Acid attack on algae damages ocean ecosystem

Acid attack on algae damages ocean ecosystem

Increasing acidity in the Southern Ocean is having a serious effect on the growth of a small but hugely important food source for marine life.

LONDON, 27 February, 2015 − As the planet’s oceans become more acidic, the diatoms − a major group of alga − in the Southern Ocean could grow more slowly.

Nobody expected this. And since tiny, single-celled algae are a primary food source for an entire ocean ecosystem, the discovery seems ominous.

Bioscientist Clara Hoppe and colleagues from the Alfred Wegener Institute [http://www.awi.de/en/home/]at the Helmholtz Centre for Polar and Marine Research in Bremerhaven, Germany, report in the journal New Phytologist that they tested the growth of the Antarctic diatom Chaetoceros debilis under laboratory conditions.

They used two levels of pH – which is an indicator of acidity – and they exposed their tiny volunteers to constant light and to changing light, providing both standard laboratory conditions and lighting levels that approximated to the real world.

Plant growth

In the unblinking glare of light, the diatoms responded well. Their growth levels were consistent with an assumption that more dissolved carbon dioxide – which makes the waters more acidic – would in effect fertilise plant growth.

Under conditions of changing light, however, it was a different story. The algae grew more slowly, which suggests that the oceans could become less efficient at removing carbon from the atmosphere, and perhaps less valuable as a primary food source for the creatures that teem in the Antarctic waters.

“Diatoms fulfil an important role in the Earth’s climate system,” Dr Hoppe says. “They can absorb large quantities of carbon dioxide, which they bind before ultimately transporting part of it to the depths of the ocean.

“Once there, the greenhouse gas remains naturally sequestered for centuries.”

Previous research into the steady acidification of the oceans has tended to concentrate on the consequences for coral reefs,  fisheries, and tourism, but not on the impact on plant life in the seas.

Since carbon dioxide acts as a fertiliser, higher levels dissolved in the water might stimulate more growth.

“We now know that when the light intensity constantly changes, the effect of ocean acidification reverses”

But growth depends not just on more carbon dioxide, but also on reliable sunlight. In the stormy southern seas, this is not steadily supplied.

Dr Hoppe says: “Several times a day, winds and currents transport diatoms in the Southern Ocean from the uppermost water layer to the layers below, and then back to the surface – which means that, in the course of a day, the diatoms experience alternating phases with more and with less light.”

Her co-author, marine biogeochemist Björn Rost, from the Alfred Wegener Institute, says: “Our findings show for the first time that our old assumptions most likely fall short of the mark. We now know that when the light intensity constantly changes, the effect of ocean acidification reverses.

“All of a sudden, lower pH values don’t increase growth, like studies using constant light show. Instead, they have the opposite effect.”

The implication is that, at certain intensities, the photosynthesis chain breaks down. The point at which light becomes too much light is more quickly reached in waters that are more acidic.

Like all such research, the finding has limitations. It applies to one species of single-celled creature in the waters of one ocean, and the tests were in a laboratory on a small scale, and not in a turbulent ocean rich in life. The Alfred Wegener team will continue their studies.

But in the real world, coastal communities in 15 US states could be at long-term economic risk, as ocean acidification starts to take its toll on the commercial oyster fisheries.

Julia Ekstrom, then of the Natural Resources Defense Council and now director of the Climate Adaptation Programme at the University of California, Davis, and George Waldbusser, assistant professor of ocean ecology and biogeochemistry at Oregon State University report with colleagues, in Nature Climate Change, on an unholy mix in the oceans.

Fisheries at risk

They say that a combination of rising greenhouse gas levels, more acid waters, polluted rivers, and upwelling currents put at risk mollusc fisheries from the Pacific Northwest, New England, the Mid-Atlantic states and the Gulf of Mexico – affecting the shellfish industry that is worth at least $1bn to the US.

Oyster larvae are sensitive to changes in ocean water, and more likely to die as pH levels shift towards the acidic.

But acidification is not the only source of stress, as nitrogen-rich nutrients and chemical pollutants cascade from the land into the rivers, and wash through estuaries and fish hatcheries on the coast.

Things can be done. Scientists have been looking at ways in which the industry might be able to adapt to change. But how well the oyster stock can adapt in the long term remains problematic.

“Ocean acidification has already cost the oyster industry in the Pacific Northwest nearly $110 million and has jeopardised about 3,200 jobs,” Dr Ekstrom says.

And Dr Waldbusser adds: “Without curbing carbon emissions, we will eventually run out of tools to address the short term, and we will be stuck with a much longer-term problem.” – Climate News Network

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Big cities head for water crisis as populations explode

Big cities head for water crisis as populations explode

With more than half the world’s population now in cities, scientists warn that inadequate surface water supplies will leave many at increasing risk of drought.

LONDON, 21 February, 2015 − More than 40% of the world’s great cities supplied by surface water could become vulnerable to shortages and drought by 2040, according to new research. And more than three out of 10 were already vulnerable in 2010.

Meanwhile, the vital array of satellites designed to monitor rainfall and to warn of potential flooding is reported to be coming to the end of its shelf life.

For the first time in history, more than half the world’s population is now concentrated in cities, and this proportion is predicted to increase to two-thirds. Cities grow up near plentiful water supplies − and as a population explodes, so does demand. But the flow remains much the same.

Some cities are already under drought stress. Chennai in southern India had to be supplied with tankers in 2004 and 2005, and São Paulo in Brazil is now at crisis point.

Supply analysis

Environmental scientist Julie Padowski and Steven Gorelick, director of the Global Freshwater Initiative at Stanford University in California, report in Environmental Research Letters that they analysed supplies to 70 cities in 39 countries, all of them with more than 750,000 inhabitants, and all of them reliant on surface water.

They defined vulnerability as the failure of an urban supply basin to meet demands from human, environmental and agricultural users, and they set the supply target as 4,600 litres per person per day – which factors in “virtual water”, defined as the total volume of water needed to produce and process a commodity or service.

They proposed three different kinds of measure of supply. If a city failed to meet one or two of these metrics, it was considered threatened. If it failed to meet all three, it was rated as vulnerable.

Importantly, the scientists did not factor in climate change, which is likely to make conditions worse. Instead, they simply considered current demand and supply, and then projected demand in 2040.

Of their 70 cities, they found that 25 (36%) could already be considered vulnerable by 2010. By 2040, this number had grown to 31 (44%).

The six cities that will begin to face water shortages are Dublin in Ireland, Charlotte in the US, Ouagadougou in Burkina Faso, and Guangzhou, Wuhan and Nanjing in China.

Most of the cities that are already vulnerable rely on reservoirs, and the study implies that urban planners will need to think about more reservoirs, deeper wells or desalination plants, or will have to contemplate the diversion of rivers from somewhere else.

Rainfall data

Meanwhile, they cannot rely on rainfall data because – as geological engineer Patrick Reed, professor of civil and environmental engineering at Cornell University, and colleagues report in Environmental Research Letters − the network of dedicated satellites “fails to meet operational data needs for flood management”.

Four of the 10 satellites have exceeded their design life − some by more than a decade. There are already weak spots in the network, especially in developing countries, which means that floods could take people by surprise.

Space-based instruments offer a way of monitoring rainfall and ground moisture upstream, in a way that gives authorities time to predict the moment when the rivers will start to rise and flood the cities. When four fail to deliver, the potential for catastrophe will be even worse.

So the scientists call for better international co-ordination of satellite replacement.

“It is important for us to start thinking as a globe about a serious discussion on flood adaptation and aiding affected populations to reduce their risks,” Professor Reed says. “We want to give people time to evacuate, to make better choices, and to understand their conditions.” – Climate News Network

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Sardines swim into northern waters to keep cool

Sardines swim into northern waters to keep cool

Fish species in subtropical European waters are migrating north to escape warming seas − leaving fishermen who rely on them for a living with empty nets.

LONDON, 20 February, 2015 − Several important fish species that for centuries have been part of the staple diet of people in the Mediterranean region are abandoning sub-tropical seas because the water is too warm and are heading north.

Sardines, which for generations have been the most abundant commercial fish species in Portugal, are moving away. They are now established in the North Sea, and are being caught in the Baltic – a sea that until recently was normally frozen over in the winter.

Sardines, anchovies and mackerel − three fish species that are important in the diet of many southern European and North African countries − have been studied by scientists trying to discover how climate change and warming seas are affecting their distribution.

Fishing industry

As well as the affect on the fishing industry, the abundance or disappearance of these species is crucial for many other marine species that rely on them for food.

A pioneering study, published in Global Change Biology, analysed 57,000 fish censuses conducted over 40 years, and has tracked the movement of these fish during this period.

It confirms that the continued increase in water temperature has altered the structure and functioning of marine ecosystems across the world. But it also shows that the effect has been greater in the North Atlantic, with increases of up to 1.3 ºC in the average temperature over the last 30 years.

This variation in temperature directly affects the frequency and range of pelagic fish, which live in the middle of the water column and are directly influenced by temperature, rather than habitat. It includes the sardine (Sardina pilchardus), anchovy (Engraulis encrasicolus), horse mackerel (Trachurus trachurus) and mackerel (Scomber scombrus), among others.

Sardines and other fish represent “an exceptional bioindicator to measure the direction and speed of climate change expected in the near future”

They feed off phytoplankton and zooplankton, and are themselves the staple diet of large predators, such as cetaceans, large fish and marine birds. These fish occur off the shores of many coastal countries in the world and are important sources of protein.

Scientists have known that fish were moving to new areas, but did not know whether it was in response to their main food supply plankton moving first or whether it was a simple response to changing temperatures.

The new study has developed statistical models for the North Sea area, and confirms the great importance of sea temperatures.

“Time series of zooplankton and sea surface temperature data have been included to determine the factor causing these patterns,” Ignasi Montero-Serra, lead author of the study and researcher in the department of Ecology at the University of Barcelona, explains to the Scientific Information and News Service.

To demonstrate the consequences of the warming of the seas, the research team analysed fish censuses from commercial fishing performed independently along the European continental shelf between 1965 and 2012, extracted from data provided by the International Council for the Exploration of the Sea.

The study, which is the first to be carried out on such a large timescale and area, allows for the dynamics of this species to be understood in relation to the rapid warming of the oceans that has been happening since the 1980s.

The results reveal that sardines and other fish with fast life cycles, planktonic larval stage and low habitat dependence are highly vulnerable to changes in ocean temperature, and therefore represent, Montero-Serra says, “an exceptional bioindicator to measure the direction and speed of climate change expected in the near future”.

Accelerated increase

Montero-Serra says that accelerated increase in temperature of the continental seas has resulted in sardines and anchovies − with a typically subtropical distribution − increasing their presence in the North Sea and “even venturing into the Baltic Sea”. And the presence of species with a more northern distribution, such as the herring and the sprat, has decreased.

The analysis is therefore a clear sign that species in the North Sea and Baltic Sea are “becoming subtropical”.

This is due to the pelagic fish being highly dependent on environmental temperatures at different stages of their life cycle − from reproductive migrations and egg-laying, to development and survival of larvae.

According to the researchers, the changes in such an important ecological group “will have an effect on the structure and functioning of the whole ecosystem”, although they still do not know the scale of the socio-economic and ecological repercussions. – Climate News Network

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Arid areas of US face prospect of ‘megadroughts’

Arid areas of US face prospect of ‘megadroughts’

Scientists in the US predict droughts worse than the extreme conditions believed to have played a part in ending a once-flourishing medieval culture.

LONDON, 15 February, 2015The Central Plains and Southwest region of the US face “unprecedented” droughts later this century, according to new research.

While Midwest states have experienced ever more flooding over the last 50 years, the regions already suffering from extremes of aridity are being warned to expect megadroughts worse than any conditions in the last 1,000 years.

Climate scientist Benjamin Cook, of NASA’s Goddard Institute for Space Studies, New York, and colleagues report in a new journal, Science Advances, that they looked at historical evidence, climate projections and ways of calculating soil moisture.

They found that the drought conditions of the future American west will be more severe than the hottest, most arid extended droughts of the 12th and 13th centuries, which are thought to have played a role in ending the once-flourishing Pueblo culture of the American Southwest.

Computer predictions

The growth rings of trees provided the evidence for reconstructions of what climatologists call the warm Medieval period, and the researchers matched the picture from the past with 17 different computer model predictions of the climate later in the 21st century.

The conclusions were ominous: nearly all the models predicted that the Plains and the Southwest would become drier than at any time in the last 1,000 years.

Even though winter rain and snowfall could increase in parts of California – currently in the grip of calamitous drought – in the decades to come, overall there will be lower cold season precipitation and, because of higher temperatures, ever more evaporation and ever more water demand for the surviving vegetation.

The authors conclude: “Ultimately, the consistency of our results suggests an exceptionally high risk of a multidecadal megadrought occurring over the Central Plains and Southwest regions during the late 21st century, a level of aridity exceeding even the persistent megadroughts that characterised the Medieval era.”

“I was honestly surprised at just how dry the future is likely to be”

Co-author Toby Ault, head of the Emergent Climate Risk Lab at Cornell University, warned of future megadroughts only last year. He says: “I was honestly surprised at just how dry the future is likely to be.”

But to the north, in the American Midwest, conditions have begun to change in a different way. Iman Mallakour and Gabriele Villarini, of the Department of Civil and Environmental Engineering at the University of Iowa, collected evidence from 774 stream gauges in 14 states from 1962 to 2011.

Flood events

They report in Nature Climate Change that a third of them had recorded a greater number of flood events, and only one in 10 recorded a decrease.

The pattern of increase extended from North Dakota south to Iowa and Missouri, and east to Illinois, Indiana and Ohio.

The region was hit by economically-disastrous, billion-dollar floods in 1993, 2008, 2011, 2013 and 2014. The researchers wanted to see whether flooding was really on the increase, or whether perception of greater flooding was what they called “an artefact of our relatively short collective memory”.

The result is a confirmation of perceived increase. It was not an artefact.

“It’s not that big floods are getting bigger, but that we have been experiencing a larger number of big floods,” Dr Villarini says. – 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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EU aids shoppers to steer clear of harmful palm oil

EU aids shoppers to steer clear of harmful palm oil

New food labelling rules on giving consumers in Europe more information should help to protect the world’s tropical forests and the climate.

LONDON, 6 February, 2015 A European Union decision to give consumers more information about the food they buy could mean good news for tropical countries whose forests are threatened by the expanding trade in palm oil.

Palm oil is found in 50% of supermarket products, such as soaps and shampoos, and in many sorts of food. But the EU requirement that food products containing the oil must now be labelled clearly should help to dispel doubts about the damage it can cause.

Producing the oil often involves felling virgin rainforest, reducing biodiversity and destroying the habitat of endangered species such as orangutans, elephants and tigers, and ruining the livelihoods of local people.

It also involves the release of large quantities of carbon dioxide into the atmosphere when carbon-rich tropical forests are cleared for plantations.

Short-term impact

The EU move is not expected to change things overnight. Simon Counsell, executive director of the Rainforest Foundation UK, said: “We imagine that the impact in the short term will be fairly limited, as it’s hard to see busy people scanning through a long list of ingredients on manufactured foods to see if the product contains palm oil.

“So we believe there is still very much a need for a clear and simple product guide such as ours, so that people can know to avoid altogether products that contain palm oil.”

Indonesia and Malaysia produce 85% of the global palm oil supply, and wholesale logging there is a direct threat to some of the last remaining habitats of orangutans. There are thought to be around only 60,000 surviving in the wild.

Elizabeth Clarke, business and biodiversity programme manager at the Zoological Society of London, said: “Palm oil production is vital to the economies of countries where it is grown, but it also has serious negative environmental impacts, particularly if grown unsustainably.

“We don’t have any space left to farm − we don’t benefit from anything”

“We are working with the industry to promote sustainable practices and responsible investment through our new Sustainable Palm Oil Transparency Toolkit, SPOTT.

“More is needed to reduce pressures on wildlife, ensuring a future for the remaining 300 Sumatran tigers whose habitat is at severe risk of being lost from deforestation as a result of irresponsible practices.”

New areas face threats in Africa and Latin America. In the Congo, for example, a million acres are already being cultivated for palm oil, with a further 284 million acres of pristine rainforest currently at risk. The Congo contains the world’s second largest tropical rainforest − after the Amazon − and is one of the most important wilderness areas left on Earth.

Many people living in the forests feel powerless. Chief André Sayom, head of the village of Nkollo, in Cameroon, told the Rainforest Foundation: “We don’t have any space left to farm. We don’t benefit from anything. We’ve been displaced more than once already.

Explicit statement

Life becomes very difficult when these multinationals set foot somewhere. These projects need to be looked at in the long term, and populations need to be informed and consulted”.

The new EU rules, introduced last December, require companies that use palm oil in their food products to label them with an explicit statement, rather than simply relying on vague, catch-all references to “vegetable oil”. They can also now highlight their use of certified sustainable palm oil

Unilever is one of the world’s major buyers of palm oil, purchasing around 1.5 million tonnes annually about 3% of global production. It promised that all the oil directly sourced for its European foods business would be 100% traceable and certified sustainable from the end of 2014.

Palm oil production is big business. The industry is worth $44 billion, with the world consuming 55 million tonnes in 2013 − nearly four times the 1990 total. And the World Bank expects today’s global demand to have doubled by 2020. Climate News Network

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California is left high and dry by cannabis growers

California is left high and dry by cannabis growers

As California endures its worst drought since records began, illegal marijuana plantations are being blamed for further depleting precious water resources.

MENDOCINO, 4 February, 2015 − Take a flight over the densely forested area in California’s northern coastal region and it’s not hard to spot the marijuana plantations, their bright green plants standing out in clearings in the surrounding vegetation.

But now the big-money cannabis industry is being blamed for adding to water shortage problems caused by a three-year drought that has seriously affected California’s huge agricultural sector.

Although cultivating and using marijuana is illegal under US Federal law, California state law allows marijuana growing – as long as it is for medicinal purposes.

Rules flouted

However, the rules governing who can and cannot grow pot are complex – and openly flouted by thousands of growers, both big and small-time operators.

A report by the California Department of Fish and Wildlife (CDFW) estimates that, in this northern region of the state,  marijuana growing doubled between 2009 and 2012.

Marijuana plants are extremely thirsty, consuming between five and 10 gallons of water per day, depending on the phase of their growing cycle. Officials at the CDFW say that marijuana growers are sucking up precious water resources, exacerbating water shortages and threatening fish in the area’s lakes and streams.

Marijuana growing is particularly prevalent in an area of northern California known as The Emerald Triangle, encompassing Mendocino, Humbolt and Trinity counties. Some estimates say the crop accounts for up to 40% of the region’s economy.

Officials of the CDFW say that the small, well-established marijuana plantations – run by what are described as old time hippies − are not to blame for pumping up excess water.

Illegal marijuana plantations in forest clearings. Image: US Drug Enforcement Agency

Illegal marijuana plantations in forest clearings.
Image: US Drug Enforcement Administration

It is the incomers from outside the area − part of a “green rush” into highly-profitable marijuana growing – that are mainly to blame. These growers are out to make quick profits, and care little about the environment.

Growers of various crops in California are bound by rules stipulating that no more than 10% of the flow of water courses should be diverted for crops, and that such diversions should stop altogether in late summer, when water levels are at their lowest.

The CDFW says the incomers take vast amounts of water in order to harvest their crops as fast as possible. They also use excessive quantities of fertilizer, which leach into water courses, endangering fish stocks and polluting land.

Armed gangs

Fines of up to $8,000 per day are now being imposed for water theft, although monitoring illegal activities is difficult − and, at times, dangerous. Heavily-armed gangs are often involved in the marijuana growing business, and the CDFW has warned that, as the drought continues, conflicts over water resources are likely to increase.

The Emerald Growers Association, a group that represents some of northern California’s marijuana growers, says more regulation is needed to separate the legitimate pot growers from illegal ones.

The drought in California has been going on since 2011 and is described as the worst in the state since records began in the 1850s.

Arguments continue as to whether man-made climate change or natural phenomena are causing the drought.

Although significant amounts of rain last December helped alleviate dry conditions in some parts of the state, experts say more rain is urgently needed to feed watercourses and restock severely depleted aquifers. – Climate News Network

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California rains bring little relief from harsh drought

California rains bring little relief from harsh drought

Unless substantial rain falls soon, California’s worst drought on record threatens dire consequences for the state’s massive agricultural industry.

DAVIS, CALIFORNIA, 29 January, 2015 − Doing the right thing in the environs of the University of California, Davis – one of the foremost agricultural institutions in the US – means driving a carbon efficient car. And having a lawn that’s burned dry.

California’s worst drought on record is forcing people to cut back radically on water use – and that means letting lawns die. There was considerable rainfall last month, but it was not nearly enough to replenish the badly-depleted water resources.

“If we don’t have rain in significant amounts by early March, we’ll be in dire straits,” says Professor Daniel Sumner, director of the Agricultural Issues Center at Davis.

Water restrictions

Higher than average temperatures – particularly during the winter months – have combined with a lack of rainfall to produce severe drought conditions across much of the state. Water restrictions have been brought in following the imposition of a drought emergency in January last year.

“Historically, California’s water has been stored in the snow pack in the mountains, but warmer winter temperatures have meant the pack has been melting.” Sumner says.

“The agricultural sector has made considerable advances in limiting water use, and new, more drought resistant, crops and plant varieties have been introduced, but aquifers have been pumped and they are not being replenished.

“In the past, massive projects were undertaken to distribute water round the state, but now there’s not the money available to do any more big-time plumbing work. Also, the regulations on diverting water for agriculture use are very tight – rivers can’t be pumped if it means endangering fish stocks or other wildlife.”

“California is still growing – and exporting – rice, which is a real water drinker. How crazy is that?”

Whether or not climate change is causing the drought is a matter of considerable debate. A recent report sponsored by the US government’s National Oceanic and Atmospheric Administration (NOAA) says natural oceanic and atmospheric patterns are the primary drivers behind the drought.

A high pressure ridge that has hovered over the Pacific off California’s coast for the past three years has resulted in higher temperatures and little rainfall falling across the state, the report says.

However, a separate report by climate scientists at Stanford University says the existence of the high pressure ridge, which is preventing rains falling over California, is made much more likely by ever greater accumulations of climate-changing greenhouse gas emissions in the atmosphere.

Whatever the cause of the drought, the lack of rain is doing considerable environmental and economic damage. The Public Policy Institute of California, a not-for-profit thinktank, estimates that $2.2 billion in agricultural revenues and more than 17,000 jobs have been lost as a result of the drought.

Severely depleted

Thousands of acres of woodland have been lost due to wildfires, while fisheries experts are concerned that severely depleted streams and rivers could lead to the disappearance of fish species in the area, such as coho salmon and steelhead trout.

The drought is not limited to California. Adjacent states are also affected, and over the US border to the south, in Mexico’s Chihuahua state, crops have been devastated and 400,000 cattle have died.

Frank Green, a vineyard owner in the hills of Mendocino County, northern California, says: “The vines are pretty robust and, despite the drought, our wines have been some of the best ever over the past two years.

“But there’s no doubt we need a lot more rain, and plenty more could be done on saving and harvesting water. Farmers have cut back on growing water-hungry crops like cotton, but California is still growing – and exporting – rice, which is a real water drinker. How crazy is that?” – 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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