restore global tropical moist forests to determine precise locations where restoring forests is most viable, enduring and beneficial. Restoring forests is a must-do – and it’s doable.” − Climate News Network

Scientists now know where to start restoring the forests to soak up carbon and cool the planet, by planting more trees on unused land.

LONDON, 5 July, 2019 − Swiss scientists have identified an area roughly the size of the United States that could be newly shaded by planting more trees. If the world’s nations then protected these 9 million square kilometres  of canopy over unused land, the new global forest could in theory soak up enough carbon to reduce atmospheric greenhouse gas by an estimated 25%.

That is, the extent of new tree canopy would be enough to take the main driver of global heating back to conditions on Earth a century ago.

And a second study, released in the same week, identifies 100 million hectares of degraded or destroyed tropical forest in 15 countries where restoration could start right now – and 87% of these hectares are in biodiversity hotspots that hold high concentrations of species found nowhere else.

The global study of the space available for tree canopy is published in the journal Science. Researchers looked for land not used for agriculture or developed for human settlement. They excluded wetlands and grasslands already fulfilling important ecological functions.

Huge canopy increase

They left existing forests out of their calculations. And they identified enough degraded, wasted, or simply unused land to provide another 0.9 billion hectares – that is, 9 million square kilometres – of tree canopy.

Such new or restored forest could store 205 billion tonnes of carbon. This is about two-thirds of the 300 billion tonnes of extra carbon humans have pumped into the atmosphere since the start of the Industrial Revolution 200 years ago.

“We all knew that restoring forests could play a part in tackling climate change, but we didn’t really know how big the impact would be. Our study shows clearly that forest restoration is the best climate change solution available today,” said Tom Crowther of the Swiss Federal Institute of Technology, now known as ETH Zurich.

“But we must act quickly, as new forests will take decades to mature and achieve their full potential as a source of natural carbon storage.”

“Restoring forests is a must-do – and it’s doable”

Forecasts for the future start with the data available now: the Swiss team worked from a dataset of observations of 80,000 forests, and used mapping software to predict possible tree cover worldwide under current conditions.

The big unknown is: what will global heating and climate change do for future forest growth? If nations go on burning fossil fuels at the present rates, then parts of the world could begin to experience harsher conditions and by 2050 the area available for tree cover could have dwindled by 223 million hectares, much of this in the tropics.

Forests are an integral part of the answer to the climate crisis. But forests worldwide, and particularly in the tropics, are also vulnerable to extremes of heat and drought and windstorm that are likely to come with ever higher average temperatures.

Where and when and how nations act to restore forests involves political decisions that must be based on evidence. So researchers have for years been trying to establish the extent of the global tree inventory, and its variety.

Unrecorded forest

They have confirmed the importance and value of urban forests. They have identified huge areas of woodland  hitherto not mapped or recorded. They have tried to make an estimate of the number of trees on the planet and the rate at which they are being felled, grazed, burned, or even extinguished.

They have identified threats to tropical forests, monitored the increasing damage to or degradation of what are  supposed to be protected areas, much of them forested, and they have measured changes in forests as the temperatures rise.

Right now, the world has 5.5 billion hectares of forest or woodland with at least 10% and up to 100% of tree cover: altogether this adds up to 2.8bn hectares of canopy. It also has a challenge to get on with: the Bonn Challenge to extend national forest areas by 350 million hectares by 2030 has been accepted by 48 countries so far.

The Swiss researchers calculated that there were up to 1.8 billion hectares of land of “low human activity” that could be reforested. If half of this was shaded by foliage, that would yield another 900 million hectares of canopy to soak up and store atmospheric carbon, and more than half of this potential tree space was in just six countries: Russia, the US, Canada, Australia, Brazil and China.

Best restoration options

But a second study, led by Brazilian scientists and published in the journal Science Advances, used high-resolution satellite studies to find that the most compelling opportunities for forest restoration exist in the lowland tropical rainforests of Central and South America, Africa and Southeast Asia.

Almost three-fourths of the restoration hotspots were in countries that had already made commitments under the Bonn Challenge. The five nations with the largest areas in need of restoration are Brazil, Indonesia, India, Madagascar and Colombia. Madagascar is also one of six African nations – the others are Rwanda, Uganda, Burundi, Togo and South Sudan – that, on average, offer the best immediate opportunities for forest restoration.

“Restoring tropical forests is fundamental to the planet’s health, now and for generations to come,” said Pedro Brancalion, of the University of Sao Paulo in Brazil, who led the study.

“For the first time, our study helps governments, investors and others seeking to restore global tropical moist forests to determine precise locations where restoring forests is most viable, enduring and beneficial. Restoring forests is a must-do – and it’s doable.” − Climate News Network