Author: Tim Radford

About Tim Radford

Tim Radford, a founding editor of Climate News Network, worked for The Guardian for 32 years, for most of that time as science editor. He has been covering climate change since 1988.

Global warming tips scales against the poor

The richest nations got richer through rising investment in fossil fuels – and the global warming they caused has made the poorest nations measurably poorer.

LONDON, 24 April, 2019 − Global warming has increased global economic inequality. Some countries have profited from climate change while the same rise in average planetary temperatures has dragged down economic growth in the warmer countries.

The gap between those groups of nations with the highest and lowest economic output per person is now around 25% larger than it would have been had there been no climate change.

“Our results show that most of the poorest countries on Earth are considerably poorer than they would have been without global warming,” said Noah Diffenbaugh, a climate scientist at Stanford University in California. “At the same time the majority of rich countries are richer than they would have been.”

He and his co-author, Marshall Burke, an earth system scientist at Stanford, report in the Proceedings of the National Academy of Sciences that they combed through 50 years of annual temperature readings and measurements of gross domestic product (GDP) for 165 nations, to tease out the effects of temperature fluctuation on economic growth.

“Many poor countries have been significantly harmed by the warming arising from wealthy countries’ energy consumption”

They found that during warmer than average years growth was accelerated in those nations with normally cool climates – such as Norway and Sweden – but was slowed significantly in those countries with tropical or subtropical climates such as India or Nigeria.

And between 1961 and 2010, they found that global warming depressed the wealth per person in the poorest nations by between 17% and 30%.

“The historical data clearly show that crops are more productive, people are healthier and we are more productive at work when temperatures are neither too hot nor too cold,” said Dr Burke. “This means that in cold countries, a little bit of warming can help. The opposite is true in places that are already hot.”

The two scientists put the message of climate injustice bluntly in their paper: “Our results show that, in addition to not sharing equally in the direct benefits of fossil fuel use, many poor countries have been significantly harmed by the warming arising from wealthy countries’ energy consumption.”

What if … ?

All such research is tortured by uncertainties, and none greater than what historians call counter-factual comparison: that is, what would have happened if global average temperatures had not risen by around 1°C in the last century.

To make their case, the researchers calculated 20,000 versions of what each separate country’s economic growth rate would have been without global warming, and based their estimates on the range of outcomes. So, they concede, there are uncertainties.

But their findings are in line with other separate studies. Geographers, economists and climate scientists have repeatedly pointed out that global warming consistently threatens the poorest people in any society and that economic inequalities tend to stoke conflict and drive migration while at the same time economic inequalities continue to ensure that the poorest will suffer even more.

And national studies of specific climate events have confirmed the link between temperature and output. Dr Burke has in an earlier study separately made the connection between rising temperatures and social conflict, and the Stanford two have already argued that even a small reduction in global warming would return huge economic benefits.

Renewable remedy

In effect, the latest research provides a kind of national climate audit. If greenhouse emissions are a measure of economic output, then the richest 10% produce atmospheric carbon dioxide almost as much as the bottom 90% together.

The Stanford study offers an estimate of the costs and benefits the richest and poorest have borne as a consequence of emissions. It also makes it clear that the poorer nations would benefit more from investment in renewable energy: that is, they could create more wealth in ways that did not intensify costly climate change.

“Our study makes the first accounting of exactly how much each country has been impacted economically by global warming, relative to historical greenhouse gas emissions,” said Professor Diffenbaugh.

“Historically, rapid economic development has been powered by fossil fuels. Our finding that global warming has exacerbated economic inequality suggests that there is an added economic benefit of energy sources that don’t contribute to further warming.” − Climate News Network

The richest nations got richer through rising investment in fossil fuels – and the global warming they caused has made the poorest nations measurably poorer.

LONDON, 24 April, 2019 − Global warming has increased global economic inequality. Some countries have profited from climate change while the same rise in average planetary temperatures has dragged down economic growth in the warmer countries.

The gap between those groups of nations with the highest and lowest economic output per person is now around 25% larger than it would have been had there been no climate change.

“Our results show that most of the poorest countries on Earth are considerably poorer than they would have been without global warming,” said Noah Diffenbaugh, a climate scientist at Stanford University in California. “At the same time the majority of rich countries are richer than they would have been.”

He and his co-author, Marshall Burke, an earth system scientist at Stanford, report in the Proceedings of the National Academy of Sciences that they combed through 50 years of annual temperature readings and measurements of gross domestic product (GDP) for 165 nations, to tease out the effects of temperature fluctuation on economic growth.

“Many poor countries have been significantly harmed by the warming arising from wealthy countries’ energy consumption”

They found that during warmer than average years growth was accelerated in those nations with normally cool climates – such as Norway and Sweden – but was slowed significantly in those countries with tropical or subtropical climates such as India or Nigeria.

And between 1961 and 2010, they found that global warming depressed the wealth per person in the poorest nations by between 17% and 30%.

“The historical data clearly show that crops are more productive, people are healthier and we are more productive at work when temperatures are neither too hot nor too cold,” said Dr Burke. “This means that in cold countries, a little bit of warming can help. The opposite is true in places that are already hot.”

The two scientists put the message of climate injustice bluntly in their paper: “Our results show that, in addition to not sharing equally in the direct benefits of fossil fuel use, many poor countries have been significantly harmed by the warming arising from wealthy countries’ energy consumption.”

What if … ?

All such research is tortured by uncertainties, and none greater than what historians call counter-factual comparison: that is, what would have happened if global average temperatures had not risen by around 1°C in the last century.

To make their case, the researchers calculated 20,000 versions of what each separate country’s economic growth rate would have been without global warming, and based their estimates on the range of outcomes. So, they concede, there are uncertainties.

But their findings are in line with other separate studies. Geographers, economists and climate scientists have repeatedly pointed out that global warming consistently threatens the poorest people in any society and that economic inequalities tend to stoke conflict and drive migration while at the same time economic inequalities continue to ensure that the poorest will suffer even more.

And national studies of specific climate events have confirmed the link between temperature and output. Dr Burke has in an earlier study separately made the connection between rising temperatures and social conflict, and the Stanford two have already argued that even a small reduction in global warming would return huge economic benefits.

Renewable remedy

In effect, the latest research provides a kind of national climate audit. If greenhouse emissions are a measure of economic output, then the richest 10% produce atmospheric carbon dioxide almost as much as the bottom 90% together.

The Stanford study offers an estimate of the costs and benefits the richest and poorest have borne as a consequence of emissions. It also makes it clear that the poorer nations would benefit more from investment in renewable energy: that is, they could create more wealth in ways that did not intensify costly climate change.

“Our study makes the first accounting of exactly how much each country has been impacted economically by global warming, relative to historical greenhouse gas emissions,” said Professor Diffenbaugh.

“Historically, rapid economic development has been powered by fossil fuels. Our finding that global warming has exacerbated economic inequality suggests that there is an added economic benefit of energy sources that don’t contribute to further warming.” − Climate News Network

Cloud forests risk drying out by 2060

For the world’s cloud forests, the future is overcast. Some face fiercer storm and flood: they could even lose their unique clouds.

LONDON, 23 April, 2019 – Planet Earth may be about to lose a whole ecosystem: the cloud forests – those species-rich, high altitude rainforests found mostly in Central and South America – could be all but gone in 40 years.

Researchers warn that within 25 years, global warming driven by ever increasing use of fossil fuels could dry up 60-80% of the misty mountain forests of Mexico, Puerto Rico, Costa Rica, Ecuador and Peru, simply by dispersing the clouds that keep them ever moist, and rich with plant, insect and bird life.

And as the habitat alters, that could be it for the Monarch butterflies that migrate in their millions to the mountains of Mexico, the elfin woods warbler found only in Puerto Rico, and the other creatures that make their homes in forests so rich and wet that even the trees are home to yet more green habitat: ferns, lichens, mosses and other epiphytes nourished by year-round water and water vapour.

And the reason? The clouds will have dispersed, or moved uphill, or simply been blown away as greenhouse gas ratios in the atmosphere continue to grow and temperatures creep ever higher, according to new research in the Public Library of Science journal PLOS One.

“Maria is more extreme in its precipitation than anything else the island has ever seen. I just didn’t expect that it was going to be so much more than anything else that has happened in the last 60 years”

And if nations go on burning ever greater quantities of coal, oil and natural gas to power economic growth, then the cloud and frost that keep the equatorial cloud forests unique homes to living things will have gone.

Nine-tenths of the cloud forests in the Western Hemisphere will have been lost by 2060, if the calculations funded by the US Department of Agriculture’s Forest Service are correct.

Researchers mapped cloud forest across the Western Hemisphere with data collected over the last 60 years and then used climate simulations to see how the habitat would change with time.

They found that indeed some regions would become even more immersed in cloud: this however would only add up to perhaps 1%. For the most part the clouds would thin, the steady supply of moisture would thin, and the forests would begin to change inexorably.

Trees head uphill

This is not the first research to suggest that ever higher temperatures would affect cloud patterns. Scientists using a different approach reported earlier this year that tropical cloud formation of the kind that damps down equatorial temperatures could be at risk.

Other researchers have used historic data to record the steady uphill march of characteristic trees in the Andean forests in response to average global temperature increases of 1°C in the past century.

And yet another team has warned that the increasingly violent winds that arrived in Puerto Rico with Hurricane Maria in 2017 would in any case change the make-up of forest species.

Devastating winds that uproot forest giants at all altitudes won’t be the only problem for the climate-hit forests and the region. Hurricane Maria dumped an unprecedented 1.029 mm of rain in a day on Puerto Rico.

Recurrence likely

A second study from the American Geophysical Union has confirmed that the extreme rainfall that accompanied Maria was not only the worst in the last 60 years, but has become much more likely to happen again.

Thanks to global warming, which increased the capacity of the atmosphere to absorb moisture, such floods are now five times more likely, they write in the journal Geophysical Research Letters.

“Maria is more extreme in its precipitation than anything else the island has ever seen,” said David Keellings of the University of Alabama, one of the authors.

“I just didn’t expect that it was going to be so much more than anything else that has happened in the last 60 years.” – Climate News Network

For the world’s cloud forests, the future is overcast. Some face fiercer storm and flood: they could even lose their unique clouds.

LONDON, 23 April, 2019 – Planet Earth may be about to lose a whole ecosystem: the cloud forests – those species-rich, high altitude rainforests found mostly in Central and South America – could be all but gone in 40 years.

Researchers warn that within 25 years, global warming driven by ever increasing use of fossil fuels could dry up 60-80% of the misty mountain forests of Mexico, Puerto Rico, Costa Rica, Ecuador and Peru, simply by dispersing the clouds that keep them ever moist, and rich with plant, insect and bird life.

And as the habitat alters, that could be it for the Monarch butterflies that migrate in their millions to the mountains of Mexico, the elfin woods warbler found only in Puerto Rico, and the other creatures that make their homes in forests so rich and wet that even the trees are home to yet more green habitat: ferns, lichens, mosses and other epiphytes nourished by year-round water and water vapour.

And the reason? The clouds will have dispersed, or moved uphill, or simply been blown away as greenhouse gas ratios in the atmosphere continue to grow and temperatures creep ever higher, according to new research in the Public Library of Science journal PLOS One.

“Maria is more extreme in its precipitation than anything else the island has ever seen. I just didn’t expect that it was going to be so much more than anything else that has happened in the last 60 years”

And if nations go on burning ever greater quantities of coal, oil and natural gas to power economic growth, then the cloud and frost that keep the equatorial cloud forests unique homes to living things will have gone.

Nine-tenths of the cloud forests in the Western Hemisphere will have been lost by 2060, if the calculations funded by the US Department of Agriculture’s Forest Service are correct.

Researchers mapped cloud forest across the Western Hemisphere with data collected over the last 60 years and then used climate simulations to see how the habitat would change with time.

They found that indeed some regions would become even more immersed in cloud: this however would only add up to perhaps 1%. For the most part the clouds would thin, the steady supply of moisture would thin, and the forests would begin to change inexorably.

Trees head uphill

This is not the first research to suggest that ever higher temperatures would affect cloud patterns. Scientists using a different approach reported earlier this year that tropical cloud formation of the kind that damps down equatorial temperatures could be at risk.

Other researchers have used historic data to record the steady uphill march of characteristic trees in the Andean forests in response to average global temperature increases of 1°C in the past century.

And yet another team has warned that the increasingly violent winds that arrived in Puerto Rico with Hurricane Maria in 2017 would in any case change the make-up of forest species.

Devastating winds that uproot forest giants at all altitudes won’t be the only problem for the climate-hit forests and the region. Hurricane Maria dumped an unprecedented 1.029 mm of rain in a day on Puerto Rico.

Recurrence likely

A second study from the American Geophysical Union has confirmed that the extreme rainfall that accompanied Maria was not only the worst in the last 60 years, but has become much more likely to happen again.

Thanks to global warming, which increased the capacity of the atmosphere to absorb moisture, such floods are now five times more likely, they write in the journal Geophysical Research Letters.

“Maria is more extreme in its precipitation than anything else the island has ever seen,” said David Keellings of the University of Alabama, one of the authors.

“I just didn’t expect that it was going to be so much more than anything else that has happened in the last 60 years.” – Climate News Network

Arctic leaks of laughing gas may add to heat

Laughing gas from the thawing Alaskan permafrost is no laughing matter. Nitrous oxide is one of the most potent greenhouse gases.

LONDON, 22 April, 2019 − US scientists have identified yet another hazard linked to the thawing permafrost: laughing gas. A series of flights over the North Slope of Alaska has detected unexpected levels of emissions of the greenhouse gas nitrous oxide from the rapidly warming soils.

Nitrous oxide, which chemists know also as laughing gas, is an estimated 300 times more potent as a climate warming agent than the principal greenhouse gas, carbon dioxide. It was present in data recordings at levels at least 12 times higher than all previous estimates.

And it is long-lived: it survives in the atmosphere for around 120 years, according to a separate new study of the microbiology of nitrous oxide. And if it gets even higher, into the stratosphere, it can be converted by the action of oxygen and sunlight into another oxide of nitrogen, to quietly destroy the ozone layer.

Oxides of nitrogen are at least as damaging to stratospheric ozone – an invisible screen that absorbs potentially lethal ultraviolet radiation from the sun – as the man-made chlorofluorocarbons banned by an international protocol three decades ago.

“Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2 would cause”

Nitrogen is an inert gas which makes up almost four-fifths of the planet’s atmosphere. It is vital to life: growing plants build their tissues by absorbing carbon dioxide from the atmosphere with the aid of photosynthesis. But they must also absorb nitrogen from plant decay and animal waste, through their roots, with help from soil microbes.

The process is natural, but too slow to help deliver the cereals, tubers and pulses needed to feed seven billion humans and their livestock. For more than 100 years, nations have been making nitrogenous fertiliser in factories and applying it generously to soils to boost harvest yields.

As a consequence, nitrous oxide is now the third most significant greenhouse gas, and the news that it is rising from the permafrost could be troubling.

The permafrost is home to enormous stores of carbon: as soil microbes become warmer and more active, they start to break down long-frozen and partly-decomposed plant material to release both carbon dioxide and potent quantities of methane. The implication is that nitrous oxide could add to the mix, and accelerate warming still further.

Study’s revelation

“Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2 would cause,” said Jordan Wilkerson, a Harvard graduate student who led the research, now published in the journal Atmospheric Chemistry and Physics.

“We don’t know how much more it’s going to increase and we didn’t know it was significant at all until this study came out.”

The research is based on data collected from a series of low-level flights over four different areas of the North Slope of Alaska, and the scientists used a routine technique to determine the balance of gases getting into the atmosphere from what had once been permafrost.

The point of the flights was to measure levels of carbon dioxide, methane and water vapour, but the raw data included information about nitrous oxide as well: information recovered and examined only years later.

Arctic in change

The weight of the finding is uncertain. One-fourth of the northern hemisphere is home to permafrost – 23 million square kilometres − and the flights covered only 310 square kilometres in all, and only in the month of August. What could be true for one part of the frozen landscape may not apply to all of it.

And thanks to global warming driven by fossil fuel emissions from the world’s power stations, vehicle exhausts and factory chimneys, the Arctic is changing.

Shrubs and trees are beginning to invade the frozen north. Green things consume nitrogen, and the greening of the Arctic might actually decrease nitrous oxide emissions.

Once again, the study is a reminder of how much more work is needed to understand the chemistry, biology and geophysics of climate change. − Climate News Network

Laughing gas from the thawing Alaskan permafrost is no laughing matter. Nitrous oxide is one of the most potent greenhouse gases.

LONDON, 22 April, 2019 − US scientists have identified yet another hazard linked to the thawing permafrost: laughing gas. A series of flights over the North Slope of Alaska has detected unexpected levels of emissions of the greenhouse gas nitrous oxide from the rapidly warming soils.

Nitrous oxide, which chemists know also as laughing gas, is an estimated 300 times more potent as a climate warming agent than the principal greenhouse gas, carbon dioxide. It was present in data recordings at levels at least 12 times higher than all previous estimates.

And it is long-lived: it survives in the atmosphere for around 120 years, according to a separate new study of the microbiology of nitrous oxide. And if it gets even higher, into the stratosphere, it can be converted by the action of oxygen and sunlight into another oxide of nitrogen, to quietly destroy the ozone layer.

Oxides of nitrogen are at least as damaging to stratospheric ozone – an invisible screen that absorbs potentially lethal ultraviolet radiation from the sun – as the man-made chlorofluorocarbons banned by an international protocol three decades ago.

“Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2 would cause”

Nitrogen is an inert gas which makes up almost four-fifths of the planet’s atmosphere. It is vital to life: growing plants build their tissues by absorbing carbon dioxide from the atmosphere with the aid of photosynthesis. But they must also absorb nitrogen from plant decay and animal waste, through their roots, with help from soil microbes.

The process is natural, but too slow to help deliver the cereals, tubers and pulses needed to feed seven billion humans and their livestock. For more than 100 years, nations have been making nitrogenous fertiliser in factories and applying it generously to soils to boost harvest yields.

As a consequence, nitrous oxide is now the third most significant greenhouse gas, and the news that it is rising from the permafrost could be troubling.

The permafrost is home to enormous stores of carbon: as soil microbes become warmer and more active, they start to break down long-frozen and partly-decomposed plant material to release both carbon dioxide and potent quantities of methane. The implication is that nitrous oxide could add to the mix, and accelerate warming still further.

Study’s revelation

“Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2 would cause,” said Jordan Wilkerson, a Harvard graduate student who led the research, now published in the journal Atmospheric Chemistry and Physics.

“We don’t know how much more it’s going to increase and we didn’t know it was significant at all until this study came out.”

The research is based on data collected from a series of low-level flights over four different areas of the North Slope of Alaska, and the scientists used a routine technique to determine the balance of gases getting into the atmosphere from what had once been permafrost.

The point of the flights was to measure levels of carbon dioxide, methane and water vapour, but the raw data included information about nitrous oxide as well: information recovered and examined only years later.

Arctic in change

The weight of the finding is uncertain. One-fourth of the northern hemisphere is home to permafrost – 23 million square kilometres − and the flights covered only 310 square kilometres in all, and only in the month of August. What could be true for one part of the frozen landscape may not apply to all of it.

And thanks to global warming driven by fossil fuel emissions from the world’s power stations, vehicle exhausts and factory chimneys, the Arctic is changing.

Shrubs and trees are beginning to invade the frozen north. Green things consume nitrogen, and the greening of the Arctic might actually decrease nitrous oxide emissions.

Once again, the study is a reminder of how much more work is needed to understand the chemistry, biology and geophysics of climate change. − Climate News Network

Chemists can turn carbon dioxide into coal

Chemists can now in theory turn carbon dioxide back into coal and light and heat homes with transparent wood. The world has ample energy-saving ideas.

LONDON, 18 April, 2019 – Australian scientists have found a way to take carbon dioxide and turn it back into something like coal.

It is as if they had translated the hundred-million-year process of making fossil fuel – a natural process powered in the Carboniferous Era by immense amounts of time, massive pressures and huge temperatures – in a laboratory in a day.

They used liquid metal catalysts – a catalyst is a compound that can midwife chemical change without itself being changed – to convert a solution of carbon dioxide into solid flakes of carbon.

And in a second reminder of the high levels of ingenuity and invention at work in the world’s laboratories, as chemists, physicists, biologists and engineers confront the twin challenges of climate change and efficient use of renewable energy, Swedish scientists report that they know how to make timber transparent and heat-storing. That is, they have a way of fashioning wood that can transmit light, and at the same time insulate the building it illuminates.

It may be some time before any huge-scale investment finds a way of taking the greenhouse gas from the air to convert it to solid carbon that can then be buried: for the moment, the surest way of soaking up the emissions from car exhausts and power station chimneys is to restore and protect forests.

“We’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable”

But researchers from Melbourne and Sydney report in the journal Nature Communications that they developed a liquid-metal electrocatalyst that transforms gaseous CO2 directly into carbon-containing solids at room temperature.

They charged their cerium-oxide and liquid gallium catalyst with an electric current and introduced it to a beaker of carbon dioxide dissolved in an electrolyte liquid, to collect solid flakes of carbon, of a quality good enough to be used, they say, to make high performance capacitor electrodes.

“While we can’t literally turn back time, turning carbon dioxide and burying it back in the ground is a bit like rewinding the emissions clock,” said Torben Daeneke of the Royal Melbourne Institute of Technology, known as RMIT Melbourne.

“To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable. By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable.”

Hard to accomplish

This would be a first step in safely storing what had once been the atmospheric carbon dioxide that – thanks to humankind’s profligate use of fossil fuels for 200 years – drives global warming and potentially catastrophic climate change. Researchers have been wrestling with the idea of carbon capture technology for years.

They have also been pointing out, for years, that the carbon dioxide from power station emissions could be captured and recycled as the basis for the organic chemical industry, or even for fuel..

None of the technologies explored so far is nearing commercial or large-scale production. But researchers go on trying to find new ways to save energy by making the most of natural materials.

Three years ago Lars Berglund of the Royal Institute of Technology in Stockholm announced an optically transparent wood. He and colleagues took out the light-absorbing lignin from some balsa wood, treated it with acrylic and ended up with timber fabric that they could see through, somewhat hazily, but strong enough to bear a load.

New generation

And, his research colleague told a meeting of the American Chemical Society in Orlando, Florida in April, it can now do more. It can absorb and release heat, and it could even be made biodegradable.

It could be the fabric of a new generation of eco-friendly housing, with the addition of polyethylene glycol or PEG, a wood-friendly polymer that melts in the warmth, absorbing heat – but at night solidifies again, releasing heat. In effect, the timber becomes a solar battery.

“Back in 2016, we showed that transparent wood has excellent thermal-insulating properties compared with glass, combined with high optical transmittance. In this work, we tried to reduce the building energy consumption even more by incorporating a material that can absorb, store and release heat,” said Céline Montanari of the Stockholm institute.

“During a sunny day the material will absorb heat before it reaches the indoor space, and the indoors will be cooler than the outside. And at night, the reverse occurs – the PEG becomes solid and releases heat indoors so you can maintain a constant temperature in the house.” – Climate News Network

Chemists can now in theory turn carbon dioxide back into coal and light and heat homes with transparent wood. The world has ample energy-saving ideas.

LONDON, 18 April, 2019 – Australian scientists have found a way to take carbon dioxide and turn it back into something like coal.

It is as if they had translated the hundred-million-year process of making fossil fuel – a natural process powered in the Carboniferous Era by immense amounts of time, massive pressures and huge temperatures – in a laboratory in a day.

They used liquid metal catalysts – a catalyst is a compound that can midwife chemical change without itself being changed – to convert a solution of carbon dioxide into solid flakes of carbon.

And in a second reminder of the high levels of ingenuity and invention at work in the world’s laboratories, as chemists, physicists, biologists and engineers confront the twin challenges of climate change and efficient use of renewable energy, Swedish scientists report that they know how to make timber transparent and heat-storing. That is, they have a way of fashioning wood that can transmit light, and at the same time insulate the building it illuminates.

It may be some time before any huge-scale investment finds a way of taking the greenhouse gas from the air to convert it to solid carbon that can then be buried: for the moment, the surest way of soaking up the emissions from car exhausts and power station chimneys is to restore and protect forests.

“We’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable”

But researchers from Melbourne and Sydney report in the journal Nature Communications that they developed a liquid-metal electrocatalyst that transforms gaseous CO2 directly into carbon-containing solids at room temperature.

They charged their cerium-oxide and liquid gallium catalyst with an electric current and introduced it to a beaker of carbon dioxide dissolved in an electrolyte liquid, to collect solid flakes of carbon, of a quality good enough to be used, they say, to make high performance capacitor electrodes.

“While we can’t literally turn back time, turning carbon dioxide and burying it back in the ground is a bit like rewinding the emissions clock,” said Torben Daeneke of the Royal Melbourne Institute of Technology, known as RMIT Melbourne.

“To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable. By using liquid metals as a catalyst, we’ve shown it’s possible to turn the gas back into carbon at room temperature, in a process that’s efficient and scalable.”

Hard to accomplish

This would be a first step in safely storing what had once been the atmospheric carbon dioxide that – thanks to humankind’s profligate use of fossil fuels for 200 years – drives global warming and potentially catastrophic climate change. Researchers have been wrestling with the idea of carbon capture technology for years.

They have also been pointing out, for years, that the carbon dioxide from power station emissions could be captured and recycled as the basis for the organic chemical industry, or even for fuel..

None of the technologies explored so far is nearing commercial or large-scale production. But researchers go on trying to find new ways to save energy by making the most of natural materials.

Three years ago Lars Berglund of the Royal Institute of Technology in Stockholm announced an optically transparent wood. He and colleagues took out the light-absorbing lignin from some balsa wood, treated it with acrylic and ended up with timber fabric that they could see through, somewhat hazily, but strong enough to bear a load.

New generation

And, his research colleague told a meeting of the American Chemical Society in Orlando, Florida in April, it can now do more. It can absorb and release heat, and it could even be made biodegradable.

It could be the fabric of a new generation of eco-friendly housing, with the addition of polyethylene glycol or PEG, a wood-friendly polymer that melts in the warmth, absorbing heat – but at night solidifies again, releasing heat. In effect, the timber becomes a solar battery.

“Back in 2016, we showed that transparent wood has excellent thermal-insulating properties compared with glass, combined with high optical transmittance. In this work, we tried to reduce the building energy consumption even more by incorporating a material that can absorb, store and release heat,” said Céline Montanari of the Stockholm institute.

“During a sunny day the material will absorb heat before it reaches the indoor space, and the indoors will be cooler than the outside. And at night, the reverse occurs – the PEG becomes solid and releases heat indoors so you can maintain a constant temperature in the house.” – Climate News Network

Extreme heat is growing threat to harvests

A warmer world means more chance of extreme heat in more than one continent at the same time, and a rising threat to global food security.

LONDON, 17 April, 2019 − Ever-higher average global temperatures mean more intense extreme heat over ever-wider regions.

When the planet becomes on average 1.5°C warmer than it was for most of human history, then for two out of every three years, one-fourth of the northern hemisphere will experience the kind of blistering heat waves recorded in 2018.

And should planetary average temperatures creep up by 2°C – the maximum proposed by 195 nations at the global climate conference in Paris in 2015 – then the probability rises to 100%. That is, extreme heat over a large area of the hemisphere will be guaranteed every summer.

Heat extremes are all too often accompanied by devastating thunderstorms or extended drought and massive outbreaks of wildfire, with potentially disastrous consequences for harvests in the blighted regions.

“Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland”

In 2018, people died of heatstroke, roads and even rails started to melt, forests went up in flames, and power generation systems sometimes failed, not just in one region but in a number in the temperate zones and the Arctic at the same time.

Between May and July, 22% of agricultural land and crowded cities of the northern half of the globe were hit simultaneously by extended periods of extreme heat. In all, 17 countries were affected, from Canada and the US across the Atlantic and Pacific to Russia, Japan and South Korea. In Europe, temperatures in the rivers Rhine and Elbe reached such heights that fish suffocated; there were wildfires in Sweden, Latvia and Greece and record temperatures in Germany.

“Without climate change that can be explained by human activity, we wouldn’t have such a large area being simultaneously affected by heat as we did in 2018,” said Martha Vogel, of the Swiss Federal Institute of Technology, known as ETH Zurich, who presented her findings at a press conference held by the European Geosciences Union in Vienna.

Serious impacts

The reasoning and methodology have yet to be published, but the authors say their paper is in review for the journal Earth’s Future. “If in future more and more key agricultural regions and densely populated areas are affected by simultaneous heatwaves, this would have severe consequences.”

Other research teams have already warned that global warming could bring a repeat of the simultaneous drought and heat outbreaks across the world that triggered calamitous famines in Asia and Africa between 1875 and 1878.

They have repeatedly warned of potentially catastrophic levels of heat that could arrive with increasing frequency to claim greater numbers of lives especially when accompanied by extreme levels of humidity.

The Swiss scientists focussed on data from agricultural regions and busy urban areas above latitude 30° for the years 1958 to 2018 to find occasions of heat extremes in more than one region and then used computer modelling to simulate probabilities as average planetary temperatures continued to grow.

Poor are hardest-hit

The choice of agricultural areas was purposeful: in such scenarios where more than one region suffers harvest failures, food prices begin to soar. In the 2010 heatwave, Russia ended all its wheat exports and prices in Pakistan rose by 16%, with harsh consequences for the poorest. Governments, agriculture ministries and international aid agencies need to be prepared.

“Such incidents cannot be resolved by individual countries acting on their own. Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland,” said Sonia Seneviratne, an ETH climate scientist who has also shared in the study.

“We are already clearly feeling the effects just from the one degree that global average temperature has risen since the pre-industrial era.” − Climate News Network

A warmer world means more chance of extreme heat in more than one continent at the same time, and a rising threat to global food security.

LONDON, 17 April, 2019 − Ever-higher average global temperatures mean more intense extreme heat over ever-wider regions.

When the planet becomes on average 1.5°C warmer than it was for most of human history, then for two out of every three years, one-fourth of the northern hemisphere will experience the kind of blistering heat waves recorded in 2018.

And should planetary average temperatures creep up by 2°C – the maximum proposed by 195 nations at the global climate conference in Paris in 2015 – then the probability rises to 100%. That is, extreme heat over a large area of the hemisphere will be guaranteed every summer.

Heat extremes are all too often accompanied by devastating thunderstorms or extended drought and massive outbreaks of wildfire, with potentially disastrous consequences for harvests in the blighted regions.

“Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland”

In 2018, people died of heatstroke, roads and even rails started to melt, forests went up in flames, and power generation systems sometimes failed, not just in one region but in a number in the temperate zones and the Arctic at the same time.

Between May and July, 22% of agricultural land and crowded cities of the northern half of the globe were hit simultaneously by extended periods of extreme heat. In all, 17 countries were affected, from Canada and the US across the Atlantic and Pacific to Russia, Japan and South Korea. In Europe, temperatures in the rivers Rhine and Elbe reached such heights that fish suffocated; there were wildfires in Sweden, Latvia and Greece and record temperatures in Germany.

“Without climate change that can be explained by human activity, we wouldn’t have such a large area being simultaneously affected by heat as we did in 2018,” said Martha Vogel, of the Swiss Federal Institute of Technology, known as ETH Zurich, who presented her findings at a press conference held by the European Geosciences Union in Vienna.

Serious impacts

The reasoning and methodology have yet to be published, but the authors say their paper is in review for the journal Earth’s Future. “If in future more and more key agricultural regions and densely populated areas are affected by simultaneous heatwaves, this would have severe consequences.”

Other research teams have already warned that global warming could bring a repeat of the simultaneous drought and heat outbreaks across the world that triggered calamitous famines in Asia and Africa between 1875 and 1878.

They have repeatedly warned of potentially catastrophic levels of heat that could arrive with increasing frequency to claim greater numbers of lives especially when accompanied by extreme levels of humidity.

The Swiss scientists focussed on data from agricultural regions and busy urban areas above latitude 30° for the years 1958 to 2018 to find occasions of heat extremes in more than one region and then used computer modelling to simulate probabilities as average planetary temperatures continued to grow.

Poor are hardest-hit

The choice of agricultural areas was purposeful: in such scenarios where more than one region suffers harvest failures, food prices begin to soar. In the 2010 heatwave, Russia ended all its wheat exports and prices in Pakistan rose by 16%, with harsh consequences for the poorest. Governments, agriculture ministries and international aid agencies need to be prepared.

“Such incidents cannot be resolved by individual countries acting on their own. Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland,” said Sonia Seneviratne, an ETH climate scientist who has also shared in the study.

“We are already clearly feeling the effects just from the one degree that global average temperature has risen since the pre-industrial era.” − Climate News Network

Restoring forests rules out growing crops

Restoring forests is helpful, but planting crops to do so is not. Only one of these options soaks up enough atmospheric carbon.

LONDON, 15 April, 2019 − Nations of the world are committed to restoring forests covering an area the size of India to soak up carbon dioxide and combat climate change. But British scientists have identified a serious flaw in the plan.

“Two-thirds of the area committed to global reforestation for carbon storage is slated to grow crops,” they write in the journal Nature. “This raises serious concerns.”

Their argument is simple. To limit global warming to no more than 1.5°C by the end of the century requires both rapid cuts in emissions of carbon dioxide from fossil fuel use, and investment in efficient ways of removing CO2 from the atmosphere.

Altogether 43 tropical and subtropical nations have pledged to restore 350 million hectares of forest to remove 42 billion tonnes of carbon from the atmosphere by 2100.

Little natural forest

Many of them, including Brazil, China and India, have already committed to 292 million hectares of new canopy. But in their analysis of the plans published so far, the scientists say that only 34% of this accumulated area would go back to natural forest.

Another 45% would be covered by plantations of one species harvested for biomass or timber, and 21% would be devoted to agroforestry: a mix of crops sheltered by stands of woodland.

In their calculations, this altogether would remove only 16 bn tonnes of carbon. That is because natural forests restored and subsequently protected would hold 40 times the carbon of a monoculture plantation and six times more than any mix of trees and crops.

“There is a scandal here,” said Simon Lewis, a geographer at University College London, who led the analysis. “To most people, forest restoration means bringing back natural forests, but policy makers are calling vast monocultures ‘forest restoration.’ And worse, the advertised climate benefits are absent.”

“To most people, forest restoration means bringing back natural forests, but policy makers are calling vast monocultures ‘forest restoration’”

Forests are only part of the answer to the challenge of containing climate change. To keep to the promise made by 195 nations in Paris in 2015, humankind has to find ways to remove 730 bn tonnes of CO2 from the atmosphere, which translates to 199 bn tonnes of carbon.

If the world found ways to boost the total area of global forest, woodland and woody savannahs, this could absorb perhaps a quarter of the total needed to keep planetary warming to no more than 1.5°C. And many countries have signed up to convert degraded land to new tree canopy.

“But will this policy work?” the scientists ask. “We show that under current plans, it will not. A closer look at countries’ reports reveals that almost half the pledged area is set to become plantations of commercial trees.”

Their point is that plantations can support local economies, but are poorer at storing carbon. Natural forests require little or no disturbance from humans, whereas the regular clearing and harvesting of plantations releases stored carbon dioxide back into the atmosphere every 10 or 20 years, while natural forests go on sequestering the greenhouse gas for decades. Natural regeneration is the cheapest and easiest option.

Land use shift

Most of the monoculture commitments are in large countries such as Brazil, China, Indonesia, Nigeria and the Democratic Republic of the Congo. The scientists suggest such plans have been insufficiently thought through. Drastic increases in tropical plantation for commercial crops would mark a major shift in global land use and could be accompanied by a fall in prices, with potentially unsatisfactory economic consequences.

And, they argue, policymakers are in any case misinterpreting the term forest restoration: it should not include plantations of a single species, such as eucalypt or rubber, which would do little for carbon sequestration. If commercial plantations were planted across the whole 350 million hectares, the entire crop would soak up and store just one billion tonnes of carbon.

“Of course new natural forests alone are not sufficient to meet our climate goals,” said Charlotte Wheeler of the University of Edinburgh, another of the authors. “Emissions from fossil fuels and deforestation must also stop.

“Other ways to remove carbon from the atmosphere are also needed. But no scenario has been produced that keeps climate change below dangerous levels without the large-scale restoration of natural forests.” − Climate News Network

Restoring forests is helpful, but planting crops to do so is not. Only one of these options soaks up enough atmospheric carbon.

LONDON, 15 April, 2019 − Nations of the world are committed to restoring forests covering an area the size of India to soak up carbon dioxide and combat climate change. But British scientists have identified a serious flaw in the plan.

“Two-thirds of the area committed to global reforestation for carbon storage is slated to grow crops,” they write in the journal Nature. “This raises serious concerns.”

Their argument is simple. To limit global warming to no more than 1.5°C by the end of the century requires both rapid cuts in emissions of carbon dioxide from fossil fuel use, and investment in efficient ways of removing CO2 from the atmosphere.

Altogether 43 tropical and subtropical nations have pledged to restore 350 million hectares of forest to remove 42 billion tonnes of carbon from the atmosphere by 2100.

Little natural forest

Many of them, including Brazil, China and India, have already committed to 292 million hectares of new canopy. But in their analysis of the plans published so far, the scientists say that only 34% of this accumulated area would go back to natural forest.

Another 45% would be covered by plantations of one species harvested for biomass or timber, and 21% would be devoted to agroforestry: a mix of crops sheltered by stands of woodland.

In their calculations, this altogether would remove only 16 bn tonnes of carbon. That is because natural forests restored and subsequently protected would hold 40 times the carbon of a monoculture plantation and six times more than any mix of trees and crops.

“There is a scandal here,” said Simon Lewis, a geographer at University College London, who led the analysis. “To most people, forest restoration means bringing back natural forests, but policy makers are calling vast monocultures ‘forest restoration.’ And worse, the advertised climate benefits are absent.”

“To most people, forest restoration means bringing back natural forests, but policy makers are calling vast monocultures ‘forest restoration’”

Forests are only part of the answer to the challenge of containing climate change. To keep to the promise made by 195 nations in Paris in 2015, humankind has to find ways to remove 730 bn tonnes of CO2 from the atmosphere, which translates to 199 bn tonnes of carbon.

If the world found ways to boost the total area of global forest, woodland and woody savannahs, this could absorb perhaps a quarter of the total needed to keep planetary warming to no more than 1.5°C. And many countries have signed up to convert degraded land to new tree canopy.

“But will this policy work?” the scientists ask. “We show that under current plans, it will not. A closer look at countries’ reports reveals that almost half the pledged area is set to become plantations of commercial trees.”

Their point is that plantations can support local economies, but are poorer at storing carbon. Natural forests require little or no disturbance from humans, whereas the regular clearing and harvesting of plantations releases stored carbon dioxide back into the atmosphere every 10 or 20 years, while natural forests go on sequestering the greenhouse gas for decades. Natural regeneration is the cheapest and easiest option.

Land use shift

Most of the monoculture commitments are in large countries such as Brazil, China, Indonesia, Nigeria and the Democratic Republic of the Congo. The scientists suggest such plans have been insufficiently thought through. Drastic increases in tropical plantation for commercial crops would mark a major shift in global land use and could be accompanied by a fall in prices, with potentially unsatisfactory economic consequences.

And, they argue, policymakers are in any case misinterpreting the term forest restoration: it should not include plantations of a single species, such as eucalypt or rubber, which would do little for carbon sequestration. If commercial plantations were planted across the whole 350 million hectares, the entire crop would soak up and store just one billion tonnes of carbon.

“Of course new natural forests alone are not sufficient to meet our climate goals,” said Charlotte Wheeler of the University of Edinburgh, another of the authors. “Emissions from fossil fuels and deforestation must also stop.

“Other ways to remove carbon from the atmosphere are also needed. But no scenario has been produced that keeps climate change below dangerous levels without the large-scale restoration of natural forests.” − Climate News Network

Glaciers’ global melt may leave Alps bare

High mountain ice is vital to millions. As the world warms, the glaciers’ global melt could see the frozen peaks vanish.

LONDON, 12 April, 2019 – Many of the planet’s most scenic – and most valued – high-altitude landscapes are likely to look quite different within the next 80 years: the glaciers’ global melt will have left just bare rock.

By the century’s end, Europe’s famous Alps – the chain of snow- and ice-covered peaks that have become a playground of the wealthy and a source of income and pleasure for generations – will have lost more than nine-tenths of all its glacier ice.

And in the last 50 years, the world’s glaciers – in Asia, the Americas, Europe, Africa and the sub-Arctic mountains – have lost more than nine trillion tonnes of ice as global temperatures creep ever upwards in response to profligate combustion of fossil fuels.

And as meltwater has trickled down the mountains, the seas have risen by 27mm, thanks entirely to glacial retreat.

“Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century”

In two separate studies, Swiss scientists have tried to audit a profit and loss account for the world’s frozen high-altitude rivers, and found a steady downhill trend.

Glacial ice is a source of security and even wealth: in the poorest regions the annual summer melt of winter snow and ice banked at altitude can guarantee both energy as hydropower and water for crops in the valleys and floodplains.

In wealthy regions, the white peaks and slopes become sources of income as tourist attractions and centres for winter sport – as well as reliable sources of power and water.

Swiss focus

In the journal The Cryosphere, a team from the Swiss Federal Institute of Technology, almost always known simply as ETH Zurich, looked into the future of the nation’s own landscape, and beyond.

They made computer models of the annual flow of ice and its melting patterns and took 2017 as the reference year: a year when the Alpine glaciers bore 100 cubic kilometres of ice. And then they started simulating the future.

If humankind kept the promise made by 195 nations in Paris in 2015, to drastically reduce fossil fuel use, lower emissions of carbon dioxide, restore the forests and keep global warming to no more than 2°C above historic levels, then the stores of high ice would be reduced by more than a third over the next eight decades. If humankind went on expanding its use of fossil fuels at the present rates, then half of all the ice would be lost by 2050 and 95% by 2100.

Time lag

But there will be losses in all scenarios: warming so far has seen to that. Ice reflects radiation and keeps itself cold, so change lags behind atmospheric temperature.

“The future evolution of glaciers will strongly depend on how the climate will evolve,” said Harry Zekollari, once of ETH and now at Delft University of Technology in the Netherlands, who led the research. “In the case of a more limited warming, a far more substantial part of the glaciers could be saved.”

The Alpine glaciers were made world-famous first by Romantic painters and poets of the 19th century, among them JMW Turner and Lord Byron. But their contribution to rising sea levels is, in a global context, negligible.

When Swiss researchers and their Russian, Canadian and European partners looked at the big picture, they found that the mass loss of ice from the mountains of AlaskaCanada, parts of Asia and the Andes matched the increasing flow of water from the melting Greenland ice cap, and exceeded the flow of melting water from the Antarctic continent.

Europe’s modest melt

They report in Nature that glaciers separate from the Greenland and Antarctic sheets covered 706,000 square kilometres of the planet, with a total volume of 170,000 cubic kilometres, or 40 centimetres of potential sea level rise.

And in the five decades from 1961 to 2016, according to careful study of satellite imagery and historic observations, the seas have already risen by 27mm as a consequence of increasing rates of glacial retreat. This is already between 25% and 30% of observed sea level rise so far.

Europe did not figure much in the reckoning. “Globally, we lose three times the ice volume stored in the entirety of the European Alps – every single year,” said Michael Zemp, a glaciologist at the University of Zurich.

He and his colleagues warn: “Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century, while heavily glacierised regions will continue to contribute to sea level rise beyond 2100.” – Climate News Network

High mountain ice is vital to millions. As the world warms, the glaciers’ global melt could see the frozen peaks vanish.

LONDON, 12 April, 2019 – Many of the planet’s most scenic – and most valued – high-altitude landscapes are likely to look quite different within the next 80 years: the glaciers’ global melt will have left just bare rock.

By the century’s end, Europe’s famous Alps – the chain of snow- and ice-covered peaks that have become a playground of the wealthy and a source of income and pleasure for generations – will have lost more than nine-tenths of all its glacier ice.

And in the last 50 years, the world’s glaciers – in Asia, the Americas, Europe, Africa and the sub-Arctic mountains – have lost more than nine trillion tonnes of ice as global temperatures creep ever upwards in response to profligate combustion of fossil fuels.

And as meltwater has trickled down the mountains, the seas have risen by 27mm, thanks entirely to glacial retreat.

“Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century”

In two separate studies, Swiss scientists have tried to audit a profit and loss account for the world’s frozen high-altitude rivers, and found a steady downhill trend.

Glacial ice is a source of security and even wealth: in the poorest regions the annual summer melt of winter snow and ice banked at altitude can guarantee both energy as hydropower and water for crops in the valleys and floodplains.

In wealthy regions, the white peaks and slopes become sources of income as tourist attractions and centres for winter sport – as well as reliable sources of power and water.

Swiss focus

In the journal The Cryosphere, a team from the Swiss Federal Institute of Technology, almost always known simply as ETH Zurich, looked into the future of the nation’s own landscape, and beyond.

They made computer models of the annual flow of ice and its melting patterns and took 2017 as the reference year: a year when the Alpine glaciers bore 100 cubic kilometres of ice. And then they started simulating the future.

If humankind kept the promise made by 195 nations in Paris in 2015, to drastically reduce fossil fuel use, lower emissions of carbon dioxide, restore the forests and keep global warming to no more than 2°C above historic levels, then the stores of high ice would be reduced by more than a third over the next eight decades. If humankind went on expanding its use of fossil fuels at the present rates, then half of all the ice would be lost by 2050 and 95% by 2100.

Time lag

But there will be losses in all scenarios: warming so far has seen to that. Ice reflects radiation and keeps itself cold, so change lags behind atmospheric temperature.

“The future evolution of glaciers will strongly depend on how the climate will evolve,” said Harry Zekollari, once of ETH and now at Delft University of Technology in the Netherlands, who led the research. “In the case of a more limited warming, a far more substantial part of the glaciers could be saved.”

The Alpine glaciers were made world-famous first by Romantic painters and poets of the 19th century, among them JMW Turner and Lord Byron. But their contribution to rising sea levels is, in a global context, negligible.

When Swiss researchers and their Russian, Canadian and European partners looked at the big picture, they found that the mass loss of ice from the mountains of AlaskaCanada, parts of Asia and the Andes matched the increasing flow of water from the melting Greenland ice cap, and exceeded the flow of melting water from the Antarctic continent.

Europe’s modest melt

They report in Nature that glaciers separate from the Greenland and Antarctic sheets covered 706,000 square kilometres of the planet, with a total volume of 170,000 cubic kilometres, or 40 centimetres of potential sea level rise.

And in the five decades from 1961 to 2016, according to careful study of satellite imagery and historic observations, the seas have already risen by 27mm as a consequence of increasing rates of glacial retreat. This is already between 25% and 30% of observed sea level rise so far.

Europe did not figure much in the reckoning. “Globally, we lose three times the ice volume stored in the entirety of the European Alps – every single year,” said Michael Zemp, a glaciologist at the University of Zurich.

He and his colleagues warn: “Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century, while heavily glacierised regions will continue to contribute to sea level rise beyond 2100.” – Climate News Network

Trees’ shade can cool cities by 5°C

Urban planners need more than just a leaf from nature’s book. To cool sweltering citizens they should exploit the whole woodland canopy and use the trees’ shade.

LONDON, 11 April, 2019 − Tomorrow’s sweltering cities could be tamed, thanks to their trees’ shade. Leafy figs and magnolias, beeches and birches, planes and chestnuts in the sterile tarmac and cement world of the great modern city could deliver canopies that could bring temperatures down by more than 5°C in the hottest of the heatwave summers.

And researchers now know this, not because they tested it with computer simulations, and not because they interpreted the radiation signal from satellite studies. They know it because one scientist fitted one bicycle with its own tiny weather station and took the temperature every five metres along 10 rides or transects, each along roughly seven kilometres of highly built-up city infrastructure.

To make sure of her readings, Carly Ziter of the University of Wisconsin-Madison repeated each ride between three and 12 times at different times of the day

And the conclusion: the city streets were hot as sunlight slammed down on the hard, impervious surfaces of street, pavement, flyover and square. But where there was green sward or shade from a tree, the temperature dropped.

“The trees we plant now or the areas we pave now are going to be determining the temperatures of our cities in the next century”

In those patches where two or more trees met and two-fifths of the sky was screened by foliage, the temperature dropped by an average of 3.5°C and sometimes − especially where the number of trees and their proximity delivered ever more shade − by up to 5.7°C.

Trees not only deliver shade, they transpire. That is, they exhale water through the stomata in their leaves and provide a second outdoor air-conditioning mechanism. The difference, too, between shade and sunlight temperatures can set up an air flow.

The results, reported in the Proceedings of the National Academy of Sciences, “suggest strategies for managing urban land-cover patterns to enhance resilience to cities’ warming.” In other words, trees are good things to plant, anywhere, but especially in the concrete jungle.

Once again, this is no surprise. Researchers have been looking at what might be called the green response to urban warming for years, and found that urban tree cover can add as much as $500m to the economies of the great cities.

Urban trees don’t just deliver shade, they can soak up atmospheric carbon in ways that match any rainforest giant, and the simple presence of trees in suburban roads can add appreciably to property values as well as simple amenity.

Hotter cities

And tomorrow’s cities will need help from the trees. More than half of the world’s population is already crammed into cities, and all cities are plagued by what is known as the urban heat island effect: that is, because of lighting, central heating, air conditioning, traffic, tarmac, tiles and slate, metro systems, and light industry, cities can be hotter than the surrounding countryside by 3°C or more.

With global warming so far on track to reach a global average of 3°C higher than at any time in human history by the century’s end – when cities will be even more crowded as population soars – city planners need a low-cost answer to what promises to be the serious and potentially lethal health hazard of ever more intense and prolonged heatwaves.

And not only do trees deliver cool shade: there is even research to suggest that they do better in the warmer cities. The Madison studies offer fine detail to something most city dwellers know intuitively. Cities need green spaces and tree-lined avenues. The next step is to work out how best to use such findings.

“It’s not really enough to just kind of go out and plant trees, we really need to think about how many we are planting and where we’re planting them. We’re not saying planting one tree does nothing, but you’re going to have a bigger effect if you plant a tree and your neighbour plants a tree and their neighbour plants a tree,” Dr Ziter said.

“The trees we plant now or the areas we pave now are going to be determining the temperatures of our cities in the next century.” − Climate News Network

Urban planners need more than just a leaf from nature’s book. To cool sweltering citizens they should exploit the whole woodland canopy and use the trees’ shade.

LONDON, 11 April, 2019 − Tomorrow’s sweltering cities could be tamed, thanks to their trees’ shade. Leafy figs and magnolias, beeches and birches, planes and chestnuts in the sterile tarmac and cement world of the great modern city could deliver canopies that could bring temperatures down by more than 5°C in the hottest of the heatwave summers.

And researchers now know this, not because they tested it with computer simulations, and not because they interpreted the radiation signal from satellite studies. They know it because one scientist fitted one bicycle with its own tiny weather station and took the temperature every five metres along 10 rides or transects, each along roughly seven kilometres of highly built-up city infrastructure.

To make sure of her readings, Carly Ziter of the University of Wisconsin-Madison repeated each ride between three and 12 times at different times of the day

And the conclusion: the city streets were hot as sunlight slammed down on the hard, impervious surfaces of street, pavement, flyover and square. But where there was green sward or shade from a tree, the temperature dropped.

“The trees we plant now or the areas we pave now are going to be determining the temperatures of our cities in the next century”

In those patches where two or more trees met and two-fifths of the sky was screened by foliage, the temperature dropped by an average of 3.5°C and sometimes − especially where the number of trees and their proximity delivered ever more shade − by up to 5.7°C.

Trees not only deliver shade, they transpire. That is, they exhale water through the stomata in their leaves and provide a second outdoor air-conditioning mechanism. The difference, too, between shade and sunlight temperatures can set up an air flow.

The results, reported in the Proceedings of the National Academy of Sciences, “suggest strategies for managing urban land-cover patterns to enhance resilience to cities’ warming.” In other words, trees are good things to plant, anywhere, but especially in the concrete jungle.

Once again, this is no surprise. Researchers have been looking at what might be called the green response to urban warming for years, and found that urban tree cover can add as much as $500m to the economies of the great cities.

Urban trees don’t just deliver shade, they can soak up atmospheric carbon in ways that match any rainforest giant, and the simple presence of trees in suburban roads can add appreciably to property values as well as simple amenity.

Hotter cities

And tomorrow’s cities will need help from the trees. More than half of the world’s population is already crammed into cities, and all cities are plagued by what is known as the urban heat island effect: that is, because of lighting, central heating, air conditioning, traffic, tarmac, tiles and slate, metro systems, and light industry, cities can be hotter than the surrounding countryside by 3°C or more.

With global warming so far on track to reach a global average of 3°C higher than at any time in human history by the century’s end – when cities will be even more crowded as population soars – city planners need a low-cost answer to what promises to be the serious and potentially lethal health hazard of ever more intense and prolonged heatwaves.

And not only do trees deliver cool shade: there is even research to suggest that they do better in the warmer cities. The Madison studies offer fine detail to something most city dwellers know intuitively. Cities need green spaces and tree-lined avenues. The next step is to work out how best to use such findings.

“It’s not really enough to just kind of go out and plant trees, we really need to think about how many we are planting and where we’re planting them. We’re not saying planting one tree does nothing, but you’re going to have a bigger effect if you plant a tree and your neighbour plants a tree and their neighbour plants a tree,” Dr Ziter said.

“The trees we plant now or the areas we pave now are going to be determining the temperatures of our cities in the next century.” − Climate News Network

Ice melt makes Arctic soils slip more often

As warm summers loosen the grip of the polar ice, the Arctic soils begin to shift. And they are now shifting faster than ever before.

LONDON, 9 April, 2019 − Global warming is about to change the face of the frozen polar landmass, where the Arctic soils are slipping and sliding at record speed. Once-firm ground has begun to shift.

Researchers who closely examined landslips and slumps on Banks Island in the Canadian Arctic Archipelago have found a sixty-fold increase in ground movement in the last 30 years.

In 1984, summer temperatures accounted for just 60 events of the kind glaciologists know as retrogressive thaw slumps or collapses of surface soil as the permafrost ice begins to melt. In 2014, there were more than 4,000 such slumps, including about 300 in an area protected as a natural park.

And on Banks Island alone, even under a relatively conservative scenario, this number could grow to 10,000 a decade by 2075, to precipitate as many as 30,000 active landslides in any future year.

“We can encourage our politicians to take the necessary measures to help reduce our greenhouse emissions, so that future warming is as limited as possible”

Researchers report in the journal Nature Communications that massive amounts of sediment released by the slumps have choked river valleys and changed the colour of 288 lakes. Once a thaw slump begins, soils once held stable by the frost can go on sliding or slipping.

Nobody can be sure of the impact on the natural ecosystems, but the island is home to arctic foxes, caribou, polar bears, wolves, musk oxen, arctic hare, lemmings, ermine, seal and even grizzly bears.

It also provides feeding grounds for lesser snow geese, black brants, eiders, peregrine falcons, snowy owls, rough-legged hawks and ravens.

And, the scientists say, a small local Inuit population based on the island can confirm the ground truth of satellite records: ground slumps increasingly make it difficult to go hunting or fishing.

Methane risk

The study is hardly the first to suggest that global warming will change the high Arctic, but it may be the first to put firm estimates to the increasing scale of damage through time. The implication is that what happens on Banks Island could also happen at the same latitudes anywhere.

Climate scientists have been increasingly alarmed at the hazards of permafrost thaw, if only because locked in the frozen soils are millennia of plant remains, all of which could decay into methane and accelerate global warming to melt yet more permafrost and drive global average temperatures ever higher.

Geographers have already warned that what had once been hard ground beneath roads, buildings, factories, airfields and housing has already begun to slump, to devastate infrastructure and even threaten oil and gas piping.

“We cannot stop thousands of thaw slumps once they start,” said Antoni Lewkowicz of the University of Ottawa, who led the research. “We can only make changes in our own lives to reduce our carbon footprint and we can encourage our politicians to take the necessary measures to help reduce our greenhouse emissions, so that future warming is as limited as possible.” − Climate News Network

As warm summers loosen the grip of the polar ice, the Arctic soils begin to shift. And they are now shifting faster than ever before.

LONDON, 9 April, 2019 − Global warming is about to change the face of the frozen polar landmass, where the Arctic soils are slipping and sliding at record speed. Once-firm ground has begun to shift.

Researchers who closely examined landslips and slumps on Banks Island in the Canadian Arctic Archipelago have found a sixty-fold increase in ground movement in the last 30 years.

In 1984, summer temperatures accounted for just 60 events of the kind glaciologists know as retrogressive thaw slumps or collapses of surface soil as the permafrost ice begins to melt. In 2014, there were more than 4,000 such slumps, including about 300 in an area protected as a natural park.

And on Banks Island alone, even under a relatively conservative scenario, this number could grow to 10,000 a decade by 2075, to precipitate as many as 30,000 active landslides in any future year.

“We can encourage our politicians to take the necessary measures to help reduce our greenhouse emissions, so that future warming is as limited as possible”

Researchers report in the journal Nature Communications that massive amounts of sediment released by the slumps have choked river valleys and changed the colour of 288 lakes. Once a thaw slump begins, soils once held stable by the frost can go on sliding or slipping.

Nobody can be sure of the impact on the natural ecosystems, but the island is home to arctic foxes, caribou, polar bears, wolves, musk oxen, arctic hare, lemmings, ermine, seal and even grizzly bears.

It also provides feeding grounds for lesser snow geese, black brants, eiders, peregrine falcons, snowy owls, rough-legged hawks and ravens.

And, the scientists say, a small local Inuit population based on the island can confirm the ground truth of satellite records: ground slumps increasingly make it difficult to go hunting or fishing.

Methane risk

The study is hardly the first to suggest that global warming will change the high Arctic, but it may be the first to put firm estimates to the increasing scale of damage through time. The implication is that what happens on Banks Island could also happen at the same latitudes anywhere.

Climate scientists have been increasingly alarmed at the hazards of permafrost thaw, if only because locked in the frozen soils are millennia of plant remains, all of which could decay into methane and accelerate global warming to melt yet more permafrost and drive global average temperatures ever higher.

Geographers have already warned that what had once been hard ground beneath roads, buildings, factories, airfields and housing has already begun to slump, to devastate infrastructure and even threaten oil and gas piping.

“We cannot stop thousands of thaw slumps once they start,” said Antoni Lewkowicz of the University of Ottawa, who led the research. “We can only make changes in our own lives to reduce our carbon footprint and we can encourage our politicians to take the necessary measures to help reduce our greenhouse emissions, so that future warming is as limited as possible.” − Climate News Network

CO2 levels pass 3-million-year record

The modern world is about to pass a temperature peak dating back for millions of years – because CO2 levels have already passed an ancient record..

LONDON, 8 April, 2019 – German scientists have confirmed, once again, that carbon dioxide is reaching concentrations unprecedented on any human time scale, with CO2 levels in the atmosphere already higher than they have been for at least three million years.

And their computer simulations – backed up by analysis of ocean sediments that tell a tale of changing temperatures and greenhouse gas levels – show that before the century’s close the world will become warmer than at any time in the last three million years.

The last time planetary temperatures reached a level higher than the target set by 195 nations in Paris in 2015 was during a bygone geological period, the Pliocene.

“It seems we are now pushing our home planet beyond any climatic conditions experienced during the entire current geological period, the Quaternary,” said Matteo Willeit of the Potsdam Institute for Climate Impact Research.

“Our results imply a strong sensitivity of the Earth system to relatively small changes in atmospheric CO2. As fascinating as this is, it is also worrying”

“A period that started almost three million years ago and saw human civilisation beginning only 11,000 years ago. So the modern change we see is big, really big, even by the standards of Earth history.”

He and colleagues report in the journal Science Advances  that they made a numerical model of all the astronomical and geological data available for the last few million years and fed in algorithms to represent the physics and chemistry of planet Earth.

So they had a simulation of a rocky planet complete with active volcanoes that emit carbon dioxide with their magma, on a journey many times around a slowly-changing elliptical orbit that subtly changed the levels of sunshine that slammed into the rocks, oceans and forests – patterns of change called the Milankovitch cycles, long implicated in periodic shifts in planetary climate.

They also fed in data about sediments in the high latitudes: important because ice sheets advance more easily over gravel than bedrock, and atmospheric dust from such attrition makes ice surfaces darker and more vulnerable to melting. The result: confirmation of one thing already observed and another much feared.

Carbon ratio leaps

At a time in the astronomical cycle when Earthlings might expect a slow return of the Ice Ages, human action over the last two centuries – the profligate combustion of fossil fuels that emit greenhouse gases, the wholesale clearance of the great forests that absorb atmospheric carbon – has already lifted carbon dioxide ratios from a long-term average of around 280 parts per million to more than 400 ppm.

Human action has also raised long-term average planetary temperatures by a whole degree Celsius, with more warming on the way.

A new Ice Age seems increasingly unlikely, and other researchers have already pointed to the Pliocene data as a soon-to-be-exceeded record.

Entirely different studies have shown the world to be on course to exceed the 2°C limit, so the research confirms other findings and delivers a test of the reliability of evidence from the past. It also backs up the value of simulation as an increasingly reliable form of climate forecasting.

CO2’s key role

“We know from the analysis of sediments on the bottom of our seas about past ocean temperatures and ice volumes, but so far the role of CO2 in shaping the glacial cycles has not been fully understood,” said Dr Willeit.

“It is a breakthrough that we can now show in computer simulations that changes in CO2 levels were a main driver of the Ice Ages, together with variations of how the Earth orbits around the sun, the so-called Milankovitch cycles. These are actually not just simulations: we compared our results with hard data from the deep sea, and they prove to be in good agreement,” he said.

“Our results imply a strong sensitivity of the Earth system to relatively small changes in atmospheric CO2. As fascinating as this is, it is also worrying.” – Climate News Network

The modern world is about to pass a temperature peak dating back for millions of years – because CO2 levels have already passed an ancient record..

LONDON, 8 April, 2019 – German scientists have confirmed, once again, that carbon dioxide is reaching concentrations unprecedented on any human time scale, with CO2 levels in the atmosphere already higher than they have been for at least three million years.

And their computer simulations – backed up by analysis of ocean sediments that tell a tale of changing temperatures and greenhouse gas levels – show that before the century’s close the world will become warmer than at any time in the last three million years.

The last time planetary temperatures reached a level higher than the target set by 195 nations in Paris in 2015 was during a bygone geological period, the Pliocene.

“It seems we are now pushing our home planet beyond any climatic conditions experienced during the entire current geological period, the Quaternary,” said Matteo Willeit of the Potsdam Institute for Climate Impact Research.

“Our results imply a strong sensitivity of the Earth system to relatively small changes in atmospheric CO2. As fascinating as this is, it is also worrying”

“A period that started almost three million years ago and saw human civilisation beginning only 11,000 years ago. So the modern change we see is big, really big, even by the standards of Earth history.”

He and colleagues report in the journal Science Advances  that they made a numerical model of all the astronomical and geological data available for the last few million years and fed in algorithms to represent the physics and chemistry of planet Earth.

So they had a simulation of a rocky planet complete with active volcanoes that emit carbon dioxide with their magma, on a journey many times around a slowly-changing elliptical orbit that subtly changed the levels of sunshine that slammed into the rocks, oceans and forests – patterns of change called the Milankovitch cycles, long implicated in periodic shifts in planetary climate.

They also fed in data about sediments in the high latitudes: important because ice sheets advance more easily over gravel than bedrock, and atmospheric dust from such attrition makes ice surfaces darker and more vulnerable to melting. The result: confirmation of one thing already observed and another much feared.

Carbon ratio leaps

At a time in the astronomical cycle when Earthlings might expect a slow return of the Ice Ages, human action over the last two centuries – the profligate combustion of fossil fuels that emit greenhouse gases, the wholesale clearance of the great forests that absorb atmospheric carbon – has already lifted carbon dioxide ratios from a long-term average of around 280 parts per million to more than 400 ppm.

Human action has also raised long-term average planetary temperatures by a whole degree Celsius, with more warming on the way.

A new Ice Age seems increasingly unlikely, and other researchers have already pointed to the Pliocene data as a soon-to-be-exceeded record.

Entirely different studies have shown the world to be on course to exceed the 2°C limit, so the research confirms other findings and delivers a test of the reliability of evidence from the past. It also backs up the value of simulation as an increasingly reliable form of climate forecasting.

CO2’s key role

“We know from the analysis of sediments on the bottom of our seas about past ocean temperatures and ice volumes, but so far the role of CO2 in shaping the glacial cycles has not been fully understood,” said Dr Willeit.

“It is a breakthrough that we can now show in computer simulations that changes in CO2 levels were a main driver of the Ice Ages, together with variations of how the Earth orbits around the sun, the so-called Milankovitch cycles. These are actually not just simulations: we compared our results with hard data from the deep sea, and they prove to be in good agreement,” he said.

“Our results imply a strong sensitivity of the Earth system to relatively small changes in atmospheric CO2. As fascinating as this is, it is also worrying.” – Climate News Network