Tag Archives: more

Amazon carbon sink declines as trees grow fast, die faster Updated for 2026

Leave a reply




Tropical forests are being exposed to unprecedented environmental change, with huge knock-on effects. In the past decade, the carbon absorbed annually by the Amazon rain forest has declined by almost a third.

At 6 million sq.km, the Amazon forest covers an area 25 times that of the UK, and spans large parts of nine countries. The region contains a fifth of all species on earth, including more than 15,000 types of tree.

Its 300 billion trees store 20% of all the carbon in the Earth’s biomass, and each year they actively cycle 18 billion tonnes of carbon, twice as much as is emitted by all the fossil fuels burnt in the world.

The Amazon Basin is also a hydrological powerhouse. Water vapour from the forest nurtures agriculture to the south, including the biofuel crops which power many of Brazil’s cars and the soybeans which feed increasing numbers of people (and cows) across the planet.

What happens to the Amazon thus matters to the world. As we describe in research published in Nature, the biomass dynamics of apparently intact forests of the Amazon have been changing for decades now with important consequences.

Is climate changing the Amazon?

There are two competing narratives of how tropical forests should be responding to global changes. On one hand, there is the theoretical prospect (and some experimental evidence) that more carbon dioxide will be ‘good’ for plants.

Carbon dioxide is the key chemical ingredient in photosynthesis, so more of it should lead to faster growth and thus more opportunities for trees and whole forests to store carbon. In fact almost all global models of vegetation predict faster growth and, for a time at least, greater carbon storage.

Arrayed against this has been an opposing expectation, based on the physical climate impacts of the very same increase in atmospheric CO2. As the tropics warm further, respiration by plants and soil microbes should increase faster than photosynthesis, meaning more carbon is pumped into the air than is captured in the ‘sink’.

More extreme seasons will also mean more droughts, slowing growth and sometimes even killing trees.

Which process will win?

The work we have led takes a simple approach. With many colleagues, we track the behaviour of individual trees through time across permanent plots distributed right across South America’s rain forests.

Together with hundreds of partners in the RAINFOR network, this close-up look at the Amazon ecosystem has been underway since the 1980s, allowing an unprecedented assessment of how tropical forests have changed over the past three decades.

Our analysis – based on work across 321 plots, 30 years, eight nations, and involving almost 500 people – first of all confirms earlier results. The Amazon forest has acted as a vast sponge for atmospheric carbon. That is, trees have been growing faster than they have been dying.

The difference – the ‘sink’ – has helped to put a modest brake on the rate of climate change by taking up an additional two billion tonnes of carbon dioxide each year.

This extra carbon has been going into ostensibly mature forests, ecosystems which according to classical ecology should be at a dynamic equilibrium and thus close to carbon-neutral.

Amazon trees are finding it harder to survive

However we also found a long and sustained increase in the rate of trees dying in Amazon forests that are undisturbed by direct human impacts.

Tree mortality rates have surged by more than a third since the mid-1980s, while growth rates have stalled over the past decade. This had a significant impact on the Amazon’s capacity to take-up carbon.

Recent droughts and unusually high temperatures in the Amazon are almost certainly behind some of this ‘mortality catch-up’. One major drought in 2005 killed millions of trees. However the data shows tree mortality increases began well before then. Some other, non-climatic mechanism may be killing off Amazonian trees.

The simplest answer is that faster growth, which is consistent with a CO2 stimulation, is now causing trees to also die faster. As the extra carbon feeds through the system, trees not only grow quicker but they also mature earlier. In short, they are living faster, and therefore dying younger.

Thus, 30 years of painstakingly monitoring the Amazon has revealed a complex and changing picture. Predictions of a continuing increase of carbon storage in tropical forests may be overly optimistic – these models simply don’t capture the important feed-through effect of faster growth on mortality.

Forests’ ability to store carbon is reducing

As the Amazon forest growth cycle has been accelerating, carbon is moving through it more rapidly. One consequence of the increase in death should be an increase in the amount of necromass – dead wood – on the forest floor.

While we haven’t measured these changes directly, our model suggests the amount of dead wood in the Amazon has increased by 30% (more than 3 billion tonnes of carbon) since the 1980s. Most of this decaying matter is destined to return to the atmosphere sooner rather than later.

More than a quarter of current emissions are being taken up by the land sink, mostly by forests. But a key element appears to be saturating.

This reminds us that the subsidy from nature is likely to be strictly time-limited, and deeper cuts in emissions will be required to stabilise our climate.

 

 

Published on #IntlForestDay, 21st March 2015.

Oliver Phillips is Professor of Tropical Ecology at the University of Leeds.

Roel Brienen is NERC Research Fellow at the University of Leeds.

This article was originally published on The Conversation. Read the original article.

 

The Conversation

 




391468

Antarctic warmth brings more snow, reducing sea level rise Updated for 2026

Leave a reply




Evidence is mounting that the more the Antarctic warms under the impact of climate change, the more snow will fall on it, causing a build-up of ice.

The research, published in Nature Climate Change, builds on high-quality ice-core data and fundamental laws of physics captured in global and regional climate model simulations.

The team of authors, led by scientists from Germany’s Potsdam Institute for Climate Impact Research (PIK), says each degree Celsius of warming in the region could increase Antarctic snowfall by about 5%.

The suggestion that Antarctic snowfall is increasing is not itself new. But what the Potsdam scientists have done is important: they both provide new evidence to support the contention, and explore its potential consequences.

Katja Frieler, climate impacts and vulnerabilities researcher at PIK, and lead author of the report, says: “Warmer air transports more moisture, and hence produces more precipitation. In cold Antarctica, this takes the form of snowfall.

“We have now pulled a number of various lines of evidence together and find a very consistent result: temperature increase means more snowfall on Antarctica.”

The answers are in the ice-cores

To reach a robust estimate, the PIK scientists collaborated with colleagues in the Netherlands and the US including co-author Peter U. Clark, professor of geology and geophysics at Oregon State University.

“Ice-cores drilled in different parts of Antarctica provide data that can help us understand the future”, he says. “Information about the snowfall spanning the large temperature change during the last deglaciation, 21,000 to 10,000 years ago, tells us what we can expect during the next century.”

The researchers combined the ice-core data with simulations of the Earth’s climate history and comprehensive future projections by different climate models, and were able to pin down temperature and accumulation changes in warming Antarctica.

The ‘good news’ is that the increasing snowfall on the continent will add to the mass of the ice sheet and increase its height, offsetting sea level rise from other causes.

But on balance, Antarctica will still lose ice to the ocean

But the ‘bad news’, say the researchers, is that most of the snow won’t stay there. “Snow piling up on the ice is heavy and presses down – the higher the ice, the more pressure”, co-author Ricarda Winkelmann explains.

On the basis of another previous PIK study, the extra snow will increase the amount of ice flowing to the ocean. “Because additional snowfall elevates the grounded ice-sheet on the Antarctic continent but less so the floating ice shelves at its shore, the ice flows more rapidly into the ocean and contributes to sea level”, says Dr Winkelmann.

So on balance, the sea level-lowering effect from the extra snow is a relatively small one: the 5% increase in Antarctic snowfall that they expect for every 1°C rise in temperature would mean an estimated drop in sea-level of only about three centimetres after a century. By contrast melting ice in Greenland threatens metres of sea level rise.

Adding to Antarctica’s contribution to sea level rise, rising sea levels in the Southern Ocean – mainly caused by the thermal expansion of oceans and melting glaciers around the world, most importantly on Greenland – will allow coastal ice shelves to flow more rapidly into the ocean.

Furthermore even slight warming of the waters lapping Antarctica will make it easier for coastal ice to break off, allowing more of the continental ice mass to discharge into the ocean.

So the frozen continent will still be a net source of sea level rise in a warming world, says co-author Anders Levermann – PIK professor of dynamics of the climate system, and lead author of the sea-level rise chapter in the latest report by Intergovernmental Panel on Climate Change.

“If we look at the big picture, these new findings don’t change the fact that Antarctica will lose more ice than it will gain, and that it will contribute to future sea-level change”, he says.

Dr Frieler agrees: “Under global warming, the Antarctic ice sheet, with its huge volume, could become a major contributor to future sea-level rise, potentially affecting millions of people living in coastal areas.”

 

Alex Kirby writes for Climate News Network.

Oliver Tickell edits The Ecologist.

 




391405

Keystone plankton ‘go slow’ as ocean acidity rises Updated for 2026

Leave a reply




As the planet’s oceans become more acidic, the diatoms – a major group of alga – in the Southern Ocean could grow more slowly.

Nobody expected this. And since tiny, single-celled algae are a primary food source for an entire ocean ecosystem, the discovery seems ominous.

Bioscientist Clara Hoppe and colleagues from the Alfred Wegener Institute at the Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, report in the journal New Phytologist that they tested the growth of the Antarctic diatom Chaetoceros debilis under laboratory conditions.

They used two levels of pH – which is an indicator of acidity – and they exposed their tiny volunteers to constant light and to changing light, providing both standard laboratory conditions and lighting levels that approximated to the real world.

Under variable light in high-CO2 world, plant growth slows

In the unblinking glare of light, the diatoms responded well. Their growth levels were consistent with an assumption that more dissolved carbon dioxide – which makes the waters more acidic – would in effect fertilise plant growth.

Under conditions of changing light, however, it was a different story. The algae grew more slowly, which suggests that the oceans could become less efficient at removing carbon from the atmosphere, and perhaps less valuable as a primary food source for the creatures that teem in the Antarctic waters.

“Diatoms fulfil an important role in the Earth’s climate system”, Dr Hoppe says. “They can absorb large quantities of carbon dioxide, which they bind before ultimately transporting part of it to the depths of the ocean. Once there, the greenhouse gas remains naturally sequestered for centuries.”

Previous research into the steady acidification of the oceans has tended to concentrate on the consequences for coral reefs, fisheries, and tourism, but not on the impact on plant life in the seas.

Since carbon dioxide acts as a fertiliser, higher levels dissolved in the water might stimulate more growth. But growth depends not just on more carbon dioxide, but also on reliable sunlight. In the stormy southern seas, this is not steadily supplied.

Dr Hoppe says: “Several times a day, winds and currents transport diatoms in the Southern Ocean from the uppermost water layer to the layers below, and then back to the surface – which means that, in the course of a day, the diatoms experience alternating phases with more and with less light.”

Her co-author, marine biogeochemist Björn Rost, from the Alfred Wegener Institute, says: “Our findings show for the first time that our old assumptions most likely fall short of the mark. We now know that when the light intensity constantly changes, the effect of ocean acidification reverses.

“All of a sudden, lower pH values don’t increase growth, like studies using constant light show. Instead, they have the opposite effect.”

The implication is that, at certain intensities, the photosynthesis chain breaks down. The point at which light becomes too much light is more quickly reached in waters that are more acidic.

Like all such research, the finding has limitations. It applies to one species of single-celled creature in the waters of one ocean, and the tests were in a laboratory on a small scale, and not in a turbulent ocean rich in life. The Alfred Wegener team will continue their studies.

Fisheries at risk

But in the real world, coastal communities in 15 US states could be at long-term economic risk, as ocean acidification starts to take its toll on the commercial oyster fisheries.

Julia Ekstrom, then of the Natural Resources Defense Council and now director of the Climate Adaptation Programme at the University of California, Davis, and George Waldbusser, assistant professor of ocean ecology and biogeochemistry at Oregon State University report with colleagues, in Nature Climate Change, on an unholy mix in the oceans.

They say that a combination of rising greenhouse gas levels, more acid waters, polluted rivers, and upwelling currents put at risk mollusc fisheries from the Pacific Northwest, New England, the Mid-Atlantic states and the Gulf of Mexico – affecting the shellfish industry that is worth at least $1bn to the US.

Oyster larvae are sensitive to changes in ocean water, and more likely to die as pH levels shift towards the acidic. But acidification is not the only source of stress, as nitrogen-rich nutrients and chemical pollutants cascade from the land into the rivers, and wash through estuaries and fish hatcheries on the coast.

Things can be done. Scientists have been looking at ways in which the industry might be able to adapt to change. But how well the oyster stock can adapt in the long term remains problematic.

“Ocean acidification has already cost the oyster industry in the Pacific Northwest nearly $110 million and has jeopardised about 3,200 jobs”, Dr Ekstrom says.

And Dr Waldbusser adds: “Without curbing carbon emissions, we will eventually run out of tools to address the short term, and we will be stuck with a much longer-term problem.”

 

 

Tim Radford writes for Climate News Network.

 

 




390832

Keystone plankton ‘go slow’ as ocean acidity rises Updated for 2026

Leave a reply




As the planet’s oceans become more acidic, the diatoms – a major group of alga – in the Southern Ocean could grow more slowly.

Nobody expected this. And since tiny, single-celled algae are a primary food source for an entire ocean ecosystem, the discovery seems ominous.

Bioscientist Clara Hoppe and colleagues from the Alfred Wegener Institute at the Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, report in the journal New Phytologist that they tested the growth of the Antarctic diatom Chaetoceros debilis under laboratory conditions.

They used two levels of pH – which is an indicator of acidity – and they exposed their tiny volunteers to constant light and to changing light, providing both standard laboratory conditions and lighting levels that approximated to the real world.

Under variable light in high-CO2 world, plant growth slows

In the unblinking glare of light, the diatoms responded well. Their growth levels were consistent with an assumption that more dissolved carbon dioxide – which makes the waters more acidic – would in effect fertilise plant growth.

Under conditions of changing light, however, it was a different story. The algae grew more slowly, which suggests that the oceans could become less efficient at removing carbon from the atmosphere, and perhaps less valuable as a primary food source for the creatures that teem in the Antarctic waters.

“Diatoms fulfil an important role in the Earth’s climate system”, Dr Hoppe says. “They can absorb large quantities of carbon dioxide, which they bind before ultimately transporting part of it to the depths of the ocean. Once there, the greenhouse gas remains naturally sequestered for centuries.”

Previous research into the steady acidification of the oceans has tended to concentrate on the consequences for coral reefs, fisheries, and tourism, but not on the impact on plant life in the seas.

Since carbon dioxide acts as a fertiliser, higher levels dissolved in the water might stimulate more growth. But growth depends not just on more carbon dioxide, but also on reliable sunlight. In the stormy southern seas, this is not steadily supplied.

Dr Hoppe says: “Several times a day, winds and currents transport diatoms in the Southern Ocean from the uppermost water layer to the layers below, and then back to the surface – which means that, in the course of a day, the diatoms experience alternating phases with more and with less light.”

Her co-author, marine biogeochemist Björn Rost, from the Alfred Wegener Institute, says: “Our findings show for the first time that our old assumptions most likely fall short of the mark. We now know that when the light intensity constantly changes, the effect of ocean acidification reverses.

“All of a sudden, lower pH values don’t increase growth, like studies using constant light show. Instead, they have the opposite effect.”

The implication is that, at certain intensities, the photosynthesis chain breaks down. The point at which light becomes too much light is more quickly reached in waters that are more acidic.

Like all such research, the finding has limitations. It applies to one species of single-celled creature in the waters of one ocean, and the tests were in a laboratory on a small scale, and not in a turbulent ocean rich in life. The Alfred Wegener team will continue their studies.

Fisheries at risk

But in the real world, coastal communities in 15 US states could be at long-term economic risk, as ocean acidification starts to take its toll on the commercial oyster fisheries.

Julia Ekstrom, then of the Natural Resources Defense Council and now director of the Climate Adaptation Programme at the University of California, Davis, and George Waldbusser, assistant professor of ocean ecology and biogeochemistry at Oregon State University report with colleagues, in Nature Climate Change, on an unholy mix in the oceans.

They say that a combination of rising greenhouse gas levels, more acid waters, polluted rivers, and upwelling currents put at risk mollusc fisheries from the Pacific Northwest, New England, the Mid-Atlantic states and the Gulf of Mexico – affecting the shellfish industry that is worth at least $1bn to the US.

Oyster larvae are sensitive to changes in ocean water, and more likely to die as pH levels shift towards the acidic. But acidification is not the only source of stress, as nitrogen-rich nutrients and chemical pollutants cascade from the land into the rivers, and wash through estuaries and fish hatcheries on the coast.

Things can be done. Scientists have been looking at ways in which the industry might be able to adapt to change. But how well the oyster stock can adapt in the long term remains problematic.

“Ocean acidification has already cost the oyster industry in the Pacific Northwest nearly $110 million and has jeopardised about 3,200 jobs”, Dr Ekstrom says.

And Dr Waldbusser adds: “Without curbing carbon emissions, we will eventually run out of tools to address the short term, and we will be stuck with a much longer-term problem.”

 

 

Tim Radford writes for Climate News Network.

 

 




390832

Keystone plankton ‘go slow’ as ocean acidity rises Updated for 2026

Leave a reply




As the planet’s oceans become more acidic, the diatoms – a major group of alga – in the Southern Ocean could grow more slowly.

Nobody expected this. And since tiny, single-celled algae are a primary food source for an entire ocean ecosystem, the discovery seems ominous.

Bioscientist Clara Hoppe and colleagues from the Alfred Wegener Institute at the Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, report in the journal New Phytologist that they tested the growth of the Antarctic diatom Chaetoceros debilis under laboratory conditions.

They used two levels of pH – which is an indicator of acidity – and they exposed their tiny volunteers to constant light and to changing light, providing both standard laboratory conditions and lighting levels that approximated to the real world.

Under variable light in high-CO2 world, plant growth slows

In the unblinking glare of light, the diatoms responded well. Their growth levels were consistent with an assumption that more dissolved carbon dioxide – which makes the waters more acidic – would in effect fertilise plant growth.

Under conditions of changing light, however, it was a different story. The algae grew more slowly, which suggests that the oceans could become less efficient at removing carbon from the atmosphere, and perhaps less valuable as a primary food source for the creatures that teem in the Antarctic waters.

“Diatoms fulfil an important role in the Earth’s climate system”, Dr Hoppe says. “They can absorb large quantities of carbon dioxide, which they bind before ultimately transporting part of it to the depths of the ocean. Once there, the greenhouse gas remains naturally sequestered for centuries.”

Previous research into the steady acidification of the oceans has tended to concentrate on the consequences for coral reefs, fisheries, and tourism, but not on the impact on plant life in the seas.

Since carbon dioxide acts as a fertiliser, higher levels dissolved in the water might stimulate more growth. But growth depends not just on more carbon dioxide, but also on reliable sunlight. In the stormy southern seas, this is not steadily supplied.

Dr Hoppe says: “Several times a day, winds and currents transport diatoms in the Southern Ocean from the uppermost water layer to the layers below, and then back to the surface – which means that, in the course of a day, the diatoms experience alternating phases with more and with less light.”

Her co-author, marine biogeochemist Björn Rost, from the Alfred Wegener Institute, says: “Our findings show for the first time that our old assumptions most likely fall short of the mark. We now know that when the light intensity constantly changes, the effect of ocean acidification reverses.

“All of a sudden, lower pH values don’t increase growth, like studies using constant light show. Instead, they have the opposite effect.”

The implication is that, at certain intensities, the photosynthesis chain breaks down. The point at which light becomes too much light is more quickly reached in waters that are more acidic.

Like all such research, the finding has limitations. It applies to one species of single-celled creature in the waters of one ocean, and the tests were in a laboratory on a small scale, and not in a turbulent ocean rich in life. The Alfred Wegener team will continue their studies.

Fisheries at risk

But in the real world, coastal communities in 15 US states could be at long-term economic risk, as ocean acidification starts to take its toll on the commercial oyster fisheries.

Julia Ekstrom, then of the Natural Resources Defense Council and now director of the Climate Adaptation Programme at the University of California, Davis, and George Waldbusser, assistant professor of ocean ecology and biogeochemistry at Oregon State University report with colleagues, in Nature Climate Change, on an unholy mix in the oceans.

They say that a combination of rising greenhouse gas levels, more acid waters, polluted rivers, and upwelling currents put at risk mollusc fisheries from the Pacific Northwest, New England, the Mid-Atlantic states and the Gulf of Mexico – affecting the shellfish industry that is worth at least $1bn to the US.

Oyster larvae are sensitive to changes in ocean water, and more likely to die as pH levels shift towards the acidic. But acidification is not the only source of stress, as nitrogen-rich nutrients and chemical pollutants cascade from the land into the rivers, and wash through estuaries and fish hatcheries on the coast.

Things can be done. Scientists have been looking at ways in which the industry might be able to adapt to change. But how well the oyster stock can adapt in the long term remains problematic.

“Ocean acidification has already cost the oyster industry in the Pacific Northwest nearly $110 million and has jeopardised about 3,200 jobs”, Dr Ekstrom says.

And Dr Waldbusser adds: “Without curbing carbon emissions, we will eventually run out of tools to address the short term, and we will be stuck with a much longer-term problem.”

 

 

Tim Radford writes for Climate News Network.

 

 




390832

Keystone plankton ‘go slow’ as ocean acidity rises Updated for 2026

Leave a reply




As the planet’s oceans become more acidic, the diatoms – a major group of alga – in the Southern Ocean could grow more slowly.

Nobody expected this. And since tiny, single-celled algae are a primary food source for an entire ocean ecosystem, the discovery seems ominous.

Bioscientist Clara Hoppe and colleagues from the Alfred Wegener Institute at the Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, report in the journal New Phytologist that they tested the growth of the Antarctic diatom Chaetoceros debilis under laboratory conditions.

They used two levels of pH – which is an indicator of acidity – and they exposed their tiny volunteers to constant light and to changing light, providing both standard laboratory conditions and lighting levels that approximated to the real world.

Under variable light in high-CO2 world, plant growth slows

In the unblinking glare of light, the diatoms responded well. Their growth levels were consistent with an assumption that more dissolved carbon dioxide – which makes the waters more acidic – would in effect fertilise plant growth.

Under conditions of changing light, however, it was a different story. The algae grew more slowly, which suggests that the oceans could become less efficient at removing carbon from the atmosphere, and perhaps less valuable as a primary food source for the creatures that teem in the Antarctic waters.

“Diatoms fulfil an important role in the Earth’s climate system”, Dr Hoppe says. “They can absorb large quantities of carbon dioxide, which they bind before ultimately transporting part of it to the depths of the ocean. Once there, the greenhouse gas remains naturally sequestered for centuries.”

Previous research into the steady acidification of the oceans has tended to concentrate on the consequences for coral reefs, fisheries, and tourism, but not on the impact on plant life in the seas.

Since carbon dioxide acts as a fertiliser, higher levels dissolved in the water might stimulate more growth. But growth depends not just on more carbon dioxide, but also on reliable sunlight. In the stormy southern seas, this is not steadily supplied.

Dr Hoppe says: “Several times a day, winds and currents transport diatoms in the Southern Ocean from the uppermost water layer to the layers below, and then back to the surface – which means that, in the course of a day, the diatoms experience alternating phases with more and with less light.”

Her co-author, marine biogeochemist Björn Rost, from the Alfred Wegener Institute, says: “Our findings show for the first time that our old assumptions most likely fall short of the mark. We now know that when the light intensity constantly changes, the effect of ocean acidification reverses.

“All of a sudden, lower pH values don’t increase growth, like studies using constant light show. Instead, they have the opposite effect.”

The implication is that, at certain intensities, the photosynthesis chain breaks down. The point at which light becomes too much light is more quickly reached in waters that are more acidic.

Like all such research, the finding has limitations. It applies to one species of single-celled creature in the waters of one ocean, and the tests were in a laboratory on a small scale, and not in a turbulent ocean rich in life. The Alfred Wegener team will continue their studies.

Fisheries at risk

But in the real world, coastal communities in 15 US states could be at long-term economic risk, as ocean acidification starts to take its toll on the commercial oyster fisheries.

Julia Ekstrom, then of the Natural Resources Defense Council and now director of the Climate Adaptation Programme at the University of California, Davis, and George Waldbusser, assistant professor of ocean ecology and biogeochemistry at Oregon State University report with colleagues, in Nature Climate Change, on an unholy mix in the oceans.

They say that a combination of rising greenhouse gas levels, more acid waters, polluted rivers, and upwelling currents put at risk mollusc fisheries from the Pacific Northwest, New England, the Mid-Atlantic states and the Gulf of Mexico – affecting the shellfish industry that is worth at least $1bn to the US.

Oyster larvae are sensitive to changes in ocean water, and more likely to die as pH levels shift towards the acidic. But acidification is not the only source of stress, as nitrogen-rich nutrients and chemical pollutants cascade from the land into the rivers, and wash through estuaries and fish hatcheries on the coast.

Things can be done. Scientists have been looking at ways in which the industry might be able to adapt to change. But how well the oyster stock can adapt in the long term remains problematic.

“Ocean acidification has already cost the oyster industry in the Pacific Northwest nearly $110 million and has jeopardised about 3,200 jobs”, Dr Ekstrom says.

And Dr Waldbusser adds: “Without curbing carbon emissions, we will eventually run out of tools to address the short term, and we will be stuck with a much longer-term problem.”

 

 

Tim Radford writes for Climate News Network.

 

 




390832

Straw homes are a cheap and green fix for the housing crisis Updated for 2026

Leave a reply




The UK construction sector must reduce its energy consumption by 50% and its carbon emissions by 80% by 2050.

So radical changes are needed to the way we approach building houses. Straw could be a critical part of the transition towards a low-carbon future.

The thermal insulation value of a typical straw bale wall meets the requirements of even the most demanding performance specifications.

Recent research led by the BRE Centre for Innovative Construction Materials at the University of Bath has shown that straw bale buildings reduce energy bills by 90% compared to conventional housing stock.

The manufacture of cement, used in concrete, is responsible alone for up to 8% of all industrially produced greenhouse gas emissions. Using natural materials such as straw, often directly from the field and with little further processing, significantly reduces this impact.

Traditionally, the environmental impact of construction materials has been significantly less than the impact of occupation (heating, cooling and so on) over the lifespan of the building. However, in modern energy efficient buildings the proportion attributable to that ’embodied’ in the fabric of the building is expected to increase to at least 90%.

Measures to reduce the impact of the embodied energy and carbon will deliver even more environmentally friendly buildings.

A natural building material

Straw is just the dried stalks of plants stripped of their grain. You don’t really ‘make straw’ – it’s a co-product of grain production, an established and essential agricultural process. So using straw doesn’t displace land required for essential food production.

In the UK more than 7m tonnes of straw remains after the production of wheat, and up to half this amount is effectively discarded due to its low value – simply chopped up and returned to the soil.

As an average three-bedroom house needs 7.2 tonnes of straw, the ‘leftover’ could be used to build more than 500,000 new homes – a city the size of Birmingham could be built each year using discarded straw.

Straw is also a low-cost material. But more importantly, as a plant it captures and stores atmospheric carbon dioxide during photosynthesis. By using more and more straw in buildings we are creating a natural carbon storage bank.

Though the bible references using straw for bricks – and thatched roofs – have been common for centuries, modern straw construction was developed when mechanical baling machines were first used in late 19th-century Nebraska.

Stacked like large bricks, straw bales can be used for modest loadbearing as well as non-loadbearing walls. The oldest surviving straw bale building is around 100 years old.

But straw has never caught on as an alternative to bricks, concrete or timber. There are concerns about its poor durability, fire resistance, the way it attracts mice and rats and, as one of the three little pigs found out the hard way, its lack of structural integrity.

The answer – high precision pre-fabricated ‘bales’

Straw bales aren’t currently made to the same levels of tolerance and specification as bricks or cement. The fact they’re generally slightly different sizes combined with the need to keep bales dry during construction has meant most builders would not, until recently, consider straw bales a viable solution for anything. Other than perhaps for enthusiastic self-builders.

However, the development of prefabricated wall panels using straw bale for insulation has now provided the opportunity to market straw to the mainstream construction industry.

Prefabrication, or off-site manufacture, means that wall panels can be made to a very high specification in a factory, protected from variable weather conditions that would otherwise inhibit on-site building with straw.

A prefabricated product can be certified as fit for use by industry bodies, making it much more acceptable to builders, financiers and insurers. It also radically reduces site construction times, with houses able to be erected in ten weeks instead of around 16 weeks for more conventional buildings. It seems the time has arrived for straw bale construction.

For the past ten years the University of Bath has been working with a local company, ModCell, to develop prefabricated straw bales. We started out looking at straw as a low-carbon cladding solution and soon moved on to developing panels that could bear heavy loads. Now, we are able to make low-energy prefabricated straw bale houses.

 

Bath’s own straw house. The panels from 00:09 onwards are all prefab straw and lime plaster.

Officially approved for the formal construction sector

The panels have been subjected to fire tests, thermal transmittance tests, accelerated weathering tests, acoustic tests, simulated flooding and impact testing. We’ve even tested the structures in a simulated hurricane force wind, in what has been termed the ‘big bad wolf’ test: the panels and prototype BaleHaus passed with flying colours.

These panels have now been granted certification. This in turn means insurers will cover straw houses and home-buyers will be able to obtain mortgages.

Hayesfield School in Bath, EcoDepot in York and the School of Architecture at the University of the West of England have all made use of these panels. Certification means the housing market can now use straw too, with LILAC in Leeds completed in 2013 and now a new development in Bristol due for completion later this year, with proposals for larger schemes already in planning.

Modern prefabricated straw bale houses are affordable, deliver excellent levels of energy efficiency in use for the home-owner or occupier and provide a genuine sustainable solution by using a cheap and widely available agricultural co-product.

Other similar prefabricated systems using straw bale construction have been developed in Australia, Belgium and Canada. Entire communities, towns or even cities built from straw bales. And why not?

 

 

Pete Walker is Director, BRE Centre for Innovative Construction Materials at the University of Bath.

This article was originally published on The Conversation. Read the original article.

The Conversation

 




390068

Election 2015: finally, our chance to ditch Trident Updated for 2026

Leave a reply




Trident has in the last few weeks become one of the most potent symbolic political markers for the forthcoming election, and is likely to feature heavily in the debates.

Some of us who have been closely involved in the issue for decades may have been taken by surprise … previous promising moments have come and gone with minimal fuss and it has been a challenge not to become cynical.

But this time is different, and there are a number of factors at play, not least the rise of the smaller parties.

Whilst they lost the referendum back in September, the SNP were closer than most were expecting a year ago to successfully breaking up the union. Since then they have experienced a surge of support, are likely to increase their representation in Westminster in May and could well be a crucial dimension in any power arrangement after the election.

They have already highlighted the removal of Trident bases from Scotland as an absolute condition of any support they may give in negotiations. Statements have been uncompromising, so that it will be a big political challenge to row back from them should they come under pressure to change course.

A strong Green challenge could prove decisive

The Green Party, previously hoping to secure 2-3 seats on a very good day, could become serious challengers for more. Perhaps equally importantly, Green candidates up and down the country could capture many left-wing votes from disillusioned left wing voters who see the cautious positioning of Labour with dismay.

Some have even been suggesting that the Greens could do more damage to Labour prospects than the threat UKIP has to the Tories, in a sort of Ralph Nader moment.

They already have more members than UKIP and the LibDems, and could break through 50,000 in the coming few weeks. Of course, it is moments like these, with the Greens punishing the larger parties for their reckless support of unsustainable neo-liberal capitalist solutions, that their influence is strongest.

So far, particularly on the Trident issue, Labour has been captured by the narrative around legacies of lost elections in the dim and distant past. But their paranoia about being seen as a left wing could yet cost them more votes than it secures. It is about time they realized that the public is in a very different place.

When in the 1980s, heavily influenced by the fear-induced Cold War, a strong unilateralist stance may well have lost crucial support in various parts of the country, it is today generally ambivalent towards investment on Trident.

A time of austerity and cuts just when a new generation of submarines demands major investment could yet prove fatal to the project.

Is this a clever way for the UK to spend £4 billion a year?

Much has been made by campaign groups of the £100bn lifetime cost of the system, which is a reasonable estimate given the uncertainties involved in financial forecasting over such a long period.

Perhaps more meaningful, though, is the annual spend … and this will soon be shooting up from around £2.5bn today towards £4bn a year throughout the 2020s, with capital costs consuming a full one third of the whole defence procurement budget across the decade.

In Tuesday’s Commons debate former Lib Dem defence minister Nick Harvey used parliamentary privilege to expose the fact that the army is being asked to come up with plans to make do with manpower levels around 60,000 – a massive cut and one likely to reverberate around the Shires.

This creates unusual allies between anti-nuclear activists and armed forces constituencies.

Cheaper dual-capable nuclear options to Trident that could also plug the armed forces financial gap are now being considered seriously, promising to split the pro-deterrence lobby, enabling some to join the clamour for a reassessment and a less distorted government review later in 2015.

Cold war warmed up?

But remember: Trident is a weapon system dreamt up and developed in a Cold War context. Skirmishes and threats at the margins of Europe aside, no-one seriously considers the prospects of Britain facing an aggressive and totalitarian nuclear superpower alone as significant.

And yet that is the only scenario that could just justify the independent nuclear deterrent that both the Tory-led government and Labour Party are currently committed to hollowing out the armed forces for.

At a time when the future of the Nuclear Non-Proliferation Treaty (NPT) hangs in the balance and states parties meet in New York for their every-five year review (at the same time as the election), Britain’s leadership is critical. And yet we are nowhere, our credibility severely dented by this insistence on wasting billions on our own arsenal.

Nuclear weapon states meet in London in early February to consider their game plan at the conference. The hopes of them pulling any scrawny rabbits out the hat at this final hour seem dim indeed.

Your vote can help rid us of this terrorist monstrosity

Returning to the election, the best we can realistically hope for from Labour is that it retain its commitment to a minimum credible nuclear deterrent – with some ambiguity around the posture and systems this entails, on the basis that Trident must be included in the Defence and Security Review soon after the election.

This will enable smaller parties, notably the SNP and the Greens, to take on a critical role in post election talks and demand a change in policy on Trident.

But what they do before the election matters too: the more they raise Trident in the campaign, the more they reflect public opposition to the spend, and the more influential they are in the result, the stronger their elbow at this crucial point becomes.

Perhaps then we will see a new government pause, order another delay and review, and perhaps we may yet see them move back from committing to a new generation of nuclear weapons before it’s too late and the money is committed.

Voters in Britain have a bigger chance than they have ever before to bring an end to Britain’s addiction to nuclear weapons, and cause an important upset to the global nuclear order.

 

 

Demo: Wrap up Trident – today, midday at the MOD in London.

Paul Ingram has been the Executive Director for the British American Security Information Council (BASIC) since 2007. BASIC works in the US, UK, Europe and the Middle East to promote global nuclear disarmament and a transformation in strategic relationships using a dialogue approach.

He was also until recently a talk show host on state Iranian TV promoting alternative perspectives on strategic matters, and taught British senior civil servants leadership skills.

Previously Paul was a Green Party councillor in Oxford and co-Leader of Oxford City Council (2000-2002) and a member of the Stop the War Coalition Steering Group (2002-2006).

 

 




389402

Inequality does matter – and we must fight it! Updated for 2026

Leave a reply




Since the 1980s, we’ve been told that inequality doesn’t matter. Mainstream thinking has it that you can fight poverty without tackling inequality.

This has been part of an attempt to make poverty eradication easier and more palatable to an increasingly dominant right-wing agenda.

The beauty of separating poverty and inequality is that you can care about ‘the poor’ while not worrying about the need for any of the radical changes which might upset your lifestyle.

You can both be “intensely relaxed about people getting filthy rich”, as Peter Mandelson1 said, and also care about very poor people getting less poor.

This embracing of inequality has, unsurprisingly, gone hand-in-hand with soaring levels of it. Today the richest 80 people own almost as much wealth as half the world’s population.

The situation continues to get worse. While most ordinary people endure pay freezes and austerity, the world’s richest 300 people became richer by 16% in 2013.

Those who are unhappy with inequality are accused of pursuing the ‘politics of envy’, or as Margaret Thatcher once put it, of preferring that the poor were poorer provided the rich were less rich. There are two big problems with this argument.

Inequality matters

The first is that inequality does matter. This is not a matter of serious debate. Even the International Monetary Fund (IMF), hardly a progressive voice, has issued a warning that rising inequality is threatening economic growth.

This is firstly because rich people are far more likely to spend money in ways that do not benefit the majority of people, such as on luxury imported goods or simply stashing it away in an account in the Cayman Islands. The idea that if you get enough tycoons buying yachts, the jobs created by the yacht building industry will be enough to feed everyone else is a fiction.

Second, inequality warps democracy. It raises the voices and interests of tiny elites above the rest of society. This can lead to perverse results and greater corruption, with laws and policies tailored to the personal interests of tycoons and to the detriment of wider society.

It’s not just the economy that is affected by inequality. Most of the attributes of a decent society – health, education, crime levels, social cohesion – are most present in more equal societies.

Take the USA and Sweden, two countries with similar levels of wealth in GDP per capita terms. The infant mortality rate in the USA is more than double that of Sweden and the murder rate is over three times Sweden’s figure.

This pattern holds up across the world. The charts (see report) show that, in general, countries with high levels of inequality have higher murder rates and lower life expectancy.

The poor are not getting richer

So it’s no wonder that we find that since the big surge in free market, neoliberal economic policies in the 1980s, while the rich have certainly got richer, the poor have, by and large, stayed poor.

Back in 1981, when the free market revolution was just taking off, there were 288 million people in sub-Saharan Africa living on less than $2 a day (205 million were living on under $1.25 a day). By 2008, this figure had almost doubled to 562 million (386 million on under $1.25 a day).

Of course the region’s population has also increased over this period, but even proportionally, there has been almost no improvement in poverty rates in sub-Saharan Africa since 1981.

Other continents have done a little better but mostly because of the arbitrary measures chosen. Why $1.25? Much anti-poverty work has been geared to getting people from just below, to just above the international poverty line. It has been claimed that if you changed the poverty line from $1.25 to $1.27, most recent poverty reduction gains would be wiped out.

In fact the vast majority of the fall in global poverty since 1981 has come from China, a country that, despite engaging its very own state-led, form of capitalism, has not followed World Bank-led free market policies.

Here in the UK, real wages have fallen since the economic crisis in 2008. But in those same terms, wages hardly rose in the boom years of the 1990s and 2000s either. Almost all of the proceeds of this boom went to a tiny elite. The big winners from this decline in income have been the credit card companies.

Consumer debt has tripled over the last two decades as people borrow in order to make ends meet, reaching £158 billion in 2013. Meanwhile, the proportion of UK income controlled by the top 1% of the population has doubled since 1970 and the top 1% own as much as the bottom 55%.

The corrosive injustice of inequality

Inequality isn’t good for getting people out of poverty, which shouldn’t be surprising. Poverty isn’t about having a certain amount of money, but the lack of those resources we all need for a decent life; food and water, housing and energy, healthcare, education and decent employment.

Poverty is lack of power. And that lack of power is a direct consequence of others having too much power – ultimately too much control over resources. Wealth comes from exploitation of people and the planet’s resources.

This is why even well-intentioned plans to make the poor richer are doomed to failure if they ignore the question of power.

Helping the poor to buy more products or rent more resources from the rich might provide short-term relief, but in the long-term will reinforce the unequal relationship between the two – just as 19th-century American slave owners who decided to treat their slaves better missed the real injustice that they were perpetrating.

The poor will only get richer by radically reducing inequality, which in turn requires confronting power.

 

 

This article is an extract from the report ‘The poor are getting richer and other dangerous delusions‘ by Global Justice Now (formerly the World Development Movement).

 




389192

Travelling around to catch more parasites? Updated for 2026

Leave a reply

Do migratory birds catch more parasites? This is explored in the Oikos Early View paper “Flying with diverse passengers: greater richness of parasitic nematodes in migratory birds” by Janet Koprivnikar and tommy L.F. Leung. Below is their short summary of the study:

Many different animals undergo annual migrations and some of them cover enormous distances with their journey. This undertaking can be extremely strenuous and physiologically demanding. Aside from the demands of the journey itself, most animals don’t travel alone – they carry with them an entire community of different parasites throughout their body. Migratory birds undergo annual migratory flights across the globe and birds are well known to be a haven for
pathogens. Most birds are infected with dozens of different species of parasite, many of them worms of all shapes and sizes. While most studies looking at bird parasites in relation to their ecology or migratory habits have focused on blood-dwelling types such as avian malaria, few have studied their worms despite the relative abundance of these parasites in their hosts. Of those different types of worms, the most harmful are the nematodes (roundworms). Some nematodes can cause serious diseases in birds so we decided to compare the diversity of parasitic roundworms in migratory birds versus that of non-migratory species.

In particular, we focused our attention on three orders of birds; water birds (Anseriformes), perching birds (Passeriformes), and birds of prey (Accipitriformes). We found that for any of those given orders, the migratory species tended to have a wider range of roundworms than non-migratory species. Furthermore, we also found that bird species which have proportionally larger spleens also happen to have a greater variety of roundworms infecting them.

So why do migratory species have more diverse nematode communities than their non-migratory relatives? We don’t know that at this point. It is possible that migratory birds pick up many different species of parasites during their journey whereas non-migratory species which stick to a single location their entire life are exposed to a more limited range of parasites. Or perhaps because migration is such a stressful exercise, migratory birds can become stressed during such journeys and become more vulnerable to a wider variety of parasites. Or it might be both!
Due to the diseases that parasitic roundworms can cause in birds, it is important to also keep them in mind when considering the effects that global perturbations such as climate change can have on the ecology of migratory species. As migratory birds change their arrival and departure timing, and are also forced to alter their migratory routes and stopover sites, they might become more stressed and susceptible to parasitism. Furthermore, altered migratory routes and stopover sites can also mean that migratory birds might be introducing their rich suite of worms to new areas and potential hosts.

About these ads