Tag Archives: Forests

Savage heat engulfs temperate Tasmania

One Australian state hit severely this ferocious summer is normally temperate Tasmania. A resident with vivid experience describes its ordeal.

TASMANIA, 14 February, 2019 − Australia has been going through one of its hottest and stormiest summers on record and usually temperate Tasmania, its island state, has taken a battering..

Climate change-related weather events have brought cyclones and raging floods to the north-east of the country, while drought and temperatures exceeding 40°C have resulted in parched lands and rivers drying up in areas of New South Wales.

Summer on the island of Tasmania, Australia’s most southerly state, with a generally temperate climate, is usually a time for BBQs and beach swimming. This summer has been very different.

A prolonged drought and record high temperatures have caused a series of devastating fires, destroying unique forests and vegetation and forcing people to leave their homes.

Critics of the Australian government say it’s clear climate change is wreaking havoc; meanwhile politicians continue to pander to the interests of the country’s powerful mining and fossil fuel industries.

“It’s a giant, macabre game of cat and mouse”

Mike Willson is a Tasmania resident, a fire equipment specialist and a volunteer with the Tasmania Fire Service. Here he tells Climate News Network what life has been like on the island over recent weeks.

“There is menace in the air. Days full of thick brown smoke. The clouds of smoke have even been swept across 2,500 kilometres of ocean to as far away as New Zealand – itself trying to cope with its own forest fires.

“A new phenomenon has arrived in Tasmania – lightning storms without rain. In one day in mid-January there were over 2,000 dry lightning strikes over the south-west and central highlands here, starting up to 70 bush fires.

““ Even with water bombing by planes and helicopters, the fires – which have already burned out 3% of the area of the island – are virtually impossible to control.

Leaping ahead

“Dealing with these fires is like fighting a snarling dragon. Small flakes of grey ash fall everywhere. Embers can trigger spot fires several kilometres ahead of the main fire.

“The fire can seem to disappear but still burns in logs and stumps. You have to always be on the lookout for tell-tale wisps of smoke. Walking across with a hose line to investigate, it’s a moonscape, the soil collapsing under your feet.

““ It’s like trudging through powder snow, sinking up to mid-calf in places, with the earth under your feet turning to hot dust. Aiming at a puff of smoke, the ground erupts and hisses like a volcano when we spray water.

“It’s a giant, macabre game of cat and mouse. If conditions are right, a controlled back burn can effectively starve the fire of fuel, but then the wind might whip up and the fire can jump – even across large rivers and bays – and rampage on.

Disaster avoided

“Luckily, so far there have been no casualties, and few homes have been lost. At least the drought and high temperatures have not come with very high winds – a cocktail for disaster.

“Firefighter and helicopter crews are being constantly rotated – it all takes a considerable physical and mental toll.”

*

In recent days rainfall over much of Tasmania has eased the fire risk, though the authorities are warning people that there is still a danger of further fire outbreaks.

Among the areas threatened or partially destroyed by fire are the world’s largest remaining forest of thousand-year-old King Billy pines. − Climate News Network

One Australian state hit severely this ferocious summer is normally temperate Tasmania. A resident with vivid experience describes its ordeal.

TASMANIA, 14 February, 2019 − Australia has been going through one of its hottest and stormiest summers on record and usually temperate Tasmania, its island state, has taken a battering..

Climate change-related weather events have brought cyclones and raging floods to the north-east of the country, while drought and temperatures exceeding 40°C have resulted in parched lands and rivers drying up in areas of New South Wales.

Summer on the island of Tasmania, Australia’s most southerly state, with a generally temperate climate, is usually a time for BBQs and beach swimming. This summer has been very different.

A prolonged drought and record high temperatures have caused a series of devastating fires, destroying unique forests and vegetation and forcing people to leave their homes.

Critics of the Australian government say it’s clear climate change is wreaking havoc; meanwhile politicians continue to pander to the interests of the country’s powerful mining and fossil fuel industries.

“It’s a giant, macabre game of cat and mouse”

Mike Willson is a Tasmania resident, a fire equipment specialist and a volunteer with the Tasmania Fire Service. Here he tells Climate News Network what life has been like on the island over recent weeks.

“There is menace in the air. Days full of thick brown smoke. The clouds of smoke have even been swept across 2,500 kilometres of ocean to as far away as New Zealand – itself trying to cope with its own forest fires.

“A new phenomenon has arrived in Tasmania – lightning storms without rain. In one day in mid-January there were over 2,000 dry lightning strikes over the south-west and central highlands here, starting up to 70 bush fires.

““ Even with water bombing by planes and helicopters, the fires – which have already burned out 3% of the area of the island – are virtually impossible to control.

Leaping ahead

“Dealing with these fires is like fighting a snarling dragon. Small flakes of grey ash fall everywhere. Embers can trigger spot fires several kilometres ahead of the main fire.

“The fire can seem to disappear but still burns in logs and stumps. You have to always be on the lookout for tell-tale wisps of smoke. Walking across with a hose line to investigate, it’s a moonscape, the soil collapsing under your feet.

““ It’s like trudging through powder snow, sinking up to mid-calf in places, with the earth under your feet turning to hot dust. Aiming at a puff of smoke, the ground erupts and hisses like a volcano when we spray water.

“It’s a giant, macabre game of cat and mouse. If conditions are right, a controlled back burn can effectively starve the fire of fuel, but then the wind might whip up and the fire can jump – even across large rivers and bays – and rampage on.

Disaster avoided

“Luckily, so far there have been no casualties, and few homes have been lost. At least the drought and high temperatures have not come with very high winds – a cocktail for disaster.

“Firefighter and helicopter crews are being constantly rotated – it all takes a considerable physical and mental toll.”

*

In recent days rainfall over much of Tasmania has eased the fire risk, though the authorities are warning people that there is still a danger of further fire outbreaks.

Among the areas threatened or partially destroyed by fire are the world’s largest remaining forest of thousand-year-old King Billy pines. − Climate News Network

Energy from greenhouse gases is possible

Laboratories can make energy from greenhouse gases, power smartphones with their own radiation, and cut shipping costs naturally. And each could become reality.

LONDON, 8 February, 2019 – Researchers have found ways to realise a modern version of the medieval alchemists’ dream  not turning base metals into gold, but conjuring energy from greenhouse gases, exploiting abundant pollutants to help to power the world.

Korean scientists have developed a sophisticated fuel cell that consumes carbon dioxide and produces electricity and hydrogen – potentially another fuel – at the same time.

Researchers based in the US and Spain have devised a nanoscale fabric that converts electromagnetic waves into electrical current.

The dream is that a smartphone coated with the fabric could, without benefit of a battery, charge itself from the ambient wi-fi radiation that it exploits for texts, calls and data.

German scientists have taken a leaf from nature’s book and applied it – so far in theory – to bulk cargo shipping. Salvinia molesta, a floating fern native to Brazil, isolates itself from water with a thin sheath of air. If the large carriers could adopt the Salvinia trick and incorporate a similar layer of air in the anti-fouling coating on the hull, this would reduce drag sufficiently to save 20% of fuel costs.

To the Urals

And in yet another demonstration of the ingenuity and innovative ambition on show in the world’s laboratories, another German team has looked at the large-scale climate economics of artificial photosynthesis – a system of semiconductors and oxides – that could draw down carbon dioxide from the atmosphere and deliver stable chemical compounds.

To take 10 billion metric tons of carbon dioxide out of the atmosphere each year would demand a forest that covered all Europe as far as the Urals. But to do the same job, a commercial forest of “artificial leaves” would require a land area about the size of the German federal state of Brandenburg.

All these ideas are ready for further development. None is so far anywhere near the commercial market.

But all are evidence that chemists, engineers, physicists and biologists have taken up the great climate challenge: how to power modern society without fuelling even faster global warming and climate change that could, ultimately, bring global economic growth to a devastating halt.

And, as many researchers see it, that means not just by-passing the fossil fuels that drive climate change, but actively exploiting the ever-higher ratios of carbon dioxide now in the atmosphere, or soon to emerge from power station chimneys

“The best thing now would be to drastically reduce emissions immediately – that would be safer and much cheaper”

Scientists at UNIST, Korea’s National Institute of Science and Technology, report in the journal iScience that in collaboration with engineers at the Georgia Institute of Technology in the US they have already developed a hybrid sodium-carbon dioxide system of electrolytes that converts dissolved carbon dioxide to sodium bicarbonate and hydrogen, with a flow of electric current.

Efficiency is high – with 50% of the carbon dioxide exploited – and could be higher. And their test apparatus so far has run in stable fashion for 1000 hours. The system uses a new approach to materials to exploit something in the air everywhere.

And that too is exactly what researchers in the US have done: they report in the journal Nature that they have fashioned a flexible sheet of ultra-thin material that serves as what they call a “rectenna”: a radio-frequency antenna that harvests radiation, including wi-fi signals, as alternating current waveforms, and feeds them to a nanoscale semiconductor that converts it to direct current.

So far, the rectenna devices have produced 40 microwatts of power: enough to fire up a light-emitting diode, or power a silicon chip.

“We have come up with a new way to power the electronics systems of the future – by harvesting wi-fi energy in a way that’s easily integrated in large areas – to bring intelligence to every object around us,” said Tomás Palacios, an electrical engineer at Massachusetts Institute of Technology, and one of the authors.

Magic carpet

The waterweed Salvinia molesta exploits bubbles to keep itself afloat but out of the water: it literally rides in the water on a little magic carpet of air. The hydrophobic plant is regarded as an invasive pest, but the way it harnesses air to keep itself afloat and on top of things provides a lesson not just for evolutionary biologists but for engineers.

Researchers from the University of Bonn have been looking at the problem of the global shipping fleet: cargo freighters burn 250 million tonnes of fuel a year and emit a billion tonnes of carbon dioxide, much of it because of the sheer drag of moving a hull through the waves. So anything that reduces drag saves fuel (which accounts for half of all transport costs).

The German scientists report in the Philosophical Transactions A of the Royal Society that their experiments with hull coatings based on the lessons of Salvinia could in the medium term cut fuel costs by up to 20% and on a global scale reduce emissions by 130 million tonnes a year. If the same coating discouraged barnacles as well, the saving could reach 300 million tonnes – 1% of global CO2 output.

To keep global warming to the promised level of no more than 1.5°C, an ambition signed up to by 195 nations in Paris in 2015, global fossil fuel emissions will have to reach zero by 2050.

Right now, nations are adding 42 billion tonnes of carbon dioxide to the atmosphere every year. So there is pressure to find ways to remove carbon from the atmosphere and store it.

Huge economy

German scientists report in the journal Earth System Dynamics that they did the sums and calculated that to take 10 billion tonnes of carbon dioxide out of the atmosphere using the machinery supplied by 3 billion years of evolution would require new forest plantations that stretched over 10 million kilometres. This is about the size of continental Europe.

But supposing artificial leaf systems developed in laboratories could be further developed on a massive scale? These leaves would draw down carbon dioxide and deliver it for permanent storage or for chemical conversion to plastic or building material.

If so, then efficient synthetic photosynthesis installations could do the same job from an area of only 30,000 square kilometres.

“These kinds of modules could be placed in non-agricultural regions – in deserts, for example. In contrast to plants, they require hardly any water to operate,” said Matthias May of the Helmholtz-Zentrum Berlin, one of the authors. It would of course come at a formidable cost – about €650 bn
or US$740 bn a year.

“The best thing now,” Dr May said, “would be to drastically reduce emissions immediately – that would be safer and much cheaper.” – Climate News Network

Laboratories can make energy from greenhouse gases, power smartphones with their own radiation, and cut shipping costs naturally. And each could become reality.

LONDON, 8 February, 2019 – Researchers have found ways to realise a modern version of the medieval alchemists’ dream  not turning base metals into gold, but conjuring energy from greenhouse gases, exploiting abundant pollutants to help to power the world.

Korean scientists have developed a sophisticated fuel cell that consumes carbon dioxide and produces electricity and hydrogen – potentially another fuel – at the same time.

Researchers based in the US and Spain have devised a nanoscale fabric that converts electromagnetic waves into electrical current.

The dream is that a smartphone coated with the fabric could, without benefit of a battery, charge itself from the ambient wi-fi radiation that it exploits for texts, calls and data.

German scientists have taken a leaf from nature’s book and applied it – so far in theory – to bulk cargo shipping. Salvinia molesta, a floating fern native to Brazil, isolates itself from water with a thin sheath of air. If the large carriers could adopt the Salvinia trick and incorporate a similar layer of air in the anti-fouling coating on the hull, this would reduce drag sufficiently to save 20% of fuel costs.

To the Urals

And in yet another demonstration of the ingenuity and innovative ambition on show in the world’s laboratories, another German team has looked at the large-scale climate economics of artificial photosynthesis – a system of semiconductors and oxides – that could draw down carbon dioxide from the atmosphere and deliver stable chemical compounds.

To take 10 billion metric tons of carbon dioxide out of the atmosphere each year would demand a forest that covered all Europe as far as the Urals. But to do the same job, a commercial forest of “artificial leaves” would require a land area about the size of the German federal state of Brandenburg.

All these ideas are ready for further development. None is so far anywhere near the commercial market.

But all are evidence that chemists, engineers, physicists and biologists have taken up the great climate challenge: how to power modern society without fuelling even faster global warming and climate change that could, ultimately, bring global economic growth to a devastating halt.

And, as many researchers see it, that means not just by-passing the fossil fuels that drive climate change, but actively exploiting the ever-higher ratios of carbon dioxide now in the atmosphere, or soon to emerge from power station chimneys

“The best thing now would be to drastically reduce emissions immediately – that would be safer and much cheaper”

Scientists at UNIST, Korea’s National Institute of Science and Technology, report in the journal iScience that in collaboration with engineers at the Georgia Institute of Technology in the US they have already developed a hybrid sodium-carbon dioxide system of electrolytes that converts dissolved carbon dioxide to sodium bicarbonate and hydrogen, with a flow of electric current.

Efficiency is high – with 50% of the carbon dioxide exploited – and could be higher. And their test apparatus so far has run in stable fashion for 1000 hours. The system uses a new approach to materials to exploit something in the air everywhere.

And that too is exactly what researchers in the US have done: they report in the journal Nature that they have fashioned a flexible sheet of ultra-thin material that serves as what they call a “rectenna”: a radio-frequency antenna that harvests radiation, including wi-fi signals, as alternating current waveforms, and feeds them to a nanoscale semiconductor that converts it to direct current.

So far, the rectenna devices have produced 40 microwatts of power: enough to fire up a light-emitting diode, or power a silicon chip.

“We have come up with a new way to power the electronics systems of the future – by harvesting wi-fi energy in a way that’s easily integrated in large areas – to bring intelligence to every object around us,” said Tomás Palacios, an electrical engineer at Massachusetts Institute of Technology, and one of the authors.

Magic carpet

The waterweed Salvinia molesta exploits bubbles to keep itself afloat but out of the water: it literally rides in the water on a little magic carpet of air. The hydrophobic plant is regarded as an invasive pest, but the way it harnesses air to keep itself afloat and on top of things provides a lesson not just for evolutionary biologists but for engineers.

Researchers from the University of Bonn have been looking at the problem of the global shipping fleet: cargo freighters burn 250 million tonnes of fuel a year and emit a billion tonnes of carbon dioxide, much of it because of the sheer drag of moving a hull through the waves. So anything that reduces drag saves fuel (which accounts for half of all transport costs).

The German scientists report in the Philosophical Transactions A of the Royal Society that their experiments with hull coatings based on the lessons of Salvinia could in the medium term cut fuel costs by up to 20% and on a global scale reduce emissions by 130 million tonnes a year. If the same coating discouraged barnacles as well, the saving could reach 300 million tonnes – 1% of global CO2 output.

To keep global warming to the promised level of no more than 1.5°C, an ambition signed up to by 195 nations in Paris in 2015, global fossil fuel emissions will have to reach zero by 2050.

Right now, nations are adding 42 billion tonnes of carbon dioxide to the atmosphere every year. So there is pressure to find ways to remove carbon from the atmosphere and store it.

Huge economy

German scientists report in the journal Earth System Dynamics that they did the sums and calculated that to take 10 billion tonnes of carbon dioxide out of the atmosphere using the machinery supplied by 3 billion years of evolution would require new forest plantations that stretched over 10 million kilometres. This is about the size of continental Europe.

But supposing artificial leaf systems developed in laboratories could be further developed on a massive scale? These leaves would draw down carbon dioxide and deliver it for permanent storage or for chemical conversion to plastic or building material.

If so, then efficient synthetic photosynthesis installations could do the same job from an area of only 30,000 square kilometres.

“These kinds of modules could be placed in non-agricultural regions – in deserts, for example. In contrast to plants, they require hardly any water to operate,” said Matthias May of the Helmholtz-Zentrum Berlin, one of the authors. It would of course come at a formidable cost – about €650 bn
or US$740 bn a year.

“The best thing now,” Dr May said, “would be to drastically reduce emissions immediately – that would be safer and much cheaper.” – Climate News Network

Coffee harvests face risk from rising heat

Global coffee harvests, which provide the drink of choice for millions and the livelihoods of many more, are in peril, not least from rising temperatures.

LONDON, 28 January, 2019 – Coffee drinkers, be warned. A combination of factors – including climate change – is threatening supplies of the beans on which the coffee harvests depend.

Latest analysis by a team of scientists at the Royal Botanic Gardens at Kew in London found that more than 60% of over 120 coffee species known across Africa, Asia and Australasia are threatened with extinction.

For many people, coffee is their favourite tipple. In the UK alone, more than 80 million cups of coffee are drunk every day. The experts at Kew say a total of 100 million people around the world depend on coffee for their livelihoods.

Climate change, together with fungal diseases and the impact of land clearances and deforestation, are all having negative impacts on coffee plants.

Coffee plants are fragile and often acutely sensitive to temperature changes, particularly those belonging to the Arabica species (Coffea arabica), the source of the world’s most popular coffee variety.

“Climate change will have a damaging impact on commercial coffee production worldwide”

The Coffee Research Institute says Arabica plants need year-round temperatures of between 15°C and 24°C in order to maintain high production levels and good quality.

Wild coffee plants play an essential role in building up more robust plants for cultivation; cross-bred with plantation plants, they provide the genetic resources to help withstand pests and diseases. They also encourage resilience to changes in climate and improve the flavour and quality of the coffee beans.

The Kew scientists, together with colleagues in Ethiopia,
the biggest producer of Arabica coffee in Africa, used climate change models and temperature projections to gauge the future health and survival rates of wild Arabica plants.

The results of the analysis, the first ever comprehensive survey linking climate change with Arabica coffee production, will have coffee drinkers crying into their cups.

Wide extinction threat

Dr Justin Moat, who headed up the Kew study, says more than 60% of wild Arabica plants are threatened with extinction.

“The worst case scenario, as drawn from our analyses, is that wild Arabica could be extinct by 2080.

“This should alert decision makers to the fragility of the species.”

The highlands of Ethiopia and of South Sudan are the natural home of Arabica coffee. Researchers found that deforestation over the past 70 years plus more recent changes in climate could result in wild Arabica becoming extinct in South Sudan within the next two years.

“The climate sensitivity of Arabica is confirmed, supporting the widely reported assumption that climate change will have a damaging impact on commercial coffee production worldwide”, says Dr Moat.

Pay growers more

In coffee-growing areas around the world, including Ethiopia and Brazil, temperatures have been rising while amounts of rainfall have been decreasing.

The Kew study says that while bumper coffee harvests over the last two years have led to generally low prices, this pattern is unlikely to continue as crop yields decline and demand grows.

The study says coffee growers, mostly smallholders, should be paid more for their produce in order not only to improve living standards but to encourage more sustainable and innovative cultivation methods. The Yayu Project in Ethiopia is seen as a model for this form of development.

There should also be more research into wild coffee species and investment in building up collections and seed banks. – Climate News Network

Global coffee harvests, which provide the drink of choice for millions and the livelihoods of many more, are in peril, not least from rising temperatures.

LONDON, 28 January, 2019 – Coffee drinkers, be warned. A combination of factors – including climate change – is threatening supplies of the beans on which the coffee harvests depend.

Latest analysis by a team of scientists at the Royal Botanic Gardens at Kew in London found that more than 60% of over 120 coffee species known across Africa, Asia and Australasia are threatened with extinction.

For many people, coffee is their favourite tipple. In the UK alone, more than 80 million cups of coffee are drunk every day. The experts at Kew say a total of 100 million people around the world depend on coffee for their livelihoods.

Climate change, together with fungal diseases and the impact of land clearances and deforestation, are all having negative impacts on coffee plants.

Coffee plants are fragile and often acutely sensitive to temperature changes, particularly those belonging to the Arabica species (Coffea arabica), the source of the world’s most popular coffee variety.

“Climate change will have a damaging impact on commercial coffee production worldwide”

The Coffee Research Institute says Arabica plants need year-round temperatures of between 15°C and 24°C in order to maintain high production levels and good quality.

Wild coffee plants play an essential role in building up more robust plants for cultivation; cross-bred with plantation plants, they provide the genetic resources to help withstand pests and diseases. They also encourage resilience to changes in climate and improve the flavour and quality of the coffee beans.

The Kew scientists, together with colleagues in Ethiopia,
the biggest producer of Arabica coffee in Africa, used climate change models and temperature projections to gauge the future health and survival rates of wild Arabica plants.

The results of the analysis, the first ever comprehensive survey linking climate change with Arabica coffee production, will have coffee drinkers crying into their cups.

Wide extinction threat

Dr Justin Moat, who headed up the Kew study, says more than 60% of wild Arabica plants are threatened with extinction.

“The worst case scenario, as drawn from our analyses, is that wild Arabica could be extinct by 2080.

“This should alert decision makers to the fragility of the species.”

The highlands of Ethiopia and of South Sudan are the natural home of Arabica coffee. Researchers found that deforestation over the past 70 years plus more recent changes in climate could result in wild Arabica becoming extinct in South Sudan within the next two years.

“The climate sensitivity of Arabica is confirmed, supporting the widely reported assumption that climate change will have a damaging impact on commercial coffee production worldwide”, says Dr Moat.

Pay growers more

In coffee-growing areas around the world, including Ethiopia and Brazil, temperatures have been rising while amounts of rainfall have been decreasing.

The Kew study says that while bumper coffee harvests over the last two years have led to generally low prices, this pattern is unlikely to continue as crop yields decline and demand grows.

The study says coffee growers, mostly smallholders, should be paid more for their produce in order not only to improve living standards but to encourage more sustainable and innovative cultivation methods. The Yayu Project in Ethiopia is seen as a model for this form of development.

There should also be more research into wild coffee species and investment in building up collections and seed banks. – Climate News Network

Satellites can be sustainable monitors

Remote sensing by satellites and sound recorders could yield answers to complex global questions and reveal what is happening in the world’s great forests.

LONDON, 9 January, 2019 − High tech answers using satellites and sound recorders could contribute to solving the global information crisis. To check on progress towards world development and conservation goals, researchers could exploit the highest technology of all.

Satellite data and number-crunching computer analysis could identify the world’s poorest households, and those on the way to new hope. And subtle listening devices planted in primal rainforest and near human settlements could provide a low-cost, high-speed check on biodiversity loss and conservation efforts in the developing world.

In effect, researchers argue in two entirely separate studies, the look-and-listen approach could deliver effective levels of information at relatively low expense, and keep nations and international monitoring organisations informed on issues ultimately inseparable from climate change driven by human appropriation of the planet’s resources.

At the heart of each is the search for a sustainable way of monitoring sustainable development. The governments of 93 nations have committed themselves to the UN’s sustainable development goals, to help lift their citizens out of poverty while maintaining the natural resources on which they must rely.

“When we use space data with a socio-ecological insight, we capture the financial status and, in this way, also the development in an area much better”

Danish, British and US researchers report in the Proceedings of the National Academy of Sciences that if social scientists were to rely on traditional methods of research − house-to-house surveys and questionnaires of sample populations on an annual basis and so on − the cost could add up, over the lifetime of the programme, to $253 billion. This is almost twice what the world spent on global development assistance in 2013.

But satellite studies, already massed for other purposes, could hold most of the answers in fine detail already. “Based on high resolution satellite images, we can very precisely assess the poverty at household level in rural areas in developing countries,” said Jens-Christian Svenning, a bioscientist at Aarhus University in Denmark.

“The method that we have developed is designed to analyse the satellite images in a way that takes into account that people have access to and use different resources in the landscape at different levels,” he said.

“Some use the area just around their house, while others use the common areas of a village. When we use space data with a socio-ecological insight, we capture the financial status and, in this way, also the development in an area much better than we have previously been able to.”

Better prospects

There are 17 declared sustainable development goals that could, by 2030, make the world a better place for the people of the poorest countries, without loss of the wildlife around them and without adding to the profligate use of fossil fuels to deliver the energy to fuel potentially catastrophic global warming along with economic growth.

The Aarhus team has already tested their approach in rural western Kenya, to confirm that satellite data could account for 62% of the variation in household wealth: the size of buildings within one homestead, the amount of bare ground within it and the size of the agricultural land around it − and the length of the growing season − were enough to answer important questions.

And since the body of data available from satellite observation is continuously growing, this would offer a substitute for on-the-ground annual monitoring visits, which, they say, would be “prohibitively expensive.”

Within the same week, US and Australian scientists argue in the journal Science for a simple, bio-acoustics approach to ways of measuring and monitoring conservation efforts in the world’s tropical forests.

Listening in

These could yield treasuries of information. Important ecological data could be recovered from what they call “soundscapes” of animal and human activity in the vast tracts of forest that provide a home for most of the world’s terrestrial species, while at the same time drawing down carbon dioxide from the atmosphere and turning it into timber to slow the seemingly-inexorable rise in greenhouse gas concentrations that has already lifted global average temperatures by 1°C, reachimg perhaps a devastating 3°C increase by the end of the century.

Satellite images can answer questions about the loss of forests on a wide scale. But these cannot easily identify other problems, among them overhunting, fires or invasion by exotic species. And field surveys are costly, time-consuming and possible only over small samples of forest. But sound-recorders linked to satellites, and suspended in choice areas of forest, and near areas of human exploitation, can pick up subtle signals of change.

They can measure animal sounds and birdsong from distances of several hundred metres. They can be turned on at required times or used continuously, and they can identify sounds of birds, mammals, insects and amphibians: to make the case, researchers already have a set of multi-year bio-acoustics registers of change in chosen test zones.

Plants make no such noises − but since all animals depend on vegetation in ways that are both general and specific, the sound of animal life would also be indirect evidence of the health and vigour of the green things around them.

Check on intruders

And, if researchers could build a global organisation to host a platform available for such data, this could provide the basis not just for valuable ecological understanding, but for ways of monitoring human behaviour in the forests.

Big business has in many countries committed itself to economic activity without destroying any more forest, but checks on such promises are hard to make. Bio-acoustic monitors however could as easily tune into the sound of a tractor as to a toucan, to a chainsaw as to the chatter of monkeys, to the sound of a poacher’s gun as to the screech of a parrot.

“Companies are adopting zero deforestation commitments, but these policies do not always translate to protecting biodiversity due to hunting, habitat degradation, and sub-canopy fires,” said Rhett Butler, one of the authors, and founder of Mongabay.com.

“Bioacoustic monitoring could be used to augment satellites and other systems to monitor compliance with these commitments, support real-time action against prohibited activities like illegal logging and poaching, and potentially document habitat and species recovery.” − Climate News Network

Remote sensing by satellites and sound recorders could yield answers to complex global questions and reveal what is happening in the world’s great forests.

LONDON, 9 January, 2019 − High tech answers using satellites and sound recorders could contribute to solving the global information crisis. To check on progress towards world development and conservation goals, researchers could exploit the highest technology of all.

Satellite data and number-crunching computer analysis could identify the world’s poorest households, and those on the way to new hope. And subtle listening devices planted in primal rainforest and near human settlements could provide a low-cost, high-speed check on biodiversity loss and conservation efforts in the developing world.

In effect, researchers argue in two entirely separate studies, the look-and-listen approach could deliver effective levels of information at relatively low expense, and keep nations and international monitoring organisations informed on issues ultimately inseparable from climate change driven by human appropriation of the planet’s resources.

At the heart of each is the search for a sustainable way of monitoring sustainable development. The governments of 93 nations have committed themselves to the UN’s sustainable development goals, to help lift their citizens out of poverty while maintaining the natural resources on which they must rely.

“When we use space data with a socio-ecological insight, we capture the financial status and, in this way, also the development in an area much better”

Danish, British and US researchers report in the Proceedings of the National Academy of Sciences that if social scientists were to rely on traditional methods of research − house-to-house surveys and questionnaires of sample populations on an annual basis and so on − the cost could add up, over the lifetime of the programme, to $253 billion. This is almost twice what the world spent on global development assistance in 2013.

But satellite studies, already massed for other purposes, could hold most of the answers in fine detail already. “Based on high resolution satellite images, we can very precisely assess the poverty at household level in rural areas in developing countries,” said Jens-Christian Svenning, a bioscientist at Aarhus University in Denmark.

“The method that we have developed is designed to analyse the satellite images in a way that takes into account that people have access to and use different resources in the landscape at different levels,” he said.

“Some use the area just around their house, while others use the common areas of a village. When we use space data with a socio-ecological insight, we capture the financial status and, in this way, also the development in an area much better than we have previously been able to.”

Better prospects

There are 17 declared sustainable development goals that could, by 2030, make the world a better place for the people of the poorest countries, without loss of the wildlife around them and without adding to the profligate use of fossil fuels to deliver the energy to fuel potentially catastrophic global warming along with economic growth.

The Aarhus team has already tested their approach in rural western Kenya, to confirm that satellite data could account for 62% of the variation in household wealth: the size of buildings within one homestead, the amount of bare ground within it and the size of the agricultural land around it − and the length of the growing season − were enough to answer important questions.

And since the body of data available from satellite observation is continuously growing, this would offer a substitute for on-the-ground annual monitoring visits, which, they say, would be “prohibitively expensive.”

Within the same week, US and Australian scientists argue in the journal Science for a simple, bio-acoustics approach to ways of measuring and monitoring conservation efforts in the world’s tropical forests.

Listening in

These could yield treasuries of information. Important ecological data could be recovered from what they call “soundscapes” of animal and human activity in the vast tracts of forest that provide a home for most of the world’s terrestrial species, while at the same time drawing down carbon dioxide from the atmosphere and turning it into timber to slow the seemingly-inexorable rise in greenhouse gas concentrations that has already lifted global average temperatures by 1°C, reachimg perhaps a devastating 3°C increase by the end of the century.

Satellite images can answer questions about the loss of forests on a wide scale. But these cannot easily identify other problems, among them overhunting, fires or invasion by exotic species. And field surveys are costly, time-consuming and possible only over small samples of forest. But sound-recorders linked to satellites, and suspended in choice areas of forest, and near areas of human exploitation, can pick up subtle signals of change.

They can measure animal sounds and birdsong from distances of several hundred metres. They can be turned on at required times or used continuously, and they can identify sounds of birds, mammals, insects and amphibians: to make the case, researchers already have a set of multi-year bio-acoustics registers of change in chosen test zones.

Plants make no such noises − but since all animals depend on vegetation in ways that are both general and specific, the sound of animal life would also be indirect evidence of the health and vigour of the green things around them.

Check on intruders

And, if researchers could build a global organisation to host a platform available for such data, this could provide the basis not just for valuable ecological understanding, but for ways of monitoring human behaviour in the forests.

Big business has in many countries committed itself to economic activity without destroying any more forest, but checks on such promises are hard to make. Bio-acoustic monitors however could as easily tune into the sound of a tractor as to a toucan, to a chainsaw as to the chatter of monkeys, to the sound of a poacher’s gun as to the screech of a parrot.

“Companies are adopting zero deforestation commitments, but these policies do not always translate to protecting biodiversity due to hunting, habitat degradation, and sub-canopy fires,” said Rhett Butler, one of the authors, and founder of Mongabay.com.

“Bioacoustic monitoring could be used to augment satellites and other systems to monitor compliance with these commitments, support real-time action against prohibited activities like illegal logging and poaching, and potentially document habitat and species recovery.” − Climate News Network

Nine vital signs found for forest health

Forests help to moderate climate change, which can itself affect forest health. Researchers still puzzle over how the canopy affects the global carbon exchange.

LONDON, 3 January, 2019 – It is a given of climate science that forest health, the consequence of protected and biodiverse forests, will play a vital role in containing global warming. Now a new study for the first time offers foresters, botanists and conservationists the tools to test the health of a vast woodland.

And a second, separate study confirms an ominous discovery: trees can be counted upon to greedily consume ever more atmospheric carbon dioxide – but only while the natural supply of nitrogen holds out.

Trees use photosynthesis to build tissue from atmospheric carbon dioxide, and store the carbon in the form of leaves, fruits and timber while respiring oxygen. In doing so, they reduce levels of global warming.

Humans – by clearing forests, ploughing fields, grazing cattle and burning fossil fuels – tip about 34 billion tonnes of the greenhouse gas carbon dioxide into the atmosphere each year, and the world’s trees take up an estimated 11 bn tonnes of it. But quite how, and how reliably, forests store carbon is still a puzzle.

“The limes, planes, magnolias and poplars that line boulevards and shade city parks could be just as significant to carbon budget calculations as tropical rainforests”

US researchers report in the Proceedings of the National Academy of Sciences that they decided to find out. They analysed data from 421 plots of forest around the world, and took direct samples in 66 of them. They measured temperature, rainfall, vapour pressure, sunlight and wind speed.

Their search spanned 100 degrees of latitude and more than 3,300 metres in altitude. Altogether the scientists gathered information on 55,983 individual trees greater than 2 cms in diameter and divided into 2,701 tree species.

By the time they had finished they had identified nine vital signs that might help with a diagnosis of a forest’s health. These are two different measures of leaf area, as well as wood density, tree height, the counts of leaf carbon, nitrogen and phosphorus and the important ratio of nitrogen to phosphorus.

Armed with these measures, they began to look at precisely how climate might affect a tree population. Two climatic factors in particular had a disproportionate impact.

New pointers

One was temperature variability – that is, the swing from the lowest to the highest mercury levels – and the other was vapour pressure. And they confirmed that, overall, the measured traits are responding to overall global warming.

Such research offers a new set of signposts for understanding how atmosphere, climate and forests interact. The response of the woodlands has become one of the big unresolved questions.

Researchers have found, a little to their surprise, the “urban forests” – the limes, planes, magnolias and poplars that line boulevards and shade city parks – could be just as significant to carbon budget calculations as tropical rainforests.

They have measured unexpected ways in which trees have responded to the rise of 1°C in global average temperatures in the last century, as carbon dioxide levels in the atmosphere have soared from around 280 parts per million to more than 400 ppm.

Concern over nitrogen

But they have also taken serious stock of the planet’s cover of trees, to find that humans are destroying trees at the rate of 15 billion a year and that climate change and human intrusion pose the threat of extinction to many of the world’s 40,000 tropical tree species.

A second team of the US researchers is now sure of one of the mechanisms that might affect the overall health of forests in a warming world. They report in the journal Nature Ecology and Evolution on an intensive examination of the response of 15,000 trees in the wilds of West Virginia to a steady rise in atmospheric carbon dioxide.

Yes, the extra greenhouse gas is fertilising forest growth. But climate change is extending the growing season, as spring arrives earlier and autumn leaf fall happens ever later. A study of the nitrogen isotopes in the leaves suggests that the supply of that other, all-important nutrient, could be on the way down.

If so, the growth of the forests could soon peak, and with that the capacity of forests to moderate climate change could diminish. – Climate News Network

Forests help to moderate climate change, which can itself affect forest health. Researchers still puzzle over how the canopy affects the global carbon exchange.

LONDON, 3 January, 2019 – It is a given of climate science that forest health, the consequence of protected and biodiverse forests, will play a vital role in containing global warming. Now a new study for the first time offers foresters, botanists and conservationists the tools to test the health of a vast woodland.

And a second, separate study confirms an ominous discovery: trees can be counted upon to greedily consume ever more atmospheric carbon dioxide – but only while the natural supply of nitrogen holds out.

Trees use photosynthesis to build tissue from atmospheric carbon dioxide, and store the carbon in the form of leaves, fruits and timber while respiring oxygen. In doing so, they reduce levels of global warming.

Humans – by clearing forests, ploughing fields, grazing cattle and burning fossil fuels – tip about 34 billion tonnes of the greenhouse gas carbon dioxide into the atmosphere each year, and the world’s trees take up an estimated 11 bn tonnes of it. But quite how, and how reliably, forests store carbon is still a puzzle.

“The limes, planes, magnolias and poplars that line boulevards and shade city parks could be just as significant to carbon budget calculations as tropical rainforests”

US researchers report in the Proceedings of the National Academy of Sciences that they decided to find out. They analysed data from 421 plots of forest around the world, and took direct samples in 66 of them. They measured temperature, rainfall, vapour pressure, sunlight and wind speed.

Their search spanned 100 degrees of latitude and more than 3,300 metres in altitude. Altogether the scientists gathered information on 55,983 individual trees greater than 2 cms in diameter and divided into 2,701 tree species.

By the time they had finished they had identified nine vital signs that might help with a diagnosis of a forest’s health. These are two different measures of leaf area, as well as wood density, tree height, the counts of leaf carbon, nitrogen and phosphorus and the important ratio of nitrogen to phosphorus.

Armed with these measures, they began to look at precisely how climate might affect a tree population. Two climatic factors in particular had a disproportionate impact.

New pointers

One was temperature variability – that is, the swing from the lowest to the highest mercury levels – and the other was vapour pressure. And they confirmed that, overall, the measured traits are responding to overall global warming.

Such research offers a new set of signposts for understanding how atmosphere, climate and forests interact. The response of the woodlands has become one of the big unresolved questions.

Researchers have found, a little to their surprise, the “urban forests” – the limes, planes, magnolias and poplars that line boulevards and shade city parks – could be just as significant to carbon budget calculations as tropical rainforests.

They have measured unexpected ways in which trees have responded to the rise of 1°C in global average temperatures in the last century, as carbon dioxide levels in the atmosphere have soared from around 280 parts per million to more than 400 ppm.

Concern over nitrogen

But they have also taken serious stock of the planet’s cover of trees, to find that humans are destroying trees at the rate of 15 billion a year and that climate change and human intrusion pose the threat of extinction to many of the world’s 40,000 tropical tree species.

A second team of the US researchers is now sure of one of the mechanisms that might affect the overall health of forests in a warming world. They report in the journal Nature Ecology and Evolution on an intensive examination of the response of 15,000 trees in the wilds of West Virginia to a steady rise in atmospheric carbon dioxide.

Yes, the extra greenhouse gas is fertilising forest growth. But climate change is extending the growing season, as spring arrives earlier and autumn leaf fall happens ever later. A study of the nitrogen isotopes in the leaves suggests that the supply of that other, all-important nutrient, could be on the way down.

If so, the growth of the forests could soon peak, and with that the capacity of forests to moderate climate change could diminish. – Climate News Network

Extinction toll may be far worse than thought

Yet again, researchers have confirmed that climate change threatens the natural world with a soaring extinction toll. The danger may be much higher than anyone imagined.

LONDON, 11 December, 2018 − Two scientists want the world to think again about the extinction toll, the rate at which species could vanish as the planet warms. They warn that the worst fears so far may have been based on underestimates. Tomorrow’s rates of extinction could be 10 times worse.

That is because the loss of one or two key species could turn into a cascade that could spell the end for whole ecosystems. “Primary extinctions driven by environmental change could be just the tip of an enormous extinction iceberg,” they warn.

In their study, long before the complete loss of one species, other species locked into the same ecosystem started to perish. There is no need to worry about the rare but real hazard of an asteroid impact, or a burst of gamma rays from a nearby exploding star. The message from the simulators is that global average warming of between 5° and 6°C above the level for most of history since the end of the last Ice Age would be enough to wipe out most life on the hypothetical Earths.

“This makes it difficult to be optimistic about the future of species diversity in the ongoing trajectory of global change, let alone in the case of additional external, extraplanetary catastrophes.”

Giovanni Strona of the European Commission’s joint research centre in Ispra, Italy and Corey Bradshaw of Finders University in Adelaide, Australia write in the journal Scientific Reports that they turned to computer simulation to resolve an enduring ecological question: quite what is it that drives biodiversity loss?

“Whenever a species leaves our planet, we lose much more than a name on a list”

The growth in human numbers, and the exploitation of the planet’s surface for economic growth, has destroyed habitats and disrupted ecosystems on a scale without parallel: global warming and climate change will make things worse.

Researchers have confirmed, repeatedly, that ecosystems are under threat; that climate change could be even more damaging than anyone suspected; that half of 976 species in one study were already being extinguished in local ecosystems, even if they survived elsewhere as the thermometer rose.

But most such studies were based on sample examinations of specific patches of woodland, grassland, marsh or lake, or surveys of published literature, and they measured change in a planet that has – since the beginning of the Industrial Revolution – warmed by about 1°C as a consequence of profligate combustion of fossil fuels and the clearance of the great forests. The latest study involved testing life on a planet to destruction.

The two scientists constructed 2,000 “virtual Earths” and populated them with interacting species: that is with a food web composed of competing predators and prey, multiple consumers and consumed. Then they subjected these notional biospheres to extreme environmental change, ranging from runaway global warming driven by ever-greater greenhouse gas emissions to the sudden, intense cooling of a “nuclear winter” in which sunlight is blocked by the dust of global thermonuclear war.

And the experiments, they say, demonstrated, once again, the co-dependency of living things in a stable environment. They set up two scenarios. In one of them a species was subjected to temperature change to the point of extinction. In the other, the researchers triggered a series of co-extinction cascades. They then matched the two outcomes.

More than species

And they found that failure to take into account the complex, entangled interdependencies of living things led to an underestimate, by 10 times, of the magnitude of mass extinction by climate change alone. The message is: don’t just save the giant panda, save the forest.

“Conservationists and decision makers need to move fast beyond a species-specific approach, and look with increasing attention at interaction networks as a fundamental conservation target,” Dr Strona said. “Whenever a species leaves our planet, we lose much more than a name on a list.”

Other such simulations have delivered catastrophic conclusions: one examination of runaway global warming left the Earth uninhabitable, while another found that in the most dreadful outcomes, at least one life form, the tardigrade, might survive.

Any computer model of life on Earth must have its weaknesses, if only because the unknown and unnamed list of creatures is at least 10 times greater than those already catalogued in the world’s botanical gardens, zoos and natural history museums. That is, biologists still don’t know nearly enough about the diversity of life on Earth. There are, the researchers concede, “obvious limitations in our ambitions model.”

But, said Dr Strona: “Our results are consistent with real-world patterns for which we have empirical evidence. This makes us confident that the many assumptions we had to take in order to build a functional model are sound. On the other hand, it would be misleading to just focus on raw numbers.” − Climate News Network

Yet again, researchers have confirmed that climate change threatens the natural world with a soaring extinction toll. The danger may be much higher than anyone imagined.

LONDON, 11 December, 2018 − Two scientists want the world to think again about the extinction toll, the rate at which species could vanish as the planet warms. They warn that the worst fears so far may have been based on underestimates. Tomorrow’s rates of extinction could be 10 times worse.

That is because the loss of one or two key species could turn into a cascade that could spell the end for whole ecosystems. “Primary extinctions driven by environmental change could be just the tip of an enormous extinction iceberg,” they warn.

In their study, long before the complete loss of one species, other species locked into the same ecosystem started to perish. There is no need to worry about the rare but real hazard of an asteroid impact, or a burst of gamma rays from a nearby exploding star. The message from the simulators is that global average warming of between 5° and 6°C above the level for most of history since the end of the last Ice Age would be enough to wipe out most life on the hypothetical Earths.

“This makes it difficult to be optimistic about the future of species diversity in the ongoing trajectory of global change, let alone in the case of additional external, extraplanetary catastrophes.”

Giovanni Strona of the European Commission’s joint research centre in Ispra, Italy and Corey Bradshaw of Finders University in Adelaide, Australia write in the journal Scientific Reports that they turned to computer simulation to resolve an enduring ecological question: quite what is it that drives biodiversity loss?

“Whenever a species leaves our planet, we lose much more than a name on a list”

The growth in human numbers, and the exploitation of the planet’s surface for economic growth, has destroyed habitats and disrupted ecosystems on a scale without parallel: global warming and climate change will make things worse.

Researchers have confirmed, repeatedly, that ecosystems are under threat; that climate change could be even more damaging than anyone suspected; that half of 976 species in one study were already being extinguished in local ecosystems, even if they survived elsewhere as the thermometer rose.

But most such studies were based on sample examinations of specific patches of woodland, grassland, marsh or lake, or surveys of published literature, and they measured change in a planet that has – since the beginning of the Industrial Revolution – warmed by about 1°C as a consequence of profligate combustion of fossil fuels and the clearance of the great forests. The latest study involved testing life on a planet to destruction.

The two scientists constructed 2,000 “virtual Earths” and populated them with interacting species: that is with a food web composed of competing predators and prey, multiple consumers and consumed. Then they subjected these notional biospheres to extreme environmental change, ranging from runaway global warming driven by ever-greater greenhouse gas emissions to the sudden, intense cooling of a “nuclear winter” in which sunlight is blocked by the dust of global thermonuclear war.

And the experiments, they say, demonstrated, once again, the co-dependency of living things in a stable environment. They set up two scenarios. In one of them a species was subjected to temperature change to the point of extinction. In the other, the researchers triggered a series of co-extinction cascades. They then matched the two outcomes.

More than species

And they found that failure to take into account the complex, entangled interdependencies of living things led to an underestimate, by 10 times, of the magnitude of mass extinction by climate change alone. The message is: don’t just save the giant panda, save the forest.

“Conservationists and decision makers need to move fast beyond a species-specific approach, and look with increasing attention at interaction networks as a fundamental conservation target,” Dr Strona said. “Whenever a species leaves our planet, we lose much more than a name on a list.”

Other such simulations have delivered catastrophic conclusions: one examination of runaway global warming left the Earth uninhabitable, while another found that in the most dreadful outcomes, at least one life form, the tardigrade, might survive.

Any computer model of life on Earth must have its weaknesses, if only because the unknown and unnamed list of creatures is at least 10 times greater than those already catalogued in the world’s botanical gardens, zoos and natural history museums. That is, biologists still don’t know nearly enough about the diversity of life on Earth. There are, the researchers concede, “obvious limitations in our ambitions model.”

But, said Dr Strona: “Our results are consistent with real-world patterns for which we have empirical evidence. This makes us confident that the many assumptions we had to take in order to build a functional model are sound. On the other hand, it would be misleading to just focus on raw numbers.” − Climate News Network

Tropical forests flee uphill to escape heat

The tropical forests of the Andes are responding to climate change. But a tree can climb only so far before it has nowhere to go.

LONDON, 22 November, 2018 − Tropical forests are racing uphill to escape global warming. Some of them may lose the race.

A meticulous and sustained study of nearly 200 plots of forest in Colombia, Ecuador, Peru and northern Argentina has found that where they can, tropical species are moving uphill as the thermometer rises. But there is a problem: can a species that flourished in one ecosystem in the Andes and Amazon migrate and colonise another at higher altitude?

A new study in the journal Nature finds that some of them cannot. “Andean forests must be added to the growing list of ecosystems and species that lack the ability to quickly and cohesively respond to climate change and thus face high risk of extinction, biodiversity loss and functional collapse,” they conclude.

Plants and animals in mountain communities everywhere in the temperate world seem to be on the move: many of the studies however focus on observations of selected species in one country or mountain zone, or even on one mountain.

Wider perspective

Belén Fabrique and Kenneth Feeley of the University of Miami and colleagues went looking for the big picture. They selected 186 closely-monitored tracts of forest in what scientists call the Tropical Andes Biodiversity Hotspot, at altitudes of from 300 to 3,000 metres. These forest plots together are home to 120 different plant families divided into 528 genera and 2,024 tree named species, including palms, tree ferns and lianas.

They then looked for a way to measure change in a mix of such diversity − in effect, a local ecosystem − and selected a measure called the community temperature index, already used to monitor shifts in bird and butterfly populations elsewhere. Since most of the plots had been surveyed each year over a 20-year period, they had a way of detecting and tracking change.

Temperate species of trees are adapted to big seasonal shifts in temperature. Trees in the lowland tropics are not. Tropical trees that migrate uphill run the risk of encountering an environmental roadblock, a shift in the ecosystem.

“In the Andes, the ecosystems can change very fast and very dramatically, for example from sunny and dry premontane forests to sopping wet cloud forests. These changes, called ecotones, appear to be blocking species migrations,” said Belén Fabrique, who designed the study.

“The faster climate change happens, the faster we will lose our tropical forests, which means that climate change will happen even faster”

“These ecotone barriers make it harder for plants to relocate their populations – and if they can’t relocate, they will go extinct.”

In response to climate change – driven by ever-higher emissions of greenhouse gases from the combustion of fossil fuels – the researchers confirmed that the thermophilic or heat-loving species were shifting to higher ground, while the abundance of the species adapted to cool conditions was declining. But the rate of change in the mix of these forest plots was not uniform: some Andean species were being driven out as rainfall and cloud cover conditions became intolerable.

“Thermophilisation is a mouthful of a word but it means that forests are becoming more heat-loving over time because as the world warms up, the species that prefer cold are being kicked out or are dying off and the heat-loving species are moving up and taking their place,” said Professor Feeley.

“Everything is moving up the mountain, so the species near the tops of the mountains are running out of places to go and may soon face the risk of mountain-top extinction.”

Taxonomical logjam

The next step is to try to work out how climate operates on specific Andean plants: a challenge because many of them have yet to be identified and named. Only then can researchers work out the ecological consequences of their loss.

The irony is that forest ecosystems play a key role in moderating climate change.

“Tropical forests are one of the most important players in the world’s global carbon cycle. They slow down climate change by taking a lot of carbon out of the atmosphere and putting it into their growth,” Professor Feeley said.

“So the faster climate change happens, the faster we will lose our tropical forests, which means that climate change will happen even faster.” – Climate News Network

The tropical forests of the Andes are responding to climate change. But a tree can climb only so far before it has nowhere to go.

LONDON, 22 November, 2018 − Tropical forests are racing uphill to escape global warming. Some of them may lose the race.

A meticulous and sustained study of nearly 200 plots of forest in Colombia, Ecuador, Peru and northern Argentina has found that where they can, tropical species are moving uphill as the thermometer rises. But there is a problem: can a species that flourished in one ecosystem in the Andes and Amazon migrate and colonise another at higher altitude?

A new study in the journal Nature finds that some of them cannot. “Andean forests must be added to the growing list of ecosystems and species that lack the ability to quickly and cohesively respond to climate change and thus face high risk of extinction, biodiversity loss and functional collapse,” they conclude.

Plants and animals in mountain communities everywhere in the temperate world seem to be on the move: many of the studies however focus on observations of selected species in one country or mountain zone, or even on one mountain.

Wider perspective

Belén Fabrique and Kenneth Feeley of the University of Miami and colleagues went looking for the big picture. They selected 186 closely-monitored tracts of forest in what scientists call the Tropical Andes Biodiversity Hotspot, at altitudes of from 300 to 3,000 metres. These forest plots together are home to 120 different plant families divided into 528 genera and 2,024 tree named species, including palms, tree ferns and lianas.

They then looked for a way to measure change in a mix of such diversity − in effect, a local ecosystem − and selected a measure called the community temperature index, already used to monitor shifts in bird and butterfly populations elsewhere. Since most of the plots had been surveyed each year over a 20-year period, they had a way of detecting and tracking change.

Temperate species of trees are adapted to big seasonal shifts in temperature. Trees in the lowland tropics are not. Tropical trees that migrate uphill run the risk of encountering an environmental roadblock, a shift in the ecosystem.

“In the Andes, the ecosystems can change very fast and very dramatically, for example from sunny and dry premontane forests to sopping wet cloud forests. These changes, called ecotones, appear to be blocking species migrations,” said Belén Fabrique, who designed the study.

“The faster climate change happens, the faster we will lose our tropical forests, which means that climate change will happen even faster”

“These ecotone barriers make it harder for plants to relocate their populations – and if they can’t relocate, they will go extinct.”

In response to climate change – driven by ever-higher emissions of greenhouse gases from the combustion of fossil fuels – the researchers confirmed that the thermophilic or heat-loving species were shifting to higher ground, while the abundance of the species adapted to cool conditions was declining. But the rate of change in the mix of these forest plots was not uniform: some Andean species were being driven out as rainfall and cloud cover conditions became intolerable.

“Thermophilisation is a mouthful of a word but it means that forests are becoming more heat-loving over time because as the world warms up, the species that prefer cold are being kicked out or are dying off and the heat-loving species are moving up and taking their place,” said Professor Feeley.

“Everything is moving up the mountain, so the species near the tops of the mountains are running out of places to go and may soon face the risk of mountain-top extinction.”

Taxonomical logjam

The next step is to try to work out how climate operates on specific Andean plants: a challenge because many of them have yet to be identified and named. Only then can researchers work out the ecological consequences of their loss.

The irony is that forest ecosystems play a key role in moderating climate change.

“Tropical forests are one of the most important players in the world’s global carbon cycle. They slow down climate change by taking a lot of carbon out of the atmosphere and putting it into their growth,” Professor Feeley said.

“So the faster climate change happens, the faster we will lose our tropical forests, which means that climate change will happen even faster.” – Climate News Network

Biofuel land grab will slash nature’s space

Growing enough greenery to provide cleaner fuel and slow climate change will need a biofuel land grab: a 10 to 30-fold rise in land devoted to green crops.

LONDON, 21 November, 2018 − Replacing fossil fuels with alternatives derived from some natural sources may be prohibitively high: the biofuel land grab needed could require at least 10% more land than the world uses now to grow green crops, conservationists say.

But that’s the good news. They believe the total increase in green energy-related land use could be much higher, closer to 30%, meaning “crushing” pressure on habitats for plants and animals, and undermining the essential diversity of species on Earth.

Their warning was spelt out at a UN biodiversity meeting in Egypt by Anne Larigauderie, executive secretary of the Intergovernmental Platform on Biodiversity and Ecosystem Services, IPBES.

IPBES says it exists to organise knowledge about the Earth’s biodiversity to offer information for political decisions globally, like the work over the last 30 years of the Intergovernmental Panel on Climate Change, the IPCC.

Extremely urgent

She said the latest IPCC report, on limiting climate warming to 1.5°C, had given “a sense of extreme urgency for these exchanges on tradeoffs and synergies between climate, biodiversity and land degradation.”

Dr. Larigauderie said most IPCC scenarios foresaw a major increase in the land area needed to cultivate biofuel crops like maize (or corn, as it is also known) to slow the pace of warming by 2050 − up to 724 million hectares in total, an area almost the size of Australia. The current amount of land used for biofuel crops is uncertain, but conservationists say it lies somewhere between 15 and 30m ha.

“The key issue here is: where would this huge amount of new land come from”, she asked. “Is there currently such a large amount of ‘marginal land’ available or would this compete with biodiversity? Some scientists argue that there is very little marginal land left.

“Protecting the invaluable contributions of nature to people will be the defining challenge of decades to come”

“This important issue needs to be clarified, but the demand for land for energy will almost certainly increase, with negative consequences for biodiversity.”

Dr. Larigauderie was speaking at the start of the annual conference of the states which support the UN Convention on Biological Diversity.

Deep cuts in the greenhouse gas emissions from human activities which drive global warming would be possible without massive bioenergy resources, she said, but this would need substantial cuts in energy use as well as rapid increases in the production of low-carbon energy from wind, solar and nuclear power.

Safeguarding the variety of plant and animal species and the services nature provides was itself essential to reducing global warming, she said. Land ecosystems today soak up about a third of annual carbon dioxide emissions, with the world’s oceans accounting for about another quarter annually.

Forests achieve more

In any case, Dr Larigauderie said, reforestation was better at protecting the climate than most biofuel crops. In temperate climates, one reforested hectare was four times more effective in climate mitigation than a hectare of maize used for biofuel.

“All methods that produce healthier ecosystems should be promoted as a way to combat climate change”, she said. “This includes afforestation and reforestation, as well as restoration − implemented properly using native species, for example.”

IPBES plans to publish a primer detailing elements of its Global Assessment of Biodiversity in May 2019. The British scientist Sir Robert Watson, formerly chair of the IPCC and now chair of IPBES, says: “The loss of species, ecosystems and genetic diversity is already a global and generational threat to human well-being. Protecting the invaluable contributions of nature to people will be the defining challenge of decades to come.

“Policies, efforts and actions − at every level − will only succeed, however, when based on the best knowledge and evidence. This is what the IPBES Global Assessment provides.” − Climate News Network

Growing enough greenery to provide cleaner fuel and slow climate change will need a biofuel land grab: a 10 to 30-fold rise in land devoted to green crops.

LONDON, 21 November, 2018 − Replacing fossil fuels with alternatives derived from some natural sources may be prohibitively high: the biofuel land grab needed could require at least 10% more land than the world uses now to grow green crops, conservationists say.

But that’s the good news. They believe the total increase in green energy-related land use could be much higher, closer to 30%, meaning “crushing” pressure on habitats for plants and animals, and undermining the essential diversity of species on Earth.

Their warning was spelt out at a UN biodiversity meeting in Egypt by Anne Larigauderie, executive secretary of the Intergovernmental Platform on Biodiversity and Ecosystem Services, IPBES.

IPBES says it exists to organise knowledge about the Earth’s biodiversity to offer information for political decisions globally, like the work over the last 30 years of the Intergovernmental Panel on Climate Change, the IPCC.

Extremely urgent

She said the latest IPCC report, on limiting climate warming to 1.5°C, had given “a sense of extreme urgency for these exchanges on tradeoffs and synergies between climate, biodiversity and land degradation.”

Dr. Larigauderie said most IPCC scenarios foresaw a major increase in the land area needed to cultivate biofuel crops like maize (or corn, as it is also known) to slow the pace of warming by 2050 − up to 724 million hectares in total, an area almost the size of Australia. The current amount of land used for biofuel crops is uncertain, but conservationists say it lies somewhere between 15 and 30m ha.

“The key issue here is: where would this huge amount of new land come from”, she asked. “Is there currently such a large amount of ‘marginal land’ available or would this compete with biodiversity? Some scientists argue that there is very little marginal land left.

“Protecting the invaluable contributions of nature to people will be the defining challenge of decades to come”

“This important issue needs to be clarified, but the demand for land for energy will almost certainly increase, with negative consequences for biodiversity.”

Dr. Larigauderie was speaking at the start of the annual conference of the states which support the UN Convention on Biological Diversity.

Deep cuts in the greenhouse gas emissions from human activities which drive global warming would be possible without massive bioenergy resources, she said, but this would need substantial cuts in energy use as well as rapid increases in the production of low-carbon energy from wind, solar and nuclear power.

Safeguarding the variety of plant and animal species and the services nature provides was itself essential to reducing global warming, she said. Land ecosystems today soak up about a third of annual carbon dioxide emissions, with the world’s oceans accounting for about another quarter annually.

Forests achieve more

In any case, Dr Larigauderie said, reforestation was better at protecting the climate than most biofuel crops. In temperate climates, one reforested hectare was four times more effective in climate mitigation than a hectare of maize used for biofuel.

“All methods that produce healthier ecosystems should be promoted as a way to combat climate change”, she said. “This includes afforestation and reforestation, as well as restoration − implemented properly using native species, for example.”

IPBES plans to publish a primer detailing elements of its Global Assessment of Biodiversity in May 2019. The British scientist Sir Robert Watson, formerly chair of the IPCC and now chair of IPBES, says: “The loss of species, ecosystems and genetic diversity is already a global and generational threat to human well-being. Protecting the invaluable contributions of nature to people will be the defining challenge of decades to come.

“Policies, efforts and actions − at every level − will only succeed, however, when based on the best knowledge and evidence. This is what the IPBES Global Assessment provides.” − Climate News Network

Climate impacts will seldom strike singly

Climate impacts aren’t just potentially catastrophic: they could be simultaneous multiple disasters. US scientists have compiled a catalogue of calamity and a map of mayhem.

LONDON, 20 November, 2019 − By 2100, climate impacts will be felt by everyone and most people will experience at least three simultaneous hazards, inexorably made more hazardous by the build-up of greenhouse gases in the atmosphere.

And they could be the lucky ones: some people could be menaced by six different kinds of warming-related hazard simultaneously.

Camilo Mora of the University of Hawaii at Manoa and 22 colleagues report in Nature Climate Change that they read systematically through 3,280 peer-reviewed papers on the subject of climate change, and compiled a matrix of 467 ways in which 10 major climate hazards – floods, droughts, heat waves, fires and so on – and six aspects of human dependency (health, food, water, etc.) could affect humanity.

They did, they say, identify some positive or neutral effects, but the overwhelming majority of climate impacts would create problems for human communities and their economies.

Medical prospects

Dr Mora has established a reputation for thinking on the scale of global catalogue. Recently, the geographer and his fellow researchers looked at medical records and heat extremes and listed 27 different ways in which heat waves could kill.

In recent years he has been involved in studies that have tried to measure the challenge to the global harvest because of carbon dioxide accretion in the atmosphere as a consequence of fossil fuel combustion; the first years in which particular locations around the world could feel the impact of irreversible climate change; and then the proportion of humans at risk from heat extremes by the end of the century.

The latest study concludes that even if greenhouse gas emissions are dramatically reduced, most of the world would still be confronted by one hazard at a time: the worldwide average temperature rise of 1°C has already started to change climates and heighten climatic extremes.

And if humans go on burning fossil fuels in what has become notorious as the business-as-usual scenario, then almost everybody could face three hazards at the same time. In some coastal regions some people could be hit by six.

“The evidence of climate change impacting humanity is abundant, loud and clear … How many wake-up calls will it take to wake up?”

Higher atmospheric temperatures accelerate the evaporation of soil water. Normally dry places will be at risk of drought, heatwave and wildfire. Normally rainy places will face catastrophic downpour, and flood. Warmer ocean waters will evaporate at greater rates, so windspeed and rainfall from hurricanes will also increase. Sea level rise driven by water temperatures, and by glacial melting, will raise the risk of coastal flooding and storm surges.

Some of these impacts have already affected human health, bringing death, disease and mental illness. They have affected the supply of food on land and at sea; they have damaged electrical supplies, transportation, water and sewage infrastructure; they have damaged property and reduced labour productivity; they have triggered migration and sparked violence, and Dr Mora and his colleagues have now compiled a database of more than 3,000 documented examples.

“Greenhouse gas emissions pose a broad threat to humanity by simultaneously intensifying many hazards that have proved harmful in the past,” said Dr Mora.

“Further, we predict that by 2100 the number of hazards occurring concurrently will increase, making it even more difficult for people to cope.”

List of impacts

The latest study simply looks at all the recent climate impacts recorded and assessed and categorises them in a range of ways.

These include the 33% loss of grain to drought and fire in Russia in 2010; the loss of three-fourths of all livestock during drought in Kenya in 2000; drinking water shortages for 33 million people in China in 2001; the rise in waterborne infectious diseases after the 2010 Indus floods overwhelmed sewage treatment plants in Pakistan; the cumulative damage by flood and storm to millions of homes in China, Pakistan, Bangladesh, Indonesia, the US and France; and – because of melting ice – the forced relocation of Inuit villages in Alaska.

Heatwaves caused blackouts for 670 million people in India in 2012, and 35 million in Saudi Arabia in 2010. After Hurricane Andrew in 1992 hammered the US east coast, a total of 12 insurance companies went bust.

The next step, having assembled the possible kinds of impact, was to model the way they would be amplified and intensified under various scenarios for global warming. Wealth and economic power offer no great protection. New York can expect at worst by 2100 to face at least four hazards; Sydney and Los Angeles three; Mexico City four, and the Atlantic coast of Brazil five.

Present danger

“The collision of cumulative climate hazards is not something on the horizon, it is already here,” Dr Mora said. “Co-occurring and colliding climate hazards are already making headlines worldwide.

“Last year, for instance, Florida recorded extreme drought, record high temperatures, over 100 wildfires, and the strongest-ever recorded hurricane in its Panhandle: the category 4 Hurricane Michael.

“Likewise, California is currently experiencing ferocious wild fires and one of the longest droughts, plus extreme heatwaves this past summer.”

“The evidence of climate change impacting humanity is abundant, loud and clear”, said his co-author and colleague Daniele Spirandelli. “Clearly, the outstanding question is − how many wake-up calls will it take to wake up?” − Climate News Network

Climate impacts aren’t just potentially catastrophic: they could be simultaneous multiple disasters. US scientists have compiled a catalogue of calamity and a map of mayhem.

LONDON, 20 November, 2019 − By 2100, climate impacts will be felt by everyone and most people will experience at least three simultaneous hazards, inexorably made more hazardous by the build-up of greenhouse gases in the atmosphere.

And they could be the lucky ones: some people could be menaced by six different kinds of warming-related hazard simultaneously.

Camilo Mora of the University of Hawaii at Manoa and 22 colleagues report in Nature Climate Change that they read systematically through 3,280 peer-reviewed papers on the subject of climate change, and compiled a matrix of 467 ways in which 10 major climate hazards – floods, droughts, heat waves, fires and so on – and six aspects of human dependency (health, food, water, etc.) could affect humanity.

They did, they say, identify some positive or neutral effects, but the overwhelming majority of climate impacts would create problems for human communities and their economies.

Medical prospects

Dr Mora has established a reputation for thinking on the scale of global catalogue. Recently, the geographer and his fellow researchers looked at medical records and heat extremes and listed 27 different ways in which heat waves could kill.

In recent years he has been involved in studies that have tried to measure the challenge to the global harvest because of carbon dioxide accretion in the atmosphere as a consequence of fossil fuel combustion; the first years in which particular locations around the world could feel the impact of irreversible climate change; and then the proportion of humans at risk from heat extremes by the end of the century.

The latest study concludes that even if greenhouse gas emissions are dramatically reduced, most of the world would still be confronted by one hazard at a time: the worldwide average temperature rise of 1°C has already started to change climates and heighten climatic extremes.

And if humans go on burning fossil fuels in what has become notorious as the business-as-usual scenario, then almost everybody could face three hazards at the same time. In some coastal regions some people could be hit by six.

“The evidence of climate change impacting humanity is abundant, loud and clear … How many wake-up calls will it take to wake up?”

Higher atmospheric temperatures accelerate the evaporation of soil water. Normally dry places will be at risk of drought, heatwave and wildfire. Normally rainy places will face catastrophic downpour, and flood. Warmer ocean waters will evaporate at greater rates, so windspeed and rainfall from hurricanes will also increase. Sea level rise driven by water temperatures, and by glacial melting, will raise the risk of coastal flooding and storm surges.

Some of these impacts have already affected human health, bringing death, disease and mental illness. They have affected the supply of food on land and at sea; they have damaged electrical supplies, transportation, water and sewage infrastructure; they have damaged property and reduced labour productivity; they have triggered migration and sparked violence, and Dr Mora and his colleagues have now compiled a database of more than 3,000 documented examples.

“Greenhouse gas emissions pose a broad threat to humanity by simultaneously intensifying many hazards that have proved harmful in the past,” said Dr Mora.

“Further, we predict that by 2100 the number of hazards occurring concurrently will increase, making it even more difficult for people to cope.”

List of impacts

The latest study simply looks at all the recent climate impacts recorded and assessed and categorises them in a range of ways.

These include the 33% loss of grain to drought and fire in Russia in 2010; the loss of three-fourths of all livestock during drought in Kenya in 2000; drinking water shortages for 33 million people in China in 2001; the rise in waterborne infectious diseases after the 2010 Indus floods overwhelmed sewage treatment plants in Pakistan; the cumulative damage by flood and storm to millions of homes in China, Pakistan, Bangladesh, Indonesia, the US and France; and – because of melting ice – the forced relocation of Inuit villages in Alaska.

Heatwaves caused blackouts for 670 million people in India in 2012, and 35 million in Saudi Arabia in 2010. After Hurricane Andrew in 1992 hammered the US east coast, a total of 12 insurance companies went bust.

The next step, having assembled the possible kinds of impact, was to model the way they would be amplified and intensified under various scenarios for global warming. Wealth and economic power offer no great protection. New York can expect at worst by 2100 to face at least four hazards; Sydney and Los Angeles three; Mexico City four, and the Atlantic coast of Brazil five.

Present danger

“The collision of cumulative climate hazards is not something on the horizon, it is already here,” Dr Mora said. “Co-occurring and colliding climate hazards are already making headlines worldwide.

“Last year, for instance, Florida recorded extreme drought, record high temperatures, over 100 wildfires, and the strongest-ever recorded hurricane in its Panhandle: the category 4 Hurricane Michael.

“Likewise, California is currently experiencing ferocious wild fires and one of the longest droughts, plus extreme heatwaves this past summer.”

“The evidence of climate change impacting humanity is abundant, loud and clear”, said his co-author and colleague Daniele Spirandelli. “Clearly, the outstanding question is − how many wake-up calls will it take to wake up?” − Climate News Network

Forest carbon storage puzzles scientists

How forest carbon storage affects climate change is a vital part of scientists’ calculations. But fresh uncertainties keep on sprouting.

LONDON, 6 November, 2018 – Two new studies have just made one of the puzzles confronting scientists even more perplexing: just how effective is forest carbon storage?

One research team thinks that their colleagues have been overestimating one of the big calculations of carbon storage: the estimates of atmospheric carbon locked into the timber of the world’s forests may have been systematically overestimated for at least 50 years.

And another has slightly more cheerful news: assumptions about what trees do at night or in the winter could be wrong. Even at night, vegetation is at work, absorbing nitrogen and building tissues with carbon.

Both studies are tentative. The resulting answers do not make a huge difference to the biggest climate puzzle of all: what happens to the carbon dioxide and other greenhouse gases emitted by the combustion of fossil fuels. This is known as the carbon budget.

But both studies are reminders that when it comes to understanding precisely how the planet’s climate machinery works, there are still many questions to be settled.

“No matter what, plants will not keep up with anthropogenic carbon dioxide emissions; it’s just that they might do better than current models suggest”

French scientists report in the American Journal of Botany that they took a new look at an old formula, the forester’s rule of thumb used for calculating the density of wood in growing trees. And, the scientists say, they have found a small mistake: one big enough, however, to lead to an overestimate of up to 5% in the carbon-storing capacity of an oak, a pine, a eucalypt or a fig.

Scientists at CIRAD, an agricultural research base in Montpellier, France, have kept a database of 1,300 wood species and almost 4,500 trees for the last 70 years. When researchers came to look at a conversion factor in calculations of density, they found something that failed to add up.

“To start with, I thought we had made a mistake in our calculations, or that there was some uncertainty surrounding measurement of the relevant data,” said Ghislain Vieilledent of CIRAD. “It was not easy to cast doubt on a formula that has been widely accepted for years and quoted in several scientific articles.”

It means that estimates of the carbon stored in the world’s forests – a vital component of the carbon budget calculations – could be too high by a relatively small factor. But the global sums are huge.

Uncertainties abound

Human industrial activity releases on average 34 billion tonnes of carbon dioxide each year. Land use is seen as a key factor in mitigating the effects of these emissions. The world’s forests are thought to absorb and store up to 11 billion tonnes of carbon dioxide from the atmosphere each year.

Quite how efficiently this happens depends on a huge range of other factors, including the levels of rainfall and the action of soil microbes and fungi. Nobody knows quite how vegetation will react to higher temperatures, higher ratios of carbon dioxide in the atmosphere, or longer droughts or heatwaves.

There are uncertainties about all these factors: an error in estimating the precise density of wood could be just another sprig of doubt in a forest of confusions.

On the other hand, it could be a straightforward finding that forests are now 5% less good at storing carbon than climate scientists have so far assumed.

Nocturnal activity

But any consequent gloom could be countered by another forest revelation, this time in the journal Nature Climate Change.

Scientists at the Lawrence Berkeley National Laboratory have fashioned a new global land model of the traffic between atmosphere, rocks and living things. They report that plants actually take up more carbon dioxide, and soils surrender less of that other greenhouse gas, nitrous oxide, than previously thought.

And they arrived at this conclusion by taking a closer look at what plants do at night.

The assumption is that they do nothing much at night: there is no photosynthesis, so there is no plant action.

Carbon budget queries

But, the US team says, there is evidence that where nutrients are abundant, plants go on taking up nutrients at night, and even in the non-growing season. In the Arctic, this may account for 20% more nitrogen consumption. In the tropics, it may be as high as 55%.

In which case, the carbon budget estimates could be wrong: the error in the calculation of nitrous oxide released could add up to the equivalent of 2.4 billion tonnes of carbon dioxide not spilled into the atmosphere from the forest floor.

“This is goodish news, with respect to what is currently in climate models,” said William Riley of Lawrence Berkeley Laboratory.

“But it is not good news in general – it’s not going to solve the problem. No matter what, plants will not keep up with anthropogenic carbon dioxide emissions; it’s just that they might do better than current models suggest.” – Climate News Network

How forest carbon storage affects climate change is a vital part of scientists’ calculations. But fresh uncertainties keep on sprouting.

LONDON, 6 November, 2018 – Two new studies have just made one of the puzzles confronting scientists even more perplexing: just how effective is forest carbon storage?

One research team thinks that their colleagues have been overestimating one of the big calculations of carbon storage: the estimates of atmospheric carbon locked into the timber of the world’s forests may have been systematically overestimated for at least 50 years.

And another has slightly more cheerful news: assumptions about what trees do at night or in the winter could be wrong. Even at night, vegetation is at work, absorbing nitrogen and building tissues with carbon.

Both studies are tentative. The resulting answers do not make a huge difference to the biggest climate puzzle of all: what happens to the carbon dioxide and other greenhouse gases emitted by the combustion of fossil fuels. This is known as the carbon budget.

But both studies are reminders that when it comes to understanding precisely how the planet’s climate machinery works, there are still many questions to be settled.

“No matter what, plants will not keep up with anthropogenic carbon dioxide emissions; it’s just that they might do better than current models suggest”

French scientists report in the American Journal of Botany that they took a new look at an old formula, the forester’s rule of thumb used for calculating the density of wood in growing trees. And, the scientists say, they have found a small mistake: one big enough, however, to lead to an overestimate of up to 5% in the carbon-storing capacity of an oak, a pine, a eucalypt or a fig.

Scientists at CIRAD, an agricultural research base in Montpellier, France, have kept a database of 1,300 wood species and almost 4,500 trees for the last 70 years. When researchers came to look at a conversion factor in calculations of density, they found something that failed to add up.

“To start with, I thought we had made a mistake in our calculations, or that there was some uncertainty surrounding measurement of the relevant data,” said Ghislain Vieilledent of CIRAD. “It was not easy to cast doubt on a formula that has been widely accepted for years and quoted in several scientific articles.”

It means that estimates of the carbon stored in the world’s forests – a vital component of the carbon budget calculations – could be too high by a relatively small factor. But the global sums are huge.

Uncertainties abound

Human industrial activity releases on average 34 billion tonnes of carbon dioxide each year. Land use is seen as a key factor in mitigating the effects of these emissions. The world’s forests are thought to absorb and store up to 11 billion tonnes of carbon dioxide from the atmosphere each year.

Quite how efficiently this happens depends on a huge range of other factors, including the levels of rainfall and the action of soil microbes and fungi. Nobody knows quite how vegetation will react to higher temperatures, higher ratios of carbon dioxide in the atmosphere, or longer droughts or heatwaves.

There are uncertainties about all these factors: an error in estimating the precise density of wood could be just another sprig of doubt in a forest of confusions.

On the other hand, it could be a straightforward finding that forests are now 5% less good at storing carbon than climate scientists have so far assumed.

Nocturnal activity

But any consequent gloom could be countered by another forest revelation, this time in the journal Nature Climate Change.

Scientists at the Lawrence Berkeley National Laboratory have fashioned a new global land model of the traffic between atmosphere, rocks and living things. They report that plants actually take up more carbon dioxide, and soils surrender less of that other greenhouse gas, nitrous oxide, than previously thought.

And they arrived at this conclusion by taking a closer look at what plants do at night.

The assumption is that they do nothing much at night: there is no photosynthesis, so there is no plant action.

Carbon budget queries

But, the US team says, there is evidence that where nutrients are abundant, plants go on taking up nutrients at night, and even in the non-growing season. In the Arctic, this may account for 20% more nitrogen consumption. In the tropics, it may be as high as 55%.

In which case, the carbon budget estimates could be wrong: the error in the calculation of nitrous oxide released could add up to the equivalent of 2.4 billion tonnes of carbon dioxide not spilled into the atmosphere from the forest floor.

“This is goodish news, with respect to what is currently in climate models,” said William Riley of Lawrence Berkeley Laboratory.

“But it is not good news in general – it’s not going to solve the problem. No matter what, plants will not keep up with anthropogenic carbon dioxide emissions; it’s just that they might do better than current models suggest.” – Climate News Network