Scientists zero in on only solution to climate crisis

Scientists zero in on only solution to climate crisis

Panel of international climate scientists says the world has only until 2050 to become a zero-carbon society − but the rewards for doing so would be immense.

LONDON, 22 April, 2015 – If you want to know what we have to do to avoid catastrophic climate change, 17 of the world’s leading climate scientists have worked out a simple but challenging solution: the world, they say, must turn by mid-century into a zero-carbon society.

The signatories to today’s “Earth Statement” say: “This trajectory is not one of economic pain, but of economic opportunity, progress and inclusiveness. It is a chance too good to be missed.

“The latest science indicates that there are critical thresholds in the Earth system. Transgressing them may lead to dramatic and irreversible environmental changes.

“We are probably edging very close to such thresholds, and may already have crossed one with regard to melting of parts of Antarctica. Sea-level rise of more than one metre due to this event alone may be inevitable.”

Window of opportunity

They are convinced that time is short. “The window of opportunity is closing fast,” says Johan Rockström, chair of the Earth League, an international group of scientists from leading research institutions working on issues caused by climate change, natural resource depletion, land degradation and water scarcity.

“We are on a trajectory that will leave our world irrevocably changed, far exceeding the 2°C mark. This gamble risks disaster for humanity, with unmanageable sea-level rise, heat waves, droughts and floods.

“We would never consider this level of risk in any other walk of life, yet we seem prepared to take this risk with our planet. Conversely, the scientific evidence shows that we can create a positive future, but only with bold action now.”

The 2°C threshold is the limit beyond which world leaders have agreed to prevent global temperatures rising as climate change intensifies.

“For the sake of fairness, rich countries and progressive industries can and should take the lead and decarbonise well before mid-century”

The Earth League’s first Earth Statement is issued as a warning ahead of the UN climate conference in Paris in December − referred to by the UN Framework Convention on Climate Change as COP21, the 21st conference of the parties to the original climate treaty.

The League is supported in its statement − published today to mark Earth Day, an annual reinvigoration of the global environmental movement − by the Global Challenges Foundation.

Professor Jeffrey Sachs, director of the Earth Institute at Columbia University, US, and one of the authors of the statement, says: “COP21 is the moment of truth − the last chance to stay within the 2°C upper limit.

Quality of life

“The key to success is deep decarbonisation by mid-century. Our studies show that this can be accomplished, at modest cost, and with a significant improvement in the quality of life.”

The Earth Statement lists what it calls “eight essential elements of climate action”, which it says any agreement achieved in Paris in December should achieve in order to provide the world with a good chance of avoiding dangerous climate change.

They include the need for the process of deep decarbonisation to start immediately. One of the eight points, which may prove contentious, reads: “Equity is critical. Every country must formulate an emissions pathway consistent with deep decarbonisation.

“For the sake of fairness, rich countries and progressive industries can and should take the lead and decarbonise well before mid-century.”

Prof Rockström and Prof John Schellnhuber, a fellow Earth League member and director of the Potsdam Institute for Climate Impact Research, will present the Earth Statement tomorrow at the fourth Nobel Laureates Symposium on Global Sustainability in Hong Kong. – Climate News Network

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Carbon dioxide triggered ancient mass die-off

Carbon dioxide triggered ancient mass die-off

The biggest extinction ever known on Earth resulted from oceans turned acid by CO2, the main gas driving human-caused climate change today.

LONDON, 16 April, 2015 − Scientists have identified the lethal agency that caused the single most catastrophic event in the history of life on Earth. The mass extinction at the boundary of the Permian and Triassic eras 252 million years ago was caused by the acidification of the world’s oceans, as a consequence of an increase in atmospheric carbon dioxide.

The Permian Extinction – sometimes called “the Great Dying” – seemed to all but obliterate life in the oceans, and perhaps on land. More than 90% of all species disappeared, more than 80% of all genera, and more than 50% of all marine families were extinguished in one prolonged calamity.

All life on Earth today has descended from the few survivors of this far-off episode. Palaeontologists, geologists, climate scientists and astronomers have all speculated on the probable cause. The latest and most confident analysis is based on a new study of ancient marine sediments and delivers obvious parallels with processes that are – for different reasons − occurring again today.

Matthew Clarkson of the University of Edinburgh in Scotland (but now at the University of Otago in New Zealand) and colleagues report in the journal Science that they examined limestone from the United Arab Emirates and found, in the isotope ratios of the element boron, evidence of ocean acidity in carbonate rocks that were laid down as sediment at the bottom of the ocean 250 million years ago. A change in the isotope ratios, they calculated, would have indicated a significant shift in seawater chemistry.

“This is a worrying finding, considering that we can already see an increase in ocean acidity today that is the result of human carbon emissions”

Over the last 40 years, researchers have introduced a whole suite of plausible triggers for the Permian extinction, but at last one team had clear evidence of increased atmospheric carbon, probably from a prolonged and convulsive series of volcanic eruptions that gave rise to vast, ancient geological formations now known as the Siberian Traps.

“Scientists have long suspected that an ocean acidification event occurred during the greatest mass extinction of all time, but direct evidence has been lacking until now”, said Dr Clarkson. “This is a worrying finding, considering that we can already see an increase in ocean acidity today that is the result of human carbon emissions.”

There has been recent evidence that this present change in the pH of ocean waters (pH is a measure of its acidity) as a consequence of fossil fuel combustion in the last two centuries has already disturbed the behaviour of some fish species, threatened to affect oyster fisheries and coral reefs, and even to alter whole ocean ecosystems.

The changes in the Permian were not sudden: ecosystems already seriously under stress because of lack of oxygen or rising temperatures were then dramatically affected by discharges of carbon dioxide that were probably much greater than all the modern world’s existing fossil fuel reserves could deliver. As the oceans became more acidic, many species were extinguished forever: among them the trilobites.

The whole chain of events took 60,000 years. Humans have been burning fossil fuels for only 200 years, but, the researchers point out, in the Permian crisis, carbon was probably being released into the atmosphere at the rate of about 2.4 billion tons a year. Right now, humans are estimated to be releasing carbon from fossil fuels at the rate of 10 billion tons a year. − Climate News Network

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Permafrost holds key to release of trapped carbon

Permafrost holds key to release of trapped carbon

The frozen soil of the northern polar regions holds billions of tonnes of organic carbon – and global warming could speed its escape into the atmosphere.

LONDON, 14 April, 2015 − Three sets of scientists in the same week have helped narrow the uncertainties about how the natural world will respond to extra carbon dioxide in the atmosphere caused by the burning of fossil fuels.

Carbon locked in the frozen earth will escape gradually as the Arctic permafrost melts – but the scientists say the process could accelerate.

As greenhouse gas levels soar, and soils warm, and plant roots tap down into the carbon stored there by centuries of ancient growth, they will release potent chemicals that will accelerate microbial attack – and speed up the release of carbon dioxide into the atmosphere.

The soil carbon cycle is one of the great headaches of climate science. And the Arctic is the first place to look for answers about it, and about how the Earth and oceans that store atmospheric carbon will respond to global warming.

Locked away

Around half of the world’s buried organic carbon is locked away in the soils of the northern circumpolar permafrost, and this huge vault of deep-frozen peat and leaf litter – more than 1,000 billion metric tonnes in the top three metres, at the latest estimate − contains twice as much carbon as is held in the atmosphere.

But the Arctic is the fastest-warming region on the planet, so what will happen as the permafrost thaws and plants begin to move north? Would it all be surrendered to the atmosphere in one devastating exhalation, triggering an explosion in global warming and causing trillions of dollars in economic damage?

An international team within the Permafrost Carbon Network thinks not. Their verdict, published in Nature journal, is that the current evidence suggests “a gradual and prolonged release of greenhouse gas emissions in a warming climate”. That is, humankind would have time to adapt.

“The data from our team’s syntheses don’t support the permafrost carbon bomb view,” says one of the team members, David McGuire, professor of landscape ecology at the University of Alaska Fairbanks.

“What our syntheses do show is that permafrost carbon is likely to be released in a gradual and prolonged manner, and that the rate of release through 2100 is likely to be of the same order as the current rate of tropical deforestation in terms of its effects on the carbon cycle.”

Since the tropical forests are already under pressure, this is hardly good news. And the picture is not a simple one.

“Even small changes will have serious effects on carbon concentrations in the atmosphere, and by extension on climate”

As the permafrost thaws, the soil microbes will get to work on the buried carbon, which will inevitably add to the soil warming, and provide an instance of what engineers call positive feedback, according to a team led by Jøgen Hollesen, senior researcher at the University of Copenhagen’s Centre for Permafrost.

He and colleagues report in Nature Climate Change that when they measured heat production in 21 contrasting organic permafrost soils, they found it to be between 10 and 130 times higher than in mineral soils measured in Greenland − and this would have “crucial implications for the amounts of carbon being decomposed”.

And in the same issue of Nature Climate Change, a team led by researchers from Oregon State University have confirmed that any kind of warming or plant growth is likely to get the soil microbes working as hard as they can – partly because the plants use chemistry to free the soil carbon so the bacteria can start to turn it back into carbon dioxide.

Neither of the two Nature Climate Change studies was directly concerned with climate change. The Danish scientists’ findings sprang from concern about what warming might do to the ancient middens that hold as-yet-unexamined evidence of early human settlement in the Arctic. The Oregon team were more concerned about the interactions that go on in the soil, and how they could be measured.

Chemical bonds

They found that plant roots released an exudate that acted to release the chemical bonds that keep a carbon bound to non-organic minerals in the soil. Warming could only speed the process, so more carbon dioxide will get into the atmosphere from the soil because of global warming.

This, again, is positive feedback at work. And it suggests climate scientists might be underestimating carbon loss from the soil by as much as 1% a year.

“Our main concern is that this is an important mechanism, and we are not presently considering it in global models of carbon cycling,” says soil and environmental geochemist Markus Kleber, one of the authors of the Oregon report.

“There is more carbon stored in the soil, on a global scale, than in vegetation, or even in the atmosphere. Since this reservoir is so large, even small changes will have serious effects on carbon concentrations in the atmosphere, and by extension on climate.” – Climate News Network

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Investors chip in as renewables rise towards record level

Investors chip in as renewables rise towards record level

Climate-friendly boost for global energy mix as scientists say solar power alone could now meet the needs of California five times over.

LONDON, 12 April, 2015 − Carbon dioxide levels might be soaring, and governments might be slow to reduce fossil fuel emissions and contain climate change − but the smart money could nevertheless be going into renewable sources such as wind and solar power.

The United Nations Environment Programme (UNEP) says green energy investments rose by 17% in 2014 to reach a total of $270bn − the first annual increase in three years, and just 3% behind the all-time record set in 2011 of $279bn.

In 2014, renewable energies added 103 gigawatts to global capacity. This is roughly equal to the output of all 158 nuclear power reactors in the US.

Wind, solar, biomass, waste-to-power, geothermal, small hydro and marine power contributed an estimated 9.1% of world electricity generation in 2014. This also represents a notional saving in carbon dioxide emissions of 1.3 gigatonnes, which is about twice what pours from the exhausts of the world airlines.

Markets mature

“Once again in 2014, renewable made up nearly half the power capacity added worldwide,” said Achim Steiner, executive director of UNEP.

“These climate-friendly energy technologies are now an indispensable component of the global energy mix and their importance will only increase as markets mature, technology prices continue to fall and the need to rein in carbon emissions becomes ever more urgent.”

But, according to scientists backed by the Carnegie Institution, there is much more that could be done. A team led by Earth system scientists Rebecca Hernandez, now of the University of California Berkeley, reported in Nature Climate Change that solar energy alone could meet the demands of the state of California in the US up to five times over.

Solar power systems based on photovoltaics could generate up to 15,000 terawatts of energy a year. And mirror-driven concentrating systems could add another 6,000 terawatt hours.

California – now in the grip of a calamitous drought that has been tentatively linked to climate change triggered by human investment in fossil fuels – is the most populous state in the US. The researchers calculated that more than 27,000 square kilometres of land would be fit for photovoltaic solar construction, and more than 6,000 square kilometres for concentrating solar power.

“Their importance will only increase as markets mature, technology prices continue to fall
and the need to rein in carbon emissions becomes ever more urgent”

But there is a darker side to the story of renewable energy. On the other side of the Rocky Mountains, scientists have been working on the much more complex carbon budget of biofuels, which deliver energy in liquid form.

They count as renewable energy because, although they emit carbon dioxide when burned, they do not, overall, add to the levels of greenhouse gases in the atmosphere. That is because biofuel crops take carbon dioxide from the air to grow their tissues for conversion to fuel, and return the gas through engine exhausts.

But there have been persistent worries. One is that the conversion of food to fuel may not be the most efficient use of cropland.

Destroy ecosystems

The approach remains carbon neutral, as long as farmers exploit existing cropland. But the danger is that farmers might plough up existing grassland, destroy ecosystems, and release ancient stored soil carbon to the atmosphere, to make global warming worse.

Environmental scientist Tyler Lark and colleagues at the University of Wisconsin-Madison report in Environmental Research Letters that, between 2008 and 2012, US farmers ploughed seven million acres of new land for corn and soy for conversion to biofuels intended as renewable energy for motor transport.

In the course of doing so, they could have emitted as much carbon to the atmosphere as 34 coal-burning power stations in one year – or 28 million new cars on the road.

Nearly a quarter of the land converted came from long-standing prairies and ranges, much of it within the Central Plains, from North Dakota to Texas. And much of this was planted with corn intended for conversion to biofuels.

“It mimics the extreme land-use change that led to the Dust Bowl in the 1930s,” Lark says. “We could be, in a sense, ploughing up prairies with each mile we drive.” – Climate News Network

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Forests can soak up a third of carbon emissions

Forests can soak up a third of carbon emissions

Report commissioned by Prince Charles’s charity says protecting tropical forests could enable them to absorb billions of tonnes of the Earth’s emissions of carbon.

LONDON, 11 April, 2015 − Looking after the world’s tropical forests would be worthwhile in its own right, for the sake of their human and animal inhabitants and their wider effects on the natural world.

But researchers say it would also have a significant bonus. Properly cared for, the forests could cancel out between a quarter and a third of the planet’s carbon emissions.

They argue that it is not just outright destruction of the trees that is the problem, but the ways in which the forests become degraded by the incursion of different forms of development − logging, obviously, but also fires, mining, ranching, roads, and their effect in splitting the huge tracts of forested land into smaller and more isolated patches.

In a report commissioned by Prince Charles, the heir to the British throne, they say deforestation and degradation of the forests may account together for between 14% and 21% (1.4-2.2 gigatonnes of carbon, or GtC; a gigatonne is a billion metric tonnes) of all emissions of carbon, and perhaps even more if tropical peatlands and mangroves are included.

Atmospheric carbon

Against this, the forests absorb almost as much atmospheric carbon as they account for − an annual total of 1.2-1.8GtC, the authors say. But the report argues that simply offsetting the amount of carbon sequestered in this way against the amount emitted is insufficient, for two reasons.

The first is the evidence that human activities are responsible for a significant proportion of CO2 absorption. Second, total emissions are probably much higher than the traditional greenhouse gas (GHG) accounting approach allows.

Taken together, these two factors suggest that slowing damage to the forests and keeping them in the best condition possible is more important than many people have realised.

But the forests continue to suffer damage. The report says: “…it can be argued that the causes and consequences of tropical forest degradation have been given too little attention, with the science now pointing toward degradation being a very significant component both of greenhouse gas emissions and the weakening of forest ecosystems”.

We can act on forests now, therefore buying much-needed time to enable the transformation to a low-carbon economy

It paints a sobering picture of the present situation, saying there is “no sign yet that overall rates of deforestation or degradation are decreasing”. The report says the annual area of global forest lost is about 8.5m hectares.

Rising world demand for timber and wood products, and for farm produce, it says, “will significantly increase pressure on tropical forests over the next few decades”.

The report was commissioned by the Prince’s International Sustainability Unit. In a foreword, Prince Charles writes: “It is an alarming fact that rates of deforestation and degradation continue to rise, and that the underlying causes of this increase are set to become very much more acute…”

But he sounds an encouraging note: “We can act on forests now, therefore buying much-needed time to enable the transformation to a low-carbon economy.”

Considerable uncertainty

There is considerable uncertainty about how much the forests contribute to GHG emissions. In 2012, NASA said that tropical deforestation had accounted for about 10% of human carbon emissions from 2000 to 2005 − a much lower figure than previous estimates.

Forest degradation is often more difficult to detect than deforestation itself, and is almost invisible to satellite monitoring. Research in six tropical countries suggests that degradation by logging can cause significant damage, with GHG emissions on average about 12% of those caused by deforestation.

Together, their impact is serious. The Global Forest Watch online monitoring network says that Brazil lost 5.9% of its forest cover between 2001 and 2012, while Indonesia lost 9.2% over the same timespan. − Climate News Network

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Climate-driven loss of habitat endangers marine mammals

Climate-driven loss of habitat endangers marine mammals

Global survey of threatened Arctic species warns that conservation won’t work without regulation of greenhouse gas emissions to halt climate change.

LONDON, 2 April, 2015 − Three kinds of whale, six varieties of seal, the walrus and the polar bear all have things in common: they are marine mammals, they depend on the Arctic for survival as species, they are vulnerable, and biologists know surprisingly little about them.

And since the Arctic is warming twice as fast as the rest of the planet, their future could become even more threatened as climate change increases habitat loss.

The stress, so far, is on the word “could”, as the first challenge is to establish the facts.

A global study team led by Kristin Laidre, principal scientist at the University of Washington Polar Science Centre in Seattle, reports in the journal Conservation Biology that marine mammals are “disproportionately threatened and data poor compared with their terrestrial counterparts”.

The narwhal, beluga and bowhead whales, the ringed, bearded, spotted, ribbon, harp and hooded seals, the walrus, and the polar bear are “particularly vulnerable due to their dependence on sea ice”.

Important predators

All these animals make their living on the ice and in waters north of the Arctic Circle, and all are important predators. They are also important to indigenous and settler peoples in the frozen North as many can be legally harvested, and others are iconic tourist attractions. Either way, they help communities survive.

“These species are not only icons of climate change, they are also indicators of ecosystem health, and key resources for humans,” Dr Laidre says. “Accurate scientific data – currently lacking for many species – will be key to making informed and efficient decisions about conservation challenges and trade-offs in the 21st century.”

So the researchers set out on what they believe is the first comprehensive global review of what is known about the populations of these animals, and about the way their local habitats may be changing.

“They need ice to find food, find mates, reproduce, and rear their young. It’s their platform of life.”

The study divided the Arctic into 12 regions and began to look at population numbers and trends, and the local pattern of seasonal change in the ice.

They identified 78 distinct populations of the 11 species, and began to assemble estimates of numbers. These range from millions for the ringed seals to a few hundred for the beluga whales of Ungava Bay in the Canadian Arctic.

In many cases, researchers had too little information even to make a guess about whether local populations of any species were stable, declining or increasing. In their table of the trends of the 11 species in the 78 populations, the word “unknown” occurs more than 60 times.

They also charted profound reductions in ice cover. The sea ice naturally advances each winter, and retreats each spring, but because of global warming driven by human emissions of greenhouse gases released by fossil fuel combustion, the pattern of advance and retreat has changed dramatically. By 2040, according to some projections, the Arctic could be more or less ice-free each summer.

Extended summer

But change is visible now. In most regions, the scientists found that the summer period was extended by between five and 10 weeks. In Russia’s Barents Sea, the summer ice period is now 20 weeks longer – five months – than it was 30 years ago.

This presents a threat to the polar bear, and to the seals on which they feed. “These animals require sea ice,” Dr Laidre says. “They need ice to find food, find mates, reproduce, and rear their young. It’s their platform of life. It is very clear those species are going to feel the effects the hardest.”

On the other hand, the whale species might benefit – at least for a while – from reduced ice cover. Open water could offer a wider feeding range and greater marine productivity, and therefore more food.

The scientists provide a set of general recommendations for biologists, local authorities, government agencies and international organisations concerned with conservation of Arctic marine mammals. They also have a message for the entire planet.

As Dr Laidre says: “We may introduce conservation measures or protected species legislation, but none of those things can really address the primary driver of Arctic climate change and habitat loss for these species. The only thing that can do that is regulation of greenhouse gases.” – Climate News Network

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Pollution poses long-range danger to Borneo’s forests

Pollution poses long-range danger to Borneo's forests

Air quality in Borneo’s rainforests is being affected by pollution from human activities far off in East Asia – with possible consequences for the ozone layer.

LONDON, 1 April, 2015 – New evidence has been found of the long distances that airborne pollution can be transported, and of its potential impacts far from its point of origin.

Researchers from the UK and Malaysia have detected a human fingerprint deep in the Borneo rainforest in south-east Asia − and it has implications for air quality in the region, and for the ozone layer.

The research, published in European Geosciences Union journal Atmospheric Chemistry and Physics, shows that cold winds from the north carry industrial pollutants from East Asia towards the equator. The air quality in Borneo depends very much on which way the wind blows.

“On several occasions during northern-hemisphere winter, pockets of cold air can move quickly southwards across Asia towards south China and onward into the South China Sea,” says Matthew Ashfold, assistant professor in the School of Biosciences at the University of Nottingham’s Malaysia campus, and formerly of the University of Cambridge.

Cold surges

Prof Ashfold and his colleagues show that these “cold surges” can very quickly carry polluted air southwards. “The pollution travels about 1,000 km (620 miles) per day, crossing the South China Sea in just a couple of days,” he says.

They were originally looking for natural chemical compounds, to test whether the oceans around Borneo were a source of bromine and chlorine, but they also detected another gas called perchloroethene, or perc, in the air samples they collected from two sites in the Borneo forest.

“This gas is a common ‘marker’ for pollution because it does not have natural sources,” Prof Ashfold explains.

“Our measurements . . . . show that what is happening at the surface in industrialised middle latitudes can have an important impact elsewhere”

The team found evidence suggesting that the high levels of perc in the samples were influenced by East Asian pollution.

Perc is produced in industrial and commercial activities, such as dry cleaning and metal degreasing, and exposure to large amounts (above about 100 parts per million) can affect human health.

Global emissions have declined in the last 20 years or so, but it is not clear whether this applies to East Asia, where air pollution has increased over that period.

The researchers say the levels of perc measured in Borneo are low, at a few parts per trillion. But because the gas does not occur naturally, even small concentrations are a sign that other more common pollutants − such as carbon monoxide and ozone − are present, and levels of all three gases fluctuate at similar rates.

Ozone in high concentrations can damage forests by reducing plant growth, and is also a human health risk.

Poorer air quality in the remote rainforest is not the only consequence of the pollution.  Prof Ashfold says: “The atmosphere over south-east Asia and the western Pacific is home to unusually strong and deep thunderstorms during the northern hemisphere winter. Because of this, the region is an important source of air for the stratosphere.”

There is a potentially two-way interaction between atmospheric composition and the climate.

One of the study’s co-authors, Professor John Pyle, from the Department of Chemistry at the University of Cambridge and director of the UK’s National Centre for Atmospheric Science, told the Climate News Network: “This study certainly exemplifies part of that feedback cycle.

Rapid lifting

“The mosaic of islands in Southeast Asia − our measurements are in Sabah, Malaysian Borneo − is a preferred region for very rapid lifting, sometimes within hours, of atmospheric compounds to higher levels.

“Some of these compounds − the industrially-produced halocarbons, and the halocarbons naturally emitted from the ocean, both of which we measure − are ozone-depleting substances.”

Both types of halocarbons and the ozone itself are greenhouse gases.

Professor Pyle says: “We aren’t arguing that our measurements indicate that there is a major climate impact, but they do nicely show that what is happening at the surface in industrialised middle latitudes can have an important impact elsewhere, with potential for important feedbacks to the surface.” – Climate News Network

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Rich nations urged to cut temperature rise targets

Rich nations urged to cut temperature rise targets

Senior scientist says voices of poorer nations must be heard in the political tussle over reducing the “utterly inadequate” global warming limit.

LONDON, 31 March, 2015 − The official target of limiting global warming to a 2˚C rise has been described by a senior scientist as “utterly inadequate” to protect the people most at risk from climate change.

That’s the conclusion reached by one of the authors of the recent Intergovernmental Panel on Climate Change (IPCC) assessment report, in an analysis of the political tussle between rich and poor nations at last December’s UN conference on limiting temperature rise.

Richer countries were happy to limit global average temperature rises to 2˚C, while middle and low-income nations would have preferred to contain warming within 1.5˚ C or lower.

Possibilities of calamity

But Dr Petra Tschakert, associate professor at Pennsylvania State University’s Earth and Environmental Systems Institute, reports in the journal Climate Change Responses that the agreed limit contains within it the possibilities of calamity for many people.

“The consensus that transpired during this [UN conference] session was that a 2˚C danger level seemed utterly inadequate, given the already observed impacts on ecosystems, food, livelihoods and sustainable development,” Dr Tschakert says.

“A low temperature target is the best bet to prevent severe, pervasive and potentially irreversible impacts, while allowing ecosystems to adapt naturally, ensuring food production and security, and enabling economic development to proceed in a sustainable manner.”

Her analysis is not of itself new, nor is it much disputed − other leading scientists have also warned that such an international agreed limit could be disastrous.

But her commentary in the journal reveals something of the debate among the government representatives and experts who must meet and prepare for global action.

Global average temperatures have been creeping up at fractions of a degree per decade for more than 30 years, and some degree of further global warming is now inevitable.

Scientists at the IPCC have from the start warned that – without steps to dramatically reduce the combustion of fossil fuels – the planet could warm by 4˚C or more, and sea levels could rise by up to a metre by 2100. In 2009, governments met in Copenhagen and settled on a limit of 2˚C.

“This should happen now, and not only when climate change hits the rich world”

But this target has always been contested. More than 100 poorer nations and small island states − such as Tuvalu, recently pounded by a tropical cyclone Pam − have repeatedly said that a 2˚C rise is unsafe, and called for a 1.5˚C limit.

The World Health Organisation argued at the December UN meeting that, as far as human health was concerned, there was no safe limit, and people already faced hazards from undernourishment, and from food and water-borne infections.

Heatwaves, such as the one that hit Russia in 2010, may have caused 10,000 additional deaths, while floods, hurricanes and other extreme weather events are likely to be more frequent and more severe hazards in a 2˚C world.

Climate impacts

Dr Tschakert’s argument is that a global average limit may be a convenient and compelling instrument for discussing climate change impacts, but nobody in the world actually faces a global average.

Such a notional limit is the average of extremes and variation across regions, all of which are subject to different hazards − ranging from glacial melting to coral bleaching − that could be disastrous for people in those regions, many of whom are among the world’s poorest.

Dr Tschakert says: “These implications emphasise what is truly at stake – not a scientific bickering of what the most appropriate temperature target ought to be, but a commitment to protect the most vulnerable and at-risk populations and ecosystems, as well as the willingness to pay for abatement and compensation..

“This should happen now, and not only when climate change hits the rich world.” – Climate News Network

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China ramps up the rhetoric on climate change

China ramps up the rhetoric on climate change

Senior Chinese official warns that climate-related temperature rises could seriously affect the country’s harvests and major infrastructure projects.

LONDON, 28 March, 2015 − Zheng Guogang, head of the China Meteorological Administration, says future variations in climate are likely to reduce crop yields and damage the environment.

In one of the strongest official statements to date on the challenges faced, Zheng told China’s official Xinhua news agency that climate change could have a “huge impact” on the country, with a growing risk of climate-related disasters.

“To face the challenges from past and future climate change, we must respect nature and live in harmony with it,” Zheng said. “We must promote the idea of nature, and emphasise climate security.”

Violent rainstorms

Zheng said temperature rises in China over the past century have been higher than the global average. He warned that river flows and harvests are likely to suffer as the incidence of droughts and violent rainstorms across the country increases.

In turn, this could affect major infrastructure projects such as the Three Gorges Dam on the Yangtze river, the biggest hydroelectric scheme in the world.

Other projects that could be hit by changes in climate are the rail line between the northwestern province of Qinghai and Tibet − the highest railway line in the world, and partly built on permafrost − and a massive project aimed at bringing water from the south of China to the parched towns and cities of the north.

“The safe production and operation of major strategic projects is facing a serious threat,” Zheng said.

Although millions of people in China have benefited from years of double-digit economic growth, damage to the environment has been extensive and has become a major social, health and political issue.

“To face the challenges from past and future climate change, we must respect nature
and live in harmony with it”

China is now the world’s biggest emitter of greenhouse gases − largely due to its continued reliance on coal for power generation.

There are frequent public protests about the state of the environment, particularly water and air pollution. In Beijing and several other cities, air pollution frequently exceeds internationally-recognised health safety limits.

The authorities are taking various measures to tackle the country’s considerable environmental problems, but they are nervous about public protests on the environment getting out of control.

Earlier this month, “Under the Dome” – a documentary on China’s pollution, made by one of the country’s leading investigative reporters − was taken down from the internet by the authorities after having been viewed by an estimated 100 million people.

Green development

Under China’s present five-year plan, which started in 2011, there is a focus on the need to encourage “green, cyclical and low-carbon development”.

The plan claims: “These actions will increase the strategic position of combating climate change in China’s overall economic and social development.”

In an effort to improve its environment and meet international obligations to cut emissions, China is in the midst of a renewable energy programme costing billions of dollars.

Late last year, Beijing announced for the first time a date when the country’s emissions would peak – 2030 – and then taper off in the years following.

China is also involved with the US and other countries in a wide range of energy-saving research projects aimed at combating climate change. – Climate News Network

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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 Holocene, 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 Crutzen, 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,” Crutzen 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.”

Crutzen 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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