The planet goes haywire Fires and floods, heatwaves and hurricanes - it's been a year of extreme weather. And there's more on the way as global warming kicks in, warns John Vidal Friday August 27, 2004
The Guardian
June was cold, the wettest in Britain for 100 years. At one point, it rained non-stop for more than 58 hours in London, the longest downpour ever recorded in the city. The result was severe flooding throughout the south-east. July, too, was miserable and August was "exceedingly cool, wet and windy" with strong gales, storm damage and a rotten harvest. Scotland shivered.
This was not the lost summer of 2004, but of 1903, well before global warming was ever considered as even a minor player in the world's climates.
There will always be freak weather and temperature and rainfall extremes, but what is extraordinary is that very wet summers such as those of 1903 or 2004, as well as intense heatwaves, storms and droughts, are coming thicker and faster as the world heats up. Ten of the past 14 years have been the hottest recorded, and this is linked by scientists to a rapid rise in levels of greenhouse gas concentrations in the atmosphere - which according to ice core samples tested in the Antarctic, are the highest in 440,000 years and still rising.
Almost all climate scientists, atmospheric chemists and oceanographers say the greenhouse effect has arrived and that we should expect more droughts, hurricanes, flash floods, forest fires and giant storms. The kind of extreme weather that happened once in 100 years, they say, could soon take place every 20 years.
There's plenty of evidence that 2004 is falling into this pattern. There have been major fires in southern France, California, Greece, Ireland, Nicaragua and Alaska, where five million acres have been burning. Drought is affecting large areas of east and southern Africa and there have been intense heatwaves in Spain, Portugal, Japan, and Australia.
But 2004 may be remembered for its floods. Just eight months into the year, Bangladesh, and to a lesser extent India and Nepal, have had some of the severest seen in decades, with tens of millions made homeless. Less noticed have been major floods in Hungary, Vietnam, Kenya, Romania, Lagos, Nicaragua, Iran, Siberia, Bosnia and Papua New Guinea. Meanwhile, 17,000 people needed help after huge snowstorms in the Andes and Korea, and there were heavy falls in unlikely countries such as southern Greece, Jordan and Syria.
Last week the European environment agency produced evidence that Europe was warming faster than expected and that the number of natural disasters had more than doubled in the past decade. Last year's pan-European drought cost 20,000 lives and billions of euros and the later floods affected at least 600,000. The agency, which said that most European glaciers were in fast retreat, warned people to expect more flash floods, mudslides, storms and droughts.
Happily, fewer people have died as a result of extreme weather this year. Last year was one of the worst on record, with the Red Cross estimating that up to 700 "natural disasters" claimed 50,000 lives, almost five times as many as in in 2002. Heatwaves in India, Bangladesh and Pakistan took temperatures up to 50C (122F). In China floods along the Huai and Yangtze rivers swept through 650,000 homes.
The economic cost of extreme weather is soaring. This month's Hurricane Charley caused £10bn of damage in the US. Typhoons in China and Taiwan have also caused enormous losses. Last year's losses worldwide topped £34bn.
But the most unusual weather event in 2004 could have been the 90mph hurricane that hit Catarina in southern Brazil in March. Hurricanes have never been recorded in the southern Atlantic, because the atmosphere does not provide enough "spin" near the surface to get them started and winds higher in the atmosphere tend to shear off any that threaten to form.
Whether it was a true freak of nature or what we can expect with global warming is hotly debated. Climate change scientists in Britain have predicted for some time that such unprecedented events in the south Atlantic would one day be a possibility. But few believed it would happen so soon.
New jaw grown on patient's back
The new bone was grown in a muscle on the patient's backA German man has been able to eat his first proper meal in nine years after surgeons rebuilt his face using a pioneering jaw-bone graft.
The 56-year-old man - who tucked into bread and sausages - had only been able to eat soft food and soup since part of his jaw-bone was removed due to cancer.
University of Kiel researchers "grew" a replacement jaw-bone in a muscle in the patient's back and grafted it in place.
The procedure, previously only tried on animals, was detailed in The Lancet.
The operation took place nine weeks ago, and the patient can now eat steak - but it has to be cut up for him because he has no teeth to bite through the meat.
The patient says he now wants a set of teeth fitted, so he can eat his steak before it gets cold. Doctors say he could get them next year.
3D scans
In cases such as his, surgeons usually take a piece of bone from elsewhere in the body, often the thigh, to repair the jaw.
But this damages the bone in that part of the body, which can itself lead to serious illness.
A patient who had previously lost his mandible through the result of a destructive tumour can now sit down to chew his first solid meals in nine years
Dr Stan Gronthos, Institute of Medical and Veterinary Science, Adelaide, Australia In this case, the patient's jaw had been bridged with a 7cm titanium reconstruction plate since his initial operation.
He was also taking the blood-thinning drug warfarin for an aortic aneurysm, which meant the traditional bone graft method carried a risk of post-operative bleeding.
So it was decided to attempt the new technique.
After taking a 3D computer tomography (CT) scan of the patient's head, they used computer aided design to recreate the missing portion of the jaw-bone (mandible).
The design was used to construct a teflon model, which was then covered with a titanium cage.
The teflon was then removed, and the cage filled with bone mineral blocks, coated with bone marrow and a protein which accelerates bone growth.
The transplant was then implanted into the latissimus dorsai muscle, below the right shoulder blade.
Doctors monitored its development, and CT scans showed new bone was forming.
After seven weeks of growth, the graft was removed, along with a flap of muscle containing blood vessels.
It was then attached to the stumps of the patient's original lower jaw.
The transplant enabled the patient to chew again, and within four weeks he was able to eat solid foods.
'Quality of life'
The researchers, led by Dr Patrick Warnke of the Department of Oral and Maxillofacial Surgery at the University of Kiel, say there is a need for greater understanding about the long-term effects of the procedure.
Writing in The Lancet, they said: "The exciting nature of the result achieved in this patient to date has prompted our group to extend this trial.
"For us to draw firm conclusions, an extended period of follow-up is necessary."
But Dr Warnke told BBC News Online he hoped the procedure could help many other patients, adding: "In addition to helping patients such as this man, we hope it could be used in orthopaedic surgery."
He said implanting the cage into the patient's muscle meant his own tissue developed around it.
"Because it was his own tissue, we don't expect any problems of rejection."
He added: "It was a very successful operation, because when we fitted it to his existing jaw, it was a very good fit, We didn't have to make a lot of changes."
Dr Stan Gronthos, of the division of haematology at the Institute of Medical and Veterinary Science in Adelaide, Australia, said the German research proved this technique could help patients with damaged jaw-bones.
He wrote in The Lancet: "Meanwhile, as the debate continues, a patient who had previously lost his mandible through the result of a destructive tumour can now sit down to chew his first solid meals in nine years, courtesy of a new mandible-like structured implant, resulting in an improved quality of life for that individual."
Scaled-Up Darkness
Could a single dark matter particle be light-years wide?
By George Musser UNIVERSITY OF CALIFORNIA, BERKELEY/KECK OBSERVATORY
SMALL GALAXIES such as NGC 3109 are rarer and less compacted than they would be if matter clumped freely, perhaps because colossal particles that might be the universe's "missing mass" resist clumping.In 1996 Discover magazine ran an April Fools' story about giant particles called "bigons" that could be responsible for all sorts of inexplicable phenomena. Now, in a case of life imitating art, some physicists are proposing that the universe's mysterious dark matter consists of great big particles, light-years or more across. Amid the jostling of these titanic particles, ordinary matter ekes out its existence like shrews scurrying about the feet of the dinosaurs.
This idea arose to explain a puzzling fact about dark matter: although it clumps on the vastest scales, creating bodies such as galaxy clusters, it seems to resist clumping on smaller scales. Astronomers see far fewer small galaxies and subgalactic gas clouds than a simple extrapolation from clusters would imply. Accordingly, many have suggested that the particles that make up dark matter interact with one another like molecules in a gas, generating a pressure that counterbalances the force of gravity.
The big-particle hypothesis takes another approach. Instead of adding a new property to the dark particles, it exploits the inherent tendency of any quantum particle to resist confinement. If you squeeze one, you reduce the uncertainty of its position but increase the uncertainty of its momentum. In effect, squeezing increases the particle's velocity, generating a pressure that counteracts the force you apply. Quantum claustrophobia becomes important over distances comparable to the particle's equivalent wavelength. Fighting gravitational clumping would take a wavelength of a few dozen light-years.
What type of particle could have such astronomical dimensions? As it happens, physicists predict plenty of energy fields whose corresponding particles could fit the bill--namely, so-called scalar fields. Such fields pop up both in the Standard Model of particle physics and in string theory. Although experimenters have yet to identify any, theorists are sure they're out there.
Cosmologists already ascribe cosmic inflation, and perhaps the dark energy (distinct from dark matter) that is now causing cosmic acceleration, to scalar fields. In these contexts, the fields work because they are the simplest generalization of Einstein's cosmological constant. If a scalar field changes slowly, it resembles a constant, both in its fixed magnitude and in its lack of directionality; relativity theory predicts it will produce a gravitational repulsion. But if the field changes or oscillates quickly enough, it produces a gravitational attraction, just like ordinary or dark matter. Physicists posited bodies composed of scalar particles as long ago as the 1960s, and the idea was revived in the late 1980s, but it only really started to take hold four years ago.
Two leaders of the subject are Tonatiuh Matos Chassin of the Center for Research and Advanced Studies in Mexico City and Luis Ureña López of the University of Guanajuato. At a workshop at the Central University of Las Villas (UCLV) in Cuba in June, they described how scalar particles can reproduce the internal structure of galaxies: when the particles clump on galactic scales, they overlap to form a Bose-Einstein condensate--a giant version of the cold atom piles that experimenters have created over the past decade. The condensate has a mass and density profile matching those of real galaxies.
That inflation, dark energy and dark matter can all be laid at the doorstep of scalar fields suggests that they might be connected. Israel Quiros of UCLV argued at the workshop that the same field could account for both inflation and dark energy. Other physicists have worked on linking the two dark entities. "As my senior colleagues used to say, 'You only get to invoke the tooth fairy once,'" says Robert Scherrer of Vanderbilt University. "Right now we have to invoke the tooth fairy twice: we need to postulate a yet to be discovered particle as dark matter and an unknown source for dark energy. My model manages to explain both with a single field."But all these models suffer from a nagging problem. Because the wavelength of a particle is inversely proportional to its mass, the astronomical size corresponds to an almost absurdly small mass, about 10-23 electron volts (compared with the proton's mass of 109 electron volts). That requires the laws of physics to possess a hitherto unsuspected symmetry. "Such symmetries are possible, although they appear somewhat contrived," says physicist Sean Carroll of the University of Chicago. Moreover, the main motivation for big particles--their resistance to clumping--has become less compelling now that cosmologists have found that more prosaic processes, such as star formation, can do the trick. Still, as physicists cast about for some explanation of the mysteries of dark matter, it is inevitable that some pretty big ideas will float around.
Brain may produce its own antipsychotic drug
09:30 30 August 04
Exclusive from New Scientist Print Edition.
A cannabis-like substance produced by the brain may dampen delusional or psychotic experiences, rather than trigger them.
Heavy cannabis use has been linked to psychosis in the past, leading researchers to look for a connection between the brain's natural cannabinoid system and schizophrenia.
Sure enough, when Markus Leweke of the University of Cologne, Germany, and Andrea Giuffrida and Danielle Piomelli of the University of California, Irvine, looked at levels of the natural cannabis-like substance anandamide, they were higher in people with schizophrenia than in healthy controls.
The team measured levels of anandamide in the cerebrospinal fluid (CSF) of 47 people suffering their first bout of schizophrenia, but who had not yet taken any drugs for it, and 26 people who had symptoms of psychosis and have a high risk of schizophrenia.
Compared with 84 healthy volunteers, levels were six times as high in people with symptoms of psychosis and eight times as high in those with schizophrenia.
"This is a massive increase in anandamide levels," Leweke told the National Cannabis and Mental Illness Conference in Melbourne, Australia, last week. And that is just in the CSF. Levels could be a hundred times higher in the synapses, where nerve signalling is taking place, he says.
Cause or effect
But were the high anandamide levels triggering the psychotic symptoms or a response to them? Leweke and his colleagues found, to their surprise, that the more severe people's schizophrenia was the lower their anandamide levels.
The team's theory is that rather than triggering psychosis, the substance is released in response to psychotic symptoms to help control them. People with the worst symptoms might be unable to produce sufficient anandamide to prevent them.
At some point in their lives, between 5 and 30 per cent of healthy people have had symptoms such as delusions or hallucinations, which can be triggered by something as simple as sleep deprivation. "All of us are potentially psychotic," says David Castle of the University of Melbourne. So for the body to have a system that prevents these experiences getting out of hand makes sense, he says.
The new findings suggest antipsychotic drugs could be developed that target the anandamide system, but it will not be simple. The active ingredient in cannabis, THC, binds to anandamide receptors.
But people with schizophrenia who use cannabis actually have more severe and frequent psychotic episodes than those who do not. This may be because THC makes anandamide receptors less sensitive.
Leweke's team also found anandamide levels lowest in people with schizophrenia who used cannabis more frequently, suggesting it may disrupt the system in other ways too. Up to 60 per cent of people with schizophrenia use cannabis.
A study by Castle, also reported at the Melbourne meeting, has found that people use the drug to get rid of unpleasant emotions associated with the disease such as anxiety and depression.
