Weather Eye

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From The Times

April 26, 2007

Forward springs and long droughts are nothing new

Paul Simons

"The spring is more forward than has been known for many years. It is to be feared, however, that the excessive drought is doing serious injury to grass lands and green crops of all kinds; and in many places there is a great scarcity of water."

This report may sound familiar, but it was written in April 1893 from Appleby parish, Leicestershire, during Britain's longest recorded drought.

Some places that year did not record measurable rain from the end of February to mid-May. Mile End, in East London, broke the UK record for the longest continuous run without rain: 73 days, from March 4 to May 15. The lack of rain, together with hot sunshine, brought thousands of bathers flocking to the seaside from late March onwards. But by May, plants were scorched and huge wildfires broke out on heaths and woodlands.

A recent paper in the Royal Meteorological Society's journal, Weather, reports how this drought came during a dry period called the "Long Drought", lasting about 20 years up to 1910. Some particularly dry winters and springs in lowland England resulted in water restrictions, withered crops, stressed cattle and industrial mills closed down.

So, our run of dry weather is not unique.

From: http://www.timesonline.co.uk/tol/news/weat...icle1706860.ece

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From The Times

April 27, 2007

Rollercoaster brings rain and drought, hail and heat

Paul Simons

Britain may feel like the only place under the spell of unseasonal weather, but elsewhere the elements have behaved even more strangely.

The US has been on a meteorological rollercoaster that has broken a raft of records, from freezing cold and snow, ferocious storms and rains, and now a blistering heat wave – all in the space of two weeks.

In fact, snow is still falling in Colorado. However, Los Angeles has been in the grip of its worst drought since records began there in 1877, although last Friday the first decent shower of the year fell.

Much of Australia is suffering its worst drought in history, but last weekend Sydney was hit by an intense thunderstorm that set off flashfloods across parts of the city. Nearly 100mm (4in) of rain fell, but it did little to help the water shortage.

Recent torrential rains in Morocco also triggered floods, in which four people died. Kuwait, also, was hit by a ferocious storm that brought giant hailstones and extraordinary rainfalls – Kuwait airport reported 302mm (11.9in) of rain in just over a day.

And while the UK bakes in warm sunshine, southern Spain has been lashed by heavy rains and winds that have done enormous damage to the salad crop industry.

But strangest of all, two weeks ago thousands of frogs fell during a shower on a village in Serbia.

From: http://www.timesonline.co.uk/tol/news/weat...icle1711839.ece

From The Times

April 28, 2007

Dust storms threaten to put an end to salad days

Paul Simons: Weather Eye

The rains this week came in the nick of time for many farmers and gardeners. The lack of rain and record temperatures this month had left seedlings perilously close to shrivelling and dying before the showers arrived and saved the day.

Many farmers are planning for climate change by building reservoirs to hold winter rain-water ready to irrigate crops over long dry summers.

This is particularly important in the drier regions, such as East Anglia, where salad-crop growers are irrigating plants already. So far, they are reporting a bumper harvest this spring, with plants advanced two weeks earlier than normal, and the first English-grown iceberg lettuces expected to be cropped early, around May 10.

In fact the lack of rain has helped to keep diseases at bay and improve the crop quality. In contrast, the big salad exporters of southern Spain are having a wretched time with thunderstorms, floods and high winds ruining their harvests.

But with more dry weather on the way in the UK, dust storms could become a threat. The dry, exposed topsoil of the Fens is particularly susceptible to being blown up into clouds of dust by high winds. In March 2002, 17 days without rain were followed by 110km/h (70mph) gales which whipped up huge dust storms across Cambridgeshire and Norfolk that turned the sky dark and made driving dangerous.

From: http://www.timesonline.co.uk/tol/news/weat...icle1717285.ece

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From The Times

April 30, 2007

April's sunshine burns a mark in the record book

Paul Simons: Weather Eye

The sunshine has been glorious this month, despite the recent clouds. The daily hours of sunshine for England and Wales are running about 50 per cent above average, and although the total for the month is not going to break any records, it will be one of the sunniest Aprils on record.

Sunshine measurements have changed in recent years. Previously, a Campbell-Stokes instrument was used, arguably the most elegant of all weather instruments, and easily recognised by its big glass ball. It was invented in Scotland by John Francis Campbell in 1853. He noticed that a glass ball sat in a wooden bowl focused sunlight into such an intense beam it scorched the wood. By making hourly marks on the bowl, a record of the day's sunshine was burnt as the Sun moved through the sky. Stokes later refined this by supporting the glass ball over a strip of card to burn the trace of sunshine.

However, someone had to read the card at the end of each day, and when the Sun was obscured by patchy cloud, the bursts of sunlight tended to burn a blurred trace that could overestimate the amount of sunshine by up to 20 per cent.

The Met Office weather stations now all use an electronic sunshine meter, which is more accurate and sends data automatically, but which is not nearly as attractive.

From: http://www.timesonline.co.uk/tol/news/weat...icle1722908.ece

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From The Times

May 1, 2007

Will May be warm or snowy – as once it was?

Paul Simons: Weather Eye

After a record warm April, what will May bring? The next few days, at least, promise much of the same warm, dry sunny weather for much of the UK. The reason is familiar – a stable block of high pressure remains anchored over the country.

But May can be a deceptive month. Although the hours of daylight are long and the sun is high in the sky, this is not a summer month and the weather can deliver some nasty surprises. The 17th-century writer John Aubrey recorded the return of winter in Wiltshire in the previous century: “Edward Saintlow, of Knighton, Esq. was buried in the church of Broad Chalk, May the 6th, 1578, as appeares by the Register booke. The snow did then lie so thick on the ground that the bearers carried his body over the gate in Knighton field, and the company went over the hedges, and they digged a way to the church porch.”

This snow was especially dramatic because it would have fallen on May 16 in the modern, Gregorian calendar.

However, last month was so warm it is highly unlikely that snow will fall this May – historical records show that it is very rare for May to be colder than April. In fact, a warm May is far more common after a warm April. And, as for summer, June tends to follow on with pleasant temperatures.

From http://www.timesonline.co.uk/tol/news/weat...icle1728928.ece

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From The Times

May 2, 2007

Ionised Earth may spark quake warning light show

Paul Simons: Weather Eye

Last Wednesday a commercial airline pilot reported bright yellow lights shaped like flat discs in the sky near Guernsey. They were also observed by the passengers and by other aircraft.

Paul Devereux, of Moreton-in-Marsh, Gloucestershire, wrote in to point out that they may have been a precursor of the earth tremor that struck off the coast of Dover on Saturday. “Evidence indicates that these exotic light phenomena seem to be related to geophysical processes, one being tectonic strain,” he explains.

After an earthquake in November 1930 in the Idu Peninsula, Japan, scientists collected some 1,500 reports of lights in the sky. These were usually bluish lights, like the rays of the Sun, and at night they could be brighter than moonlight.

In 1968 the first photographs of earthquake lights were taken during masses of earthquakes at Matsushiro, Japan. Thousands of seismic events were being recorded each day and the photos show balls of light and red streaks over the tops of mountains.

One theory is that these lights are created when the enormous pressures in a moving geological fault squeeze the rocks and produce what is called a piezoelectric voltage, turning mechanical energy into electrical charge. An intense electrical field, perhaps 100,000 volts per square metre, ionises the air and produces the glowing lights.

From http://www.timesonline.co.uk/tol/news/weat...icle1733492.ece

From The Times

May 4, 2007

May heat wave shows the changes a decade makes

Paul Simons: Weather Eye

A heat wave in May after a long, dry April during an exceptionally warm start to the year. Sounds familiar?

In fact, this was the weather pattern ten years ago when a severe lack of rain began the previous December. By April showers were almost nonexistent and one water company suggested importing water from France.

Drawing parallels between the weather in different years can be misleading, though. In contrast to the bone-dry winter of 1996-97, last winter was soaking wet, otherwise all the talk now would be turning to hose-pipe bans. And May 1997 had an unexpected sting in its tail, when a plunge of cold polar air sent temperatures tumbling, conveniently timed for the Bank Holiday Monday on the 5th, followed by snow that hit North Wales particularly hard.

But 1997 highlighted a trend in Britain’s climate. The rest of that year and into 1998 produced a 14-month run of warmer than average, or average temperatures, a familiar pattern that has gained pace ever since.

Temperature records fall regularly now, and over the past 12 months they include the warmest July and hottest month recorded, the warmest September, the warmest winter and the warmest April.

With hindsight, the weather of 1997 shows how much climate change has taken grip.

From http://www.timesonline.co.uk/tol/news/weat...icle1744301.ece

From The Times

May 5, 2007

Oak’s reach for the heat leaves ashes in the shade

Weather Eye: Paul Simons

Oak before ash, in for a splash, Ash before oak, in for a soak The old saying is supposed to predict the summer: if the oak comes in to leaf before the ash the summer will be dry, but if the ash leafs first it predicts a wet one.

This year the oaks have left ashes way behind. In fact, this has been the pattern most years now, and shows how Britain’s climate is changing. Oaks are sensitive to temperature and as springtimes grow warmer, the leaves appear earlier. The ash, though, responds more to the hours of daylight to open its leaves, and is now caught in a time warp, trapped in the springtime of years ago.

In the long run the ash is going to suffer – the oaks are off to such an early start they are shading out the ash in woodlands and gradually squeezing them out.

But this was not always the case. In 1736 Robert Marsham, a Norfolk landowner, began recording the first signs of springtime, and his descendants continued the work until the 1950s. Their records show a much closer race between the oak and ash, and also hinted at the origins of the folklore saying. The ash often won in wet-ter weather, possibly because it has shallow roots, while the oak has deeper roots and does much better in drier conditions.

From http://www.timesonline.co.uk/tol/news/weat...icle1750052.ece

From The Times

May 7, 2007

The cold, wet curse of the May Day bank holiday

Paul Simons: Weather Eye

After weeks of warm and often sunny weather, why did this holiday weekend have to turn wet and windy? In fact, many would say that this was bound to happen as the curse of the British Bank Holiday strikes again.

There is something inevitable about it – a good start to the holiday weekend to give a sense of optimism, dashed by a rapid descent into meteorological misery. But does the evidence stack up, that a public holiday weekend is always bad? Since the Early May Bank Holiday was first introduced in 1978, ten of them could be described as reasonably warm, dry and sunny, and the rest mediocre or dreadful.

This is not a very scientific survey, but it is not an impressive record. However, early May is when mild, westerly winds tend to be at their slackest for the year and often can allow colder northerly winds to creep in.

Perhaps a better test is to compare the May holiday weekend to an ordinary weekend. Weather records over the past decade or so reveal that the May Day holiday has enjoyed slightly better weather than the weekends immediately before or after. Temperatures were a touch higher, with more sunshine. But this is a small crumb of comfort for anyone bracing the elements today.

From http://www.timesonline.co.uk/tol/news/weat...icle1756030.ece

From The Times

May 8, 2007

Cypress rings record the sufferings of Jamestown

Paul Simons: Weather Eye

Last week the Queen visited Jamestown, Virginia, for the 400th anniversary of the first permanent English settlement in America. But the pioneering colony came close to catastrophe during one of the worst droughts there for 800 years.

When the colonists arrived they expected to find a lush paradise full of gold and silver. Instead they faced swampy land, mosquitoes, brackish water, disease and a savage winter. But examination of ancient cypress trees in the area revealed that the colonists also endured a seven-year drought.

The annual growth rings in wood show how well trees grow each year, and droughts show up as very narrow growth rings. The long-lived cypress trees provide a climate record going back to 1200, and the Jamestown drought of 1606-12 was exceptional.

This goes a long way toward explaining the failed harvests, famines and foul water of the “starving years”, as they were known, which also sparked conflict with the Powhatan Indians, who suffered their own food shortages. The period was so devastating that more than half the colonists died, and the settlement was briefly abandoned. But as the survivors set sail for England, they were met by a new convoy sailing in to Jamestown and were persuaded to stay. The introduction of tobacco growing revived the fledgeling colony’s fortunes, and the settlement thrived.

From http://www.timesonline.co.uk/tol/news/weat...icle1760239.ece

From The Times

May 9, 2007

Jet stream brings us one of Buchan’s wet spells

Weather Eye Paul Simons

Just as the grass was turning yellow and flower beds beginning to droop, the early May Bank Holiday was drenched with heavy rain.

Those downpours and gusting winds marked a turning point in the weather, which is likely unsettled to remain for some time. The dry weather over the past few weeks was a consequence of a stable area of high pressure over the UK and much of Northern Europe. As a boulder splits the flow in a river, the anticyclone blocked the path of Atlantic depressions and sent the wet weather on a wide detour to the far north or to the south of Europe. But that blocking high-pressure system has now shifted, allowing the jet stream – a ribbon of fast wind a few miles high – to bring clouds, rain and wind to the UK.

Perhaps this is not a surprise, because mid-May is often the time of year for the weather to change track. The eminent Victorian meteorologist Alexander Buchan analysed the climate of his native Edinburgh in the late 1800s and found certain times of the year regularly warmer or colder than expected.

These became known as Buchan’s spells, and one was May 9-14, which was often blighted by bad weather. This coming Sunday is the centenary of Buchan’s death.

From http://www.timesonline.co.uk/tol/news/weat...icle1763876.ece

From The Times

May 10, 2007

Imperial Britain gave metrication the chop

Weather Eye: Paul Simons

Pounds and inches have been saved for the nation – the European Commission has said that imperial measurements can be used alongside the metric system (The Times, May 9).

But this leaves our measurements in a mess. In weather forecasts, we have millimetres of rain, but miles per hour for wind. Temperatures are largely celsius, but 100 degrees fahrenheit sounds more dramatic than 38C.

In fact, the metric system was introduced in France in the Revolution to sort out a chaotic jumble of different measures used in different regions.

Two French astronomers, Delambre and Mechain, based the metre on a ten-millionth of a meridian drawn from the North Pole to the Equator, a 90-degree slice of the Earth’s circumference. But no one had ever been to the North Pole, so the survey was impossible. Instead, they measured a segment of a meridian and calculated the rest. By sheer luck, there was an ideal line from Dunkirk to Barcelona, covering about a tenth of the distance required. But in revolutionary France the survey work was dangerous, the scientists stood on top of high points with their surveying instruments and were often mistaken as spies. Eventually in 1799, after seven years’ work, the length of the metre was confirmed. But the British rejected any ideas from the French Revolution, and metrication has been a problem ever since.

From http://www.timesonline.co.uk/tol/news/weat...icle1769339.ece

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From The Times

May 11, 2007

A milder May should keep the Ice Saints at bay

Weather Eye: Paul Simons

This is a nerve-racking time of year for gardeners looking to plant delicate plants outdoors. Frosts can strike in May, although they happen less frequently than in the past, when frosts in mid-May were so well known they were given their own saints.

The "Ice Saints" Mamertus, Pancras, Servatius and Boniface were celebrated on feast days from today to May 14. Across much of Northern Europe these saints were feared by farmers for the damage they could inflict on ground crops, vines and fruit trees. Little is known about the Ice Saints, except that the weather records seem to bear out their reputation. In the past century, about 60 per cent of the years had unusually cold spells during the middle of May, including snow on nine occasions. The UK's lowest May temperature, minus 9.4C (15F), occurred on May 11, 1941, in Thetford, Norfolk, during eight successive nights of frost. But perhaps the worst of the Ice Saints' work struck in May, 1955. Frosts began on May 10, and grew so cold that a week later a blizzard tore through the Midlands and the South; even London had three hours of snow during the night.

This May conditions should be sufficiently mild to keep the Ice Saints at bay.

From: http://www.timesonline.co.uk/tol/news/weat...icle1774770.ece

From The Times

May 12, 2007

Tornado whips up fears for US hurricane season

Paul Simons: Weather eye

The weather in the US has taken an ominous downturn. Last Friday, a ferocious tornado obliterated the town of Greensburg, Kansas, with winds estimated to be greater than 320km/h (200mph). Eleven people were killed and 95 per cent of the buildings destroyed.

The Kansas tornado drew its strength from a particularly violent clash of warm, humid air from the south and drier air from the deserts of New Mexico and Arizona. The humid air burst upwards, driven along by strong high-altitude winds, and erupted into a rotating thunderstorm.

This was one of a series of thunderstorms that swept the Plains. Because they moved slowly, the storms brought immense downpours that set off flooding, and thousands of people fled their homes along the Missouri River. In a chilling reminder of the devastation of New Orleans by Hurricane Katrina, several levee flood defences broke on the river and waters submerged the town of Big Lake, Missouri.

This Wednesday, the first named storm of the year, Andrea, appeared off the southeast coast of the US. "Andrea" was a subtropical storm rather than a full-blown hurricane and presented little danger. But its early appearance alarmed many experts, who fear the coming hurricane season will be extremely active, in contrast to last year's unexpectedly quiet season.

From: http://www.timesonline.co.uk/tol/news/weat...icle1779382.ece

From Times Online

May 14, 2007

Britain warms to the taste for home-grown olives

Paul Simons: Weather Eye

An olive grove basking under scorching hot sunshine, in parched soil, after weeks of drought. It sounds like a scene from the Mediterranean, but it is Honiton, South Devon, where Britain's first olive grove was planted by an enterprising farmer last year.

The olive trees were imported from Tuscany, where they experience frost and snow in winter and high temperatures in summer. Drainage on the heavy Devon soil had to be improved, because olive trees are used to growing in thin, rocky soils. But with the rapidly warming climate, it is hoped the first commercial British olive crop will be harvested in a few years' time.

Perhaps even more surprising, two commercial olive groves have been planted much further north, in Wales and Shropshire. Three hundred Italian olive trees were planted at Wroxeter Roman Vineyard, near Shrewsbury, and the first Welsh olive grove was begun in Anglesey.

Faced with rising temperatures, farmers have to plan tree crops that can withstand a hotter climate. Already, the UK growing season has lengthened by about a month since 1900. By mid-century, maximum temperatures in southern counties will break through the 40C (104F) level, and by 2080, the South East could be as hot as Bordeaux is now.

From: http://www.timesonline.co.uk/tol/news/weat...icle1785059.ece

From The Times

May 15, 2007

Giant hailstones brought death and chaos in 1697

Paul Simons: Weather Eye

If this month's weather has come as a shock, worse conditions have struck May in the past.

Hailstorms of incredible savagery blighted May 1697. Edmund Halley, best known for his comet, recorded a barrage of huge hailstones on May 10 while he was in charge of the national mint at Chester Castle. The storm smashed roofs and windows in a trail of destruction stretching 85km (53 miles) across North Wales and northwest England.

On May 15 a hailstorm struck of even greater ferocity. A track from Hitchin to Great Offley, Hertfordshire, roughly 5km (3 miles) long, was hardest hit. Hailstones described as big as a man's hand, reaching some 5.6in (140mm) across, crashed down. Crops were pulverised, the ground ploughed up and great oak trees split apart. Many people were injured and one person was reported killed, although it is difficult to believe that many more did not die under such an onslaught.

The rest of the year's weather remained wretched. Another violent hailstorm struck Herefordshire on June 17, and the summer was thoroughly sodden. Severe frosts and snow-falls began early in November, followed by a savage winter. In fact, the 1690s were blighted by bad weather, possibly caused by a veil of dust blocking out sunlight after huge volcanic eruptions in Iceland and Indonesia.

From: http://www.timesonline.co.uk/tol/news/weat...icle1790281.ece

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From The Times

May 16, 2007

Habit blows hot and cold over temperature scales

Paul Simons: Weather Eye

Whether the UK should abandon imperial measurements raises questions about temperature scales. James Shuttleworth, of Evesham, Worcestershire, argues: “Fahrenheit is a more accurate measure, there being 180 divisions between freezing and boiling, compared with 100 on the centigrade (Celsius) scale†(letter, May 12).

Accuracy is not a problem, though, because each celsius division easily divides into decimal points. The real problem is the way that Daniel Gabriel Fahrenheit invented his scale, in the early 1700s. He measured the temperature of a healthy man – women were ruled out because they were thought to have a lower body temperature. From this he set a fixed top reading of 90 degrees. He set a bottom reading of 0 degrees from a mixture of ice, water and salt; icy water on its own was set at 32 degrees.

Eventually, the scale was recalibrated using 212 degrees, the temperature at which water boils, as the upper fixed point. That gave 180 degrees between the boiling and freezing points of water, but body temperature became 98.6 rather than 96.

In 1742 Anders Celsius used a scale of 100 degrees between the freezing and boiling points of water. The simplicity of the new scale won over many countries, but the British remained wedded to fahrenheit.

Some quick conversions between the two scales are: 10C = 50F, 15C = 59F and 20C = 68F.

From: http://www.timesonline.co.uk/tol/news/weat...icle1795948.ece

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From The Times

May 17, 2007

High pressure battles to shine on first Test match

Paul Simons

The first Test match of the summer begins today, at Lord's, as England take on the West Indies. After days of downpours, the dreaded phrase "rain stops play" may be avoided to begin with, but the threat of showers will hang over the ground for the next few days. Wet and windy depressions continue to roll in from the Atlantic, and even without rain, the cloud cover will be thick enough to make for some gloomy light conditions.

Today will also be humid, which is supposed to help swing bowlers, although the reason for this is a bit of a mystery because there is no scientific proof that high levels of humidity have much effect on the spin of a ball.

However, a change in the weather may be on the way. High pressure from the subtropical Azores is battling to assert itself over the southern UK and should help to bring sunshine as well as lift temperatures. Computer forecast models suggest that the high pressure will be better established by the middle of next week, although too late for the Test match.

In fact, Lord's cricket ground does not have a particularly good record for weather. Since 1880 it has lost 19 entire days of Test match cricket through washouts, compared with 14 days at the Oval, 12 at Headingley, ten at Trent Bridge and a mere three at Edgbaston.

From: http://www.timesonline.co.uk/tol/news/weat...icle1801177.ece

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From The Times

May 18, 2007

Alexander's greatness was helped by rising seas

Paul Simons

Rising sea levels sometimes present unusual opportunities. In 332BC Alexander the Great made a stunning conquest of the Phoenician city of Tyre, after overrunning all the other cities along the coast of what is now Lebanon. At that time Tyre was an island about 1km (0.6 miles) off the coast, and the sea made a formidable defence. But after laying siege for several months, the army built a causeway through the sea, a phenomenal engineering feat. Alexander then marched on the city and seized it.

A new study reveals the secret of the causeway's construction. Tyre had become an island 8,000 years ago after the last ice age, when sea levels rose rapidly. By 6,000 years ago, the island sank further under rising waters, but the newly sunken land blocked waves from reaching the coast, and sediment built up on the seabed. More silt was added from deforestation and farming on the mainland, washed into the sea by greater rainfall. This created a narrow sandbar between the coast and island, about 1-2 metres (3-6½ft) under water.

Alexander's engineers piled up timber, stone, and rubble onto the sandbar to build a causeway to the island before the army marched on it. After Alexander's victory, the causeway altered the sea currents around the island; more silt built up a land bridge until it became a broad peninsula.

From: http://www.timesonline.co.uk/tol/news/weat...icle1805602.ece

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From The Times

May 19, 2007

Waves of destruction may have no apparent cause

Giant waves lashed the tiny island of La Réunion, near Mauritius, without warning last Saturday night. Waves towering 11m (36ft) high smashed into the port of Saint Pierre, destroying wharfs, bursting into buildings and leaving two fishermen dead when their boat capsized.

La Réunion is no stranger to storms – during a cyclone in February it broke a world record for the greatest rainfall over 24 hours. But in the recent incident there was no storm to be seen, nor a tsunami. However, satellites revealed a severe storm off the coast of South Africa, nearly 4,000km (2,500 miles) away, which set off a huge sea swell. As the waves drew near to Réunion, they slowed and rose into huge peaks.

Britain has also been struck by monstrous ocean swells. On February 13, 1979, the English Channel was calm when, without warning, massive waves hit the Dorset coast. The waves broke over Chesil Beach and sea wall, devastating the area of Chiswell, Portland. "A wave came over the beach, picked up our car and smashed it down the road," said Jennie Wellman to the Dorset Evening Echo. "It smashed in our bay window and our front door." Cars, boats and pebbles were piled up against buildings, and 30 houses were destroyed.

The waves had been generated by a storm near Canada three days earlier.

From: http://www.timesonline.co.uk/tol/news/weat...icle1811151.ece

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From The Times

May 21, 2007

Prepare for the blistering summer of 2003, part two

Paul Simons

Can the weather repeat itself? Take this description of 2003: a relatively mild winter was followed by a warm, dry and sunny spring. An especially long drought through March and April was broken in late April; May was changeable, with a warm beginning and a cool, cloudy and very wet middle.

This almost describes the weather this year, and if the weather does repeat itself what will the rest of the year bring?

The weather improved in late May 2003 – and computer forecast models suggest something similar will happen this week. Those rising temperatures four years ago heralded a blistering hot summer, interspersed with some unsettled bouts and heavy showers. But most of all the summer of 2003 will be remembered for the astonishingly hot August.

It began with a strong anticyclone that steadily stoked up temperatures, and on August 9 a new Scottish record of 32.9C (91.2F) was recorded at Greycrook in the Borders. But the next day was even more extraordinary, when a new UK record temperature of 38.5C (101.3F) was logged at Brogdale, near Faversham, Kent, the first time the 100F mark was passed in this country.

The rest of 2003 continued to be fairly dry, warm and sunny. There is no guarantee that 2007 will follow the same pattern, but watch out for a steady build-up of high pressure and temperatures this summer.

From: http://www.timesonline.co.uk/tol/news/weat...icle1816548.ece

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From The Times

May 22, 2007

Growers ban buds from blooming before Chelsea

Paul Simons: Weather Eye

Growers at the Chelsea Flower Show this week have had a tough time. The warmest April on record set off a premature burst in plant growth, with flowers blooming around a month in advance of normal. Some nurseries resorted to putting their plants into darkness, using refrigeration units to cool them, or even putting straitjackets around individual flower buds to prevent them opening.

That phenomenal warmth last month was not unique to this country. Iceland broke its April temperature record with 23C (73F), when 5C (41F) is the norm. Even more surprising, it happened in the north of the country, just outside the Arctic Circle.

Across the globe, land surface temperatures in April were the warmest on record. The greatest hotspots were Europe, Russia and Alaska. The period January to April was also the warmest on record across the world. Snow cover last winter was way below average across the northern hemisphere, and the Arctic Ocean had its smallest cover of ice since measurements began in 1979.

For the UK, this May is also warmer than normal and indications are that this will continue. All together, it fits the pattern of growing climate change.

From: http://www.timesonline.co.uk/tol/news/weat...icle1821354.ece

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From The Times

May 23, 2007

Bad outlook when the sun hits dirty windows

Paul Simons: Weather Eye

Dirty windows are more than an eyesore – they may also worsen smog pollution. Scientists have found that the grime that builds up on glass is not just unsightly, it also contains nitrates and nitric acid left over from traffic pollution. If these nitrogen compounds settle on plants or soils they disappear as they are absorbed, or eaten by microbes. But on windows, they get trapped in grime.

When the sun shines on the mucky glass, the nitrogen compounds can be recycled back into nitric oxides and waft back into the air. Those nitric oxides then can be converted by sunshine into ozone, the choking pollutant that can cause smog on sunny days in calm weather.

The new study, published in the journal Environmental Science & Technology, suggests that two thirds of the nitrogen compounds landing on windows are recycled into nitric oxides. The dirty-window problem, as well as grime built up on buildings, roads and other hard man-made surfaces, could account for an unknown source of nitrogen involved in smog pollution, which has been puzzling scientists.

Perhaps the discovery could spur the use of a self-cleaning glass invented by Pilkington, the glass manufacturer.

The surface is coated with an extremely thin film of titanium oxide, a chemical used in food-stuffs, toothpastes and sun cream. In sunshine, the titanium oxide absorbs ultraviolet light and destroys dirt on the glass.

From: http://www.timesonline.co.uk/tol/news/weat...icle1826596.ece

From The Times

May 24, 2007

Summer's dry heat gives English wines a sparkle

Paul Simons

English wine is no longer a joke. This week English vineyards collected a record haul of medals at the world's biggest blind-tasting wine competition, the International Wine Challenge, winning 21 medals, compared with 16 in 2006 and ten in 2005. Sparkling wines are doing particularly well, and especially in Surrey, Sussex and Kent, which share almost identical weather and soils to the Champagne region in northeastern France.

Climate was always seen as the Achilles' heel of English vinegrowing, and it not just a question of good summer weather. A late frost in April can hit the vine flower buds as they burst open, killing the buds and slashing yields. In May and June, heavy rainfall makes for poor pollination of the flowers, with less fruit set. The summer needs lots of hot sunshine to swell the grapes, with as little humidity as possible to avoid mildew and fruit-flies. And September and October need to be hot for the grapes to turn sweeter, and dry conditions to avoid fungal infections. In fact, a good autumn is so important it can help to make up for a poor summer.

The list of weather demands is such a tall order it might seem absurd to contemplate commercial vineyards in our climate. But over the past few years vinegrowing has thrived, and vintage years such as 2003 are paving the way for a burgeoning industry.

From: http://www.timesonline.co.uk/tol/news/weat...icle1832278.ece

From Times Online

May 25, 2007

Lightning in Ethiopia is the real hurricane trigger

Paul Simons

The hurricane season begins on June 1, and the storms will be tracked as they head out as small depressions on the other side of the Atlantic, off western Africa. But for an even earlier warning sign of trouble, forecasters might need to keep an eye on lightning in Ethiopia.

According to new research, the highlands of Ethiopia are the real birthplace of hurricanes, as intense thunderstorms kick-start them into life. The thunderstorms block the path of trade winds and, rather like boulders in a stream, send the winds spinning off into turbulent eddies. Scientists monitored bouts of intense lightning from the region and found the bigger the storms, the larger the turbulence they set off.

This disturbed atmosphere creates blocks of low pressure, and about half of these go on to spawn storms off the West African coast before they head out across the Atlantic. Whether these depressions develop into hurricanes depends on many other factors, such as a warm sea, calm winds higher up in the atmosphere, and a lack of dust blown off the Sahara.

Despite the vast distances between Ethiopia and the hurricane belt of the US and Caribbean, the link between the thunderstorms and hurricanes is remarkably strong. In the past two years, about 85 per cent of intense hurricanes, including Hurricane Katrina, can be traced back to big thunderstorms in eastern Africa.

From: http://www.timesonline.co.uk/tol/news/weat...icle1837764.ece

From The Times

May 26, 2007

Dunkirk evacuation had high-pressure assistance

Paul Simons: Weather Eye

On this day in 1940, the evacuation of Allied forces began from Dunkirk. The British, French and other troops had been pushed back into a small pocket around Dunkirk by the rapid German advance through northern France. At first the Royal Navy thought that few of the troops could be evacuated under a hail of artillery, bombs, gunfire and U-boat attack. The situation seemed an unmitigated disaster, but the weather came to the rescue.

For days on end, the air over the English Channel was calm and the seas flat as a mirror as high pressure dominated, and a gentle southerly breeze blew under largely clear skies.

These tranquil conditions allowed the Royal Navy and a flotilla of hundreds of small boats to reach the stranded troops, even in the shallow waters along the beaches of Dunkirk. Although the evacuation was attacked repeatedly from the air, there was some protection at times from shrouds of fog, which developed in the calm air. A weak front brought thundery showers and a brief burst of wind overnight on May 30, but otherwise conditions remained calm into June.

By the end of the evacuation on June 4, 338,000 men had been rescued. But to show just how wild the Channel can be at this time of year, in June 1944 the D-Day invasion was almost scuppered by weeks of gales and high seas.

From: http://www.timesonline.co.uk/tol/news/weat...icle1842593.ece

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From The Times

May 28, 2007

Bank Holiday weekends marked by hailstorms

Weather Eye: Paul Simons

If today's weather seems like another example of a diabolical Bank Holiday, take some comfort that worse has happened in the past.

This year marks the 40th anniversary of the Spring Bank Holiday, after it was divorced from the Whitsun holiday. In 2000 unrelenting rain in southern England reached up to 100mm (4in) and set off flooding in parts of East Anglia and the South East. In 1984 it rained almost the whole Bank Holiday weekend, and was also bitterly cold. A year later giant hailstones smashed greenhouses and crops in northwest Essex.

But the old Whitsun Bank Holidays could be even worse. On Whit Monday, 1944, a terrific cloudburst in Yorkshire set off a flashflood in Holmfirth valley that destroyed bridges, houses and factories, and killed three people.

Most dreadful of all was Whitsun in May 1891, when snow fell thick over Britain as far south as Bath and the Home Counties, and lay some 150mm (6in) deep around Norwich. Heavy, destructive hailstorms also broke out in many areas. "So raw and cold was the air over eastern and southern counties that it did not rise once above 42deg [6C] whether in London or Yarmouth," reported The Times. "There was a constant succession of snow and hailstones." Many places were also struck by severe frost that devastated orchards and many ground crops.

From: http://www.timesonline.co.uk/tol/news/weat...icle1848347.ece

From The Times

May 29, 2007

Conditions even worse than a May Bank Holiday

Paul Simons: Weather Eye

The Clovis people, one of the earliest known cultures in North America, flourished as the last Ice Age ended. They hunted big animals such as mammoth, giant ground sloths, camels and sabre-toothed cat, using a distinctive fluted spear.

But 12,900 years ago the Clovis and the giant animals all vanished. Now, new evidence suggests that the reason for their mysterious disappearance came from outer space. It is thought that a comet, possibly three kilometres (1.9 miles) wide, smashed into the Earth's atmosphere, exploding into giant fireballs that set much of North America ablaze in vast wildfires. The evidence for such an apocalypse comes from a thin layer of strange debris, featuring microscopic diamond dust and the rare element iridium, found peppered across North Africa and also parts of Europe. This debris is typical of the explosion of a comet.

As the fireballs rained death and destruction on the ground, they also would have crashed into much of the vast icesheet covering the northern half of North America.

This is exactly the time when it is known that colossal melt-waters surged into the North Atlantic, throwing ocean currents off-course and plunging the world into an abrupt freeze that lasted more than 1,000 years. That freeze was a severe blow to the early Stone Age cultures emerging at the end of the last Ice Age.

From: http://www.timesonline.co.uk/tol/news/weat...icle1851898.ece

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From The Times

May 30, 2007

Jet stream delivers a cold shock with holiday's rain

Paul Simons: Weather Eye

It was a shocking May Bank Holiday, rounding off a thoroughly miserable weekend for many places. Monday's washout brought a month's worth of rainfall to the Isle of Wight. It was so cold that snow fell in the Cairngorms and Lake District, and sleet swept down on the Chilterns and surrounding areas.

High Wycombe, Buckinghamshire, was the coldest place during the day, at 4.8C (40.6F). Statisticians had a field day as they calculated that it was the coldest day for a Test match played in England, when the temperature dropped to 7.4C (45.3F) at Headingley. The previous lowest temperature for an England Test match was at 8C (46F) at Edgbaston in 1965, against New Zealand.

However, it was far from a complete disaster over the UK. Parts of South West England, Northern Ireland, Wales and Scotland enjoyed some sunshine; Tiree in the Western Isles, Scotland, had more than 14 hours of sunshine.

The cause of the spectacular weather was a vigorous depression tearing through the English Channel. This low pressure system had begun life in the Canadian Arctic a few days previously, swung past Greenland and was dragged much farther south on the jet stream, the fast ribbon of wind a few miles high. As the depression swept through southern Britain, it drew in northerly winds from the Arctic.

From: http://www.timesonline.co.uk/tol/news/weat...icle1857055.ece

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From The Times

May 31, 2007

Russians feel the heat as temperature hits new high

Tony Halpin in Moscow

Russians are wilting under record temperatures as Moscow experiences its hottest May in 128 years.

The capital set a new high for the third consecutive day yesterday as temperatures reached 31.9C (89.4F), the hottest May 30 in 116 years. On Tuesday the temperature reached 32.2C, and the previous day was warmer still, at 33.2C. The five-day spell this week was the hottest since records began in 1879.

Forecasters predict that the intense heat will continue until the weekend.

The blistering sun, combined with heavy humidity in Moscow, had tragic consequences. Rescue services reported that at least 28 people had drowned in the city's ponds and rivers this month, many of them while they were drunk. Fifty people had been rescued after getting into difficulties while swimming in the past week, compared with seven for the same period last year.

Emergency services reported a 50 per cent increase in people suffering respiratory problems as the hot weather combined with traffic fumes to make breathing difficult on Moscow's polluted streets.

Many people waded fully clothed into the capital's many fountains and ponds to cool off yesterday, even though it is illegal. Police turned a blind eye.

Electricity services struggled to cope with the demand for power as air conditioning was used in homes and offices round the clock. Dozens of people had to be rescued when 300 lifts broke down.

Sales of ice cream have soared by 60 per cent as temperatures reached 10C above the average for May. Valery Yelhov, head of the Russian ice cream manufacturers' union, said: "Ice cream makers have been unable to deliver enough. Between 150 and 200 tonnes are being sold daily in the capital."

Animals at Moscow zoo found it hard to keep cool and staff prevented the walruses from bathing in their pool because the water was too warm for them. Moscow City Council has sprayed the streets with water twice a day to try to cool the asphalt and to reduce the air temperature.

Gennady Onishchenko, Russia's top public health official, suggested that people should take it easy at work to avoid heat exhaustion.

He said: "It would be a good idea to work in an air-condi-tioned place during the peak heat hours and to take extra hours to rest."

Records also fell in many other parts of European Russia. Tatiana Pozdnyakova, a spokes-woman for the Moscow Weather Bureau, said that the heat-wave was caused by the influence of a high-pressure system over Kazakhstan. "As it revolves, it is sending hot air from Central Asia to Russia. All of European Russia is experiencing hot weather," she said. "Every other city in this region has seen new temperature records set."

The soaring temperatures follow an unseasonably warm winter in which Moscow experienced its first serious snowfall only in January.

From: http://www.timesonline.co.uk/tol/news/weat...icle1862694.ece

From The Times

May 31, 2007

Flowers give forecasters a sign of changes in the air

Weather Eye Paul Simons

Last Saturday was dull and quite warm, but there was a warning sign of a change on the way from the gazanias in my backgarden. Gazanias are daisy-like flowers that like hot, dry weather and their petals close up before rain. The flowers proved to be impressive weather forecasters – the next day it bucketed down with rain.

Many other flowers sense the approach of rain by closing up, including the wood anemone, morning glory and scarlet pimpernel, also known as the poor man's weather glass. These flowers all give a short-term weather forecast, probably sensing a rise in humidity before it rains to avoid getting their pollen wet.

In plantain flowers, the pollen bags, the anthers, squeeze shut on dewy nights or during wet weather, protecting the pollen inside. The movement can be surprisingly fast: anthers of the bastard toadflax shut up within 30 seconds of being moistened.

One flower in the Rocky Mountains of Wyoming can even forecast thunderstorms. The bell-shaped flowers of the Arctic gentian usually open upwards to the sky, but hours before a thunderstorm they squeeze shut to avoid the rain.

The gentian senses thunderstorms from changes in temperature, as the air cools beforehand. In fact, they are so sensitive that even a passing cloud is enough to chill them and start the movement.

From: http://www.timesonline.co.uk/tol/news/weat...icle1862794.ece

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From The Times

June 1, 2007

Leaking May and a warm June bring on the harvest

Paul Simons

In May 1773 George III passed the Tea Act, which incensed the American colonies by undercutting their tea prices, and helped to spur a rebellion.

That same month was also the wettest May on record in England and Wales, with an average of 152mm (6in) rainfall.

The final tally for this month of about 120mm (4.7in) looks slightly less than that, but it is still twice the month's norm, and beating the wet May last year. It will probably be among the ten wettest Mays, and possibly the wettest for 40 years. Certainly it helped to ruin both May Bank Holidays, almost wrote off the Test match at Headingley and brought the Chelsea Flower Show to a soggy end. But despite the disappointments, overall temperatures remained above average for the month – again, rather like May last year.

With Wimbledon beckoning and England looking forward to the next Test match at Old Trafford, what might the weather bring this June?

"A leaking May and a warm June, bring on the harvest very soon", goes an old Scottish saying. The Met Office is standing by its forecast of a likely warm summer, but the outlook for June is rather mixed – more rain and some warmer days, which is good for farmers, but not much sign of really hot weather. However, if 1773 is anything to go by, the summer will be a washout and remain wet well into the autumn.

From: http://www.timesonline.co.uk/tol/news/weat...icle1867881.ece

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From The Times

June 2, 2007

Fair weather hasn't always favoured Epsom Derby

Paul Simons: Weather Eye

The weather for today's Derby on the Epsom Downs looks very encouraging, but the race has sometimes been run in very challenging conditions.

In 1867 there was snow lying on the Epsom Downs before the race day dawned on May 22. As the day wore on, dark skies, biting winds, sleet and heavy snow showers swept across the course. The crowds that usually flocked to Derby Day were thin on the ground, and even the vagabonds and pickpockets were absent. Ten false starts delayed the race for nearly an hour, but the racegoers were eventually rewarded with an astonishing race when Hermit, a 1,000-to15 outsider, and nursing a serious injury, charged through from the back to win.

Charles Dickens was a frequent visitor to the Derby, "A dull little place for fifty-one weeks in the year, with a sharp fever-fit in the 'Derby week' ", he wrote of Epsom. In 1863, he described a big downpour that left the racecourse sodden and the railway station "an oasis of boards in a sea of mud", adding that "whilst last year it was iced champagne, claret cup and silk overcoats, now it ought to be hot brandy and water, foot baths and flannels".

The Downs are also highly exposed to thunderstorms. Two spectators were killed by lightning in 1904, and several people killed by lightning and floods in 1911 as crowds left the racecourse.

From: http://www.timesonline.co.uk/tol/news/weat...icle1873235.ece

From The Times

June 4, 2007

East Coast US braced for Katrina-style hurricanes

Paul Simons: Weather Eye

If you are planning a holiday to the Caribbean, Gulf or East Coasts of the US in the next few months, it might be wise to keep an eye on the weather forecasts. The hurricane season officially began on Thursday, and predictions are for an upsurge in storm activity after last year's quiet season. The US National Oceanic and Atmospheric Administration is expecting up to 17 tropical storms, with up to 10 developing into hurricanes, five of which could be as intense as Hurricane Katrina in 2005, or worse.

It is not possible to say where these storms will strike. But with so many storms forecast, previous seasons' patterns suggest that between two and four of them will make landfall on the East and Gulf coasts of the US. And it only needs one major hurricane to make landfall to become a disaster.

However, experts are divided over why the number of hurricanes is likely to increase. Some blame climate change – the surface of the Atlantic tropical seas is growing much warmer than normal, providing a rich source of heat and humidity, essential to help to grow and develop tropical storms.

But others argue that the Atlantic naturally goes through long cycles of hurricane activity stretching over decades. In one recent study, the upsurge in hurricanes in recent years is taken as a return to "normal conditions" after an unusually quiet period.

From: http://www.timesonline.co.uk/tol/news/weat...icle1878526.ece

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From The Times

June 5, 2007

Greenland's bonanza is a disaster for the rest of us

Paul Simons: Weather Eye

Ice covers most of Greenland, but the world's largest island is also rich in minerals. West Greenland has some of the oldest rocks on Earth, including kimberlites, the diamond-bear-ing rocks famous in South Africa. For the past decade, many companies have been scouring the area and several hundred diamonds have been found, although as yet no diamond mine has been opened. But in 2004 a gold mine was opened in southwest Greenland, and a zinc and lead mine reopened this year.

The mineral wealth of Greenland is revealed as its huge ice cap retreats under the onslaught of rising temperatures. Already, the map of Greenland's coastline is changing as new islands called nunataks, meaning "lonely mountains" in Inuit, emerge from beneath the melting ice.

The changes in Greenland's ice have caught many scientists by surprise. Its massive glaciers are sliding towards the sea ever faster, and twice as much ice is being dumped into the sea as five years ago. That is exposing more rock for prospecting, and as the sea ice disappears around the coasts the shipping season to export minerals is growing longer. But the bonanza for Greenland is a disaster elsewhere. The Greenland ice sheet covers an area about the size of Mexico and is up to 3km (2 miles) thick. If that all melted, the world's seas would rise 7m (23ft).

From: http://www.timesonline.co.uk/tol/news/weat...icle1884282.ece

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From The Times

June 6, 2007

Millions brave the rain for a glimpse of the Queen

Paul Simons: Weather Eye

Thirty years ago today, the country was celebrating the Queen's Silver Jubilee, but the weather was a big let-down. Over the preceding weekend a vicious depression swept in from Iceland and blew in wind and rain. The weather went downhill as rain spread southwards, temperatures tumbled and snow fell over the Scottish mountains. In some parts it was the first rain for more than two weeks.

The usual late spring Bank Holiday at the end of May had been changed to a special Bank Holiday for Monday, June 6. If it had been held on the late May date the weather would have been fine.

Instead, conditions grew atrocious. It was the windiest day of the entire summer, lifeboats were called out in various coastal locations to rescue boats in trouble, and many parts of the North had their wettest and coldest day of the month – the maximum temperature in Glasgow reached only 7C (45F).

On the evening of June 6 the Queen lit a bonfire beacon at Windsor to begin a chain of beacons across the sodden and chilly country. And despite continuing rain, thousands of people camped out overnight in London streets to get a good view the following day of a royal procession to St Paul's for a service of thanksgiving. In fact, a crowd of more than a million braved the weather to watch the spectacle.

From: http://www.timesonline.co.uk/tol/news/weat...icle1890261.ece

From The Times

June 7, 2007

Summer fog foils Scottish invasion of England

Paul Simons: Weather Eye

June is turning out largely sunny, warm and dry, but not everywhere.

Many western areas have woken up to morning sunshine while eastern regions may be wondering where the summer has gone – skies have been leaden grey with low cloud this week, and fog enveloped parts of the East Coast on Monday.

This was a typical early summer fog, called haar in Scotland or fret in England. Although the land in early summer is steadily warming up, the seas around Britain are still cold. Warm, moist air wafting across from Northern Europe cools down over the chilly waters of the North Sea and condenses into fog or low cloud. During the night, when the land is cool, that fog or cloud can penetrate far inland, which makes a gloomy start to the day. But as the land warms up during the day, the clouds break up and sunshine breaks through.

It was a haar that foiled a Scottish invasion of England in 1174 when William the Lion, King of Scotland, captured part of Northumbria. His army camped at Alnwick, near the coast, but under cover of thick morning haar, an English force launched a surprise attack on the Scots and captured William. The Scottish King was taken to Falaise in Normandy and surrendered the independence of his country, which, in effect, became a fief of England for 15 years.

From: http://www.timesonline.co.uk/tol/news/weat...icle1896065.ece

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From The Times

June 8, 2007

Cyclone turns the streets of Muscat into rivers

Paul Simons: Weather Eye

A cyclone has struck in an unexpected part of the world.

Cyclone Gonu battered Oman in the Arabian Peninsula on Wednesday with sustained winds reaching about 130km/h (80mph), the equivalent of a Category 1 hurricane. It also unleashed rainfalls of about 100mm (4in), compared with a norm of 3mm (0.1mm) for the whole of June.

Streets in the capital, Muscat, turned into rivers, and at least 12 people were killed. The desert, too, was awash with water, and flashfloods were triggered as rainwaters cascaded down mountains and surged through wadis that cut through the desert.

Gonu crossed the Gulf of Oman yesterday and hit the southeast coast of Iran, although the storm had grown much weaker by then. However, at sea the storm had previously reached supercyclone status, the highest category of storm strength, peaking at wind speeds of about 240km/h (150mph), which whipped up 12-metre (40ft) waves.

Records in this region go back only to 1945, but cyclones are very unusual and such a severe storm is unheard of.

So was this storm simply a one-off freak or part of a more worrying trend? Over the past few years several other cyclones have struck in unexpected places around the world. Scientists are still deciphering what significance, if any, these phenomena hold.

From: http://www.timesonline.co.uk/tol/news/weat...icle1901227.ece

From The Times

June 9, 2007

Full moon's light has a warming effect on Earth

Paul Simons: Weather Eye

Sussex Police are to deploy more officers when there is a full moon after a study of crime figures that linked violent behaviour to the phases of the Moon (The Times, June 6).

This is a controversial area, though – and so, too, is the idea that the Moon can affect the weather. However, a study in the US has revealed an unexpected 18-year pattern of rainfall in the Midwest. This matched a lunar cycle as the Moon orbits the Earth, and seemed to affect winds sweeping down from the Rocky Mountains, which helped to create drought or rain.

Elsewhere, the full moon has been linked to slightly fewer bouts of heavy rainfall in Sydney, and also during the monsoons in Jakarta and in Mangalore on the west coast of India.

There also appears to be a link between the Moon and the daily range of temperature. A survey of weather records has revealed that the daily range rises slightly towards full moon, and falls to its lowest at new moon, a difference of up to 0.3C (0.5F).

One explanation is that moonlight can warm the Earth slightly at full moon, although only at night, of course. But the position of the Earth and Moon in the solar system is also important. At full moon, the Earth moves slightly closer to the Sun than at new moon, receiving a touch more solar radiation during the day and raising maximum temperatures.

From: http://www.timesonline.co.uk/tol/news/weat...icle1907025.ece

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From The Times

June 11, 2007

No more mercury rising in our barometers

Paul Simons: Weather Eye

The European Union is to ban the use of mercury in barometers ("Mercury barometers on way out ", June 6). This brings to a close a tradition that began on this day in 1644, when Italian mathematician and physicist Evangelista Torricelli described in a letter what we now call a barometer.

He set out to answer a fundamental question at that time: "Does the air have weight?" He used a long glass tube with a closed end, filled it with mercury, and turned it upside down in a basin filled with mercury.

Instead of rushing out into the basin, the mercury came to rest part of the way up the tube. Torricelli realised that the mercury was forced up the tube by the pressure of air pushing down on the mercury in the basin.

And he made another key insight – over the days, he saw that the level of mercury fluctuated slightly as the air pressure changed.

In fact, we live at the bottom of a great ocean of air above us, a weight constantly pressing down on our heads. Evolution has taken care that we do not notice this pressure, except when a sudden change in air pressure makes our ears pop, for instance on a plane taking off.

But changes in that air pressure have huge effects on our weather – which is why the barometer is still a key weather instrument.

From: http://www.timesonline.co.uk/tol/news/weat...icle1913057.ece

From The Times

June 12, 2007

Austen's pithy comments on the British weather

Paul Simons: Weather Eye

Jane Austen's humour was subtle (letters, June 11 ), and also used meteorology to good effect. In Sense and Sensibility the Dashwood sisters visit the Palmers at Barton Park. However, the irascible Mr Palmer is in a belligerent mood: "How horrid all this is!" said he. "Such weather makes everything and everybody disgusting. Dullness is as much produced within doors as without, by rain." But rain proves crucial, when Marianne Dashwood ventures outside for a walk. "Suddenly the clouds united over their heads, and a driving rain set full in their face." Marianne falls and sprains her ankle and is rescued by the dastardly Mr Willoughby, with near-disastrous consequences.

In letters to her sister, Cassandra, Jane Austen makes some pithy weather observations. "What fine weather this is!", she wrote in November 1798. "Very pleasant out of doors at noon, and very wholesome – at least everybody fancies so, and imagination is everything." And in December 1815 she enthused about unseasonally mild weather: "I enjoy it all over me, from top to toe, from right to left, longitudinally, perpendicularly, diagonally."

Perhaps she was influenced by Luke Howard, the pioneering meteorologist. He passed by her home in Chawton, Hampshire, in July 1813, and although we do not know if they met, her letters and novels became full of weather after this time.

From: http://www.timesonline.co.uk/tol/news/weat...icle1917792.ece

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From The Times

June 13, 2007

There's plenty of snow in June – up in the clouds

Paul Simons: Weather Eye

It may well snow today over Britain. But before you reach for an overcoat, gloves and shovel, this is perfectly normal, because the snow will have melted into rain long before it hits the ground.

Much of our rain starts off as snow high up in the cold air of clouds before melting in warmer air below. This was discovered in 1933 by the Swedish meteorologist Tor Bergeron while walking on cloudy mountains. He realised that the clouds contained tiny water droplets and ice crystals. The water droplets actually cooled well below freezing point but without freezing, what is called supercooled water. The ice crystals grew larger at the expense of the water droplets, until they clumped together into snowflakes. These eventually grew heavy enough to fall through the clouds before melting in warmer air.

So most of our rain is actually melted snow and is typical of temperate and polar regions. Only if the air is cold below do the snowflakes survive and reach the ground as snow. However, about a third of the world's rainfall is "warm rain", typical of the tropics, in which water droplets grow into raindrops without turning to snow.

Bergeron also came up with the weather front symbols on weather maps – triangles for cold fronts, bumps for warm fronts, and both symbols for occluded fronts. Today is the 30th anniversary of his death.

From: http://www.timesonline.co.uk/tol/news/weat...icle1923595.ece

From The Times

June 14, 2007

Sun burns brightest using magnetic waves of sound

Paul Simons: Weather Eye

The hottest part of the Sun is fuelled by gigantic sound waves. During a solar eclipse, the main body of the Sun is blotted out by the Moon's shadow and a ruby-red ring of "fire", normally hidden from view, appears around it instead. This is the Sun's chromosphere, and is largely responsible for the ultraviolet radiation that bathes the Earth.

Strangely, it is also the hottest part of the Sun, soaring to about 11,000C (20,000F), compared with the Sun's visible surface of about 5,500C (10,000F).

The mystery of why the chromosphere is so hot has baffled scientists for decades, but a recent study has tracked it down to sound and magnetism.

The Sun's interior is flooded with very low-frequency sound waves packed with energy, more like seismic waves from an earthquake than ordinary sound we can hear. As the Sun's magnetic field breaks out into fountains on its surface, it allows the energetic sound waves to burst out from the interior into the chromosphere.

"The Sun's interior vibrates with the peal of millions of bells," explained Scott McIntosh, of the Southwest Research Institute in Boulder, Colorado. "We've been able to show how the sound escapes and travels a long way using the magnetic field as a guide." The leaking sound waves are revealed as jets of hot gas extending thousands of kilometres above the Sun's surface.

From: http://www.timesonline.co.uk/tol/news/weat...icle1929305.ece

From The Times

June 15, 2007

Rocket lightning gives Nasa a high-speed sprite

Paul Simons: Weather Eye

For more than a century, people occasionally reported seeing what looked like sudden firework displays over the tops of thunderclouds. These were sometimes called rocket lightning, although few scientists gave much thought to them. But in 1989 Nasa recorded two giant pillars of light flashing above a distant storm, using a low-light television camera.

This was called a sprite and further investigations revealed something that looked like a red jellyfish with blue tendrils dangling down. Sprites soar up to 95km (60 miles) high into the mesosphere, the layer of atmosphere above the stratosphere, but last no more than a few thousandths of a second.

Recently, a study using a high-speed video camera revealed that sprites form as balls of light and shoot through the upper atmosphere at one tenth the speed of light.

There are other bizarre displays over the tops of intense thunderclouds. Many appear a split second after a powerful lightning bolt has struck down to the Earth's surface. This creates a large voltage difference between the thundercloud and the upper atmosphere. Pulses of energy are thought to shoot upwards, smash into gases in the upper atmosphere and excite them rather like a multicoloured neon light.

From: http://www.timesonline.co.uk/tol/news/weat...icle1934897.ece

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From The Times

June 16, 2007

European monsoon rolls out from wet westerlies

Paul Simons: Weather Eye

What happened to summer? Much of the UK has been swimming in rains of monsoon proportions, and the downpours look set to continue next week.

In fact, this is to be expected – we are now in the European monsoon, when seasonal rains arrive on the back of wet, westerly winds rolling off the Atlantic.

Quite what drives this weather pattern at this time of year is far from clear, but the monsoon usually comes in two bursts, at the beginning and middle of June. However, the early part of this June remained dry, and only now are we feeling the full force of the wet westerlies.

The rains yesterday mostly came from a depression pumped up with warm, humid air clashing with much colder air from the north. Weather fronts draped across much of the UK had plenty of time to drop huge amounts of rain as the whole system moved around sluggishly. And more rain fell when winds flowing from the north and south converged over North Wales, the West Midlands and northwest England, sending up even more rainclouds.

The rains are expected to ease off this weekend, but a depression is heading our way next week. Beyond that, the outlook for Wimbledon and the Glastonbury Festival looks uncertain. But average temperatures this month are above normal, especially in the South.

From: http://www.timesonline.co.uk/tol/news/weat...icle1940410.ece

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From The Times

June 18, 2007

From the swamps to the wheat belt, the US is dry

Paul Simons: Weather Eye

The price of bread is rising, driven partly by drought across many of the world's granaries. In the US, more than a third of the country is suffering from a lack of rain, and the drought area is spreading.

Unusually, a great swath of the South East is incredibly dry. In Florida, Lake Okeechobee's vast waters are so low that the lake bottom has become exposed, and part of it caught fire.

Archaeologists, though, got an unexpected bonus when they discovered boats, pottery and human remains in the dried-up lake mud, evidence of what appears to be a preColombian Indian culture.

The Jack Daniel's whiskey distillery in Lynchburg, Tennessee, may suspend production as the spring water the plant depends on is drying up. The level of Lake Superior has hit its lowest level in recorded history, causing problems for shipping. Farmers in the Midwest are nervously eyeing young maize crops wilting in the dry heat.

Many western states are now in their sixth year of drought. So far, this is the driest year in Los Angeles since records began in 1877, and a poor snowfall this winter in the Sierra Nevada mountains has left a shortfall of meltwaters for rivers feeding big urban areas.

This could all be a natural fluctuation in climate, but some scientists fear it is a sign of climate change and worse droughts in the future.

From: http://www.timesonline.co.uk/tol/news/weat...icle1945923.ece