Wednesday, April 30, 2014

North Sea 'Atlantis' hit by tsunami

A prehistoric 'Atlantis' in the North Sea may have been abandoned after being hit by a 5m tsunami 8,200 years ago.

The wave was generated by a catastrophic subsea landslide off the coast of Norway.

Analysis suggests the tsunami over-ran Doggerland, a low-lying landmass that has since vanished beneath the waves.

'It was abandoned by Mesolithic tribes about 8,200 years ago, which is when the Storegga slide happened,' said Dr Jon Hill from Imperial College London.

'Start Quote

The impact... would have been massive - comparable to the Japanese tsunami of 2011'

End Quote Dr Jon Hill Imperial College London

The wave could have wiped out the last people to occupy this island.

The research has been submitted to the journal Ocean Modelling and is being presented at the European Geosciences Union General Assembly in Vienna this week.

Dr Hill and his Imperial-based colleagues Gareth Collins, Alexandros Avdis, Stephan Kramer and Matthew Piggott used computer simulations to explore the likely effects of the Norwegian landslide.

He told BBC News: 'We were the first ever group to model the Storegga tsunami with Doggerland in place. Previous studies have used the modern bathymetry (ocean depth).'

As such, the study gives the most detailed insight yet into the likely impacts of the huge landslip and its associated tsunami wave on this lost landmass.

During the last Ice Age, sea levels were much lower; at its maximum extent Doggerland connected Britain to mainland Europe.

'Start Quote

I think they are probably right, because the tsunami would have been a catastrophic event'

End Quote Prof Vince Gaffney University of Birmingham

Amazingly, it was possible for human hunters to walk from what is now northern Germany across to East Anglia.

But from 20,000 years ago, sea levels began to rise, gradually flooding the vast landscape.

By around 10,000 years ago, the area would still have been one of the richest areas for hunting, fishing and fowling (bird catching) in Europe.

A large freshwater basin occupied the centre of Doggerland, fed by the Thames river from the west, and by the Rhine in the east. Its lagoons, marshes and mudflats would have been a haven for wildlife.

'In Mesolithic times, this was paradise,' explained Bernhard Weninger, from the University of Cologne in Germany, who was not involved with the present study.

But 2,000 years later, Doggerland had become a low-lying, marshy island covering an area about the size of Wales.

The nets of North Sea fishing boats have pulled up a wealth of prehistoric bones belonging to the animals that once roamed this prehistoric 'Garden of Eden'.

But the waters have also given up a smaller cache of ancient human remains and artefacts from which scientists have been able to obtain radiocarbon dates.

And they show that none of these relics of human habitation on Doggerland occur later than the time of the tsunami.

The Storegga slide involved the collapse of some 3,000 cubic km of sediment.

'If you took that sediment and laid it over Scotland, it would cover it to a depth of 8m,' said Dr Hill.

Given that the majority of Doggerland was by this time less than 5m in height, it would have experienced widespread flooding.

'It is therefore plausible that the Storegga slide was indeed the cause of the abandonment of Doggerland in the Mesolithic,' the team writes in their Ocean Modelling paper.

Dr Hill told BBC News: 'The impact on anyone who was living on Doggerland at the time would have been massive - comparable to the Japanese tsunami of 2011.'

But Bernhard Weninger suspects that Doggerland had already been vacated by the time of the Storegga slide.

'There may have been a few people coming with boats to fish, but I doubt it was continuously settled,' he explained.

'I think it was so wet by this time that the good days of Doggerland were already gone.'

Prof Vince Gaffney, an archaeologist at the University of Birmingham, told BBC News: 'I think they (the researchers) are probably right, because the tsunami would have been a catastrophic event.'

But he stressed that the archaeological record was still sparse, and at least two axes dating to the Neolithic period (after the Storegga tsunami) had been retrieved from the North Sea.

It is possible these were dropped from a boat - accidentally or as a ritual offering - but it is also unclear precisely when Doggerland finally succumbed to the waves.

'Even after major volcanic eruptions, people go back, sometimes because they can't afford not to and also because the resources are there,' said Prof Gaffney, who has authored a book, Europe's Lost World: The Rediscovery of Doggerland.

The tsunami would also have affected what is now Scotland and the eastern coast of England, as well as the northern coast of continental Europe.

The wave that hit the north-east coast of Scotland is estimated to have been some 14m high, though it is unclear whether this area was inhabited at the time.

But waves measuring some 5m in height would have hit the eastern coast of England, and there is good evidence humans were in this area 8,000 years ago.

Much of this region would also have been low-lying, suggesting the impact on Mesolithic people who depended substantially on coastal resources such as shellfish, would have been significant here, too.

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Warming boosts UK flooding risk

A citizen science project suggests climate change really has increased the risk of flooding in the UK.

The issue has been highlighted by the recent floods, amid a January that saw double the normal monthly rainfall in parts of England.

Prof Myles Allen presented evidence of a link between floods and climate change at the European Geoscience Union meeting in Vienna.

It indicates climate change is increasing the risk of extreme weather.

It also suggests that insurance costs are likely to grow.

'Start Quote

The risk [of extreme weather] has shown movement in one direction only - to greater risk'

End Quote Prof Thomas Stocker University of Bern

Met Office data showed that the prolonged and heavy rain was an extreme outlier in the context of their records of 20th Century rainfall. But scientists can go back further to judge just how extreme this wet winter was.

It turns out that it was the wettest January and wettest winter in the world's longest daily rainfall record, collected in Oxford from 1767 to the present day.

At the time, many people suspected a link to climate change, but any such claim has been treated with caution.

Plenty of studies assessed in the most recent Intergovernmental Panel on Climate Change (IPCC) report suggest that extreme weather events should be expected in a warming world, but even there, the assessment was that the link could only be made modestly, with 'medium' certainty.

In just two months following the flooding, perhaps spurred on by the local impacts on the Thames Valley, the team at the University of Oxford has carried out an 'attribution experiment' to attempt to test what, if any, links can be made between the world's changing climate and local events like the UK winter floods.

Dr Nathalie Schaller and Dr Friederike Otto, together with others from Oxford's Environmental Change Institute, compared rainfall results from climate models based on the current global (warmed) climate with results predicted for the world we would be in today had fossil fuels never been burned.

They had to run 12,842 simulations using today's actual climate with 25,893 computer calculations of a non-warmed world to be able to get enough data to draw out the differences.

The data analysed through a citizen science project which is still active, at, the world's largest climate modelling experiment.

Their results showed a small, but significant, difference between the two scenarios. They reveal that the probability of extremely wet English winters has increased with global warming.

Climate change means that the chance of extreme weather like the January 2014 floods has increased by a small, but measurable, amount.

The group's results imply that any weather fluctuation that would previously have been thought of as a 'one in 100 year' event has now risen in probability to one in 80 years, due to climate change.

Speaking about the results at the European Geosciences Union (EGU) annual meeting, a gathering of 12,000 researchers here in Vienna, Prof Allen, from the University of Oxford, pointed out that this is the first quantitative study of the role of climate change on the 2014 floods.

Commenting on the results, Professor Thomas Stocker of the University of Bern, Switzerland (and Co-Chair of Working Group 1 of the IPCC) said: 'The risk [of extreme weather] has increased. It has shown movement in one direction only - to greater risk.'

Quoted in a press release, Dr Otto stated: 'Past greenhouse gas emissions and other forms of pollution have 'loaded the weather dice', so the probability of the south of England experiencing extremely wet winters again has slightly increased.

'We are working with collaborators, such as at the Centre for Ecology and Hydrology, to explore the implications of our results for river flows, flooding, and ultimately property damage.'

Insurance companies are very interested to understand how weather is changing compared with historic records, which is exactly the type of information that the Prof Allen's team have obtained.

Dr Schaller notes that the results must be understood in context, and are specific to the UK in winter. 'It all depends on the region and season considered, climate change might increase, decrease or have no effect at all on flood events', she told the BBC.

'Hirabayashi and co-workers, for example, showed that floods are expected to decrease with climate change in Central Europe. So our results are only valid for the southern UK and for winter months.'

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Government backs UK spaceport plan

The government has backed plans for a four-fold expansion of the UK space industry to £40bn by 2030.

It is also considering developing the necessary legal framework to permit a spaceport to be set up in the UK.

It is hoped that this might see the growth of new space tourism companies to start operating services in Britain.

There will also be a simplification of regulations and greater coherence to spur the growth of new space firms.

The government made the announcements in response to an industry report published last year called Space Innovations and Growth Strategy Action Plan, which was published last year.

'Start Quote

The space sector has the potential to propel UK growth'

End Quote David Willetts Science Minister

The industry has been growing at 7% each year during the recession. Space technology requires ultra-high precision engineering which is a UK strength with a background in defence technology companies.

This, coupled with British strength in space science, makes it ideally placed to take advantage of the projected rapid expansion in low-cost satellite launches and space tourism. Space is already a multi-billion-pound industry.

The science minister has been a supporter of the UK space industry and has fostered closer links with the European Space Agency (Esa).

He was closely involved in negotiating the selection of Esa's first UK astronaut, Tim Peake.

Major Peake will be going into space next year to conduct experiments on the International Space Station (ISS).

Mr Willetts said that the space sector could 'propel' UK growth.

'Start Quote

The government is working shoulder-to-shoulder with industry to exploit the full potential of the space sector and inspire the next generation'

End Quote Dr David Parker Chief executive, UK Space Agency

'Space industries already support 95,000 full time jobs and generate £9.1 billion for the economy each year, and our response to the Growth Action Plan shows our commitment to secure its future growth and realise ambitions to develop a viable UK space port for commercial space flight,' he explained.

Dr David Parker, chief executive at the UK Space Agency said that government is working 'shoulder-to-shoulder with industry to exploit the full potential of the space sector to grow the economy, deliver more efficient public services and inspire the next generation'.

'At the UK Space Agency, we are particularly focusing on helping the rest of government make best use of the huge increase in real-time data from the Galileo and Sentinel satellites, looking at exciting opportunities such as a UK spaceport, and leading an export drive for UK space products and services.

'Our vision is to make the UK the most attractive location for space businesses to set up and prosper - and I'm convinced we are on our way.'

The chief executive of Surrey Satellite Technology, Dr Matt Perkins, told BBC News that 'the space sector has huge potential and I believe the strong government endorsement of this strategy provides a pathway to achieving increased economic benefit for the UK and growth for SSTL.'

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Drug resistance 'global threat'

Resistance to antibiotics poses a 'major global threat' to public health, says a new report by the World Health Organization (WHO).

It analysed data from 114 countries and said resistance was happening now 'in every region of the world'.

It described a 'post-antibiotic era', where people die from simple infections that have been treatable for decades.

There were likely to be 'devastating' implications unless 'significant' action was taken urgently, it added.

The report focused on seven different bacteria responsible for common serious diseases such as pneumonia, diarrhoea and blood infections.

It suggested two key antibiotics no longer work in more than half of people being treated in some countries.

'Start Quote

What we urgently need is a solid global plan of action which provides for the rational use of antibiotics'

End Quote Dr Jennifer Cohn Medecins sans Frontiers

One of them - carbapenem - is a so-called 'last-resort' drug used to treat people with life-threatening infections such as pneumonia, bloodstream infections, and infections in newborns, caused by the bacteria K.pneumoniae.

Bacteria naturally mutate to eventually become immune to antibiotics, but the misuse of these drugs - such as doctors over-prescribing them and patients failing to finish courses - means it is happening much faster than expected.

The WHO says more new antibiotics need to be developed, while governments and individuals should take steps to slow this process.

In its report, it said resistance to antibiotics for E.coli urinary tract infections had increased from 'virtually zero' in the 1980s to being ineffective in more than half of cases today.

In some countries, it said, resistance to antibiotics used to treat the bacteria 'would not work in more than half of people treated'.

Gonorrhoea treatment 'failure'

Dr Keiji Fukuda, assistant director-general at WHO, said: 'Without urgent, coordinated action by many stakeholders, the world is headed for a post-antibiotic era, in which common infections and minor injuries which have been treatable for decades can once again kill.'

He said effective antibiotics had been one of the 'pillars' to help people live longer, healthier lives, and benefit from modern medicine.

'Unless we take significant actions to improve efforts to prevent infections and also change how we produce, prescribe and use antibiotics, the world will lose more and more of these global public health goods and the implications will be devastating,' Dr Fukuda added.

The report also found last-resort treatment for gonorrhoea, a sexually-transmitted infection which can cause infertility, had 'failed' in the UK.

It was the same in Austria, Australia, Canada, France, Japan, Norway, South Africa, Slovenia and Sweden, it said.

More than a million people are infected with gonorrhoea across the world every day, the organisation said.

'Wake-up call'

The report called for better hygiene, access to clean water, infection control in healthcare facilities, and vaccination to reduce the need for antibiotics.

Last year, the chief medical officer for England, Prof Dame Sally Davies, said the rise in drug-resistant infections was comparable to the threat of global warming.

Dr Jennifer Cohn, medical director of Medecins sans Frontiers' Access Campaign, said: 'We see horrendous rates of antibiotic resistance wherever we look in our field operations, including children admitted to nutritional centres in Niger, and people in our surgical and trauma units in Syria.

'Ultimately, WHO's report should be a wake-up call to governments to introduce incentives for industry to develop new, affordable antibiotics that do not rely patents and high prices and are adapted to the needs of developing countries.'

She added: 'What we urgently need is a solid global plan of action which provides for the rational use of antibiotics so quality-assured antibiotics reach those who need them, but are not overused or priced beyond reach.'

Professor Nigel Brown, president of the UK Society for General Microbiology, said it was vital microbiologists and other researchers worked together to develop new approaches to tackle antimicrobial resistance.

'These approaches will include new antibiotics, but should also include studies to develop new rapid-diagnostic devices, fundamental research to understand how microbes become resistant to drugs, and how human behaviour influences the spread of resistance.'

Earth's last warm phase probed

Scientists now have a fuller picture of what happened at the poles during the last warm phase on Earth.

Known as the Eemian, this time period extended from roughly 129,000 years ago to about 116,000 years before present.

The poles were known to have been a few degrees warmer than they are today.

But by pulling together more than 40 ice core and marine sediment records, researchers, led by the British Antarctic Survey (BAS), have obtained the most comprehensive assessment yet.

'Start Quote

These new cores will allow us to see the climate history of the Baltic in unprecedented detail'

End Quote Dr Thomas Andren International Ocean Discovery Program

It confirms that the Antarctic emerged from Ice Age conditions first. The Northern Hemisphere followed.

'Interglacial conditions, warm conditions, were in place earlier in the Southern Hemisphere than in the Northern Hemisphere,' explained Dr Emilie Capron from BAS.

'Eventually, the Northern Hemisphere catches up and then both poles are warmer than they are today.

'It's something we knew looking at a few records, but now we have more records showing exactly the same pattern,' she told BBC News.

The researcher was speaking here in Vienna at the European Geosciences Union General Assembly.

The data synthesis has been completed as part of the Past4Future project, an EU-funded initiative that seeks clues about what will happen to the Earth's climate in the decades ahead from an understanding of its past behaviour.

Scientists will now use the information to test their computer models.

If their simulations can reproduce the variation in temperatures across the land and ocean surfaces during the Eemian there will be greater confidence in the models as they look forward in time.

This has already been done for one model, 'and its simulations are on the right track,' confirms Dr Capron.

For her analysis, the BAS researcher combined five ice cores and 39 marine sediment records.

These can be used to infer past temperatures.

By studying the ratio of light to heavy molecules of water in the layers of the ice cores, for example, it is possible to gauge the likely precipitation conditions, and therefore the prevailing temperatures, during the ancient snowfalls on Antarctica and Greenland which formed them.

And something similar can be done using the mud layers of marine sediments.

These contain the skeletons of microscopic organisms called foraminifera, and the chemistry of their hard parts is heavily influenced by the temperature of the surface waters in which they swam.

'But having the temperatures is not enough,' explained Dr Capron.

'If you are going to compare the climate from one place to another, you need a common chronology for all the different records. And this was the great challenge in this study - to try to transfer all the palaeoclimatic records on to just one time chronology, because we are working beyond the time where we can use radiocarbon dating.'

One way to line up these types of records is to look for distinctive markers such as ash layers from major volcanic eruptions.

One set of marine sediment records that came too late to be included in the study is the newly-retrieved cores that were drilled from the Baltic Sea at the end of last year.

Under the International Ocean Discovery Program, scientists took cores from seven locations that trace the history of the Baltic Sea back in time from the present, all the way to, and through, the Eemian.

Preliminary study of these cores reveals extremely fine layers that should throw up fascinating new insights on the climate history of the region.

'The sediments of the Baltic basin provide a link between the continental and marine records,' Dr Thomas Andren, the program's co-chief scientist, reported here at the EGU meeting.

'The Baltic is complicated because it reflects both the inputs of freshwater precipitation over land and also the inflow of marine water. These new cores will allow us to pull apart these signals, to see the climate history of the Baltic in unprecedented detail.'

Emilie Capron's work, which has been submitted for publication in a science journal, was also conducted under the UK iGlass programme. and follow me on Twitter: @BBCAmos

'Lab volcano' gives lightning clues

Don't do this at home. Corrado Cimarelli makes his own volcanoes that spout ash vertically at hundreds of metres a second.

The Italian is studying the awesome sight of lightning that is often observed in eruption plumes.

His 'lab volcano' allows him to recreate and study the processes that give rise to the necessary electrical conditions.

The hope eventually is to learn something about the nature of volcanoes purely from their lightning behaviour.

'Start Quote

That's the beauty of these experiments... things that are unconstrainable in nature can be constrained in the lab'

End Quote Dr Corrado Cimarelli Ludwig Maximilian University of Munich

'The lightning can tell us a lot about the structure of the eruption plume and the ash particle sizes within it,' Dr Cimarelli told BBC News.

Such information could give an indication of whether a particular eruption was likely to pose a risk to aviation, he added.

The Ludwig Maximilian University of Munich researcher was speaking here in Vienna at the European Geosciences Union General Assembly.

His lab volcano is no mountain; the vent is only about 3cm wide. But it is able to reproduce the conditions that trigger volcano lightning very successfully.

The set-up is essentially a hot, pressurised metal tube from which real volcano ash particles (from Popocatepetl in Mexico) are accelerated at high speed.

Slow-motion video captures mini-lighting strikes dancing around the exhaust jet.

To get discharges in a real volcano, there needs to be a large electrical potential between different regions of the eruption cloud.

Ash particles can be charged by fracturing them and by rubbing them together.

If the charges are big enough and are located in the right places in the plume, a bolt can jump from one location to another.

It is clear from the experiments that particle size is a critical factor. The smaller the particles, the higher the number of bolts.

'That's the beauty of these experiments,' said Dr Cimarelli.

'Things that are unconstrainable in nature can be constrained in the lab. And that's what we did. We changed systematically the sizes of the material we were using and we noticed that if we decreased the grain size of the ash, we produced more flashes.'

Dr Cimarelli's team is now taking the lessons learned out into the field to study lighting at Sakurajima volcano in Japan. It is the type of volcano that produces regular, spectacular flashes.

The scientists want to test the idea that you could extrapolate ash size from the frequency of lightning events.

'The size of the particles determines the time of residence in the atmosphere and the smaller they are, the longer they stay up to be carried by the winds,' said Dr Cimarelli.

'This means, of course, that if you have smaller particles, those particles can be carried long distances. And this is bad news for aviation, which we all know from the Eyjafjallajokull eruption in 2010.' and follow me on Twitter: @BBCAmos

Pre-pregnancy diet 'affects genes'

A mother's diet around the time of conception can permanently influence her baby's DNA, research suggests.

Animal experiments show diet in pregnancy can switch genes on or off, but this is the first human evidence.

The research followed women in rural Gambia, where seasonal climate leads to big differences in diet between rainy and dry periods.

It emphasises the need for a well-balanced diet before conception and in pregnancy, says a UK/US team.

'Start Quote

This research is showing that a Mom's nutrition can leave permanent marks on her child's genome on all the cells of the body'

End Quote Dr Robert Waterland Baylor College of Medicine

Scientists followed 84 pregnant women who conceived at the peak of the rainy season, and about the same number who conceived at the peak of the dry season.

Nutrient levels were measured in blood samples taken from the women; while the DNA of their babies was analysed two to eight months after birth.

Lead scientist Dr Branwen Hennig, from the London School of Hygiene & Tropical Medicine, said it was the first demonstration in humans that a mother's nutrition at the time of conception can change how her child's genes will be interpreted for life.

She told BBC News: 'Our results have shown that maternal nutrition pre-conception and in early pregnancy is important and may have implications for health outcomes of the next generation.

'Women should have a well-balanced food diet prior to conception and during pregnancy.'

Epigenetic effects

Experiments in mice show diet during pregnancy can have a life-long impact on the genes of offspring.

For instance, the coat colour of a mouse is influenced by its mother's diet.

These are known as 'epigenetic effects' (modifications to DNA that turn genes on and off).

One such modification involves attaching chemicals called methyl groups to DNA.

Infants from rainy season conceptions had consistently higher rates of methylation in all six genes studied, the researchers found.

These were linked to various levels of nutrients in the mother's blood.

But it is not yet known what the genes do, and what effect the process might have.

Genes 'unknown'

Co-researcher Dr Rob Waterland of Baylor College of Medicine in Houston said the findings, published in Nature Communications, were a proof in principle that a mother's diet can have epigenetic effects.

The research was showing that a mother's nutrition 'can leave permanent marks on her child's genome on all the cells of the body', he told BBC News.

Co-author Andrew Prentice, professor of international nutrition at the London School of Hygiene and Tropical Medicine, added: 'Our ultimate goal is to define an optimal diet for mothers-to-be that would prevent defects in the methylation process.'

Tuesday, April 29, 2014

Mars rover starts drilling again

The US space agency's Curiosity Mars rover has drilled another hole on the Red Planet.

It is almost a year since the robot last turned the power tool in the ground.

The vehicle has since travelled more than 5km (three miles) as it heads towards the mission's primary target - the foothills of the huge mountain that dominates Mars' Gale crater.

The rock drill was spun at a scientific waypoint known as 'The Kimberley'.

New pictures sent back to Earth on Wednesday, taken by the rover's Mahli 'hand lens', show a sharply defined hole surrounded by a pile of grey powder.

Before turning the tool, the robot had been commanded to examine several rock targets with all its survey instruments.

Scientists and engineers must now assess the qualities of the powder produced. If past practice is followed, this will have been a test.

Assuming it has gone satisfactorily, the rover will then acquire a second drill sample for ingesting in the robot's on-board laboratories.

Curiosity last used its drill in May last year in a small depression not far from its August 2012 landing site.

The samples pulled up from mudstones at the bottom of this shallow bowl contained evidence of an ancient lake.

From the rock chemistry, scientists were able to determine the type of environment that existed in Gale Crater billions of years ago.

The researchers said the conditions would have allowed micro-organisms to flourish had they been present.

Volcano eruptions have deep origins

Hawaiian volcanoes sometimes erupt as gentle flows of lava, but other times produce spectacular lava fountains.

New data from centuries-worth of eruptions suggest that the differences reflect fluctuations deep in the Earth.

Reporting in the journal Nature Geoscience, scientists considered how magma rich in volatile elements rises rapidly and erupts as high fountains.

Historical eruptions follow variations in the chemistry of Earth's deep mantle, they report.

'Start Quote

This work is the first to show a link between the nature of the volcanic melts in Earth's mantle and surface eruption styles'

End Quote Dr Marie Edmonds Cambridge University

If you travel to Tokyo, Mexico City, Seattle or Naples, all cities sitting 'under the volcano', a short journey out of town will take you to the slopes of a dormant monster.

Understanding the hows and whys of volcanic eruptions is crucial if these types of geohazard are to be properly assessed.

History suggests that the consequences of huge volcanic explosions may extend from local disaster to global catastrophe.

Spectacular shows

We learned in recent years how volcanic ash can disrupt holiday flights and cause short-lived misery. But evidence from the deep geological past implies that volcanic activity could be linked to mass extinctions, or at least significant global environmental change.

A team of volcano experts from Cambridge University and Hawaii have looked at the rocks erupted from the ocean island volcano of Kilauea, Hawaii, in 25 historical eruptions that have occurred over the last 600 years.

Kilauea is active, fed by magma from deep beneath Earth's rocky crust in a region called the mantle.

Sometimes the volcano erupts gently, with dribbles of lava running down the mountain's flanks, while other times she throws fountains of lava high into the sky, or produces curtains of fiery rock in a spectacular show.

Even the gentle lava flows pose problems for local residents, however. Just this week the Hawaiian Volcano Observatory (HVO) reported on a river of lava that is slowly flowing from Kilauea volcano's east rift zone towards the community of Puna.

Up to now, the assumption has been that the differences in volcanic eruption style can be attributed to differences in how quickly the molten rock reaches the surface, or whether the gas it contains can escape gently ahead of the magma on its ascent. But new evidence suggests that what controls these eruptions sits deeper still.

By measuring the chemistry of the original molten rock associated with each eruption, now preserved as glassy blobs in the volcanic mineral grains, the scientists found that energetic eruptions and gentler 'effusive' eruptions seem to have come from areas of the mantle with subtly different chemistries.

Describing their results, lead investigator Dr Marie Edmonds of Cambridge University told BBC News: 'The chemistry of the primitive melts feeding the explosive eruptions appears statistically different to those feeding effusive eruptions.

'We think that these primitive melts may saturate with gases and grow their bubbles deep in the system, accelerate towards the surface to a greater degree and bypass the summit magma chamber, erupting more explosively at the surface.

'This work is the first to show a link between the nature of the melts produced in Earth's mantle, and variations in surface eruption styles. It has important implications for volcano monitoring and hazard assessment.'

The data suggest that the changes in eruption reflect subtle local variations in the chemistry of Earth's mantle occurring over decades to centuries.

The team believe that a better understanding of these variations will improve volcanic hazard assessment and perhaps land use planning and risk management over similar timescales.

Megacities contend with sinking land

Subsiding land is a bigger immediate problem for the world's coastal cities than sea level rise, say scientists.

In some parts of the globe, the ground is going down 10 times faster than the water is rising, with the causes very often being driven by human activity.

Decades of ground water extraction saw Tokyo descend two metres before the practice was stopped.

Speaking at the European Geosciences Union General Assembly, researchers said other cities must following suit.

Gilles Erkens from the Deltares Research Institute, in Utrecht, in the Netherlands, said parts of Jakarta, Ho Chi Minh City, Bangkok and numerous other coastal urban settlements would sink below sea level unless action was taken.

His group's assessment of those cities found them to be in various stages of dealing with their problems, but also identified best practice that could be shared.

'Land subsidence and sea level rise are both happening, and they are both contributing to the same problem - larger and longer floods, and bigger inundation depth of floods,' Dr Erkens told BBC News.

'The most rigorous solution and the best one is to stop pumping groundwater for drinking water, but then of course you need a new source of drinking water for these cities. But Tokyo did that and subsidence more or less stopped, and in Venice, too, they have done that.'

The famous City of Water in north-east Italy experienced major subsidence in the last century due to the constant extraction of water from below ground.

When that was halted, subsequent studies in the 2000s suggested the major decline had been arrested.

Pietro Teatini's research indicates that significant instances of descent were now restricted to particular locations, and practices: 'When some people restore their buildings, for example, they load them, and they can go down significantly by up to 5mm in a year.' How far they descended would depend on the type and compaction of soils underneath those buildings, the University of Padova researcher added.

Like all cities, Venice has to deal with natural subsidence as well.

Large-scale geological processes are pushing the ground on which the city sits down and under Italy's Apennine Mountains. This of itself probably accounts for a subsidence of about 1mm each year. But on the whole, human-driven change has a greater magnitude than natural subsidence.

Scientists now have a very powerful tool to assess these issues. It is called Interferometric Synthetic Aperture Radar. By overlaying repeat satellite images of a specific location, it is possible to discern millimetric deformation of the ground.

Archives of this imagery extend back into the 1990s, allowing long time-series of change to be assessed.

The European Space Agency has just launched the Sentinel-1a radar satellite, which is expected to be a boon to this type of study. and follow me on Twitter: @BBCAmos

Monday, April 28, 2014

Scientists study Swiss lake tsunamis

How do you prepare for tsunamis that come only every 1,000 years or so?

This is the issue Swiss geoscientists are wrestling with as they study the country's big lakes.

Some of these water bodies around the Alps have been known to experience huge waves that were driven by sub-surface landslides, which were themselves triggered by earthquakes.

The researchers' work indicates such hazards still exist but the likelihood of future events is very small.

'These incidents happen much less frequently than flooding or avalanches, which makes tsunamis a very hard-to-grasp hazard that is simply not in the minds of the population. But as geoscientists we have a duty to look at the problem and to let people know the risks,' explained Prof Flavio Anselmetti from the University of Bern.

He was speaking here in Vienna at the European Geosciences Union General Assembly.

The professor recalled the estimated Magnitude 5.9 quake in the Alps region in AD 1601 that prompted sediment on sub-surface slopes in Lake Lucerne to slide down on to the lake basin floor.

As the muds descended, they alternately made the water column above slump and then rise, setting off a sequence of waves that inundated coastal communities.

The chronicles from the time talk of mountains of water appearing in the middle of the lake, and of water reaching inland to a distance of 1,000 steps or three gunshots. This would be about a half to one kilometre.

Floating debris was described also to have been caught in trees to the height of two halberds. The weapon famously associated with Medieval Swiss soldiers features an axe on the end of a long staff and measures about 2m.

Prof Anselmetti and colleagues have studied the collapsed sediments in the lake, and have simulated the likely tsunami waves they generated.

They can show how the waves move and how they can be reflected off opposite shores in a complex pattern.

'Those slopes that were triggered in 1601 - they will need quite a while to be 'recharged',' explained Prof Anselmetti.

'But there are other areas where we can see metres of soft sediment that are more or less ready to be released, so to speak. And we do geotechnical analysis in order to quantify just how much we need to shake these slopes in order to make them unstable.

'So, actually, we can predict to a certain degree what sort of earthquake is required to trigger which kinds of slopes, and because our numerical codes then allow us to calculate the resulting tsunami wave, we are somehow able to say which areas will be mostly affected.'

The major qualification here is that the frequency of quakes of sufficient magnitude occurring in the region is small.

Those same collapsed sediments in Lake Lucerne can be used like ancient seismograms to time the reoccurrence of big tremors.

This reveals there were six destabilisation events in the past 15,000 years similar in size to 1601.

A recurrence interval of 1,000 to 2,000 years is too long for one generation of people to pay much attention to, concedes Prof Anselmetti. Nonetheless, the risks need to be quantified, he says.

'Somehow it is our duty as geologists to remind society that this is natural hazard - we may have tsunami waves, they occur rarely, but it is a natural hazard they should be aware of without making of course too much of a panic.'

The summation of the research is being presented to the EGU meeting this week by the University of Bern's Michael Hilbe. and follow me on Twitter: @BBCAmos

DNA fingerprint for legendary tree

Legend has it that Hippocrates, the ancient Greek 'father' of medicine, taught his students under a tree on the island of Kos.

More than 25 centuries later, experts in the US have produced the first DNA barcode of the Oriental plane that is believed to be its descendant.

The original tree died centuries ago but the Greeks believe one of its descendents grows in the same place.

'In terms of symbolism this is huge,' said team member Amy Driskell.

Dr Driskell manages the Smithsonian's Laboratories of Analytical Biology, which carried out the barcoding.

Hippocrates invented the idea that people with the same disease exhibit similar symptoms which produced similar outcomes.

His book, Prognosis, was the first to compare cases in an organised study and remains the basis of the theory of modern medical diagnosis.

Cuttings from this 500-year-old tree, a member of the Oriental plane tree species, have been presented as gifts to major medical institutions all over the world.

One was planted at the National Library of Medicine near Washington DC (part of the National Institutes of Health - NIH), when the building opened in 1962 - and the DNA barcode was created from this tree.

Barcodes are fragments of DNA that are unique to individual species and serve as their genetic fingerprint. More than 200,000 have been collected as part of the DNA Barcode of Life Project which aims to create a database of barcodes from every species on Earth.

Each barcode comes from a specific specimen that is stored at a museum or similar permanent repository that provides access to research. The raw DNA data is also publicly available.

'The idea of a barcode is that you can go back and find the organism that it came from. So the original can be consulted a hundred years from now,' says Dr Driskell.

The Hippocrates Tree at the National Library of Medicine has become the source of the first barcode for the Oriental plane tree species.

'I'm sure that Hippocrates would have been fascinated by the DNA Barcode Project and I think he would have been very excited about how DNA comparison and other modern methods are being used to better understand and ultimately treat human disease,' said Dr David Lipman, director of the National Library of Medicine's National Center for Biotechnology Information.

But it very nearly didn't happen. In 1990 NIH chief landscape architect Lynn Mueller noticed the tree's health was declining and by 2003 it was almost dead. He began a desperate quest to find ways to clone the tree and save one of the few tangible links to Hippocrates in the US.

Nurseries around the country were given cuttings, but all failed to take. Eventually he contacted the Archangel Ancient Tree Archive in Michigan where experts managed to produce several clones.

'A new growth clipping is taken from the plant and the end is submerged in different rooting hormones to encourage new cell growth,' said Mr Mueller.

'They're put into a special soil which is sterilised - and we have our new trees.'

Last year the National Library of Medicine tree was pronounced dead and felled. Last week (April 25), one of its clones was dedicated and planted in the same spot.

'I've been worried for 25 years, no question. And I got more worried as the nurseries and propagators I contacted were failing,' says Mr Mueller. 'It was only the Archangel Ancient Tree Archive with their special techniques - they were the ones to save the tree for us.'

The DNA used to produce the barcode was extracted from the dead tree's wood, just under the bark. Genetic material extracted from a dead plant can sometimes be harder to find or inferior to DNA taken from a living species.

'It's probably not the best DNA in the world - it might be hard to make a genome from - but it was perfectly fine for what we needed to do,' says Dr Driskell.

'This is all about the study of life,' said Dr Constantine Stratakis, scientific director of intramural research at the National Institute of Child Health and Human Development.

'Most of the patients treated here have rare diseases and the discovery of what causes disease comes from studying DNA. The way DNA works is the same, whether you are a plant, a small organism, a human being or any other animal.'

But there are some questions DNA can't answer. Did Hippocrates really teach students under a tree, and if he did, is the Hippocrates Tree at the National Library of Medicine really its descendent?

'I can't think of a way that exists right now that DNA could prove this one way or another,' said Dr Driskell.

'The DNA tells me nothing more than that this tree belongs to this particular species (the Oriental plane tree).'

And so the legend of the Hippocrates Tree lives on. Science can't prove it existed, but it can't dispel the myth either.

Algarve golf courses' growing thirst

The Algarve has some of the best and most popular golf courses in Europe, but they need a huge amount of water to stay in tip-top shape.

And now scientists have used satellite and weather station data to calculate just how much the greens and fairways of southern Portugal are consuming.

The study shows the Algarve's 40 courses are being irrigated with some 18 million cu m of water a year.

It is the equivalent of them receiving about 500,000mm of rain.

'The greenkeepers understand the challenges of using so much water and they are introducing efficiency strategies,' Prof Celestina Pedras from the University of the Algarve in Faro told BBC News.

She was presenting her work here in Vienna at the European Geosciences Union (EGU) General Assembly meeting.

Golf has boomed in the region since the 1980s when there were just a handful of courses.

The constant sunshine, the proximity to the beach, and the excellent local cuisine have all proven to be a big draw for tourists who also want to drive some balls.

But the Algarve's perfect weather means the region needs also to conserve its water. Faro, the regional capital, receives about 500mm of rainfall per year. Most of this rain is concentrated in winter months, meaning that in summer, the courses must irrigate in order keep the greens and fairways from becoming parched.

Nearly all of this sprinkler water is being taken from boreholes.

Prof Pedras and colleagues looked back through three decades of meteorological data and the long time-series of images taken by the US Landsat spacecraft to complete their study. Landsat allows researchers to assess the state of vegetation.

The team could see that although the consumption of water had increased five-fold since 1980, the practices of golf courses had become less wasteful.

The latest grass technology is being used that requires less water; the soils are being managed in a way so that they hold more water; and the irrigation is being done at night. All of these practices work towards more efficient use of water.

It is clear, too, says Prof Pedras, that the greenkeepers and the players recognise that overly lush greens and fairways would be inappropriate.

'I think players who understand the issues and the need to conserve water will accept playing on courses that are a little yellow,' she said. and follow me on Twitter: @BBCAmos

Top award for toxic dump campaigner

An anti-toxic dump campaigner in South Africa has been recognised with a prestigious environmental award.

Desmond D'Sa's efforts resulted in the closure of a chemicals dump in a residential area of Durban, winning him a Goldman Environmental Prize.

The awards are described as 'the Nobel Prize for grassroots environmentalism'.

Mr D'Sa and five other winners will receive their awards on Monday at a presentation ceremony in San Francisco.

As a co-founder of the South Durban Community Environmental Alliance (SDCEA), he campaigned to raise awareness of the plight of communities living alongside the waste facility.

Among the schemes he oversaw were the 'bucket brigade' and the 'smell chart'. The bucket brigade consisted of local residents collecting samples of air in their communities, which where then sent off to the US where they were analysed.

'When we got the results back, we developed a flow chart of all the different smells and odours so then people could be better educated about the chemical odours and the impact they would have on health,' Mr D'Sa recalled.

With the data, Mr D'Sa and his team lobbied the government, which resulted in several health studies being done.

One of the studies showed that more than half of the 300,000-strong population had chronic asthma, he observed.

He added that the study also quantified cancer risk as 25-in-100,000 people, compared with the norm of 1-in-100,000.

'This was a conservative conclusion because the data was conservative yet it showed that the risk was very high and more needed to be done,' Mr D'Sa told BBC News.

Paying the price

In 2009, the facility's operators applied to expand the site licence until 2021, but Mr D'Sa led a campaign to lobby officials, stating that the human cost was too high.

In 2011, the operators withdrew their application and the dump was closed.

'As a result, the trucks that carried all of the highly toxic waste through the communities are no longer there,' he said proudly.

Other winners of the Goldman Prize, which honours and recognises grass-root activists, this year include:

Ramesh Agrawal, India - Using a small internet cafe, Ramesh Agrawal organised villagers to demand their right to information about industrial development projects and succeeded in shutting down one of the largest proposed coal mines in Chhattisgarh.

Ruth Buendia Mestoquiari, Peru - Overcoming a history of traumatic violence, Ruth Buendía united the Asháninka people in a powerful campaign against large-scale dams that would have once again uprooted indigenous communities still recovering from Peru's civil war.

Suren Gazaryan, Russia - Bat expert and zoologist Suren Gazaryan led campaigns highlighting illegal use of federally protected forestland along Russia's Black Sea coast near the site of the 2014 Winter Olympics.

Rudi Putra, Indonesia - Biologist Rudi Putra is dismantling illegal palm oil plantations that are causing massive deforestation in northern Sumatra, protecting the habitat of the critically endangered Sumatran rhino.

Helen Holden Slottje, USA - Using a clause in the state constitution that gives municipalities the right to make local land use decisions, Helen Slottje helped towns across across New York state pass local bans on fracking.

Saturday, April 26, 2014

Uni funding for low carbon projects

Three Scottish universities are to receive £20m as part of a scheme to help Scotland meet its carbon emission reduction targets.

Strathclyde, Stirling and St Andrews universities will be given the Scottish government funding to build a number of new projects.

It is hoped the work will encourage other bodies to develop low carbon heating technologies.

The money has been allocated through the Scottish Funding Council (SFC).

St Andrews University will receive £10m for a wood-fuelled biomass project at Guardbridge in Fife.

'Start Quote

Learning from these kind of projects will help to build investor and consumer confidence in low carbon heating'

End Quote Gina Hanrahan WWF Scotland

The plant will produce hot water to be pumped four miles underground to heat and cool laboratories and residences in the university.

Strathclyde University will receive £8m to construct a combined heat, power and district energy network, linking Strathclyde's campus with major energy users in the area.

A further £2m will be given to Stirling University for the installation of a combined heat and power plant to serve its main campus.

Education Secretary Michael Russell said: 'Today's announcement further underlines both the value of our universities in leading research and innovation, and Scotland's ambitions for low carbon energy.

'Investment for these three universities will not only contribute to reducing our carbon emissions, their work will offer other bodies the opportunity to learn from their work, develop their own projects and further enhance Scotland's global reputation in this area.'

'Important step'

SFC chief executive Laurence Howells said: 'These are exciting investments with huge potential, not least because they tap into the world-leading knowledge within our universities and allow them to show what the future could be for carbon reduction in Scotland.

'We see this as an important step forward but recognise there is still much more to be done. No-one can be complacent about protecting our environment.'

The investment was welcomed by environmental groups.

Gina Hanrahan, of WWF Scotland, said: 'The public sector has a pivotal role in helping to turn low carbon ambition into action.

'Heating Scotland's buildings and water makes up almost half our total carbon emissions, yet only around 3% of that heating is currently renewable.

'For too long heat has been the forgotten part of our energy mix, but it's an area we need to see strong action on from the Scottish government if we're to tackle climate change and insulate our buildings from rising energy costs and volatile fossil fuel markets.

'Learning from these kind of projects will help to build investor and consumer confidence in low carbon heating.'

How sloths breathe upside down

A Swansea University team has found out how sloths are able to spend up to 90% of their lives hanging upside down yet continue breathing normally.

The research found the mammals, which live in the rainforests of south and central America, have a way of fixing their internal organs to the rib cage.

These adhesions prevent the stomach, liver, kidneys and even the bowels and bladder from pressing on the diaphragm.

The research carried out in Costa Rica is published by the Royal Society.

The scientists say much is still to be learned about these illusive and endangered creatures - the world's slowest mammals - as even basic information such as their natural diet and habitat preference remains a mystery.

PhD zoology researcher Rebecca Cliffe, 24, is one of the authors of the paper, based on work at the Sloth Sanctuary of Costa Rica.

She said: 'With an extremely slow metabolic rate and low energy diet, sloths are experts at saving energy.

'They have a very slow rate of digestion and can store up to a third of their body weight in urine and faeces. For a mammal that spends a significant amount of time hanging upside down, this large abdominal weight pressing down on the lungs would make breathing very costly in terms of energy, if not impossible.

'Sloths have solved this problem by anchoring their organs against the rib cage.

Sloth facts

  • The sloth is the world's slowest mammal, so sedentary that green algae grows on its coat, which helps camouflage it

  • They sleep for 15-20 hours a day and even when awake will remain motionless

  • Sloths carry up to a third of their bodyweight in urine and faeces and will only defecate once a week

  • Sloths are endangered.

SOURCE: Swansea University

'They have multiple internal adhesions that bear the weight of the stomach and bowels when the sloth hangs inverted. We estimate that these adhesions could reduce a sloths energy expenditure by 7% - 13% when hanging upside down.

To a sloth, an energy saving of 7% - 13% is a big deal. They generate just about enough energy from their diet to move when and where required, but there is not much left in the tank afterwards.

'It would be energetically very expensive, if not completely impossible, for a sloth to lift this extra weight with each breath were it not for the adhesions. The presence of these simple adhesions therefore really is vital.'

Prof Rory Wilson, of the College of Science at Swansea University, a joint author of the paper, said: 'Nothing that sloths do is normal.

'They are quite the most extraordinary and 'off-the-wall' mammals I have ever come across and yet we know so very little about them.

'How foolish we would be to watch these creatures become victims of deforestation and habitat fragmentation and the like without having the slightest idea how to help.'

Friday, April 25, 2014

SpaceX rocket stage in soft return

SpaceX says its recent experiment to return part of its Falcon-9 rocket back to Earth under control was a success.

The US company has confirmed that the first-stage of the vehicle launched from Cape Canaveral a week ago used its engines to slow its fall, deployed a set of legs and made a 'soft landing'.

For safety reasons, the touchdown was actually commanded to take place east of the Cape, far out at sea.

Nonetheless, the stage was vertical and had zero velocity on contact.

The company has video of the event - albeit of poor quality - that it plans to post on its website.

Extremely rough seas meant that a boat could not get to the scene for two days to try to salvage the stage before it sank.

Potentially, the experiment has enormous significance for the space industry.

Traditionally, rockets have been expendable.

As a vehicle makes an ascent, it dumps propellant stages, which then fall to destruction, torn apart as they tumble end over end.

SpaceX believes if it can recover those stages and fly them again and again, the cost of access to space could be dramatically reduced.

'No-one has ever soft-landed a liquid-rocket boost-stage before,' said SpaceX chief designer Elon Musk. 'I think this bodes well for achieving reusability.

'What SpaceX has done thus far is evolutionary, not revolutionary. [But] if we can recover the stage intact and re-launch it, the potential is there for a truly revolutionary impact in space transport costs.'

The first-stage of a Falcon-9 - the segment that gets the vehicle up off the pad - represents about 70% of a flight's $60m price tag.

Mr Musk told reporters that reusable stages could therefore lead to a tenfold reduction in that ticket price.

The company will now further refine its technology with the aim of making a return to dry land by the end of the year.

It needs to reduce the error on touchdown to a maximum of a mile. However, Mr Musk believes there is no reason why a return could not have the same accuracy as a helicopter, which comes to rest within feet of its intended landing location.

Discussions are already under way with the US Air Force, which runs the Cape Canaveral launch complex, to identify a suitable landing zone on the Florida coast.

The Friday 28 April experiment, which followed the successful launch of the Dragon cargo ship to the space station, was actually the second time SpaceX had tried a controlled return.

The first attempt in September last year saw the stage lose control late on, as propellant for the engines gradually spun up inside their tanks.

Thrusters to correct the attitude of the stage were beefed up for this second experiment.

SpaceX also attached the landing legs for the first time. The telemetry confirmed these extended properly just prior to the stage touching water.

Reusability does not come without a penalty. The fuel needed for the manoeuvres and the weight of the landing gear impacts the rocket's ultimate performance - the maximum payload it can carry to orbit. Mr Musk has previously calculated this penalty to be about 30%.

He also recognises that some of his customers may be uncomfortable flying their satellites on what amount to second-hand rockets.

'I think what we'll have to do is do a demonstration re-flight without an operational satellite onboard. And if that demonstration re-flight works, and some customers may want more than one - then that's the thing that would really ultimately convince them,' he said.

Mr Musk was speaking to reporters at the National Press Club in Washington DC. He used the press conference to announce also that the company had filed a suit to protest against the way rockets were being procured for national security missions, which include military spacecraft and spy satellites.

Thirty-six vehicles were recently ordered en bloc by the United States Air Force from United Launch Alliance, a joint venture between Boeing and Lockheed Martin.

Mr Musk said the absence of a competition 'doesn't seem right', and claimed the use of ULA's Atlas rockets was a poor deal for US taxpayers.

'The ULA rockets are basically four times more expensive than ours. So this contract is costing the US taxpayer billions of dollars for no reason. And to add salt to the wound, the primary engine used is made in Russia.'

Agreement reached on deep sea mining

Plans to open the world's first mine in the deep ocean have moved significantly closer to becoming reality.

A Canadian mining company has finalised an agreement with Papua New Guinea to start digging up an area of seabed.

The controversial project aims to extract ores of copper, gold and other valuable metals from a depth of 1,500m.

However, environmental campaigners say mining the ocean floor will prove devastating, causing lasting damage to marine life.

The company, Nautilus Minerals, has been eyeing the seabed minerals off Papua New Guinea (PNG) since the 1990s but then became locked in a lengthy dispute with the PNG government over the terms of the operation.

Under the agreement just reached, PNG will take a 15% stake in the mine by contributing $120m towards the costs of the operation.

Mike Johnston, chief executive of Nautilus Minerals, told BBC News: 'It's a taken a long time but everybody is very happy.'

'There's always been a lot of support for this project and it's very appealing that it will generate a significant amount of revenue in a region that wouldn't ordinarily expect that to happen.'

The mine will target an area of hydrothermal vents where superheated, highly acidic water emerges from the seabed, where it encounters far colder and more alkaline seawater, forcing it to deposit high concentrations of minerals.

The result is that the seabed is formed of ores that are far richer in gold and copper than ores found on land.

Mr Johnston said that a temperature probe left in place for 18 months was found to have 'high grade copper all over it'.

For decades, the idea of mining these deposits - and mineral-rich nodules on the seabed - was dismissed as unfeasible because of the engineering challenge and high cost.

But the boom in offshore oil and gas operations in recent years has seen the development of a host of advanced deep sea technologies at a time when intense demand for valuable metals has pushed up global prices.

The mine, known as Solwara-1, will be excavated by a fleet of robotic machines steered from a ship at the surface.

The construction of the largest machine, a Bulk Cutter weighing 310 tonnes, has just been completed by an underwater specialist manufacturer, Soil Machine Dynamics (SMD), based in Newcastle, UK.

The plan is to break up the top layer of the seabed so that the ore can be pumped up as a slurry.

The agreement with PNG now clears the way for Nautilus to order a specialist vessel to manage the operation. Mining itself could start within five years.

Environmental campaigners have long argued that seabed mining will be hugely destructive and that the precise effects remain unknown.

Richard Page, oceans campaigner for Greenpeace, said: 'The emerging threat of seabed mining is an urgent wake-up call for the need to protect the oceans.

'The deep ocean is not yet mapped or explored and so the potential loss of fauna and biospheres from mining is not yet understood.

'Only 3% of the oceans and only 1% of international waters are protected, which makes them some of the most vulnerable places on earth - what we desperately need is a global network of ocean sanctuaries.'

According to Nautilus, the mine will have a minimal environmental footprint, covering the equivalent of about 10 football fields and focusing on an area which is likely to be rapidly re-colonised by marine life.

Mr Johnston said: 'It's a resilient system and studies show that life will recover in 5-10 years. An active venting site 1km to the southeast has the same bugs and snails and the current will carry the bugs and snails to the mine site. We expect it to recover quite quickly.'

But this will be the first attempt to extract ore from the ocean floor, so the operation - and the company's assurances about the impacts - will be watched closely.

So far, 19 licences to search for seabed minerals have been awarded by the International Seabed Authority, the UN body policing this emerging industry.

The International Seabed Authority (ISA), which has welcomed the Nautilus Minerals agreement with Papua New Guinea, is currently drawing up guidelines for the environmental management of future seabed mining.

Michael Lodge of the ISA told the BBC: 'This is a very exciting opportunity and we are looking forward to learning from the tests of the new machine, which is a world first and should give us some valuable insights into technical feasibility and environmental impact.'

Thursday, April 24, 2014

UK science to get £200m polar ship

UK science is to get one of the biggest, most capable polar research vessels in the world.

The £200m investment in an icebreaker is to be announced by Chancellor George Osborne in a speech on Friday.

The ship is likely to be 130m long, and sport a helipad, cranes, onboard labs, and have the ability to deploy subs and other ocean-survey and sampling gear.

It should be ready to enter service in 2019, and will support scientists in both the Antarctic and the Arctic.

The strength of its hull will allow it to push deeper into pack ice than any previous British research vessel.

'Start Quote

The new ship will be a clear statement of the UK's commitment to science in the Antarctic and South Atlantic, and increases our ice-breaking capability in the South and, just as important, in the Arctic'

End Quote Prof Duncan Wingham Nerc chief executive

Initial technical specifications require the ship to be able to maintain a speed of three knots while breaking through 2m-thick floes.

The money to build and equip the vessel is coming from the government's capital investment fund for science, for which Mr Osborne has committed £1.1bn per year in real terms up to 2020/21.

Talking ahead of his announcement in Cambridge, the chancellor said science was a springboard for economic prosperity.

'Backing British science, supporting businesses seeking to grow off the back of it and protecting investment in it is a central part of our long-term economic plan,' he explained.

'Britain has a proud past leading the world in pushing the boundary of scientific discovery. I want it to be a mark of our future success.'

The UK already operates two polar ships - the Royal Research Ship (RRS) James Clark Ross and the RRS Ernest Shackleton.

The former was built in 1990 and the latter in 1995.

A case was made to government, and accepted, that this fleet needed to be augmented with a more modern capability if the nation's science at high latitudes was to remain competitive.

An early design concept for the new ship has been drawn up by naval architects, but this will need to be finessed.

A clear imperative is that the final design features a helideck - something omitted on the Clark Ross and which experts have told the BBC is really essential for effective Antarctic operations.

Precisely where the ship will be built is an open question.

Given the scale of the investment, a home shipyard would obviously be preferred. But European Union rules will require that bids be invited also from beyond the UK.

There is sure to be some concern that the announcement of the new vessel will signal an imminent reduction in the fleet - one super ship to replace two ageing vessels.

Global warming does not mean an end to polar ice nor to the need for icebreakers. Even if the Arctic becomes largely ice-free in summertime later this century, as the latest science suggests, the legacy of each winter's deep freeze will still litter the ocean - some of the jagged shards of ice will be visible but many will bob treacherously just below the surface.

While reporting on an expedition through Canada's fabled Northwest Passage in October 2007, I woke to the sound of an unnerving clanging along the hull. The vessel, the Amundsen, was pushing through pack ice and each jolt and reverberation made me wonder about the strength of the steel. But to understand how the polar regions are changing, and the implications for everything from wildlife to fishing to new oil fields to future shipping routes, the view from space offered by satellites is not enough.

For decades to come, the most detailed research will require tough vessels to venture into the midst of what has become a messy and hazardous scene.

But the Natural Environment Research Council (Nerc), which funds polar science in the UK, says this is not the current plan.

The desire is to operate both the Clark Ross and the Shackleton until at least the end of the decade, it states.

A decision will then be taken on what to do with the Shackleton, which, unlike the Clark Ross, is not British-owned but leased from a Norwegian company.

The first of five available one-year extensions to this bareboat charter arrangement comes into effect in August.

Nerc has made it clear also that the capital investment for the new ship will not impact the budget for its day-to-day science or ongoing infrastructure needs. The investment is on a separate government line.

The council has recently upgraded its 'bluewater fleet' - the open-ocean vessels RRS Discovery and RRS James Cook are both less than 10 years old.

Prof Duncan Wingham, the chief executive of Nerc, told BBC News: 'The new vessel will make Nerc's entire fleet, ton for ton, the most advanced scientific fleet in the world.

'The new ship will be a clear statement of the UK's commitment to science in the Antarctic and South Atlantic, and increases our ice-breaking capability in the South and, just as important, in the Arctic.'

What the new polar ship promises to be like

  • Likely to have a length of 130m and a breadth of 25m

  • Its gross tonnage would be about 13,000 tonnes

  • Its cargo volume would be around 4,200 cu metres

  • It must be self-sufficient to operate for up to 80 days

  • This means it could cover roughly 24,000 nautical miles

  • Helicopter facilities are today considered a must-have

  • It would launch aerial and ocean robotic systems

  • Up to 60 scientists and support staff could live aboard

UK's existing polar research vessel capability

  • James Clark Ross (above) was built on Tyneside and is UK-owned

  • Ernest Shackleton's bareboat charter has just been extended

  • Both are flagged in the Falklands but operate in the North too

  • They resupply Antarctic bases, including remote Halley Station and follow me on Twitter: @BBCAmos

Mystery of dazzling supernova solved

An exceptionally bright supernova that baffled scientists has been explained.

It is so luminous because a galaxy sitting in front amplifies its light - making it appear 100 billion times more dazzling than our Sun.

This cosmic magnifying glass lay hidden between Earth and the supernova - and has now been detected with a telescope in Hawaii.

'Start Quote

Our explanation required a bit of magic... and scientists don't generally buy into magic'

End Quote Dr Robert Quimby University of Tokyo

The discovery, reported in the journal Science, settles an important controversy in the field of astronomy.

In 2010, a team of scientists observed the supernova, PS1-10afx, shining 30 times brighter than any other in its class.

They concluded it was a completely new type of stellar explosion.

But while there are a few, rare supernovas that have been found with comparable luminosities, there was something odd about this one, according to Dr Robert Quimby of the University of Tokyo's Kavli Institute.

'PS1-10afx was different in just about every way. It evolved too fast, its host galaxy is too big, and it was way, way too red,' he explained.

His team had another idea. They ventured that PS1-10afx was a normal Type Ia supernova magnified by a lens in the form of a massive object, such as supermassive black hole, nearby.

The only problem: 'We had no direct evidence for the lens,' said Dr Quimby.

'Thus [our] explanation required a bit of magic... and scientists don't generally buy into magic.'

However, he reasoned that if there was a gravitational lens magnifying the supernova, this lens would still be there today - even though the supernova has faded away.

To find it, his team used the Keck telescope in Hawaii to observe PS1-10afx's host galaxy.

'Looking at the spectra we could check to see if there was light coming from two sources at two separate distances, which is what we found,' said Dr Quimby.

'There is a second, previously unidentified galaxy, hiding in plain sight in front of the supernova.'

The lens galaxy was missed previously because its light was lost in the bright glare of the supernova, the authors say.

'Although the lens galaxy is closer to us, it appears fainter because it has older stars that, like flashlights with old batteries, don't shine as bright,' said Dr Quimby.

The Universe was almost a billion years younger when the supernova exploded than when its light rays were bent by the foreground lens.

'Although this warping of space time probably created four separate images of the supernova when viewed from Earth, we find that these likely appeared as a single source after atmospheric blurring,' said Dr Quimby.

The discovery could provide astronomers with a new tool to measure the expansion of the Universe.

That's because PS1-10afx is the first supernova of its kind to be magnified by 'strong gravitational lensing' - where multiple images of the supernova are formed - creating the extra-bright appearance.

'Each image will arrive at a different time with the exact delay dependent on how fast the Universe is expanding. In principle, measuring this delay provides a direct way to measure cosmic expansion,' Dr Quimby explained.

Unfortunately, the scientists could not do this with PS1-10afx because it faded away before its importance was recognised. But now they know what to look for.

'Our discovery implies there are many more gravitationally lensed supernovae that are barely resolved, like PS1­10afx,' said Prof Masamune Oguri, of the University of Tokyo.

'Our selection method can soon be applied to future surveys to improve our understanding of the expanding Universe.'

Blood 'is not from headless king'

A sample of blood long thought to belong to French King Louis XVI is probably not authentic, scientists say.

An elaborately decorated gourd was thought to contain a handkerchief that had been dipped in the king's blood after he was killed by guillotine by French revolutionaries in 1793.

But scientists have now sequenced the genome of the sample and say it is unlikely to belong to the monarch.

The study is published in the journal Scientific Reports.

Instead, the team thinks the gourd and its contents were probably the work of an 18th Century fraudster hoping to make some money from a revolutionary souvenir.

Prof Carles Lalueza-Fox, from the Institute of Evolutionary Biology in Barcelona, Spain, said: 'In the French revolution, the guillotine was working every day - and probably it was much more easy to approach the scaffold when non-important people were being beheaded.

'Maybe that was one of the occasions. They thought nobody was going to be able recognise whether the blood was from the king or not.'

The blood-stained cloth was stored in a hollowed-out gourd, which for the last century was in the hands of an Italian family.

'Start Quote

It really looks like we don't have the king here'

End Quote Carles Lalueza-Fox Institute of Evolutionary Biology

The squash is decorated with images of revolutionary heroes and inscribed with text that says: 'On January 21, Maximilien Bourdaloue dipped his handkerchief in the blood of Louis XVI after his decapitation.'

Early forensic tests suggested it was possible that this was the blood of the French king. But this latest research casts doubt on its royal provenance.

To investigate, the scientists examined stretches of the sample's genome that relate to physical appearance.

Portraits of Louis XVI depict him with blue eyes, but this sample belongs to a person who was far more likely to have had brown eyes.

'The probability of this guy having blue eyes is very low - it is about 3%,' said Prof Lalueza-Fox.

Historical records, including correspondence from Louis XVI's wife, Marie-Antoinette, also state that the king was very tall.

While the average height was about 167cm (5ft 5in) at this time, the King was thought to be at least 185cm (6ft 1in) in height.

Prof Lalueza-Fox said: 'Not all the genetic basis of height is known. However, we do know the genetic markers in extreme cases for very tall people or very small people.

'But this sample doesn't have an excess of markers that could be related to a very tall person. It really looks like we don't have the king here.'

The scientists also looked at genetic ancestry, which shows which parts of Europe a person's ancestors came from.

The DNA from the sample suggests the individual had roots that traced mainly back to France and Italy, while many of Louis XVI's ancestors came from Germany and Poland.

The team concludes that it's extremely unlikely that this is Louis XVI's blood.

This supports another study published last year that compared the sample to two living relatives of Louis XVI, and cast doubt on its authenticity.

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UK team to shoot for fusion record

The director of a UK science facility says it will try to set a new world record in nuclear fusion.

The Jet experiment in Oxfordshire was opened in 1984 to understand fusion - the process that powers the Sun.

Prof Steve Crowley told the BBC a go-ahead to run Jet at maximum power would allow scientists to try for the record by the end of the decade.

This could bring Jet up to the coveted goal of 'breakeven' where fusion yields as much energy as it consumes.

Fusion is markedly different from current nuclear power, which operates through splitting atoms - fission - rather than squashing them together as occurs in fusion.

'We're hoping to repeat our world record shots and extend them,' Prof Crowley told BBC News.

'Our world record was from 1997, we think we can improve on it quite considerably and get some really spectacular results. We're winding up to that and by the end of the decade we'll be doing it.'

Joint European Torus (Jet)

  • Initiated as part of European programme to explore nuclear fusion

  • Opened in Culham, Oxfordshire, in April 1984 by the Queen

  • Achieved world record energy gain factor in 1997

  • Served as prototype for multi-bn-euro Iter project due to come online in the 2020s

  • Will conduct dress rehearsals for Iter over next five years of operation

Despite its history spanning some five decades, scientists hoping to harness fusion have faced many hurdles. But it remains an attractive prospect because it can yield a near limitless supply of clean energy.

The fusion community hopes their luck could change when the multi-bn-euro Iter fusion experiment comes online in Cadarache, in the south of France, in the 2020s. And officials from Jet, based at Culham, Oxfordshire, are now in the process of signing a contract that will keep the facility running for another five years.

Jet (Joint European Torus) was the prototype for Iter and over its extended lifetime will effectively carry out a dress rehearsal for that much bigger reactor, which will aim to demonstrate the scientific viability of fusion power at scale.

During Jet's extended run, scientists will again begin using the deuterium-tritium fuel mix needed for maximum fusion power. Until recently, scientists had been running the experiment using deuterium fuel only. While running the experiment in this mode allows scientists to gather valuable scientific knowledge, both deuterium and tritium will be needed to exceed the record set by the Oxfordshire facility 17 years ago.

'Jet is the only machine in the world that can handle that fuel. When you put tritium in, it reacts like crazy,' said Prof Crowley.

Jet uses the same approach to fusion as Iter. This is known as magnetic confinement fusion (MCF), in which electrically charged gas called plasma is heated to millions of degrees inside a sealed tube called a 'tokamak'.

Fusion facts

  • Fusion is the process that powers the stars, including the Sun

  • One litre (1.75 pints) of water contains enough deuterium, when fused with tritium, to produce the equivalent energy of 500 litres of petrol

  • A 1,500MW fusion power station would consume about 600g (1lb 5oz) of tritium and 400g of deuterium a day

  • The first large-scale use of fusion was by the US military with the detonation of Ivy Mike, a hydrogen bomb, on 1 November 1952

  • Iter and Jet's designs involve a tokamak, the Russian word for a ring-shaped magnetic chamber

  • Iter's magnetic field is designed to contain 100-million-C plasma, the temperature required for the fusion process

  • The US, while supporting Iter as a partner, is also funding the National Ignition Facility, which uses lasers to heat and compress hydrogen to the point of fusion

  • South Korea, another Iter partner, is investing $941m in a fusion technology demonstrator, K-DEMO, which could be the first to generate grid power

  • Critics object to further research into nuclear power and question the likely costs of commercial operations

The temperature inside Jet during one of its full power shots can soar to a scorching 200 million C. That's more than 10 times the temperature at the centre of the Sun - estimated to be about 15 million C.

In 1997, scientists pushed 24MW of energy into Jet and managed to get 16MW out - a fusion energy gain of about 0.7. A fusion energy gain factor (known as Q) of greater than one is required to achieve 'breakeven', where the amount of energy produced equals the amount of energy consumed.

However, higher gain factors are required to achieve self-sustaining fusion, where the reactions continue without any external input of energy.

'We hope in the next runs of Jet that we'll approach a gain of one. But that's no good for energy production - you need a gain of 10, 20, 30 - much more energy coming than you put in. That's what Iter will do,' said Prof Crowley.

Jet was the result of a European plan for fusion power conceived in the 1970s. Recently, the machine has undergone a series of upgrades to bring components in line with those planned for Iter. In coming years, it will shed light on some of the challenges for making fusion a success.

'The plasma is spewing out tank shells of neutron particles. The neutrons that come out of fusion are 10 times more energetic than those coming out of nuclear fission,' said Prof Crowley.

'When they slam into the walls [of the tokamak] they rearrange the atoms in those walls. The question is can we have a material that doesn't mind having its atoms rearranged 10 times a year?'

In magnetic confinement experiments the plasma can become unstable, causing fusion to break down. However, improving performance is partly a matter of scale - and as Iter is likely to demonstrate - bigger really is better, as far as fusion is concerned.

In November 2013, the European Parliament formally endorsed the European Commission's 80bn-euro Horizon 20-20 research budget. This encompasses funds of about 300m euros to keep Jet running. Officials are currently finalising details of the settlement, with a view to signing the contract soon.

The National Ignition Facility in the US recently passed a fusion milestone of its own. NIF takes a different approach to fusion from that taken by Jet and Iter, concentrating laser energy on a hydrogen fuel pellet to initiate fusion.

During a run of the experiment in September 2013, the small amount of energy released through the fusion reaction exceeded the amount of energy being absorbed by the fuel - a first at any fusion facility.

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Tuesday, April 22, 2014

Mystery of 'ocean quacks' solved

The mystery of a bizarre quacking sound heard in the ocean has finally been solved, scientists report.

The noise - nicknamed 'the bio-duck' - appears in the winter and spring in the Southern Ocean. However, its source has baffled researchers for decades.

Now acoustic recorders have revealed that the sound is in fact the underwater chatter of the Antarctic minke whale.

The findings are published in the Royal Society journal Biology Letters.

Lead researcher Denise Risch, from the US National Oceanic and Atmospheric Administration (Noaa) Northeast Fisheries Science Center in Massachusetts, said: 'It was hard to find the source of the signal.

'Over the years there have been several suggestions... but no-one was able to really show this species was producing the sound until now.'

If it quacks like a duck

The strange sound was first detected by submarines about 50 years ago. Those who heard it were surprised by its quack-like qualities.

'Start Quote

It was either the animal carrying the tag or a close-by animal of the same species producing the sound'

Since then, the repetitive, low frequency noise has been recorded many times in the waters around the Antarctic and western Australia. Suggestions for its source have ranged from fish to ships.

The researchers now say they have 'conclusive evidence' that the bio-duck is produced by the Antarctic minke whale.

In 2013, acoustic recorders were attached to two of the marine mammals and recorded the whales making the strange noise.

Dr Risch said: 'It was either the animal carrying the tag or a close-by animal of the same species producing the sound.'

The researchers do not yet know under what circumstances the minke whales make their distinctive vocalisations, although the sounds that were recorded were produced close to the surface and before the mammals made deep dives to feed.

The team says solving this long-standing mystery will help them to learn more about these little-studied animals.

Dr Risch said: 'Identifying their sounds will allow us to use passive acoustic monitoring to study this species.

'That can give us the timing of their migration - the exact timing of when the animals appear in Antarctic waters and when they leave again - so we can learn about migratory patterns, about their relative abundance in different areas and their movement patterns between the areas.'

The team will be analysing data from the PALAOA station, the Alfred Wegener Institute's (AWI) permanent acoustic recording station in Antarctica, which has been recording in the Southern Ocean continuously in the last few years.

This is not the only acoustic puzzle that scientists have recently shed light on

Another baffling low frequency noise - called The Bloop - turned out to be the sound of Antarctica's ice cracking.

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Asteroid impact risks 'underplayed'

A visualisation showing where sizeable asteroids have hit the Earth in recent years has been released by the B612 Foundation.

The US-based group, which includes a number of former Nasa astronauts, campaigns on the issue of space protection.

It hopes the visualisation will press home the idea that impacts are more common than we think.

The presentation leans on data collected by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO).

The CTBTO operates a network of sensors that listens out for clandestine atom bomb detonations.

Between 2000 and 2013, this infrasound system catalogued 26 major explosions on Earth.

None were caused by A-bombs; they were all the result of asteroid strikes.

They ranged in energy from one to 600 kilotons. By way of comparison, the bomb that destroyed the Japanese city of Hiroshima was a 15-kiloton device.

Fortunately, most of these space rocks disintegrated high up in the atmosphere and caused few problems on the ground.

A few, people will have heard about, such at the 20m-wide object that ripped across the sky above the Russian city of Chelyabinsk last year.

But many will have gone unseen because they occurred far out over the oceans.

And the B612 Foundation makes the point that none of the 26 events were tracked in advance. There were no warnings.

The advocacy group uses the frequency and size range of the impacts to say something about the probability of larger strikes in the future.

Because although Chelyabinsk was a terrifying experience for those caught up in it, the event itself was quite small compared to some of the incomers recorded through Earth history.

The foundation says the CTBTO data would suggest that Earth is hit by a multi-megaton asteroid - large enough to destroy a major city if it occurred over such an area - about every 100 years.

Remembering the Tunguska event of 1908 - it was fortunate that that object, thought to be about 45m wide, struck a very remote part of the globe.

'This is a bit like earthquakes,' explains Ed Lu, former shuttle astronaut and CEO of the B612 Foundation.

'In the cities that have a major danger - Tokyo, Los Angeles, San Francisco - they know the odds of big earthquakes by observing how many small earthquakes there are. Because there's a known distribution of earthquakes, meaning that earthquakes come in all sizes, small to large - if I can measure the small ones, I know how many big ones they're going to be. And you can do this with asteroids.

'These asteroid impacts in the last decade have been ones that we haven't had much data on until recently, and they tell us that in fact asteroid impacts are more common than we thought,' he told BBC News.

B612 is pushing its Sentinel telescope concept as way to better quantify and mitigate the risks.

Projected to be ready for launch in 2018 and costing some $250m, the venture is being funded privately through donation.

The observatory would be sited in a Venus-like orbit, looking out towards Earth.

This would help pick up those inner-Solar-System rocks that go unseen by current telescopes at Earth because they are hidden in the glare of the Sun.

Sentinel would also operate in the infrared - the best part of the spectrum to go and look for dark grey asteroids.

Previous surveys have suggested that we have probably found a little over 90% of the true monsters out there - the objects that could lead to extinction if they struck the Earth. And the good news is that none look like they will hit us anytime soon.

But data from Nasa's Wise telescope suggests that the population of objects in the 100-1,000m size range may number close to 20,000, and the vast majority of these have yet to be identified and tracked.

Time is precious in this business. The sooner an Earth-bound rock is detected, the easier it is to deal with it.

Mitigation might be as simple as hitting the asteroid with a heavy block. This nudge would change the velocity of the rock ever so slightly, but if it is done way ahead of time, it should be just enough to make the object arrive 'at the crossroads' sufficiently early or late to miss Earth.

Another 'simple' approach being talked about is the so-called 'gravity tractor'. This involves positioning a spacecraft close to a target object and using long-lived ion thrusters to maintain the separation between the two. Because of the gravitational attraction between the spacecraft and the asteroid, it is possible to pull the rock off its trajectory. Relatively straightforward but, again, it requires time to work.

'These types of mission are arguably less difficult than building Sentinel. The hard part is finding these things,' says Lu.

'Picture trying to spot something that's only the size of a small apartment building, that's tens of millions of miles from Earth, and that's black against a black background. That's incredibly hard. That's what requires the technological advances of Sentinel.'

  • Sentinel would track 90% of Earth-orbit-crossing asteroids larger than 100m, and 50% of the 30m rocks

  • Its observation orbit would be close to that of Venus; it would lap the Earth every 2.2 years

  • B612 says it would give years/decades of notice before any potential impacts with Planet Earth