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Startling erosion of Antarctic ice
The Antarctic ice sheet, which contains 90 per cent of the world’s ice, has lost significant mass in the past few years. The discovery comes as a surprise to scientists, who thought that the continent would gain ice this century because of increased snowfall in a warming climate.
A research team from the University of Colorado used satellite data to estimate that the ice sheet is losing up to 36 cubic miles of ice every year. By comparison, a city the size of Los Angeles uses one cubic mile of fresh water every year.
“This is the first study to indicate the total mass balance of the Antarctic ice sheet is in significant decline,” said Prof Isabella Velicogna of the Cooperative Institute for Research in Environmental Sciences (Cires).
Most of the ice loss measured by Prof Velicogna — around 35 cubic miles — came from the West Antarctic ice sheet. According to the British Antarctic Survey, if the West Antarctic ice sheet — which is about eight times smaller in volume than the East Antarctic ice sheet — melted completely, global sea levels would rise by more than six metres (20 ft).
At twice the size of Australia, Antarctica is the Earth’s fifth largest continent and contains 70 per cent of its total fresh water resources. An ice sheet covers about 98 per cent of the continent with an average thickness of about 2,000 metres (6,500 ft).
Controlling people remotely
In theory brain implants may control people remotely, although you would not be able to do much useful with them. The news that US researchers have produced a radio-controlled dogfish and plan to extend the technology to sharks raises the question of what the military, which funded the research, want to do it for.
The sharks, with their ability to glide quietly through the water and follow chemical trails would make them ideal stealth spies. But could remote-control be extended to people? The research, by Jelle Atema at Boston University and his team, reported in New Scientist, involved using a series of electrodes implanted in the brains of spiny dogfish to “steer” the animals in a tank. By stimulating the olfactory regions of the brain, the animals followed a “phantom odour” created by the brain stimulation. A 2004 study from a different research group involved stimulating the nerves connected to rats’ whiskers to achieve a similar effect.
So are remote-controlled human killing machines next on the list? No, said Richard Apps, a neurophysiologist at Bristol University. It’s one thing to make a fish move left or right, but a huge leap to making someone perform a complex task against their will. “That’s the world of science fiction.”
Similar research has led to benefits for people though. Surgeons can now stop the debilitating tremors suffered by Parkinson’s disease patients by implanting an electrode deep into their brains.
Huge medical experiment
The world’s biggest medical experiment — an attempt to understand the interaction between genes and the environment in affecting health — will begin shortly amid mounting criticism from scientists that it is a badly designed project of questionable scientific value and likely to give misleading results.
The UK Biobank, a £61 million government-backed project to track participants for several decades, is aimed at understanding how diseases such as cancer, heart disease, diabetes and Alzheimer’s develop in populations. Soon the project will begin recruiting the first of its eventual goal of 500,000 people.
However, many scientists believe the project is a waste of money and will end up as an albatross for the medical research community. “Most (scientists) think that it’s not a terribly good way to spend that amount of money,” said Hilary Rose, a professor of the sociology of science at City University. “What is the public likely to get from it? It’s not very clear what its aims and objectives are.”
Helen Wallace, of the pressure group GeneWatch, which focuses on responsible use of genetic technology, said her biggest concern with Biobank was the project’s design and the lack of “proper discussion” of its relevance to health. She said: “There’s a lot of scientific concern that it will throw up spurious links between genes and diseases and that it won’t deliver the promised benefits to health.”
Cancer chemical in soft drinks
Soft drinks on sale in the UK have been found to contain benzene, a cancer-causing chemical. Benzene is produced when the drinks have the preservative sodium benzoate and vitamin added to them. The two can interact to form the carcinogen.
The Food Standards Agency ordered the soft drinks industry to survey its products last year when tests in the United States found benzene in soft drinks sold there. In tests of 230 products, levels of up to eight parts per billion were found in some drinks.
The legal limit of benzene in drinking water is one part per billion. There are no legal limits on benzene in soft drinks. The brand names of drinks containing benzene have not been made available. — Dawn/The Guardian News Service
Water sources threatened
Declines in rainfall caused by global warming threaten rivers and other local sources of fresh water in densely populated areas of Africa, according to a new study published by Science magazine.
Some of these areas, particularly in southern Africa, already suffer periodic droughts, so further declines in rainfall could have “devastating implications” for people who depend on local water supplies, according to the two authors, Maarten de Wit and Jacek Stankiewicz of the Africa Earth Observatory Network at the University of Capetown.
Other particularly vulnerable areas include a narrow band of territory that stretches from Senegal eastwards to Sudan and crosses several important water bodies that supply populations downriver. — Dawn/IPS News Service
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