Galleries

Climate change slows onset of next ice age

The planet’s inexorable warming means there will be no new ice age for at least the next 100,000 years, scientists say.

LONDON, 18 January, 2016 – Human beings have not just started to leave a unique geological stratum that will announce their existence long after the species has been extinguished. They may have altered a climate cycle that has been stable for millions of years and even cancelled – or certainly postponed – the next Ice Age.

Andrey Ganopolski and colleagues from the Potsdam Institute for Climate Impact Research in Germany report in Nature that they took a look at the conditions that determined the geologically recent cycle of Ice Ages.

The advance and retreat of vast glaciers over geological time are the consequence of a mix of factors involving sea, mountains, atmosphere, vegetation and the distribution of continents around the globe.

But ultimately what determines the rhythm of these events is what climate scientists call insolation: how much sun the Earth actually gets in a summer. The Earth’s orbit is not a perfect circle but an ellipse, and the shape of the ellipse and the angle of the Earth’s tilt on its axis change subtly and imperceptibly over cycles lasting tens of thousands of years, which in turn alters the amount of sunshine striking the northern hemisphere.

And if the atmospheric levels of carbon dioxide are not high when the total insolation is near its lowest point, great thick sheets of ice begin to advance over Europe, Asia and North America.

This is enough to explain the last eight Ice Ages. The sequence is punctuated by “interglacials” that tend to last roughly 10,000 years before the ice advances once more.

But at the end of the last Ice Age something happened: humans had discovered fire, and then used it to invent agriculture and metal foundries, and then began to alter the carbon balance in the atmosphere, even before the discovery of fossil fuels.

“We are basically skipping a whole glacial cycle, which is unprecedented. It is mind-boggling that humankind is able to interfere with a mechanism that shaped the world as we know it”

Geologists have a name for this present interglacial epoch. They call it the Holocene. “Even without man-made climate change we would expect the beginning of a new ice age no earlier than in 50.000 years from now – which makes the Holocene as the present geological epoch an unusually long period in between ice ages,” Dr Ganopolski said.

“However, our study also shows that relatively moderate additional anthropogenic CO2 emissions from burning oil, coal and gas are already sufficient to postpone the next ice age for another 50.000 years.

“The bottom line is that we are basically skipping a whole glacial cycle, which is unprecedented. It is mind-boggling that humankind is able to interfere with a mechanism that shaped the world as we know it.”

Geologists have already proposed that the Holocene be renamed the Anthropocene, from the Greek anthropos for mankind. The interest in the Ice Age mechanisms is not new: in the 1970s, climate scientists began to ask whether a glaciated world could come back.

Within a decade, it became clear that atmospheric carbon dioxide levels would be too high to permit another immediate Big Freeze, and would go on rising.

What the Potsdam scientists have done, using climate simulations, is to pinpoint the intricate balance of insolation and atmospheric chemistry that controls the beginning and the end of an Ice Age.

Continuing rise

And once humans had begun to exhume all the ancient sunshine of the Carboniferous Period that ended 300 million years ago, and return it to the 20th century atmosphere as greenhouse gases, the combustion products of coal, oil and methane, the cycle was interrupted.

It is likely to stay warm for a period far longer than all recorded human history so far. Even if humans drastically reduce the combustion of fossil fuels this century, enough will enter the atmosphere to keep carbon dioxide levels high, and global temperatures and sea levels will go on rising.

“Like no other force on the planet, ice ages have shaped the global environment and thereby determined the development of human civilisation. For instance, we owe our fertile soil to the last ice age that also carved out today’s landscapes, leaving glaciers and rivers behind, forming fjords, moraines and lakes.

“However, today it is humankind with its emissions from burning fossil fuels that determines the future development of the planet,” said Hans Joachim Schellnhuber, director of the institute and one of the authors.

“This illustrates very clearly that we have long entered a new era, and that in the Anthropocene humanity itself has become a geological force. In fact, an epoch could be ushered in which might be dubbed the Deglacial.”

Andrew Watson, of the University of Exeter, UK, said the study confirmed what he and others had suspected for some time. “Humans now effectively control the climate of the planet.

If only we were wise enough to be able to use that power responsibly, this might be a good thing, as a planet that avoided major ice ages would probably be better for most of the species living on it. Unfortunately, I don’t think we’ve reached that level of wisdom yet.” Climate News Network

Markets cannot solve the climate crisis

How did we get to where we are now? “Free range” capitalism could be the explanation for climate change, and needs taming, says one writer.

LONDON, 28 December, 2015 – It may not be polite to mention Karl Marx in America, but leading thinkers on the left think that capitalism may be the cause of climate change, and that to save the planet the system needs fundamental reform.

According to a new book the profit motive, which drives capitalism above all other considerations, forces it to extract everything from the planet that will generate a surplus, at the expense of real benefits to humans and ecosystems.

Fossil Capital: the Rise of Steam Power and the Roots of Global Warming, by Andreas Malm, out in hardback from Verso in January 2016, analyses capitalism’s role in global warming by delving into its past.

The book builds on the work of Naomi Klein’s 2014 This Changes Everything: Capitalism vs the Climate. Both ask whether catastrophic climate change can be averted without at least a major makeover – or the outright elimination – of capitalism.

Malm, a professor of human ecology at Sweden’s Lund University, starts with James Watt’s patenting of the rotating steam engine in 1784. This was also the first year that rising carbon dioxide and methane levels were observed in polar ice.

First Malm attacks the accepted theories of David Ricardo and Thomas Malthus. who developed and reinforced the capitalist notion that markets are the cure for all social ills. He shows that mills adopted coal power instead of water only because it enabled mill owners to move to populated areas to find docile and skilled workers, who were in short supply in the countryside.

More biddable

Coal enabled this move because, once out of the ground, it is highly portable. The machines, of course, eliminated many jobs and made others both simpler and more difficult. Owners started hiring women and children because they were easier to control than adult men.

The demands of the machines set the pace of work, and it was only after massive strikes and riots in the 1840s that a ten-hour workday was established; but this, Malm shows, only caused the mill owners to speed up the machinery and make workers adapt further, producing more in less time.

This in turn increased the demand for coal. The energy transition fostered a “bourgeois fantasy” that self-sustaining machines, godlike in their power but also biddable, would create a golden age.

Malm frames non-fossil energy – air, water and light – as “the flow”, a constant movement of forces not generated by humans that can sometimes be harnessed for human ends. Coal – and by extension all further fossil fuels – is “the stock”, something manufacturers can buy, accumulate, and use at need.

Humans were extremely vexing to the industrialists, because they behaved more like the flow than the stock. Coal-powered engines drastically reduced manufacturers’ dependence on human workers.

Dispensing with people

“The engine is much more tractable and civil than the hod-man,” wrote Edward Tufnell, a member of the Factories Enquiry of 1833, “easier managed, keeps good hours, drinks no whiskey, and is never tired.”

Thus, Malm asserts, capital’s switch from water to coal, and even later to oil, resulted fundamentally from an attempt to dispense with the services of human workers to the greatest possible extent. “Some humans introduced steam power against the explicit resistance of other humans,” he writes.

Workers were aware of this from the beginning. The millions who flocked to northern British cities, dispossessed by enclosures of formerly public lands, nonetheless hated the factories.

Scotsmen, Malm notes, viewed factories as prisons – and for good reason: the average temperature inside a steam-powered textile factory was 84-94°F (29-34°C).

Levels of carbon dioxide in the air could reach 2,800 parts per million – ten times the atmospheric levels at the time. The faster the mill owners pushed their machines, the more boiler explosions occurred, killing nearly one person a day in the 1850s.

But labour was eventually crushed with the aid of government soldiers. Coal was king, and the rest is history. This should be a cautionary tale for the present – if government allies with capital rather than the citizenry, Malm asserts, there will be no stopping climate change.

“People must try at least to modify free-range capitalism, echoing the cries of workers who challenged capital in the world’s first general strike in 1842: Go and stop the smoke!

The grandiose schemes for geo-engineering and other technical fixes bankrolled by the likes of Bill Gates, the major oil companies and the American Enterprise Institute,says Malm, would keep mitigation in the wrong hands – and in any case are too dangerous to try.

Insisting that the real authors of the climate crisis comprise a tiny, all-male, all-white fraction of the planet’s population, Malm objects to calling this the Anthropocene epoch; he would rather call it the “Capitalocene.” And capital, he insists, is not capable of solving the crisis it created.

What we need instead, he writes, is a return to “the flow”: distributed solar, wind and water power. Moreover, in order to avoid severe damage to civilisation, we need to abandon carbon immediately, and this can be accomplished only by intentional and decisive governmental action.

The governments that are doing best at this, Malm observes, are state and city governments, which have no obligation to generate profits and are not owned by Big Capital.

Malm recognises that “socialism is an excruciatingly difficult condition to achieve.” He’s not envisioning a new Stalinist nightmare to replace runaway capital. For one thing, Malm observes, capitalist ideology is so deeply ingrained in society that, quoting Marxist theorist Fredric Jameson, “It is easier to imagine the end of the world than the end of capitalism.”

Still, he says, people must try at least to modify free-range capitalism, echoing the cries of workers who challenged capital in the world’s first general strike in 1842: “Go and stop the smoke!” – Climate News Network

ISBN-13: 978-1-78478-129-3 paperback

Valerie Brown, based in Oregon, US, is a freelance science writer focusing on climate change and environmental health. She is a member of the National Association of Science Writers and Society of Environmental Journalists.

http://www.vjane-arts.com/vjane-arts/writing.html;

Twitter: @sacagawea

Paris attacks cast shadow over climate talks

Organising a climate change conference involving nearly 200 countries has been made considerably more difficult by the recent shootings in Paris.

LONDON, 18 November, 2015 – Heads of state, presidents, prime ministers, and royalty. Delegations from at least 190 countries. An estimated 3,000 journalists. Dozens of NGOs and assorted lobby groups. They are all due to converge on the beleaguered city of Paris in less than two weeks’ time.

But the recent terrorist mayhem in the French capital – resulting in the deaths of at least 129 people and injuries to hundreds of others − has made it a Herculean task to stage the huge UN climate change conference that is seen as vital for heading off potentially catastrophic global warming.

The climate talks – officially known as the 21st Conference of the Parties (COP21) to the 1992 UN Framework Convention on Climate Change (UNFCCC) – constitute one of the world’s biggest and arguably most important conferences. It is being held at Le Bourget, a conference and airport complex about 10 kilometres north-east of the centre of Paris.

The French government and UNFCCC have said the conference will go ahead, albeit amid what is described as “enhanced security”.

Le Bourget is less than a 10-minute taxi ride from Stade de France, the sports stadium and site of one of the major explosions last Friday evening.

Difficulties intensified

With the whole of France currently in a state of emergency, security at the climate talks will be very tight. Any demonstrations by protesters against the causes of climate are likely to be closely controlled.

For journalists covering events – particularly those who want to follow proceedings both within and outside the conference hall – life will be difficult.

Journalists from developing world countries are already at a disadvantage compared with their western counterparts. Though many are keen to be in Paris and to report on events, their media organisations often lack the funds to send staff to the French capital.

Journalists from many developing countries also have to go through considerable visa formalities, and this can act as a further disincentive to covering the talks.

Yet these journalists often come from countries already feeling the effects of climate change, and where reporting on it is most needed.

Unbalanced studies

A recent study led by academics at the University of Copenhagen found a profound imbalance in the way analysis of climate change is conducted around the world.

The study, which appears in the journal Global Environmental Change, found that countries most vulnerable to climate change are largely disconnected from the production and flow of scientific knowledge on the issue.

The small amount of research that is carried out on climate change in developing countries often lacks any locally-based personnel.

“Without locally-generated knowledge, it is more challenging to provide and integrate contextually relevant advice, and this leaves a critical gap in the climate policy debates”, says Maya Pasgaard, lead author of the study and a post-doctoral researcher in the Department of Geosciences and Natural Resource Management at the University of Copenhagen.

“This is particularly worrying as we are dealing with countries that are likely to experience severe climatic changes, and that are most sensitive to its detrimental impacts.” – Climate News Network

*Climate News Network is running a free training workshop from 1-3 December for developing world journalists who are in Paris for COP21. For further information on the course and how to register for a place, please visit our website.

Mangroves face struggle to survive in rising seas

Higher sea levels and diminishing deposits of estuary silt will endanger the survival of many mangrove forests across the Pacific Ocean.

LONDON, 19 October, 2015 – In less than one human lifetime, some of the planet’s richest and most vital coastal habitats could disappear. Sea-level rise is expected to flood and drown the mangrove forests of much of the Indo-Pacific.

These subtropical and tropical intertidal forests – home to huge varieties of fish, birds and insects, and natural buffers that protect coasts and estuaries during tropical cyclones – are at risk even if sea level rise is at the bottom of the predicted range, according to Catherine Lovelock, an ecologist at the University of Queensland.

She and colleagues report in Nature that they considered not just rates of sea level rise at a network of 27 sites, but changes in what scientists call “surface elevation” in the mangrove forests of the region: that is, the rate at which estuary silt is being deposited around the mangrove roots.

In the Chao Praya River delta in Thailand, for instance, sediment delivery has been cut by 80% and the coastal mangroves are in retreat.

The scientists found that, in 69% of their examples, the supply of sediment would not keep pace with changes in sea level: that is, by 2070, many forests would be submerged. These would include ecosystems in Thailand, Sumatra, Java, Papua New Guinea and the Solomon Islands.

Adaptation impossible

“Our modelling shows mangroves are likely to persist in east Africa, the Bay of Bengal, eastern Borneo and north-western Australia – areas where there are relatively large tidal ranges and/or higher sediment supply,” Professor Lovelock said.

Although sea levels are projected to rise by a metre or possibly more by the end of the century, under natural conditions the forests could adapt: estuaries would deliver enough mud and silt to enable the mangrove trees to keep, so to speak, their heads above water, and the forests would anyway begin to colonise the higher ground as the tides rose.

But since humans started damming rivers to build hydro-electric plants or to supply cities with water or farmland with irrigation channels, the annual delivery of river silt has steadily fallen.

Many estuaries, and the cities built on them, are subsiding even as tide levels steadily increase because of global warming, thermal expansion (the way that warmer water expands), and the steady melting almost everywhere of glaciers and icecaps to deliver more water to the seas.

Providing protection

By 2100, researchers have calculated, coastal flooding could be costing the world US$100,000 billion a year as a consequence of higher sea levels, higher temperatures and greater extremes of wind and rain, all driven by increasing greenhouse gas emissions from the combustion of fossil fuels.

Mangrove forests, like coral reefs, serve as natural barriers against floods, freak tides and storm surges. The forests also soak up significant quantities of atmospheric carbon and could play an important role in containing climate change. Altogether the Indo-Pacific region is home to most of the world’s mangrove forests. It is also expected to have high rates of sea level rise.

The Nature team believes that city, national and regional authorities should be thinking about conservation, restoration and better management of the forests upstream, and about the rivers that carry the decaying organic material that nourishes the coastal mangrove forests.

“Intertidal mangrove forests occur on tropical and subtropical shorelines, and provide a wide range of ecosystem services – to fisheries, in coastal protection and carbon sequestration – with an estimated value of $194,000 per hectare per year,” Professor Lovelock said. – Climate News Network

Climate changes can kick in below 2°C limit

Sudden shifts in settled climates can occur long before global warming reaches the internationally-agreed safety level, European scientists say.

LONDON, 18 October, 2015 – Climate change could arrive with startling speed. New research has identified at least 37 “tipping points” that would serve as evidence that climate change has happened – and happened abruptly in one particular region.

And 18 of them could happen even before the world warms by an average of 2°C,  the proposed “safe limit” for global warming.

Weather is what happens, climate is what people grow to expect from the weather. So climate change, driven by global warming as a consequence of rising carbon dioxide levels, in response to more than a century of fossil fuel combustion, could be – for many people – gradual, imperceptible and difficult to identify immediately.

But Sybren Drijfhout, of the University of Southampton in the UK and his collaborators in France, the Netherlands and Germany, are not so sure.

They report in the Proceedings of the National Academy of Sciences that they “screened” the massive ensemble of climate models that inform the most recent reports from the Intergovernmental Panel on Climate Change, and found evidence of abrupt regional changes in the ocean, the sea ice, the snow cover, the permafrost and in the terrestrial biosphere that could happen as average global temperatures reached a certain level.

The models did not all simulate the same outcomes, but most of them did predict one or more abrupt regional shifts.

No safe limit

But the future is not an exact science. “Our results show that the different state-of-the-art models agree that abrupt changes are likely, but that predicting when and where they will occur remains very difficult,” said Professor Drijfhout. “Also, our results show that no safe limit exists and that many abrupt shifts already occur for global warming levels much lower than two degrees.”

The idea of a “tipping point” for climate change has been around for decades: the hypothesis is that a climate regime endures – perhaps with an increasing frequency of heat waves or windstorms or floods – as the average temperatures rise. However, at some point, there must be a dramatic shift to a new set of norms.

The researchers explore some of the telltale indicators of such abrupt change. One of these would be the wholesale collapse of the Arctic Ocean winter ice: the Arctic is expected to be largely ice-free most summers in the next few decades. Winter ice would then become increasingly thin. Once sufficiently thin, warming and wave power would do the rest, and tend to leave clear blue water even in the coldest seasons.

Another indicator would involve massive unexpected plankton blooms in the Indian Ocean as a consequence of an upwelling of nutrient-rich waters from the ocean bottom, in response to changes in the Asian monsoon regime.

A third would involve massive snow melt on the Tibetan plateau: in 20 years, the annual average snow cover could fall from 400 kilograms per square metre to a trifling 50kg.

A fourth signal would be massive dieback in the Amazon rainforest over a few decades, mainly because of reduced rainfall.

Early signs

Yet another telltale aspect of climate change has already been addressed by Professor  Drijfhout. It would be the sudden, paradoxical dramatic drop in temperatures in the North Atlantic, as a response to global warming and a collapse of the ocean current that carries warm surface water north, while denser, colder and increasingly more saline water in the Arctic sinks to the bottom and flows back southward. This “overturning circulation” has already seemed to weaken as the Arctic has warmed.

In one of the team’s climate model simulations, the Atlantic circulation system keeps ticking over until about 2020. For another 20 years, sea and air temperatures vary wildly and the ocean current weakens much more swiftly. After about 2040, ice starts to form on the North Atlantic. By 2060, the circulation system has collapsed and the sea ice starts to spread.

“Increase of sea ice in the whole Atlantic sector of the Arctic causes a temperature decrease of more than 4 °C in a 20°-wide latitude band (55°N−75°N), stretching from 60°W to 40°E”, the scientists say. South of 40°N and outside the Atlantic, global warming continues. Only a portion of oceans in northern Europe would see dramatic cooling.

But that is a result from only one model of a number which predict varying levels of change for Europe.

The researchers add that the models aren’t perfect: they don’t simulate some things that really could happen, and perhaps show signs of happening now. They conclude:
“An additional concern is that the present generation of climate models still does not account for several mechanisms that could potentially give rise to abrupt change.

“This includes ice sheet collapse, permafrost carbon decomposition, and methane hydrates release.” – Climate News Network