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Scientists Solve a Decades-Old Mystery in Earth’s Upper Atmosphere

Dec. 18, 2013 — New research published in the journal Nature resolves decades of scientific controversy over the origin of the extremely energetic particles known as ultra-relativistic electrons in Earth’s near-space environment and is likely to influence our understanding of planetary magnetospheres throughout the universe.

• 
• • George Monbiot
  • The Guardian, Tuesday 17 December 2013 07.45 AEST
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A man walks past a coal plant in Lingwu, northern China. ‘Research suggested by Greenpeace suggests that a quarter of a million deaths a year could be avoided if coal power [in China] were shut down.’ Photograph: Stringer/China/Reuters

Most of the afflictions wrongly attributed to nuclear power can rightly be attributed to coal. I was struck by this thought when I saw the graphics published by Greenpeace on Friday, showing the premature deaths caused by coal plants in China. The research it commissioned suggests that a quarter of a million deaths a year could be avoided if coal power there were shut down. Yes, a quarter of a million.

Were Greenpeace to plot the impacts of nuclear power on the same scale, the vast red splodges depicting the air pollution catastrophe suffered by several Chinese cities would be replaced by dots invisible to the naked eye.

This is not to suggest that there are no impacts, but they are tiny by comparison. The World Health Organisation’s analysis of the Fukushima disaster concludes that “for the general population inside and outside of Japan … no observable increases in cancer rates above baseline rates are anticipated“. Only the most contaminated parts of Fukushima prefecture are exposed to any significant threat: a slight increase in the chances of developing cancer. Even the majority of the emergency workers have no higher cancer risk than that of the general population. And this, remember, was caused by an unprecedented disaster. The deaths in China are caused by business as usual.

The tiny risk that is imposed by nuclear power has both obscured and invoked the far greater risk that is imposed by coal. Scare stories about nuclear power are a gift to the coal industry. Where they are taken seriously by politicians – as they have been in Japan – and cause a switch from nuclear to coal power, they kill people.

Since the tsunami in 2011, the internet has been awash with ever more lurid claims about Fukushima. Millions have read reports claiming that children on the western seaboard of the United States are dying as a result of radiation released by the damaged plant. It doesn’t seem to matter how often and effectively the stories are debunked: they keep on coming. But children in the US really are dying as a result of pollution from coal plants, and we hear almost nothing about it.

Plenty of reports also propose that the water on the Pacific coast of North America is now dangerous to swimmers, and the fish there too radioactive to eat. Again, it’s not true. Except in the immediate vicinity of the plant, any extra radiation to which fish in the Pacific are exposed is minute by comparison to the concentration in their tissues of polonium-210, which occurs naturally in seawater. There are, however, genuine dangers associated with another toxic contaminant found in fish: mercury. What is the primary source of mercury pollution? Ah yes, coal burning.

In October, for the first time, the World Health Organisation officially listed both gaseous outdoor pollution and airborne particulates as carcinogenic to humans. Exposure levels, it notes, are rising sharply in some parts of the world. In 2010 an estimated 223,000 deaths from lung cancer were caused by air pollution.

But these cancers, though wildly outstripping those correctly attributed to man-made radiation, are just a small part of the pollution problem. Far greater numbers are afflicted by other diseases, including asthma, bronchitis, emphysema, heart disease, hypertension, strokes, low birth weight, pre-term delivery, pre-eclampsia and (through heavy metal exposure in the womb) impaired brain function.

Three hundred micrograms of fine particulates per cubic metre of air is classed as severe pollution, the point at which children and elderly people should not leave their homes. As Greenpeace points out, in Shanghai a fortnight ago and in Harbin in October concentrations of particulates exceeded 500 micrograms. By far the greatest source of these particles is coal burning. In total, air pollution in northern China – according to a study published in Proceedings of the National Academy of Sciences – has cut average life expectancy by five and a half years.

We have exported much of our pollution – and its associated deaths – but the residue in our own countries is still severe. A study by the Clean Air Task Force suggests that coal power in the US causes 13,200 premature deaths a year. In Europe, according to the Health and Environment Alliance, the figure is 18,200. A study cited by the alliance suggests that around 200,000 children born in Europe each year have been exposed to “critical levels” of methylmercury in the womb. It estimates the health costs inflicted by coal burning at between €15bn (£12.5bn) and €42bn a year. Do you still reckon coal is cheap?

You’re picturing filthy plants in Poland and Romania, aren’t you? But among the most polluting power stations in Europe, Longannet in Scotland is ranked 11th; and Drax, in England, is ranked seventh. Last week the House of Lords failed to pass an amendment that would have forced a gradual shutdown of our coal-burning power plants: they remain exempted from the emissions standards that other power stations have to meet.

While nuclear power is faltering, coal is booming. Almost 1,200 new plants are being developed worldwide: many will use coal exported from the US and from Australia. The exports are now a massive source of income for these supposedly greening economies. By 2030 China is expected to be importing almost five times as much coal as it does today. The International Energy Agency estimates that the global use of coal will increase by 65% by 2035. Even before you consider climate change, this is a disaster.

You don’t have to be an enthusiast for atomic energy to see that it scarcely features as a health risk beside its rival. I wonder whether the nuclear panic might be a way of not seeing. Displacement is something we all do: fixing on something small to avoid engaging with something big. Coal, on which industrialism was built – and which over the past 200 years has come to seem central to our identity – is an industry much bigger and nastier and more embedded than the one we have chosen to fear. I don’t believe our choice is accidental.

• Twitter: @georgemonbiot. A fully referenced version of this article can be f

Corn crops in New Florence, Missouri, wither in the devastating drought of 2012. Photograph: MCT via Getty Images

An international scientific research project known as the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), run by 30 teams from 12 countries, has attempted to understand the severity and scale of global impacts of climate change. The project compares model projections on water scarcity, crop yields, disease, floods among other issues to see how they could interact.

The series of papers published by the Proceedings for the National Academy of Sciences (PNAS) shows that policymakers might be underestimating the social and economic consequences of climate change due to insufficient attention on how different climate risks are interconnected.

Europe, North America at risk

One paper whose lead author is Franziska Piontek of the Potsdam Institute for Climate Impact Research explores impacts related to “water, agriculture, ecosystems, and malaria at different levels of global warming.” The study concludes that:

“… uncertainty arising from the impact models is considerable, and larger than that from the climate models. In a low probability-high impact worst-case assessment, almost the whole inhabited world is at risk for multisectoral pressures.”

The uncertainties in the model are large enough that they may “mask” the risk of a “worst case” scenario of “multisectoral hotspots,” where impacts affecting “water, agriculture, ecosystems, and health” overlap in ways that could affect “all the world’s inhabited areas.”

In the worst-case analysis, “Almost the entire global population is exposed to multisectoral pressure” at global mean temperatures of around 4C higher, with “roughly 18% of the global population” projected to “experience severe pressure in all four sectors. The affected regions are in Europe, North America, and south-east Asia.”

How likely is this scenario? The study points out that:

“This worst case is rather extreme, but nonetheless it represents the upper end of the risk spectrum in light of the large uncertainties.”

Robust policy decisions to aid mitigation and adaptation strategies therefore require further research to understand “how impacts in different sectors overlap, as overlapping impacts increase exposure, lead to interactions of impacts, and are likely to raise adaptation pressure.”

Chronic water scarcity

Other papers point to significant risks that are much more likely on a business-as-usual emissions trajectory.

A study led by Jacob Schewe of Potsdam finds that “the combination of unmitigated climate change and further population growth will expose a significant fraction of the world population” – potentially as much as “100%” – to “chronic or absolute water scarcity.”

About 2.7C above preindustrial temperatures:

“… will confront an additional approximate 15% of the global population with a severe decrease in water resources and will increase the number of people living under absolute water scarcity (<500m3 per capita per year) by another 40% (according to some models, more than 100%) compared with the effect of population growth alone.”

The Mediterranean, the Middle East, the southern United States and southern China, for example, could see a “pronounced decrease of available water,” while southern India, western China, and parts of eastern Africa could see an increase.

The study results represent the multiple-model average of 11 hydrological models produced by five different climate models. While some areas like southern India, western China and eastern Africa could see an increase of available water, others like the Mediterranean, the Middle East, the southern United States and southern China, would see a “pronounced decrease of available water” without curbs in greenhouse gas emissions.

Agricultural collapse

Water scarcity in turn will have a dramatic impact on agriculture. Another study in the PNAS collection combining climate, agricultural and hydrological models warns that freshwater shortages could double climate change’s debilitation of global food crop yields.

Current agricultural models estimate that climate change will directly reduce food production from maize, soybeans, wheat and rice by as much as 43 percent by the end of the 21st century, encompassing a loss of between 400 and 2600 petacalories of food supply. But incorporating hydrological models reveals that when accounting for the decline of freshwater availability, there would be an additional loss of 600 to 2900 petacalories – potentially wiping out quantities equivalent to the total present-day food supply.

Such devastating potential losses could, however, be ameliorated by more efficient use of available surplus freshwater. The paper recommends “increases in irrigation capacity and efficiency” to be complemented by “efforts to increase water use efficiency and soil conservation in rainfed systems as well, which have a demonstrated capacity to boost crop yields without further exploiting freshwater resources in rivers and aquifers.”

Other findings of the range of studies show that increases in river flooding are expected in more than half of the areas investigated, and that the frequency of drought may increase by more than 20% in some regions.

Potsdam director Prof Hans Joachim Schellnhuber, who co-authored several papers in the PNAS special feature, said:

“There is an elephant in the room: current and future climate change impacts. But strangely, many people seem to be blind to it. Many decision makers prefer to turn a blind eye to global warming consequences, while many scientists tend to focus on very specific aspects of climate change. So we resemble the fabled blind men, who unknowingly touch different parts of the same elephant: grasping the animal’s trunk, one of the men is convinced he has a snake in his hand, whilst one other mistakes the tail for a rope. To recognize the animal, they must talk to each other to properly identify the individual parts and to bring them together. This is exactly what this international project does.”

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Global Map Predicts Locations for Giant Earthquakes

Dec. 12, 2013 — A team of international researchers, led by Monash University’s Associate Professor Wouter Schellart, have developed a new global map of subduction zones, illustrating which ones are predicted to be capable of generating giant earthquakes and which ones are not.