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Freezing UK winter Prof Yash
Pal THIS UNIVERSE US regulators ill-equipped to decide on bio-crops
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Freezing UK winter
It was the coldest winter in England since 1963 — the coldest in Scotland since 1914 — and weeks of ice, snow and sub-zero temperatures from last December to March defied predictions by climate-change scientists of milder, wetter winters. So what happened? One theory suggests that last winter’s cold temperatures were part of a pattern that is set to continue because of a complex interaction between the Sun’s magnetic field and the high-altitude jet stream which dominates Britain’s weather system. The jet stream normally brings mild, damp westerly winds over Britain during winter but this year it went into “blocking” mode, sweeping back on itself and allowing a bitterly cold north-east wind to blow over the country, bringing ice and snow with it. Scientists have found a link between blocking changes to the jet stream that result in colder winters and variations in the “activity” of the Sun, as measured by alterations in its magnetic field. This could mean that the UK can expect more cold winters than usual in the coming decade, despite global warming. The researchers behind the controversial idea emphasised that their findings do not contradict the scientific consensus on man-made climate change. They said that global warming is still set to dominate the world’s climate, but that the relatively small region of Britain and north-west Europe could nevertheless be in line for more frequent, colder-than-expected winters, just like the last one. “The winter we’ve just had fits the trend very nicely and it was actually last winter that made us look into this,” said Professor Mike Lockwood, a solar physicist at the University of Reading and the Rutherford Appleton Laboratory in Didcot, Oxfordshire, who led the study published in the journal Environmental Research Letters. “We have found an association between variations in solar activity and changes in the temperature records of central England over the past few decades. This year’s winter in the UK has been the 14th coldest in the last 160 years and yet the global average temperature for the same period has been the fifth highest. We have discovered that this kind of anomaly is significantly more common when solar activity is low.” The Sun has a roughly 11-year cycle and at its height the solar magnetic field is active and sunspots appear on the Sun’s surface. But over recent years the Sun has entered an unusually dormant phase, with few sunspots and very low magnetic activity. Professor Lockwood said one effect of this low activity was that the normally high ultraviolet light from the Sun was lower than usual. This means there is less heating of the upper stratosphere over the equator, where ultraviolet light causes the creation of ozone. This has a knock-on effect on the jet stream. It means the normal inhibition on the formation of a blocking system is lifted and the jet stream is likely to curl back on itself over Britain, bringing colder winds from the north-east to replace the damp, mild maritime air that normally comes from the south-west. — By arrangement with The Independent
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THIS UNIVERSE While putting water in a frying pan, I added tea leaves in it (right at the beginning of the process of boiling). The tea particles first went down then came up to the surface of water or vice verse. Then they all clustered at the top. Why? I do not know how you handled the frying pan (Incidentally, you are a bit crazy making a heavenly brew in a frying pan. You are insulting an almost religious ritual). Anyway your curiosity is still justified. The tea leaves originally float because they have some air trapped in them. After these bubbles are released the leaves go down. When boiling starts, particularly in a frying pan, the steam originating at the bottom first condenses around some of them and they come up. After the tea is made you must have put some sugar and milk and stirred up the brew with a spoon. That gives a rotational motion leading to a centrifugal force on the motion to the liquid. This is reduced near the walls of the pot and at the bottom, due to friction. This is what leads to clustering of the tea leaves in the centre. This will collect at the bottom of the cup in the centre. This question was first discussed by Einstein in a paper written in 1926. I am copying below an extract from his paper: “I begin with a little experiment which anybody can easily repeat. Imagine a flat-bottomed cup full of tea. At the bottom there are some tea leaves, which stay there because they are rather heavier than the liquid they have displaced. If the liquid is made to rotate by a spoon, the leaves will soon collect in the centre of the bottom of the cup. The explanation of the phenomenon is as follows: the rotation of the liquid causes a centrifugal force to act on it. This in itself would give rise to no change in the flow of the liquid if the latter rotated like a solid body. But in the neighbourhood of the walls of the cup, the liquid is restrained by friction, so that the angular velocity with which it rotates is less there than in other places nearer the centre. In particular, the angular velocity of rotation, and therefore the centrifugal force, will be smaller near the bottom than higher up. The result of this will be a circular movement of the liquid of the type illustrated in Fig. 1 which goes on increasing until, under the influence of ground friction, it becomes stationary. The tea leaves are swept into the centre by the circular movement and act as proof of its existence.” |
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US regulators ill-equipped to decide on bio-crops Kremer’s lab is housed at the University of Missouri and is literally in the shadow of Monsanto Auditorium, named after the $11.8 billion-a-year agricultural giant Monsanto Co. Based in Creve Coeur, Missouri, the company has accumulated vast wealth and power creating chemicals and genetically altered seeds for farmers worldwide. But recent findings by Kremer and other agricultural scientists are raising fresh concerns about Monsanto’s products and the Washington agencies that oversee them. The same seeds and chemicals spread across millions of acres of U.S. farmland could be creating unforeseen problems in the plants and soil, this body of research
shows. “This could be something quite big. We might be setting up a huge problem,” said Kremer, who expressed alarm that regulators were not paying enough attention to the potential risks from biotechnology on the farm, including his own research. Concerns range from worries about how nontraditional genetic traits in crops could affect human and animal health to the spread of herbicide-resistant weeds. Biotech crop supporters say there is a wealth of evidence that the crops on the market are safe, but critics argue that after only 14 years of commercialised GMOs, it is still unclear whether or not the technology has long-term adverse effects. But whatever the point of view on the crops themselves, there are many people on both sides of the debate who say that the current U.S. regulatory apparatus is ill-equipped to adequately address the concerns. Indeed, many experts say the U.S. government does more to promote global acceptance of biotech crops than to protect the public from possible harmful consequences. The World Health Organization has not taken a stand on biotech crops generally, simply stating “individual GM foods and their safety should be assessed on a case-by-case basis.” With a growing world population and a need to increase food production in poor nations, confidence in the regulatory system in the leading biotech crop country is considered critical. Farmers around the world seem to be embracing biotech crops that have been altered to resist bugs and tolerate weed-killing treatments while yielding more. According to an industry report issued in February, 14 million farmers in 25 countries planted biotech crops on 330 million acres in 2009, with the United States alone accounting for 158 million
acres. — Reuters
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Trends CAPE CANAVERAL, Florida: A problem with a cooling system aboard the International Space Station may prompt NASA to extend shuttle Discovery’s mission for an unplanned fourth spacewalk, NASA officials said on Wednesday. During three previous outings, spacewalking astronauts Rich Mastracchio and Clay Anderson installed a new 1,700-pound ammonia cooling system and packed up an old unit for return to Earth and refurbishment.
Birds aren’t in it for love
TORONTO: It’s not all love in the avian world, where divorce, child abandonment and marrying up are part of everyday life. “The Bird Detective,” to be published in Canada this week, dispels the love-bird myth that birds pair up for life, and paints a picture instead that includes adultery and the pursuit of comfort.
More evidence of water on moon
WASHINGTON: Ice deposits at least 6 feet thick can be found in some small craters on the moon, researchers reported Monday in one of two studies showing more evidence of water on the moon and Mars. The second study suggested that ice has recently melted and re-frozen on Mars, widening some of the characteristic gullies on its surface.
Diet can cut Alzheimer’s risk
CHICAGO: A diet rich in olive oil, nuts, fish, poultry and certain fruits and vegetables may have a powerful effect at staving off Alzheimer’s disease, researchers reported on Monday. People who ate nutrients specifically selected for brain health had a 40 percent lower risk of developing Alzheimer’s disease compared with others, Yian Gu, an Alzheimer’s disease researcher at Columbia University in New York and colleagues found.
Wild birds could spread avian flu
WASHINGTON: Wild ducks that are immune to the effects of H5N1 avian influenza could be spreading the virus far and wide, U.S. government researchers said on Monday. Satellite tracking of migrating northern pintail ducks showed they flew from a bird flu-infected marsh in Japan to nesting areas in Russia, said the scientists from the U.S. Geological Survey and the University of Tokyo
said.
— Reuters
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Robert Kremer, a US government microbiologist who studies Midwestern farm soil, has spent two decades analyzing the rich dirt that yields billions of bushels of food each year and helps the United States retain its title as breadbasket of the world.
Kremer, who works for the U.S. Department of Agriculture’s Agricultural Research Service (ARS), is among a group of scientists who are turning up potential problems with glyphosate, the key ingredient in Monsanto’s Roundup and the most widely used weed-killer in the world.