Earth at risk in new epoch ruled by destructive humans

Earth at risk in new epoch ruled by destructive humans

Scientists warn that our fate is in our own hands as humans now control almost every aspect of the planet, on a scale akin to the great forces of nature.

LONDON, 21 March, 2015 − Nature has been replaced by humans as the driving force behind changes on the planet − and we need to take urgent action if we are to avoid our own destruction.

This is the view of two scientists – including a Nobel prize winner − who support the theory that the planet has entered a new Anthropocene epoch that has succeeded the Holoscene, the  current geological warm period that began at the end of the ice age 11,500 years ago.

It is not a new concept − the name Anthropocene was coined 15 years ago by American ecologist Eugene F. Stoermer to describe how humans had taken over from nature to decide the planet’s future − but the authors of a new paper believe they have shown that it is now a frightening reality.

Paul Cruzten, the 1995 Nobel Laureate in Chemistry, from the Max Planck Institute for Chemistry, in Mainz, Germany, and Stanislaw Waclawek, researcher in the Department of Nanomaterials in Natural Sciences at the Technical University of Liberec, Czech Republic, make their case in the paper published in the new Chemistry-Didactics-Ecology-Metrology.

Human footprint

The article claims that the negative impact of the human footprint ensures a gradual destruction of the Earth, “Our survival fully depends on us,” Cruzten says.

The scientists claim that there is overwhelming evidence that what they term “man, the eroder” now transforms all Earth system processes. They offer this list in support of their argument:

  • Excessively rapid climate change, so that ecosystems cannot adapt.
  • The Arctic ocean ice cover is thinner by approximately 40% than it was 20-40 years ago.
  • Ice loss on land is causing the rising sea levels.
  • Overpopulation (a fourfold increase in the 20th century alone).
  • Increasing demand for freshwater.
  • Releases of nitrogen oxide into the atmosphere, resulting in high surface ozone layers.
  • Loss of agricultural soil through erosion.
  • Loss of phosphorous (dangerous depletion in agricultural regions).
  • Melting supplies of phosphate reserves (leading to serious reduction in crop yield).

The paper begins: “Humankind actions are exerting increasing effect on the environment on all scales, in a lot of ways overcoming natural processes.

“During the last 100 years, human population went up from little more than one billion to six billion, and economic activity increased nearly 10 times between 1950 and the present time.”

Industrial activity

In a series of graphics, the two scientists show how the growth of population, industrial activity and, above all, the release of greenhouse gases are causing chaos in nature and threatening our existence.

The paper says: “Taking into account these and many other major and still growing footprints of human activities on Earth and atmosphere, without any doubt we can conclude that we are living in new geological epoch named the Anthropocene.”

Cruzten warns: “This ensures a gradual destruction of the Earth. For the sake of our children and grandchildren, we must change course.” – Climate News Network

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Powerful wind blows through US energy sector

Powerful wind blows through US energy sector

Wind power in the US now generates enough electricity for more than 11 million homes, but it needs government support for further growth.

LONDON, 20 March, 2015 − The wind turbines are turning across America, and a major report by the US Department of Energy (DOE) says the wind energy sector now supplies 4.5% of the nation’s electricity.

Given the right energy policies and investment in infrastructure, that figure could increase to 10% by 2020 and to 35% by 2050, the DOE predicts.

That will not only benefit tens of thousands of workers who will be employed in one of the US’s fastest-growing industries. It’s also good news for the climate, and will help preserve increasingly precious water supplies.

“Deployment of wind technology for US electricity generation provides a domestic, sustainable and essentially zero carbon, zero pollution and zero water-use US electricity resource,” the DOE says.

Impressive growth

The rate of growth of wind power in the US has been impressive. In 2011 alone, nearly 3,500 turbines went up across the country. And the Natural Resources Defence Council says that a typical 250 megawatt wind farm − around 100 turbines − will create 1,073 jobs over the lifetime of the project.

The DOE says costs of wind power are dropping, while reliability and other issues are being sorted out. “Wind generation variability has a minimal and manageable impact on grid reliability and costs,” the report says.

Texas is the top wind power state, followed by Iowa, California and Oklahoma. At the end of 2013, the US had 61 gigawatts (GW) installed − up from 25 GW in 2009.

The aim is to increase those figures to 113 GW by 2020, to 224 GW by 2030, and to more than 400 GW by 2050.

The DOE says that if these plans are realised, the emission into the atmosphere of more than 12 gigatonnes of climate changing greenhouse gases (GHG) will be avoided.

“Pairing this homegrown resource with continued technology innovation has made the US the home of the most productive wind turbines in the world”

“Wind deployment can provide US jobs, US manufacturing and lease and tax revenues in local communities to strengthen and support a transition towards a low-carbon US economy,” the report says.

The trouble is that there is considerable resistance to wind power in parts of the political establishment. The DOE report – while not directly accusing Washington of standing in the way of progress on wind − does say that “new tools, priorities and emphases” need to be set in place in order to achieve wind energy targets.

These include an urgent need for a large-scale infrastructure programme in order to build wind power transmission lines.

The American Wind Energy Association, (AWEA), body that represents the industry, calculates that about 900 miles of transmission lines need to be put in place each year up to 2050 if the DOE is to achieve its wind power goals.

Tax policies to encourage wind development are also required. A special Wind Production Tax Credit (PTC), which effectively gave subsidies to the wind industry of about $13 billion a year, was brought in 1992.

Receive subsidies

But when the tax credit came up for renewal in 2012, it was not retained in the tax code, and finally lapsed at the end of 2013, although the oil, gas, fracking and coal industries – all major GHG emitters − have continued to receive subsidies.

Political analysts say there is little likelihood that the PTC will be renewed by a legislature controlled by the Republican party – which is generally opposed to giving financial incentives to the renewable energy sector.

The elimination of tax breaks initially slowed growth in the construction of wind energy facilities, but the industry remains upbeat and says investors are still putting money into projects.

“The US is blessed with an abundant supply of wind energy,” the AWEA says. “Pairing this homegrown resource with continued technology innovation has made the US the home of the most productive wind turbines in the world.” – Climate News Network

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Growing threat to Amazon’s crucial carbon sink

Growing threat to Amazon’s crucial carbon sink

Massive new study shows that pressures on the Amazon rainforest mean it can no longer be relied on to soak up more CO2 from the atmosphere than it puts out.

LONDON, 19 March, 2015 − The Amazon rainforest, for so long one of the vital “green lungs” of the planet, is losing its capacity to absorb carbon from the atmosphere, according to new research.

Two decades ago, the forest drew down a peak of two billion tonnes of carbon dioxide each year from the atmosphere. Now, according to a massive new study in Nature journal by more than 90 scientists, the rate of withdrawal has fallen to around half that total.

Fossil fuel emissions from Latin American countries are now running at more than a billion tonnes of CO2. So the region is putting more greenhouse gas into the atmosphere than it is taking out.

The finding is ominous. The Amazon rainforest has always been a big item in the climate modellers’ carbon budget − the calculation of carbon dioxide from fossil fuels burned, set against the natural absorption of the same trace gases by the biosphere.

Unique research

The implication now is that the forest is no longer a carbon “sink” that that can be relied upon to take up a predictable proportion of fossil fuel emissions.

The conclusion is the outcome of a unique international research network’s 30-year study of 189,000 individual trees in 321 plots of forest dotted across six million square kilometres in eight South American countries. And it has revealed a huge surge in the rate of tree deaths across the Amazon basin.

Locations of Amazon forest plots studied. Image: Georgia Pickavance/RAINFOR

Locations of Amazon forest plots studied.
Image: Georgia Pickavance/RAINFOR

The Amazon is one of the wonders of the planet: its 300 billion trees, and 15,000 species, store one-fifth of all the carbon in the planet’s biomass.

The RAINFOR collaboration involves 57 organisations in 15 nations, and is dedicated to detailed study of the forest and the ecosystems that depend upon it.

“Tree mortality rates have increased by more than a third since the mid-1980s, and this is affecting the Amazon’s capacity to store carbon”

Researchers have repeatedly warned of the consequences of destroying rainforest through logging, land-clearance for plantation,  and other assaults upon the gigantic rainforest, but this finding is of a different magnitude altogether.

Roel Brienen, a geographer at the University of Leeds in England, and the lead author of the study, puts it bluntly: “Tree mortality rates have increased by more than a third since the mid-1980s, and this is affecting the Amazon’s capacity to store carbon.”

Carbon dioxide is not, of itself, the problem. Plants capture it with photosynthesis to build tissues and feed the animal kingdom. And, in a greenhouse world, more carbon dioxide should make vegetation more fertile, and more likely to soak up at least a proportion of the extra carbon dioxide from car exhausts and power station chimneys.

Spurt of growth

But the message from this latest study is that it doesn’t necessarily work out like that. The extra carbon dioxide stimulated a spurt of extra growth, and the trees lived faster, only to die sooner.

The problem has been compounded by drought and unusually high temperatures in the Amazon. The spurt in arboreal death rates began well before 2005, but droughts since then have killed millions of additional trees.

“Regardless of the causes behind the increase in tree mortality, this study shows that predictions of a continuing increase of carbon storage in tropical forests may be too optimistic,” Dr Brienen says.

“Climate change models that include vegetation responses assume that as long as carbon dioxide levels keep increasing, then the Amazon will continue to accumulate carbon. Our study shows that this may not be the case, and that tree mortality processes are critical in this system.” – Climate News Network

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Heat is on to slow down faster rise in temperatures

Heat is on to slow down faster rise in temperatures

New research warns that emissions will make drought conditions even more extreme as our climate moves into a period of rapid change.

LONDON, 12 March, 2015 – Analysis of temperature records and reconstructions of past climates indicates that the pace of global warming is about to accelerate.

Although the much-debated “pause” in warming during the 21st century is still under debate, climate scientist now warn that the Earth is about to enter a period of change that will be faster than anything in the last thousand years.

Steven Smith, an integrated modelling and energy
scientist, at the US government’s Pacific Northwest National Laboratory, and colleagues decided to take a look at the short history of temperature records and the somewhat longer “proxy” reconstructions of past climates to look for patterns of the past that might be a guide to the future.

Baseline rates

They then matched the past and examined the future using computer model simulations. Climate periods were considered in 40 year blocks, and were compared to establish a baseline for natural rates of change.

The scientists report in Nature Climate Change that rises now in North America and many parts of the world are greater than the natural range for any rate of change.

And when they tested future emissions scenarios, they confirmed that global warming will pick up speed in the next 40 years in all cases − even in those projections in which the world reduced its greenhouse gas emissions. And if the world doesn’t reduce these emissions, the rate of change in warming will remain high for the rest of the century.

“In these climate model simulations, the world is just now starting to enter a new place, where rates of temperature change are consistently larger than historical values over 40-year time spans,” Dr Smith says. “We need to better understand what the effects of this will be, and how to prepare for them.”

The research is based on simulation, and seems inconsistent with the story of the 21st century, which is that, after a relatively rapid decadal rise in global average temperatures between 1970 and 2000, the rate of rise seemed to slow.

Although almost all the years of the new century so far have been warmer than any in the 20th century, and although 2014 was the warmest year on record so far, the notches on the thermometer each year have been smaller.

But as researchers have repeatedly warned, the real rise may be masked by some kind of natural variation. At least one group in 2014 found that the patterns of extremes of heat seem to be accelerating, even if the averages are not.

“The finding is critical to understanding
what the world will be like
as the climate continues to change”

And now Rong Fu, professor of geological sciences at the University of Texas at Austin, US, has looked at a study by research scientists William Lau, of the University of Maryland, and Kyu-Myong Kim, of the NASA Goddard Space Flight Centre, and seen signs of an intensified pattern of extreme droughts in Australia, the southwest and central US, and southern Amazonia.

The Proceedings of the National Academy of Sciences has published both the original research and the commentary  by Professor Fu.

At the heart of the issue is the impact of increased emissions of carbon dioxide on the pattern of wind circulation that overall dictates the climate of each hemisphere.

This pattern is sometimes called the Hadley Circulation, named after the 18th-century English lawyer and amateur meteorologist, George Hadley, who first identified the mechanism behind the all-important Trade Winds that carried sailing ships across the Atlantic.

It can change with global temperatures. And as the winds change – and the prevailing Trade Winds move away from the tropics – they take the rainfall with them.

Ominous consequences

The guess has been that Hadley Circulation varies naturally. And the PNAS study suggests that it is likely to intensify in a warmer world, with ominous consequences for some already naturally dry regions.

That both Australia and the American southwest are already feeling the heat is not news. But the significance of the research lies in more detailed understanding of why even more is on the cards in future.

“This is the first study that suggests a possible intensification of droughts in the tropic-subtropical margins in warmer climate,” Professor Fu says. “The finding is critical to understanding what the world will be like as the climate continues to change.

“Will the Hadley Circulation continue to expand? Could the intensification of droughts over the tropics be a new norm? These are questions that need to be answered.” – Climate News Network

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Serious doubts over Europe’s GHG reduction target

Serious doubts over Europe’s GHG reduction target

Europe has made substantial progress in cutting greenhouse gas emissions, but its long-term reduction aims look unachievable, says a new report.

LONDON, 9 March, 2015 − The 28 countries of the European Union (EU) have set themselves a collective target of cutting emissions of climate-changing greenhouse gases (GHGs) by between 80% and 95% by 2050, but  a major report just released says there’s little hope of achieving that goal.

Every five years, the European Environment Agency (EEA) produces a comprehensive study, and the latest says projected declines in GHG emissions are not nearly enough to reach the long-term target of decarbonising most of Europe’s economy by mid-century.

The report says there has been considerable progress in recent years on reducing Europe’s GHG emissions to 19.2% below 1990 levels. while, at the same time, gross domestic product across the EU has increased by 45%. EU per capita emissions fell from 11.8 tonnes of CO2 equivalent in 1990 to 9 tonnes in 2012.

The trouble is that this progress is very unlikely to be maintained over the long term unless the entire EU economy is revamped and there are very substantial investments in renewables.

Hard part ahead

The cut in GHG emissions was largely achieved through economic restructuring in eastern Europe following the collapse of the old Soviet Union and associated states. Polluting energy and industrial plants were closed, and agricultural practices modernised.

The 2008 economic crisis also caused a dip in emissions, while EU policies aimed at achieving greater energy efficiency have also played an important role in reducing emissions.

That, in many ways, was the easy part. Now comes the big challenge: in order to achieve its long-term emissions reduction objective, Europe needs a wholesale reorganisation of its economy, says the EEA, and also needs to become less resource-hungry.

Fossil fuels still dominate energy production, accounting for 75% of energy supply in 2011 − the most recent year for which comprehensive statistics are available.

Progress achieved

“The EU will need to accelerate its implementation of new policies, while restructuring the ways that Europe meets its demand for energy, food, transport and housing,” the report says.

Short-term goals can be achieved, says the EEA, and the EU is on track to meet its target of producing 20% of its energy from renewable sources by 2020. Renewables accounted for 11% of EU energy production in 2012 – up from 4% in 1990.

It is a similar story across much of the European environment. Progress has been made over recent years in improving water systems, waste collection and recycling, and in rehabilitating some ecosystems.

“In many parts of Europe, the local environment is arguably in as good a state today as it has been since the start of industrialisation,” the report says. “Reduced pollution, nature protection and better waste management have all contributed.”

Worsening air

At the same time, what the report refers to as Europe’s natural capital is being seriously degraded by the activities of agriculture, fisheries, industries and  tourism. Urban sprawl is also having a negative impact.

In some regions, ecosystems are in a dire state, and the EU is not on track to meet its 2020 target on halting biodiversity loss.

Air quality is a particular concern.  The EEA estimates that more than 400,000 people in Europe died prematurely in 2011 due to breathing in toxic fumes. In some areas, air quality is getting worse, not better. And land is under severe pressure.

The report says that “loss of soil functions, land degradation and climate change remain major concerns, threatening the flows of environmental goods and services that underpin Europe’s economic output and well-being”. −  Climate News Network

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Prices fail to reflect fossil fuels’ real costs

Prices fail to reflect fossil fuels' real costs

The price consumers pay for the fossil fuels we use are appreciably lower than their true cost to society, US researchers say, and by the same logic renewables are seriously over-priced.

LONDON, 8 March, 2015 − Forget the price of petrol at the pumps. The true cost of any fossil fuel is much greater if social costs are factored in, according to new research.

A climate scientist in the US reports in Climatic Change journal that American motorists get a gallon of gasoline for at least $3.80 less than it really costs, and the price of coal-fired electricity would quadruple if consumers had to pay the real price. In contrast, solar and wind power are much cheaper than they might seem.

Professor Drew Shindell, of Duke University in Durham, North Carolina, has been calculating the economic entity called social cost − a measure of all the other burdens, charges, and impositions that arrive with a quantity of goods sold on the open market.

In particular, he has focused on all the health, climate and environmental problems that are linked to emissions from fossil fuels, biomass burning, and agriculture.

Harder to quantify

All these exact a price from society as a whole, but the motorist or the tractor driver or the industrialist doesn’t pay for the harder-to-quantify costs of air pollution, healthcare, falling crop yields, lost work and school days, or higher insurance premiums against flood and other weather extremes.

The US government has already proposed “social cost” accounting to price the emission of carbon dioxide to the atmosphere from fossil fuels at $37 per metric ton of carbon dioxide emitted. The purpose of such notional values is to help planners work out which steps are likely to be the most cost-effective.

Other scientists have already suggested such calculations are far too low. One recent study suggested the true figure should be six times higher. Another has pronounced the governmental basis for its calculations as flawed, and a third team has suggested that no matter what the cost of action, the price paid for doing nothing would be higher.

“We are making decisions based on misleading costs”

The new study is yet another attempt to provide a framework for economic calculations that reflect the new reality of climate change.

“We think we know what the prices of fossil fuels are, but their impacts on climate and human health are much larger than previously realised,” Prof Shindell warns. “We are making decisions based on misleading costs.”

Potent pollutants

His new economic models include damage from potent but short-lived climate pollutants such as methane and aerosols, as well as longer-lived greenhouse gases such as nitrous oxide. He also challenges the US Energy Information Administration’s estimated generation costs of 10 cents per kilowatt hour for coal, 13 cents for solar energy, eight cents for wind power and seven cents for natural gas.

“Not surprisingly, the US has seen a surge in the use of natural gas, the apparent cheapest option. However, when you add in environmental and health damages, costs rise to 17 cents per kilowatt hour for natural gas and a whopping 42 cents for coal,” he says.

“There is room for ongoing discussion about what the value of atmospheric emissions should be. But one thing there should be no debate over is that the current assigned price of zero is not the right value.” – Climate News Network

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Poorest nations seek US-EU lead on climate deal

Poorest nations seek US-EU lead on climate deal

Hopes that this year’s UN climate talks will produce an effective global treaty to cut emissions may rest on richer countries setting far more ambitious targets.

LONDON, 7 March, 2015 – Quamrul Chowdhury, a lead negotiator for the Least Developed Countries bloc at UN climate talks, is concerned that the US and European Union are failing to give the lead they should on emissions reductions.

Visiting the UK to speak at universities in Oxford and London, he told the Climate News Network: “With the US and the EU, we expect both to raise their level of ambition to mitigate climate change. Only if they take the lead can we reach consensus.”

Chowdhury, an energetic and familiar figure at the annual UN climate conferences, said of this year’s treaty negotiations in Paris in December: “I’m optimistic, but it’s going to be a Herculean task. We’ll have to make a lot of compromises and collapse our red lines if we are to achieve an ambitious, robust treaty.”

Binding target

The US plans to reduce its emissions by 26%-28% from their 2005 levels to achieve “economy-wide reductions in the order of 80% by 2050”. The EU plans a binding, economy-wide domestic reduction target for 2030 of at least 40% from 1990 levels.

But Chowdhury believes this is not enough, and that both must go further. “This range of ambition will not add up to an aggregate level that takes us to the internationally-agreed goal of preventing global average temperature rise exceeding 2°C, much less 1.5°C,” he said.

“We need to cut emissions faster than that. If the Americans and Europeans don’t do so, other countries will not be ready to raise their level of ambition.”

The LDCs insist that the developed world must act first − an argument that has preoccupied many previous negotiations.

“The developed countries are the leaders − it’s their responsibility,”  Chowdhury said. “If they can give that lead, other countries will follow. We’ve contributed an insignificant amount of greenhouse gases.

We can’t afford not to agree a legally-binding treaty . . . If we fail, the most vulnerable countries will be the victims

“The US and the EU are doing quite well, but we need more ambition or else the gap will be so huge. We have to move faster in the short time left to negotiate, otherwise the most vulnerable countries’ situation will be catastrophic.”

The LDCs, many of them already bearing the brunt of the climate onslaught, are prepared to give ground for the sake of an agreement.

“We always want to make compromises,” Chowdhury said. “We’ve shown flexibility in the past, and we’re ready to do so now − to go the extra mile. Billions of people are on the receiving end of climate change.”

However, it’s not clear whether the LDCs will cut their own emissions. Chowdhury said: “If we reach an agreement in Paris, there will be from us what some call a commitment, and others describe as an intention, to make cuts.

“There are so many ifs and buts, though, so much mathematics. We agree in principle to cuts, but we can’t say at this stage what they’ll be.

Effective treaty

“For the effective treaty we need, the means of implementation are essential. We’ll need money to pay for technology transfer, capacity building and helping our economies through the transition of adapting. The money will need to be predictable, new, additional and easily accessed.”

The LDCs won’t rush to judgement in the Paris talks. Chowdhury said: “They’ll be a success, first, if we get a treaty with raised ambition. But while the process of implementing that treaty will start in January 2016, the end results won’t be achieved till 2020.”

Some commentators say that hopes for Paris are high because countries will be asked to meet lowered expectations − in other words, that any treaty attainable won’t offer much.

Chowdhury sees it differently. “We can’t afford not to agree a legally-binding treaty in December”, he said. “If we fail, the most vulnerable countries will be the victims. We shall have to suffer much more, and we can’t afford any longer to let that happen.” − Climate News Network

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Urgent campaign to curb pollutants’ deadly effects

Urgent campaign to curb pollutants’ deadly effects

Carbon dioxide is public enemy No 1 in the fight against climate change, but other pollution is having a big impact − and causing millions of premature deaths.

LONDON, 6 March, 2015 − They are called short-lived climate pollutants (SLCPs), but they play a significant role in global warming, as well as leading to serious health problems.

Although they exist for far shorter time spans in the atmosphere than CO2, the SLCPs can cause serious changes in climate in that time, particularly in urban areas or in highly climate-sensitive zones such as the polar regions and major mountain ranges.

The SLCPs − which include methane, black carbon or soot, and hydrofluorocarbons − are particularly prevalent in some of the world’s poorest regions.

Soot and fumes

Firewood, cow dung and other fuels, incompletely combusted on millions of household fires, give rise to high levels of SLCPs − as does the black soot and fumes belching from the exhaust pipes of hundreds of thousands of trucks and buses. The smoke and fumes originating from small industrial concerns, such as brick factories, also contain high levels of black carbon.

This pollution is swept by the winds up onto high mountain ranges, falling on the snow and glaciers and darkening the surface. Losing its ability to reflect the sun’s heat, the surface warms and a process of melting is set in motion.

The Climate and Clean Air Coalition (CCAC) − initiated by the governments of Bangladesh, Canada, Ghana, Mexico, Sweden and the US, and the United Nations Environment Programme, and also comprising private sector groups and environmental organisations − was formed three years ago with the aim of curtailing SLCP emissions.

At a recent meeting in Kathmandu, the capital of Nepal, delegates were told that climate change was happening faster and in a dramatically more visible manner in the Earth’s cryosphere – the regions of ice and snow – than anywhere else on earth.

“Our work will contribute to the pathway of limiting global warming to 2˚C”

The consequences of increased melting in the Himalaya-Hindu Kush region are particularly serious.

According to the Kathmandu-based International Centre for Integrated Mountain Development, the area’s mountains store nearly 10% of the world’s freshwater. And many millions of people across one of the planet’s most densely populated regions are dependent on mountain waters for agriculture and other purposes.

The CCAC is launching a series of schemes to combat SLCPs, including giving funds to city authorities for soot-free bus fleets and programmes to encourage less polluting agricultural practices.

“Our work will contribute to the pathway of limiting global warming to 2˚C, harness health, food and energy benefits, and spur sustainable development,” says Hanne Bjurstroem, Norway’s special envoy for climate change, and a co-chair of CCAC.

The SLCPs are also a serious health hazard. According to the World Health Organisation (WHO), more than four million people die prematurely each year as a result of household air pollution.

The WHO estimates that 2.8 billion people cook and heat their homes by burning coal and biomass – wood, dung, crop wastes and other solid fuels – on open fires or basic stoves.

Cancer-causing

Fumes from these fires contain minute levels of toxic substances, such as carbon monoxide, nitrous and sulphur dioxides and formaldehyde. They often also contain particles of cancer-causing substances that can penetrate deep into the lungs.

Women and children, who spend most time in the home, are particularly vulnerable. More than 50% of premature deaths among children under five around the world, the WHO says, are due to pneumonia caused by particulate matter (soot) inhaled from household air pollution.

Solving the problem of SLCPs caused by household fires and other sources is not easy, but progress is being made in some areas.

In Nepal, the government says it is aiming for big cuts in SLCPs through various programmes, including the mass introduction of improved cooking stoves. The goal, it says, is to make Nepal free of indoor pollution by 2017. – Climate News Network

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CO2 fertiliser effect stimulates insect attacks on forests

CO2 fertiliser effect stimulates insect attacks on forests

Study in US forests shows that extra CO2 absorbed as the planet warms will encourage growth of leaves − but also the insects that eat them.

LONDON, 5 March, 2015 − Insects could be about to complicate things for climate scientists who want to model the carbon budget in a warming world.

As more carbon dioxide builds up in the atmosphere, the trees should respond, put on extra growth and soak up more carbon. But if herbivorous insects start to respond to a warmer world, this classic instance of what engineers call negative feedback could become a little more complicated.

Entomologists John Couture, and Richard Lindroth, and colleagues at the University of Wisconsin-Madison in the US, report in the journal Nature Plants on the results of a large-scale, extended outdoor experiment in which aspen and birch trees were subjected to heightened levels of carbon dioxide and ozone.

Although the trees had been planted in natural conditions, a network of pipes supplied the environment around them with levels of greenhouse gases predicted for 2060.

Extracted nutrition

The scientists collected leaf samples from the plantation canopy and detritus from the ground beneath the trees to begin a calculation of the production and loss of biomass every season. The cut leaves provided a clue to insect damage, and the insect excrement separately told a story of extracted nutrition.

They found that although the carbon dioxide did indeed fertilise the forests, the extra growth also stimulated insect attack. The levels of damage by very hungry caterpillars and other herbivores almost doubled. Every year, across ever square metre, insect pests and parasites consumed 70 grams of carbon-sequestering biomass.

“The big question is, will northern forests grow faster under elevated carbon dioxide?”

They found that if accompanying ozone levels were higher – and low-level ozone in some places could increase in a warmer world – then the losses were significantly less. Ozone is also toxic to plants, so this may not be of long-term comfort either.

“This is the first time, at this scale, that insects have been shown to compromise the ability of forests to take up carbon dioxide,” Professor Lindroth says.

The key word here is scale. The study was conducted in the real world, rather than in a laboratory or a computer simulation.

But it was still limited to a selection of sample plots, so the question remains open as to whether, at the global level, plants will take up more carbon, or whether the insects eat up the difference and return it to the atmosphere?

Carbon cycle

Research such as this is a reminder that the world is a complicated place, and the details of the carbon cycle are likely to go on giving climate scientists a headache for years to come.

The extra fertilisation by carbon dioxide didn’t make the trees more nutritious, or more appetising: if anything, the reverse. Think of the difference between processed white bread and a high-density, nourishing loaf from a master baker.

“There’s a lot more protein in the bakery bread than in the white bread,” Dr Couture says. “Insects have a base level of nutrients they need in order to grow, and to reach that they can choose either to eat higher-nutrient food – unfortunately insects don’t always have that choice – or to eat more.”

And Professor Lindroth adds: “The big question is, will northern forests grow faster under elevated carbon dioxide? Carbon dioxide is a substrate for photosynthesis. It gets converted into sugars, which then become plant biomass. Will trees take up more carbon dioxide, and thus help reduce its increase in the atmosphere?” – Climate News Network

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Climate change is likely factor in Syria’s conflict

Climate change is likely factor in Syria’s conflict

Researchers say climate change probably caused the savage drought that affected Syria nearly a decade ago − and helped to spark the country’s current civil war. 

LONDON, 2 March, 2015 – In a dire chain of cause and effect, the drought that devastated parts of Syria from 2006 to 2010 was probably the result of climate change driven by human activities, a new study says.

And the study’s authors think that the drought may also have contributed to the outbreak of Syria’s uprising in 2011.

The drought, which was the worst ever recorded in the region, ravaged agriculture in the breadbasket region of northern Syria, driving dispossessed farmers to the cities where poverty, government mismanagement and other factors created the unrest that exploded four years ago. The conflict has left at least 200,000 people dead, and has displaced millions of others.

The study, by scientists from Lamont-Doherty Earth Observatory at Columbia University, US, is published in the Proceedings of the National Academy of Sciences.

The authors are quite clear that the climatic changes were human-driven (anthropogenic) and cannot be attributed simply to natural variability, but are careful to stress that their findings are tentative.

“We’re not saying the drought caused the war,” says Richard Seager, one of the co-authors. “We’re saying that, added to all the other stressors, it helped kick things over the threshold into open conflict.

“And a drought of that severity was made much more likely by the ongoing human-driven drying of that region.”

Link with violence

Their study, although it contains new material, is not the first to suggest a possible link between extreme weather and the likelihood of violence.

Some researchers have investigated whether there may be a link between El Niño and La Niña − the periodic Pacific weather disruptions − and outbreaks of unrest.

Syria was not the only country affected by the drought. It struck the Fertile Crescent, linking Turkey, Syria and Iraq, where agriculture and animal herding are believed to have started around 12,000 years ago.

Suggestions of a global connection between climate change and political instability is being taken seriously by two influential groups − insurers and military planners.

The Levant has always seen natural weather swings. Other research has suggested that the Akkadian empire, spanning much of the Fertile Crescent about 4,000 years ago, probably collapsed during a long drought.

Drought can lead to devastating consequences when coupled with pre-existing acute vulnerability

But the authors of the Lamont-Doherty study, using existing studies and their own research, showed that the area has warmed by between 1°C and 1.2°C since 1900, and has undergone a 10% reduction in wet-season precipitation.

They say this trend is a neat match for models of human-influenced global warming, and so cannot be attributed to natural variability.

Global warming has had two effects, they say. First, it appears to have indirectly weakened wind patterns that bring rain-laden air from the Mediterranean, reducing precipitation during the usual November-April wet season. And higher temperatures have increased the evaporation of moisture from soils during the hot summers.

The authors say an episode of this severity and length would have been unlikely without the long-term changes.

Other researchers have observed the long-term drying trend across the Mediterranean region, and have attributed at least part of it to anthropogenic warming.

The researchers say Syria was especially vulnerable because of other factors − including a huge increase in population from four million in the 1950s to 22 million in recent years.

Water-intensive crops

The government has also encouraged water-intensive export crops such as cotton, while illegal drilling of irrigation wells depleted groundwater, says co-author Shahrzad Mohtadi, an international affairs consultant at the US Department of State.

The drought’s effects were immediate and overwhelming. Agricultural production − typically, a quarter of Syria‘s gross domestic product − fell by a third. In the northeast, livestock was practically wiped out, cereal prices doubled, and nutrition-related diseases among children increased steeply.

As many as 1.5 million people fled from the countryside to cities already strained by waves of refugees from the war in neighbouring Iraq.

“Rapid demographic change encourages instability,” the authors say. “Whether it was a primary or substantial factor is impossible to know, but drought can lead to devastating consequences when coupled with pre-existing acute vulnerability.”

Solomon Hsiang, professor of public policy at the University of California, Berkeley, says the study is “the first scientific paper to make the case that human-caused climate change is already altering the risk of large-scale social unrest and violence”. – Climate News Network

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