Scientists have found compelling evidence that a water channel flowed through the West Antarctic ice sheet just 125,000 years ago. The discovery of the prehistoric seaway sheds new light on the stability of the third largest ice mass on the planet which will have a huge impact on global sea levels if it melts.

The research, published in the journal Global Change Biology is the most comprehensive study of its kind. Scientists from the British Antarctic Survey (BAS) pieced together all available data on bryozoan abundance and diversity across Antarctica from the mid nineteenth century to the present. The researchers, part of the Census of Antarctic Marine Life (CAML), initially set out to investigate the origins of the diverse marine fauna living in Western Antarctica. But when comparing two isolated seas they found something puzzling. “When we sampled the Weddell and Ross seas we found incredibly similar fauna,” says David Barnes, marine ecologist at the British Antarctic Survey who led the research team. The two seas are only 1,500 miles apart. But they are separated by the West Antarctic ice sheet, a vast impenetrable block of ice two kilometres deep in its thickest point.

So how could such related fauna develop in these isolated conditions?

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Scientists have successfully implanted a biosynthetic alternative to the human cornea in the first clinical study of it’s kind. The research, published in Science Translational Medicine today, is a 24 month follow-up of the phase one clinical study led by Per Fagerholm, Professor of Ophthalmology at Linköping University. The cornea is a vital component of the eye acting as the outermost lens, controlling and focusing light as it enters the eye as well as shielding it from germs and infection. However, millions of people worldwide suffer from corneal disease and damage, which can lead to blindness. Currently, the best way to correct corneal damage is through transplanting a human donor cornea. But there is a huge worldwide shortage of human donor corneas, and eye and tissue banking is not carried out in many countries because of concerns with donor-derived infection.

The new findings by Fagerholm and his colleagues could make the long waiting lists for replacement corneas a thing of the past. “Produced from human collagen the artificial biological cornea mimics the corneal structure and is aimed at promoting regeneration.” explains Fagerholm, also a corneal surgeon who carried out the implant operations. However, ten years ago when studies into the biosynthetic collagen cornea were starting to progress, most researchers were sceptical. “A decade ago most researchers were concentrating on synthetic [plastic] cornea research,” says May Griffith, Professor of Regenerative Medicine at Linköping University, Sweden and co-author of the study. "But in 1999 we showed it was possible could reconstruct the cornea. " she says referring to her research published in Science which was the basis for getting the biosynthetic approach into clinical trials.

In 2007, after five years of pre-clinical testing and regulatory hurdles, ten patients were chosen for the phase one clinical study. “The study was designed to test the safety of the novel biosynthetic corneas.” says Griffiths. Patients were chosen with corneal damage and disease focusing on those suffering from advanced keratoconus or a central scar.

Two years and nine months into the study the results are encouraging. “After two years six out of the ten patients saw their vision improve and the eyesight of all ten improved with contact lenses with one patient restoring 20-20 vision,” she says. And as the researchers monitored the patients recovery, other results were surprising. “Normally when human donor corneas are implanted, drugs including steroid immunosuppressions are given for between six months and one year as a preventative measure to ward off infection.” says Griffith. “However using biosynthesized corneas we phased the steroids out after about seven weeks because the patients showed no signs of needing them after the post-operation inflammation had gone down,” says Griffith.

Not only this, but the human nerve regeneration was unprecedented. In nine out of ten patients nerves regenerated and the cornea was sensitive to mechanical stimulation. “In human donor corneas the nerves don’t always grow back.” says Griffith. “So we were very happy to see nerve densities increasing in the two years after implantation of biosynthetic corneas. We had seen nerves growing back in tests with healthy animals, but we were unsure what to expect”.

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The European Space Agency is one step closer today to restoring data transmission from it’s Earth Observation satellite. First launched on 17 March 2009 (see ‘Gravity Mission to launch’) the Gravity and Ocean Circulation Experiment (GOCE) is renowned for it’s high resolution datasets on earth’s gravity gradients. However on 18 July 2010, 17 months into the mission, the satellite lost the ability to transmit science data. The satellite had previously developed computer glitches in February 2010 and data transmission was finally suspended when the back-up computer system developed communication problems.

Following earlier reports on the satellite’s status (see BBC) the outlook today is looking more positive. “We’re in a better situation and making progress” says Mark Drinkwater, head of the mission science division, European Space Research and Technology Centre (ESTEC) headquarters in Noordwijk, The Netherlands.

“Today is an important milestone in solving the telemetry anomaly because we have applied software patches to the satellite’s computer systems which enable monitoring of the onboard health of the satellite by downloading status information" explains Drinkwater who has been involved with the design and development of the GOCE ‘Earth Explorer’ mission since the end of the 1990’s.

And the science has continued despite telemetry glitches. “There is no reason to believe that the gradiometer, GPS and star trackers are not perfectly nominal and working fine – we just can’t get science data to the ground” Drinkwater explains.

As the lowest orbiting environmental spacecraft, the GOCE satellite circles in the earth’s atmosphere just 250 km above the surface. This allows extremely accurate environmental datasets at an unprecedented spatial resolution with a real societal benefit.

“The GOCE datasets are set to revolutionize scientist’s ability to monitor and predict sea level rise, a growing concern in a changing climate” says Drinkwater.

The instrument in question is the first three-dimensional gradiometer. “Previous gravity data measurements could be regarded as monochrome by comparison to the fantastic new technicolour details captured in GOCE gradiometer gravity gradient data. Meanwhile, its uniform global high resolution products at 100 km grid scale, such as the geoid height – a proxy for sea level – is approaching the unprecedented accuracy of 1-2cm” says Drinkwater.

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Researchers have confirmed widespread plastic pollution across areas of the Caribbean and the Northwest Atlantic Ocean. First announced at the Ocean Sciences Meeting in Portland, Oregon, United States in February 2010 (see BBC) the two-decade-long study is published in Science today.

“It is the most extensive description of plastic in the North Atlantic Ocean” says Kara Lavender Law, a physical oceanographer at the Sea Education Association and lead author of the study.

The plastic in question is swirling around a vortex of ocean currents called the North Atlantic Gyre and, according to the researchers, is comparable in size to the better-known ‘Great Pacific Garbage Patch’ (now immortalised in this Dilbert cartoon). The study was led by the Sea Education Association in Woods Hole, Massachusetts which has monitored the Western Atlantic for 22 years (1986 to 2008).

Following annually-repeated cruise tracks, the sea surface has been routinely sampled for plastic and other debris using towed nets. After 6,100 tows, and using computer simulations to model the ocean circulation, the researchers have shown the plastic piles up where wind-driven surface currents converge.

“The plastic is following the physical currents,” explains Law “and it accumulates in the North Atlantic Gyre.”

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Climate change, rather than human hunters, drove the wooly mammoth to extinction. That’s the claim from scientists who say that the hairy beasts lost their grazing grounds as forests rapidly replaced grasslands after the last ice age, roughly 20,000 years ago.

The researchers used palaeoclimate and vegetation models to simulate the plant cover across the mammoths’ habitat around that time. And the results are striking. “The landscape at the last glacial maximum would have been dominated by grasses and small shrubs and bushes, a perfect vegetation for mammoths and other megafaunal grazers,” explains Judy Allen, a palaeoecologist at Durham University, UK and lead author of the study. “But as the climate warmed, the mammoths habitat of grassland was completely taken over by forest,” she says. The tree takeover was boosted by more intense sunlight and higher levels of carbon dioxide in the atmosphere. (see BBC and Daily Telegraph).

Not only did this change happen across a vast area covering modern day Europe and North America, it also happened very fast. “We’re talking about a warming over a 2,000 to 5,000 year period,” says Brian Huntley, a Durham palaeoecologist and co-author of the study. “In just a few thousand years the mammoth’s habitat and food source more or less disappeared”. The research is published in <a href=“https://www.sciencedirect.com/science?ob=ArticleURL&udi=B6VBC-50HN7J5-5&user=906544&coverDate=09%2F30%2F2010&rdoc=1&fmt=high&_orig=search&sort=d&docanchor=&view=c&acct=C000047747&version=1&urlVersion=0&userid=906544&md5=58416dead157c9d3187318687ddacd58”Quaternary Science Reviews.

But why didn’t the mammoths just adapt? “It took a couple of millions of years for the mammoth lineage to evolve through to the woolly mammoths adapted to the cold and grassland conditions,” says Huntley. “A few thousand years would be insufficient time for a large animal like the mammoth with slow regeneration time to adapt quick enough.”

In fact, the woolly mammoth’s mouthparts were specially adapted for feeding on grass, with studies showing that it had evolved into two groups by around 40,000 years ago (see ‘Woolly mammoth family tree grows a new branch’).

Yet humans aren’t quite off the hook. “Our results show that a warming climate about 20,000 years ago would have put a lot of environmental stress on mammoths and other megafauna,” says Allen. “But there is no doubt that humans hunted mammoths. And as the climate warmed, human hunting may have led to the final demise of an already environmentally stressed species.”

The author is a British Science Association Media Fellow.

Image: Natural History Museum

As the appeal for the Pakistan flood victims continues, the UN secretary general Ban Ki-moon has urged the world to respond to the escalating humanitarian crisis (see BBC). The official number of people affected has increased to 20 million people. After Nature first reported on the crisis (see Pakistan’s floods: is the worst still to come?), there have been fresh flood warnings and the situation for the flood victims appears to be worsening.

In the south-eastern region of the country the population are facing a second surge of floodwaters which continue to swell in Sindh and Balochistan provinces. On 13 August 300,000 people were evacuated from the Jacobabad district, Sindh province. Monitoring the flood waters, the Pakistan Meteorological Department have reported increased inflows and discharge at the Guddu and Sukkur barrages built across the Indus River for controlling irrigation supplies. “It is feared that…..the arrival of second flood wave can create extreme pressure on Sukkur barrage and other irrigation infrastructure around” states the Flood Forecasting Division of the Pakistan Meteorological Department. Embankments also appear to be in a vulnerable condition with some breaching in places.

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Why have we seen two decades of static emissions in France? A report from France’s ministry of sustainable development states that between 1990 and 2007 France carbon emissions have not declined. This is a little puzzling given that France is signed up to the Kyoto Protocol, an environmental treaty binding 37 countries to reduce emissions by 2012. It is still further perplexing when you consider France has been championing nuclear power since the 1970’s and relies heavily on this ‘clean’ energy for over 75% of it’s electricity, according to IAEA statistics. With 58 nuclear power reactors in operation across the country, France has more reactors than any other country except the United States. So if France relies so little on carbon dioxide-producing fuels for energy then why haven’t the French managed to bring down their emissions of the greenhouse gas in recent years? WIth crunch time for the Kyoto protocol looming, it’s worth asking what has happened.

According to the ministry, the static emissions are due to an increase in production and consumption offseting gains in efficiency. “If there had been zero economic growth during the same period, carbon dioxide output would have decreased by more than 30%,” Michele Pappallardo, commissioner for sustainable development, told (AFP.

In-fact, since 2007 there are signs that France is back on track to meeting its Kyoto obligations. Between 2007 to 2009, France’s output of Kyoto gases went down by 10%. And looking at just the energy sector, France has recently outperformed its European neighbours in bringing down its emissions.

But then, on the other hand, 2009 was a year when global emissions of carbon dioxide levelled off for the first time since the 1992 recession, according to the Netherlands Environmental Assessment Agency in Bilthoven (see Nature’s article here under ‘Emissions report’). And we must keep all of this in perspective. As a report in Climate Change (doi: 10.1007/s10584-010-9914-6) reminds us there are error bars of 5-10% associated with calculations of countries emissions because emissions are calculated indirectly. So how do we know that any claim of a reduction of less than 10% is real?

In a 26 July report on energy policies by the International Energy Agency (IEA), the French government pledged to “decrease CO2 emissions by 75% by 2050 and to reduce greenhouse gas (GHG) emissions in the transport sector to 1990 levels by 2020”. The IEA has welcomed France’s commitment to combating climate change and the IEA Executive Director Nobuo Tanaka told AFP these goals were “both ambitious and encouraging”. In 2012, observers will be able to see how far France has progressed towards its goals, and if the other 36 industrialised countries that are signatories to Kyoto have fared any better in keeping their promises.