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Weekly Update: Ecological damage from computers
TOKYO: Computer users should think twice before buying a new machine in order to reduce consumption of natural resources such as fossil fuels and conserve space in landfills, according to a recent United Nations study.
The study, published in October by the Tokyo-based UN University, says that manufacturing one desktop computer requires more than 240 kilograms of fossil fuels, or about 10 times its weight. In contrast, the amount of fossil fuels needed to make cars and refrigerators is roughly equal to their weights, said the report, titled “Computers and the Environment: Understanding and managing their impacts.”— APP/AP
Enigma of Uranus solved at last
PARIS: Uranus has puzzled scientists ever since the probe ‘Voyager 2’ did a flyby in 1986 and found that its magnetic field appeared to break the planetary rulebook.
The evidence from Earth, Jupiter and Saturn determined that a planet’s magnetic field should be like that of a bar magnet, with a north and south pole that runs roughly along the sphere’s rotational axis.
But Uranus — and Neptune, too, Voyager found — is radically different. Their magnetic fields are tipped over (the north-to-south line lies midway to the equator or even closer) and there are two north and two south poles, as if the field were produced by two bar magnets.
The reason for this, according to a new theory published on Thursday in the British journal Nature, is: The underlying structures of Uranus and Neptune are radically different from what was previously assumed about these cold, distant planets.
Planetary magnetic fields are created like a dynamo: beneath the planet’s surface, there is an electrically conductive fluid, which is driven around by an energy source.
Where Neptune and Uranus differ, the new study says, is that even though they are gas giants, their interior structure is different from those of Jupiter and Saturn.
It suggests that these two outer planets may have only a thin layer of metallic convecting fluid.
This has a big effect on the magnetic field, limiting it to a thin “shell” just under the gassy hydrogen surface. That phenomenon may also cause the field to be tipped on its side compared to the rotational axis and also inflict the “quadrupole” effect.
The study’s co-authors are Jeremy Bloxham and Sabine Stanley of Harvard University, whose computer model of the planets’ interior strongly replicates the strange magnetic fields detected by Voyager 2.— AFP
Miniature heartbeat monitor
AUCKLAND: New Zealand scientists unveiled a tiny radio-based device that can monitor a patient’s heartbeat without the need to be wired up to a machine, the New Zealand Herald reported on Wednesday.
Developed by Auckland University, the system lets hospital patients go to the bathroom or for a short walk without losing contact with machines that monitor their heart, temperature and other crucial functions, the report said.
The small matchbox-sized device is connected to two sensors on the body recording nerve activity and uses mobile telephone Bluetooth wireless to transmit the data to a monitor machine, the university said on its website. — APP/AFP
One in eight of the world’s birds faces extinction
JOHANNESBURG: One in eight of the world’s birds face extinction, fuelled by unchecked agricultural expansion and unsustainable forestry, specially in the tropics, according to a report by Birdlife International.
“The State of the World’s Birds 2004” said the alarming statistics showed that “our global environment is under serious strain with a massive and still increasing haemorrhage of biodiversity”.
It said one in eight of the world’s birds — or 1,211 species — face extinction. Of these, 179 species are critically endangered, 344 face very high risk of extinction and 688 are listed as vulnerable.
It said 966 species of globally threatened birds had populations of less than 10,000, while 502 species had populations less than 2,500. About 77 species had populations lower than 50.
The study said nearly all the world’s countries and territories hosted one or more globally threatened bird species. But some regions held particularly high densities of threatened species.
The report said uncontrolled farming had played havoc with biodiversity and could ring the death knell for many bird species.
The study called for coordinating environmental actions across nations, and setting up local groups to protect bird species from dying out. —AFP
World’s highest weather station on Mount Everest
BEIJING: China is to build the world’s highest weather station at an altitude of 5,300 metres on Mount Everest, state media reported on Tuesday. The unmanned station will be completed within a year and will record temperature, humidity, air pressure, rainfall and wind speed, said Wang Jianshe, from the Tibet Weather Bureau in Lhasa.
The unpredictable weather on Mount Everest, the world’s highest peak, is currently monitored by a meteorological station 90 kilometres away, raising the possibility of errors in forcasting for the treacherous mountain.
Wang, cited by the Xinhua news agency, said the station was part of a drive to build an automatic monitoring network with 41 stations across Tibet.
Some 20-odd expeditions each year seek to conquer the mountain. At least 72 people have died trying to reach the summit.— AFP
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