Cutting warming to 1.5°C could put food supply at risk

Cutting warming to 1.5°C could put food supply at risk

Scientists say meeting the tougher demands of many countries on limiting global temperature rise may be technically feasible, but would risk worsening world hunger.

LONDON, 21 May, 2015 – As world leaders try to agree how to prevent global warming from heating the planet by more than 2°C above pre-industrial levels, scientists have tackled an altogether thornier question: can we keep the rise below 1.5°C?

The lower target − demanded by more than 100 countries as a safer goal − is attainable, they say. But there will be little room for error, and getting there will mean not only cutting greenhouse gas emissions, but actually removing carbon dioxide from the atmosphere.

That is not possible with the technology now available. And even if it could one day be done, it would probably have forbiddingly harmful consequences for world food supplies.

However, limiting temperature rise by 2100 to less than 1.5°C is still feasible, say the researchers from the International Institute for Applied Systems Analysis (IIASA) in Austria, the Potsdam Institute for Climate Impact Research (PIK), Germany, and colleagues. They report their findings in the journal Nature Climate Change.

Similar actions

Not surprisingly, the answer includes doing more, and doing it faster. “Actions for returning global warming to below 1.5°C by 2100 are in many ways similar to those for limiting warming to below 2°C,” says IIASA climate researcher Joeri Rogelj, one of the lead authors of the report.

The authors accept that the economic, political, and technological conditions for achieving even 2°C are “substantial”. The negotiations to be held in Paris in December by member states of the UN Framework Convention on Climate Change (UNFCCC) may show what chance there is of meeting them.

The new study identifies key ways of reaching the 1.5°C target by 2100. One is a tight limit on future carbon emissions.

Gunnar Luderer, PIK senior researcher in sustainable solutions, who co-led the study, says: “In 1.5°C scenarios, the remaining carbon budget for the 21st century is reduced to almost half, compared to 2°C scenarios.

“As a consequence, deeper emissions cuts are required from all sectors, and global carbon neutrality would need to be reached 10-20 years earlier than projected for 2°C scenarios.”

Energy efficiency will also need to improve faster, he says.

“The scenarios we assess keep warming
to the lowest levels currently considered
technologically feasible”

But the study finds that staying below 1.5°C would require a radical step change: some time this century, carbon emissions would have to become negative at a global scale.

That is the scientists’ way of saying that significant amounts of CO2 will have to be actively removed from the atmosphere. And there is at present no known way of doing that.

In theory, it is possible − for example, through bio-energy use, combined with carbon capture and storage. But that is a technology that so far remains untested on a large scale.

It would also increase hunger, as the crops needed to produce enough biofuel would compete for land with food plants.

Another idea is to grow more forests, which would sequester carbon in their trees, but this would be open to the same objection − that it would reduce cropland. The higher temperatures in prospect will themselves affect forest growth and health.

Lowest levels

Rogelj told the Climate News Network: “Increased temperatures can make afforestation efforts harder. However, the scenarios we assess here keep warming to the lowest levels currently considered technologically feasible, and this issue will thus have a relatively smaller impact.”

Whatever happens, the authors expect things to get hotter before they have any chance of cooling down.

Rogelj says: “Basically, all our 1.5°C scenarios first exceed the 1.5°C temperature threshold somewhere in mid-century, before declining to 2100 and beyond as more and more carbon dioxide is actively removed from the atmosphere by specialised technologies.”

Over 100 countries worldwide more than half the members of the UNFCCC, including the Alliance of Small Island States (AOSIS) and the Least Developed Countries (LDCs) have declared their support for a 1.5°C target. – Climate News Network

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Tree-based farming could deliver abundant benefits

Tree-based farming could deliver abundant benefits

In addition to mitigating the effects of climate change, forests can help alleviate hunger and provide a safety net for some of the world’s poorest people.

LONDON, 8 May, 2015 – Forests may be the green investment with the richest returns for humankind, according to new research.

While one study outlines the ways in which forests provide food, fuel, shelter and a safety net for more than a billion humans, a separate one confirms that a canopy of older, sturdier trees helps protect the saplings and juvenile growths against heat and drought.

An international team of more than 60 scientists collaborated on a report − Forests, Trees and Landscapes for Food Security and Nutrition: a Global Assessment Report − just published by the International Union of Forest Research Organisations (IUFRO).

“Large-scale crop production is highly vulnerable to extreme weather events, which may occur far more frequently under climate change,” says Christoph Wilburger, who co-ordinated the IUFRO initiative. “Science shows that tree-based farming can adapt far better to such calamities.

Key role

“We know that forests already play a key role in mitigating the effects of climate change. This report makes it very clear that they also play a key role in alleviating hunger and in improving nutrition.”

Climate scientists tend to consider forests as “carbon sinks” − agencies that soak up carbon dioxide from the atmosphere and that could help counter the rising levels of the greenhouse gas released by the burning of fossil fuels.

But forests also have a role in water storage and in protecting land from the forces of erosion.

Forest fruits and nuts are an important nutrition source for many. The iron content of the dried seeds of the African locust bean and raw cashew nut can, for instance, match the flesh of chickens. And forests are shelter for sources of wild meat, fish and edible insects.

“Extensive losses of forest canopy . . . will amplify the effects of climate change”

In developing countries, around 2.4 billion households use wood and charcoal for cooking and heating, and forests deliver a multitude of what are sometimes called ecosystem services − such as supporting bees and other crop pollinators, delivering fodder for village livestock, and protecting streams and watersheds.

Worldwide, the lower the levels of prosperity, the higher the dependence on forests. In the Sahel region of Africa south of the Sahara, trees contribute on average four-fifths of household income − mostly through shea nut production.

The report also points out that the expansion of agricultural land accounts for 73% of forest loss worldwide.

Increasing threat

But if forests keep people safe, what keeps a forest in leaf when drought, extremes of heat and the attrition of climate change are also an increasing threat?

Solomon Dobrowski, of the Forest Landscape Ecology Lab at the University of Montana, and colleagues report in Global Ecology and Biogeography that the regeneration of future forests could depend on shelter from the extensive canopy provided by the adult trees in mature woodland.

Juvenile trees are more shallow-rooted and more vulnerable to high winds, intense sunlight, high temperatures and extended drought. Without a shady, protective canopy, they could suffer. And without juvenile trees, a forest could only decline.

Professor Dobrowski warns: “Extensive losses of forest canopy from disturbances such as severe wildfire will amplify the effects of climate change.” – Climate News Network

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Well drilling has deep impact on Great Plains’ health

Well drilling has deep impact on Great Plains' health

Loss of vegetation on North America’s vast rangelands as a result of a huge increase in oil and gas wells invokes memories of the 1930s Dust Bowl disaster.

LONDON, 27 April, 2015 − Oil wells and natural gas may have made individual Americans rich, but they have impoverished the great plains of North America, according to new research.

Fossil fuel prospectors have sunk 50,000 new wells a year since 2000 in three Canadian provinces and 11 US states, and have damaged the foundation of all economic growth: net primary production − otherwise known as biomass, or vegetation.

Brady Allred, assistant professor of rangeland ecology at the University of Montana’s College of Forestry and Conservation, and colleagues write in the journal Science that they combined years of high-resolution satellite data with information from industry and public records to track the impact of oil drilling on natural and crop growth.

They conclude that the vegetation lost or removed by the expansion of the oil and gas business between 2000 and 2012 added up to 10 million tonnes of dry vegetation, or 4.5 million tonnes of carbon that otherwise would have been removed from the atmosphere.

Loss of fodder

Put another way, this loss amounted to the equivalent of fodder for five million cattle for one month from the rangelands, and 120 million bushels of wheat from the croplands. This wheat equivalent, they point out, adds up to the equivalent of 13% of the wheat exported by the US in 2013.

Net primary production – the biomass that plants make from photosynthesis every day, all over the world – is the basis of all wealth and food security. It underwrites all other human and animal activity.

Human wealth depends ultimately on what grows in the ground, or what can be dug from the ground, and most of the latter – such as coal, oil and peat– was once stuff that grew in the ground.

The same net primary production is the basis of what economists sometimes call ecosystem services on which all civilisation depends: the natural replenishment of the water supply, the pollination of crops, the provision of natural nitrogen fertilisers, and the renewal of natural habitat for wild things.

“It took catastrophic disruption of livelihoods and economies [in the 1930s] to trigger policy reforms that addressed environmental and social risks of land-use change”

And what worries the conservation scientists is that this loss of net primary production is likely to be “long-lasting and potentially permanent, as recovery or reclamation of previously drilled land has not kept pace with accelerated drilling”.

“This is not surprising because current reclamation practices vary by land ownership and governing body, target only limited portions of the energy landscape, require substantial funding and implementation commitments, and are often not initiated until the end life of a well.”

They say that the land actually taken up by wells, roads and storage facilities just between 2000 and 2012 is about 3 million hectares. This is the land area equivalent to three Yellowstone National Parks.

The hydraulic fracturing, or “fracking”, used to extract oil and gas is between 8,000 cubic metres and 50,000 cubic metres per well, which means that the total quantity of water squirted into the ground at high pressure during the 12 years to 2012 could exceed 33,900 million cubic metres. At least half of this was used in areas already defined as “water-stressed”.

New wells

The researchers considered the drilling of new wells in Alberta, Manitoba and Saskatchewan in Canada, and in Colorado, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, Utah and Wyoming in the US.

Although there is legislation, it is limited to lands subject to federal jurisdiction, and 90% of all drilling infrastructure is now on privately-owned land − at least, in the US.

A tanker drives past a flaring oil well in North Dakota. Image: Tim Evanson via Wikimedia Commons

A tanker drives past a flaring oil well in North Dakota.  Image: Tim Evanson via Wikimedia Commons

The study’s authors want decision-makers to confront the challenges of this kind of ecological disruption. There are lessons from history in all this, they warn.

“In the early 20th century, rapid agricultural expansion and widespread displacement of native vegetation reduced the resilience of the region to drought, ultimately contributing to the Dust Bowl of the 1930s,” they write.

“It took catastrophic disruption of livelihoods and economies to trigger policy reforms that addressed environmental and social risks of land-use change.” – 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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Eyes in the sky see seas rising alarmingly faster

Eyes in the sky see seas rising alarmingly faster

Scientists analysing sophisticated satellite data warn that rises in sea level more rapid than expected are increasing threats to coastal cities and food security.

LONDON, 27 March, 2015 − Satellite observations show that sea level rise may have been underestimated, and that annual rises are increasing.

A collaborative effort between maritime organisations and space agencies in measuring sea level rise has come to the conclusion that it has been increasing by 3.1 millimetres a year since 1993 – higher than previous estimates.

The evidence is growing from a number of recent studies of the ice caps that sea level rise is accelerating, posing a threat to many of the world’s largest and most wealthy cities − most of which are also important ports.

Many of these in the developing world have little or no protection against rising sea levels. Some in Europe – such as London and Rotterdam − already have flood barriers to protect areas below high tide or storm surge level, but  these will need to be replaced and raised in the next 30 years.

Delta areas in Egypt, Vietnam, Bangladesh and China – vital to each of the nation’s food supply – are already losing land to the sea.

Difficult to measure

One of the problems scientists have had in getting accurate worldwide data is that the sea does not rise evenly around the globe. This, added to the fact that in some places the land is sinking and in other places is rising, makes exact information difficult to measure from tide gauges.

Since 1991, it has been possible to measure the surface of the oceans across the entire globe by using satellite altimetry, whereby the satellite emits a signal towards the ocean’s surface and receives the reflected echo. The sea level is calculated from the round-trip time between the satellite and the sea surface and the position of the satellite along its trajectory.

While the data from tide gauges provides information about local changes relative to the land, the use of altimeter satellites enables the recording of data on a global basis.

Luciana Fenoglio-Marc, a scientist specialising in physical and satellite geodesy at the Technical University of Darmstadt, Germany, uses these and other satellite geodetic observation data in her research.

She is working with the European Space Agency and the European Organisation for the Exploitation of Meteorological Satellites, and in close consultation with the German Federal Institute of Hydrology and the Federal Maritime and Hydrographic Agency of Germany.

This lends credibility to the report that European coastal cities are not sufficiently prepared for the threats that climate change poses

The increase of around 3.1mm per year since 1993 indicates a marked rise in the average sea level when compared to previously recorded values, which show a sea level rise of between 1mm and 2mm per year in the 20th century.

In its fifth Assessment Report (AR5, 2013), the Intergovernmental Panel on Climate Change (IPCC) predicted a further increase in the global sea level of 30cm to 70cm by the end of the 21st century, based on a scenario involving a medium rate of global warming.

The report predicted that increases will not be even, but will have a greater impact on some regions than on others. The result could be coastal flooding and rising groundwater levels – an outlook that makes it essential to have a reliable data basis for dealing with the dangers this poses.

Protecting coasts from the rising seas will require considerable adaptations, particularly in such low-lying coastal regions as the North Sea coast of Germany and the many low-lying islands in the tropics.

Another aspect of the work with satellites is measuring ocean density to see how much water expansion − because of warming − is leading to sea level rise. A direct estimation of mass changes in the Mediterranean Sea show expansion to be the cause of an average sea level rise of about 2.1mm per year since 1993.

According to the IPCC, about 35% of the sea level increase between 1993 and 2010 was the result of thermal expansion, and the rest was due to melting ice and increasing run-off from land. But the latest observation shows this may not be true of the Mediterranean.

Too cautious

There is wide debate about whether the IPCC estimates of sea level rise have been too cautious, suggesting that the sea level will rise more than a metre this century – and some have even suggested that the rise could be two metres.

This is mainly because there has been uncertainty about how much of the huge icecap in Greenland, and most of all in Antarctica, would contribute to sea level rise by 2100 – if at all.

Research published since the IPCC estimates were made show that both icecaps will be large net contributors to sea level rise, and possibly much quicker than previously thought.

This lends credibility to the report last week that European coastal cities are not sufficiently prepared for the threats that climate change poses. The report − titled Underfunded, Unprepared, Underwater? Cities at Risk – is by the E3G non-governmental organisation, and it says governments across the European Union are leaving their major cities exposed to danger from climate change, including floods, heat waves and sea level rise.

Since it takes an average of 30 years from planning to complete construction of a major flood barrier to protect a city, the report warns that the problem needs to be given urgent consideration and funding. – Climate News Network

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Heat-tolerant beans could help keep millions fed

Heat-tolerant beans could help keep millions fed

Plant researchers say new varieties of a tropical crop essential to people’s survival in Africa and Latin America can withstand the effects of global warming.

LONDON, 26 March, 2015 − Scientists believe they may have found how to safeguard a staple tropical crop, on which hundreds of millions of people depend, from the depredations of climate change.

They have discovered − through conventional breeding rather than genetic modification − 30 new “lines” (varieties) of beans that will thrive in the higher temperatures expected later this century, and which will pose a particular threat to harvests in Africa and Latin America.

The new “heat-beater” beans, an important source of protein for around 400 million people, have been identified by plant breeders with the CGIAR global agriculture research partnership.

Steve Beebe, a senior CGIAR bean researcher, announced at a conference in Ethiopia: “This discovery could be a big boon for bean production because we are facing a dire situation where, by 2050, global warming could reduce areas suitable for growing beans by 50%.

Worst-case scenario

“Incredibly, the heat-tolerant beans we tested may be able to handle a worst-case scenario where the build-up of greenhouse gases causes the world to heat up by an average of 4°C.

“Even if they can only handle a 3°C rise, that would still limit the bean production area lost to climate change to about 5%. And farmers could potentially make up for that by using these beans to expand their production of the crop in countries such as Nicaragua and Malawi, where beans are essential to survival.”

Dr Beebe told the Climate News Network: “So far, so good. Some of the lines are also drought-tolerant, and some are resistant to Bean Golden Yellow Mosaic Virus.

“We are taking these beans into a new environment that we don’t know from the bean perspective. . . Will we find more surprises?

“There are two caveats. First, so far the best lines are small red types for Central America and parts of East Africa, so we have a long road to improve a range of grain types, colours, etc.

“The other issue is that we are taking these beans into a new environment that we dont know from the bean perspective. We have seen that a soil pathogen, pythium, is more severe. Will we find more surprises?”

Rising heat as climate change intensifies is expected to disrupt bean production in central and South American countries, including Nicaragua, Haiti, Brazil and Honduras. African countries thought to be at risk are principally Malawi and the Democratic Republic of the Congo, followed by Tanzania, Uganda and Kenya.

Many of the new heat-tolerant beans developed by the CGIAR scientists are “crosses” of the common bean − which includes pinto, white, black, and kidney beans − and the tepary bean, a hardy survivor cultivated since pre-Columbian times in what is now part of northern Mexico and the southwest US.

Highly nutritious

Beans are often called the “meat of the poor”. They are highly nutritious, providing not only protein but fibre, complex carbohydrates, vitamins, and other micronutrients. In addition to heat tolerance, CGIAR researchers are also breeding lines with a higher iron content, in an effort to tackle malnutrition.

The new beans are the result of CGIAR’s work to develop new crop varieties that can thrive in drastic weather extremes, based on research in its “genebanks”, which preserve the world’s largest seed collections of the most important staple crops.

The heat-beaters emerged from the testing of more than 1,000 bean lines − work that began as an effort to develop beans that could tolerate poor soils and drought.

The focus turned to heat-tolerance following a 2012 report from CGIAR scientists warning that heat was a much bigger threat to bean production than previously believed. − Climate News Network

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Rice serves up double measure of biofuel and fodder

Rice serves up double measure of biofuel and fodder

An inexpensive process developed in Japan will allow farmers to produce their own tractor fuel and cattle feed in one simple step.

LONDON,12 February, 2015 − Japanese scientists have found a potential answer to the biofuel dilemma that if you grow crops for energy, you have to sacrifice crops for food.

They report that they can now ferment rice to deliver ethanol, while making silage for cattle feed –and that it can all be done on the farm without need for any expensive off-site processes.

Mitsuo Horita, of the National Institute for Agro-Environmental Sciences in Tsukuba, Japan, and colleagues write in the journal Biotechnology for Biofuels that they used a process of solid-state fermentation known to temperate zone farmers everywhere: grass or cereal is harvested, compressed, sealed, and fermented in the absence of oxygen.

Pickled product

The outcome is a pickled product that is both nourishing and palatable to cattle during the winter months − and a mix of liquid hydrocarbon products that must be disposed of in ways that won’t pollute water supplies or harm fish and wildlife.

The Japanese research team packed harvested whole rice plants with yeast and enzymes into bales wrapped in impermeable film.

Sugars and starch in the rice were converted by the yeast into ethanol, which could then be drained and distilled for fuel. And at the end of the process, the bale still contained nourishing silage.

For each bale, after six months of fermentation, the researchers collected 12.4kg of pure ethanol, or alcohol − which is about 10 times more than anyone could expect from traditional silage fermentation. The bales also leaked effluent ethanol at the rate of about 1.7kg a bale.

“Our system simply builds upon traditional processes already used by farmers for producing silage for animal feed”

Biofuels are often seen as a solution that creates more problems. Will increased “green energy” mean high grain prices? Will specialist biofuel crops escape from the farms and cause wider problems for the environment? Could biofuels be more efficiently made from waste, or from natural sources not for the moment of any commercial value? This new approach sidesteps some nagging questions.

“Generally, the bottlenecks in second-generation biofuel production include the need for large facilities, bulky material transport, and complicated treatment processes, all of which are costly and consume a great deal of energy,” Horita says.

“What we’ve now demonstrated is a complete and scaled-up system that shows its potential in a practical on-farm situation. Instead of a complicated process requiring special facilities, our system simply builds upon traditional processes already used by farmers for producing silage for animal feed.

Zero waste

“It results in a high yield of ethanol, while producing good quality feed, with zero waste.”

In effect, the team has delivered fodder and tractor fuel in one step.

Fermentation takes longer than usual, but no extra energy needs to be supplied for the process, and the alcohol drawn off contained no insoluble particles, and so would make it easier to handle.

The researchers used a vacuum distiller to get at 86% of the baled alcohol, but they concede they must do more to improve both the yield and the recovery of the ethanol.

Meanwhile, they point out, they have shown the way to an on-farm fuel system that could help farmers in the developing world, and which exploits the same field for food and fuel at the same time. − Climate News Network

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Climate’s threat to wheat is rising by degrees

Climate’s threat to wheat is rising by degrees

Worldwide field trials show that just one degree of warming could slash wheat yields by 42 million tonnes and cause devastating shortages of this vital staple food.

LONDON, 17 January, 2015 − Climate change threatens dramatic price fluctuations in the price of wheat and potential civil unrest because yields of one of the world’s most important staple foods are badly affected by temperature rise.

An international consortium of scientists have been testing wheat crops in laboratory and field trials in many areas of the world in changing climate conditions and discovered that yields drop on average by six percent for every one degree Celsius rise in temperature.

This represents 42 million tonnes of wheat lost − about a quarter of the current global wheat trade − for every degree. This would create serious shortages and cause price hikes of the kind that have previously caused food riots in developing countries after only one bad harvest.

Global production of wheat was 701 million tonnes in 2012, but most of this is consumed locally. Global trade is much smaller, at 147 tonnes in 2013.

Market shortages

If the predicted reduction of 42 million tonnes per 1˚C of temperature increase occurred, market shortages would cause price rises. Many developing countries, and the hungry poor within them, would not be able to afford wheat or bread.

Since temperatures − on current projections by the Intergovernmental Panel on Climate Change − are expected to rise up to 5˚C this century in many wheat-growing regions, this could be catastrophic for global food supply.

Dr. Reimund Rötter, professor of production ecology and agrosystems modelling at the Natural Resources Institute Finland, said that wheat yield declines were larger than previously thought.

“Increased yield variability is critical economically as it could weaken regional and global stability in wheat grain supply and food security”

He said: “Increased yield variability is critical economically as it could weaken regional and global stability in wheat grain supply and food security, amplifying market and price fluctuations, as experienced during recent years.”

One of the crucial problems is that there will be variability in supply from year to year, so the researchers systematically tested 30 different wheat crop models against field experiments in which growing season mean temperatures ranged from 15°C to 26°C.

Temperature impact

The temperature impact on yield decline varied widely across field test conditions. In addition, year-to-year variability increased at some locations because of greater yield reductions in warmer years and lesser reductions in cooler years.

The scientists say that the way to adapt is to cultivate more heat-tolerant varieties, and so keep the harvest stable.

The results of the study − by scientists from the Finland, Germany, France, Denmark, Netherlands, Spain, United Kingdom, Colombia, Mexico, India, China, Australia, Canada and the United States − are published in Nature Climate Change.

Professor Martin Parry, who is leading the 20:20 Wheat Institute Strategic Programme at Rothamsted Research to increase wheat yields, commented: “This is an excellent example of collaborative research, which will help ensure that we have the knowledge needed to develop the crops for the future environments.” – Climate News Network

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The world we are shaping is feeling the strain

The world we are shaping is feeling the strain

The world risks being destabilised by human activity, scientists report, most of it the work of a rich minority of us.

LONDON, 16 January, 2015 – Humans are now the chief drivers of change in the planet’s physical, chemical, biological and economic systems according to new research in a series of journals. And the humans most implicated in this change so far are the 18% of mankind that accounts for 74% of gross domestic productivity.

And the indicators of this change – dubbed the “planetary dashboard” – are 24 sets of measurements that record the acceleration of the carbon cycle, land use, fisheries, telecommunications, energy consumption, population, economic growth, transport, water use and many other interlinked aspects of what scientists think of as the Earth System.

Although these indicators chart change since the start of the Industrial Revolution in the 18th century, the most dramatic acceleration – the scientists call it the Great Acceleration – seems to have begun in 1950. Some researchers would like to set that decade as the start of a new geological epoch, the Anthropocene, from Anthropos, the ancient Greek word for mankind.

On the eve of this year’s World Economic Forum in Davos, Switzerland, a team of scientists led by Will Steffen of the Stockholm Resilience Centre at Stockholm University and the Australian National University report in the journal Science that the world has now crossed four of nine planetary boundaries within which humans could have hoped for a safe operating space.

The four boundaries are climate change, land system change, alterations to the biogeochemical cycle that follow phosphorus and nitrogen fertiliser use, and the loss of a condition called “biosphere integrity”.

Past their peak

The scientists judge that these boundary-crossing advances mean that both present and future human society are in danger of destabilising the Earth System, a complex interaction of land, sea, atmosphere, the icecaps, natural living things and humans themselves.

“Transgressing a boundary increases the risk that human activities could inadvertently drive the Earth System into a much less hospitable state, damaging efforts to reduce poverty and leading to deterioration of human wellbeing in many parts of the world, including wealthy countries”, said Professor Steffen. “In this new analysis we have improved the quantification of where these risks lie.”

The Science article is supported by separate studies of global change. These were backed by the International Geosphere-Biosphere Programme, also headquartered in Stockholm, which publishes an analysis in the journal the Anthropocene Review.

Meanwhile a team of European scientists warn in the journal Ecology and Society that out of 20 renewable resources (among them the maize, wheat, rice, soya, fish, meat, milk and eggs that feed the world) 18 have already passed their peak production.

And a separate team led by scientists from Leicester University in Britain has even tried to pinpoint the day on which the Anthropocene era may be said to have commenced. In yet another journal, the Quaternary International, they nominate 16 July, 1945: the day of the world’s first nuclear test.

Unequal world

This flurry of research and review is of course timed to help world leaders at Davos concentrate on the longer-term problems of climate change, environmental degradation, and food security, in addition to immediate problems of economic stagnation, poverty, conflict and so on. But these immediate challenges may not be separable from the longer-term ones. To ram the message home, the authors will present their findings at seven seminars in Davos.

In the Anthropocene Review, Professor Steffen and his co-authors consider not just the strains on the planet’s resources that threaten stability, but also that section of humanity that is responsible for most of the strain.

Although the human burden of population has soared from 2.5bn to more than 7bn in one lifetime, in 2010, the scientists say, the OECD countries that are home to 18% of the world’s population accounted for 74% of global gross domestic product, so most of the human imprint on the Earth System comes from the world represented by the OECD.

This, they say, points to the profound scale of global inequality, which means that the benefits of the so-called Great Acceleration in consumption of resources are unevenly distributed, and this in turn confounds efforts to deal with the impact of this assault on the planetary machinery. Humans have always altered their environment, they concede, but now the scale of the alteration is, in its rate and magnitude, without precedent.

“Furthermore, by treating ‘humans’ as a single, monolithic whole, it ignores the fact that the Great Acceleration has, until very recently, been almost entirely driven by a small fraction of the human population, those in developed countries”, they say.

“…What surprised us was the timing. Almost all graphs show the same pattern. The most dramatic shifts have occurred since 1950”

The IGBP-Stockholm Resilience Centre co-operation first identified their 24 “indicators” of planetary change in 2004, and the latest research is a revisitation. In 2009, researchers identified nine global priorities linked to human impacts on the environment, and identified two, ­ climate change and the integrity of the biosphere, ­ that were vital to the human condition. Any alteration to either could drive the Earth System into a new state, they said.

In fact, since then, greenhouse gas emissions have continued to rise, and accordingly global average temperatures have steadily increased, along with sea levels. At the same time, habitat destruction, pollution and hunting and fishing have begun to drive species to extinction at an accelerating rate.

Almost all the charts that make up the planetary dashboard now show steep acceleration: fisheries, one of the indicators that seems to have levelled off, has probably done so only because humans may have already exhausted some of the ocean’s resources.

“It is difficult to over-estimate the scale and speed of change. In a single human lifetime humanity has become a planetary-scale geological force”, said Prof Steffen. “When we first aggregated these datasets we expected to see major changes, but what surprised us was the timing. Almost all graphs show the same pattern.

“The most dramatic shifts have occurred since 1950. We can say that 1950 was the start of the Great Acceleration. After 1950 you can see that major Earth System changes became directly linked to changes related to the global economic system. This is a new phenomenon and indicates that humanity has a new responsibility at a global level for the planet.” ­­­­–­ Climate News Network

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Climate confounds China’s efforts to ease water stress

Climate confounds China’s efforts to ease water stress

Researchers say attempts to solve China’s water crisis − already worsening through population growth, a rampant economy and climate change – are having the opposite effect.

LONDON, 14 January, 2015 − China, the world’s most populous nation, faces one of the planet’s most intractable water crises. And scientists say Beijing’s strategy for resolving the problem is simply making it worse.

A team of international researchers say that water stress is only partially mitigated by China’s current two-pronged approach: transferring water physically to regions that are short of it − for example, by the huge projects to transfer water from the south to the north of the country − and exporting the “virtual” water embodied in products traded domestically and internationally.

China needs more water for energy, food and industry, for its rising population, and for its attempts to end poverty.

But maintaining even current levels of provision is becoming increasingly difficult as climate change lives up to its dire reputation as a threat multiplier and endangers water and food supplies.

Full inventory

Researchers at the UK universities of East Anglia (UEA) and Leeds and other international institutions have compiled the first full inventory of physical water transfers and virtual water redistribution via trade between China’s provinces. Their findings are published in the Proceedings of the National Academy of Sciences.

They say the efforts to supply northern China are exacerbating water stress in its poorer water-exporting regions, with transfers of virtual water − defined as the total volume of water needed to produce and process a commodity or service − accounting for more than a third of the country’s national water supply.

Up to 65% of the supply in some provinces is reserved for virtual water redistribution, to be used for infrastructure and for producing exports.

Until China significantly improves its water-use efficiency and addresses the impact its expanding economy is having on its natural resources, the situation will continue to deteriorate, the team concludes.

“China’s current transfer programme is pouring good water after bad . . . and the provinces sharing their water are suffering greatly”

The research −  led by China’s Beijing Forestry University, UEA and Leeds universities, and the University of Maryland in the US − analyses data from 2007 and looks ahead to China’s water distribution plans in 2030. It finds that water stress is likely to become more severe in the main water-exporting provinces.

Dabo Guan, professor of climate change economics at UEA’s School of International Development, said: “China needs to shift its focus to water demand management instead of a supply-oriented approach if it is going to seriously address the overwhelming pressures on its water supplies.

“China’s current transfer programme is pouring good water after bad. The problems of water-stressed regions aren’t being alleviated, and the provinces sharing their water are suffering greatly.”

Guan and colleague Martin Tillotson, professor of water management at Leeds University, published research in 2014 showing that 75% of China’s lakes and rivers and 50% of its groundwater supplies are contaminated as a result of urban household consumption, infrastructure investment and exports.

Increased demand

Professor Tillotson said: “Even allowing for future efficiency gains in agricultural and industrial water consumption, China’s water transfers are likely to be insufficient to offset increased demand due to the effects of economic and population growth.

“A much greater focus needs to be placed on regulating or incentivising reductions in demand-led consumption.”

China aims to remain about 95% self-sufficient in food, but imports more than 60% of its oil and nearly 50% of its natural gas. Some senior officials argue that it should increase food imports so as to be able to use more of its water for producing energy.

But some of China’s neighbours and traditional suppliers are themselves facing growing problems from climate change, with several countries in south-east Asia contemplating a “shocking” future.

Some observers think that China’s growing demand for grain imports may even strain global supplies. − Climate News Network

 

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