Weather Eye

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September 4, 2006 By Paul Simons

VIC TANDY, a university lecturer, was working in his laboratory at Coventry University when he broke into a cold sweat. He saw a grey form approaching, a ghostly figure with legs, arms and a foggy blur for a head. He recalled: “I felt the hairs rise on the back of my neck. It seemed to be between me and the door.” But the “ghost” vanished without a trace.

Investigations revealed that the vision seemed to be generated by an extractor fan, which gave off very low frequency sound known as infrasound, beyond the range of human hearing. When the fan was switched off, the creepy feelings and visions disappeared.

Infrasound carries over long distances, and all that we can hear is sometimes a deep rumbling sound. Infrasound can be created when strong gusts of wind clash with chimneys, and the deep vibrations can penetrate even very thick walls. Dr Tandy believed that this very low frequency sound could produce hallucinations that may account for sightings of ghosts. But infrasound could be useful for weather forecasters. The up-and-down movements of ocean waves and swirling winds of tornados and hurricanes all emit infrasound signals. In the US networks of infrasound detectors are being developed to warn of approaching tornados, often difficult to forecast any other way.

From TIMES ONLINE

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September 5, 2006 By Paul Simons

THE weather across much of southern and central Britain was quite extraordinary at the weekend. Winds gusting to 58km/h (36mph) were blowing branches and leaves off trees, and yet it was warm and humid enough to feel like summer, even in the middle of the night. There also seemed to be a smell of the sea in the air.

The strong southwesterly wind came from a sharp pressure gradient: low pressure over the north and west Atlantic contrasted with high pressure centred over Europe and eastern Atlantic. The boundary between these pressure systems looked like a diagonal slash of long isobars across the Atlantic and UK. The elongated isobars also told the story of where the warmth and maritime smell came from: they stretched deep down to the tropical mid-Atlantic, along which swept a mass of warm, humid air.

On Sunday, temperatures reached 27C (81F) at Heathrow respectable for summer, let alone early September. The pressure gradient and its wind have gone. Now high pressure is building up, bringing more settled conditions, and warm temperatures, to the southern half of the UK. Eventually the anti-cyclone will cover the country, but it is uncertain how long it will dominate as low pressure battles to exert its influence. For the time being, though, there is a welcome respite after the wet and windy weather of August.

From TIMES ONLINE

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September 6, 2006 By Paul Simons

OVER THE next few days the tides will be unusually high, which raises the threat of floods along many parts of the coast. However, if the weather stays reasonably calm there is little risk of floods and the tides will go largely unnoticed.

The high tides will come from a combination of perigee, when the Moon reaches its closest distance to Earth, and spring tide, when the Earth, Moon and Sun are in line with each other — the word “spring” is not the season but means “rise up”. Another factor is the approaching autumn equinox, when the Sun is directly over the Equator. The combination of all these comes round about every 4.5 years, but the last time it happened there was no flooding.

A much rarer event is that the Moon has reached the extreme of an 18.6-year cycle as its orbit around the Earth slowly changes. But this adds only about 2cm (0.8in) to the tides, about the thickness of a finger, so is fairly insignificant.

The clash of all the tides could be devastating only if a severe storm whips up big waves and its low pressure draws the sea up higher. A resulting storm surge could overwhelm sea defences along much of the low-lying coastline. However, with high pressure largely in control this week, sea conditions should be fairly calm. High tides will arise again in October.

From TIMES ONLINE

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September 7, 2006 By Paul Simons

A TINY change in average temperatures can make a big difference. Average temperatures in central England “crashed” from 19.7C (67.5F) in July to 16.1C (61.0F) in August, and the difference was dramatic: stifling heat gave way to a mild, typically British summer. But a reader wrote that this change of a mere 3.6C (6.5F) does not sound much of a shock, and posed the question: could this be the curse of the average (letter, September 6)?

There is a big problem with the perception of average temperatures, and a good illustration is climate change. Average global temperatures rose 0.6C in the 20th century, but such a tiny rise hardly sounds worth worrying about. So why has this tiny increase in temperature triggered such concern about the world overheating and causing a global catastrophe?

Small changes in average world temperatures have huge impacts. The depths of the last Ice Age were only about 5C colder, on average, than today. Ice Age Britain looked like Greenland, most of it crushed under a huge icesheet.

Now the climate pendulum is swinging too far the other way. Experts predict that average global temperature will rise this century between about 1.5C and 5.5C. This is a massive increase over a short space of time, and will have huge impacts around the world.

From TIMES ONLINE

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September 8, 2006 By Paul Simons

AT AROUND 5.30am on August 10, a meteorologist in Green Bay, Wisconsin, was alarmed by an image on his radar screen. A bright doughnut-shaped ring appeared suddenly, expanded rapidly and dispersed over the bay. Further investigation revealed it was a huge flock of birds leaving their roost in search of food — the image can be seen at www.crh.noaa.gov/grb/?n=060810.

Radar was first developed in the First World War when distant thunderstorms were picked up by radio interference, and used for warning pilots. This led to radar tracking of aircraft in the 1930s. But as scientists started to use smaller antennas to generate smaller wavelengths they could distinguish objects such as raindrops and hailstones.

However, weather radar also picks up birds, bats and even insects. On June 30 this year a big “cloud” appeared on radar across Wisconsin, Iowa and Minnesota. It was a swarm of mayflies that had flown up to mate before they laid their eggs and died.

Using radar for tracking wildlife could save lives. Nasa is extremely concerned with bird strikes — during the July 2005 launch of Discovery, a vulture hit the shuttle’s external tank just after liftoff, nearly causing catastrophic damage. Specially designed radar is being used now to track the birds and if necessary delay launches.

From TIMES ONLINE

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September 9, 2006 By Paul Simons

ONE of Britain’s greatest natural phenomena could be on display this weekend. Tidal bores are due to surge up certain rivers, thanks to exceptionally high tides.

The Severn Bore is the most dramatic, best seen between Minsterworth and Lower Parting, Gloucestershire, on the River Severn. Slightly smaller are the Trent Aegir in the lower reaches of the River Trent between Derrythorpe and Gainsborough, Lincolnshire, and the Dee Bore, between the Dee Estuary and Chester.

In all these cases, the high tides are forecast to thrust a mass of seawater up the rivers as a wave, the bore.

The Severn Bore is the largest in the UK because the Severn estuary funnels the tide into a tight channel and has a huge tidal range. This can create a spectacular bore, reaching 2m (6.6ft) high, pushing 33.8km (21 miles) upriver at speeds of up to 21km/h (13mph). The bore can be so powerful that surfers and canoeists ride them upriver.

Bores are strongly affected by the weather, though. Heavy rains draining into the river, high atmospheric pressure and winds sweeping downriver can swamp a bore as it pushes upriver. The best conditions are low pressure and winds blowing in the same direction as the bore, such as a southwesterly on the River Severn, which helps to funnel the seawater through the river estuary and upriver.

Details of the Severn Bore are at www.severn-bore.co.uk.

From TIMES ONLINE

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September 11, 2006 By Paul Simons

WHERE have all the hurricanes gone? This year’s tropical storm season in the Atlantic has baffled the experts. After a record number of hurricanes last year, this season was forecast to be almost as busy.

But so far only five tropical storms and two hurricanes have formed, and the season ends officially on November 30. At this stage last year, there had been a record 15 tropical storms and hurricanes, seven of which were considered major storms, including Hurricane Katrina.

The hurricane-prone areas of the Caribbean and US have been saved by an unlikely hero — dry, dusty air blowing off the Sahara.

Hurricanes are fuelled by damp, warm air, which they draw off tropical seas with a voracious appetite. But the Sahara has been billowing clouds of extremely dry and dusty air across the Atlantic, helping to strangle the storms as they try to develop.

Each summer the Sahara blows air off the African coast into the Atlantic every three to five days, and this year it has been particularly active. The desert air swamped the west coast of Africa, the spawning ground for many hurricanes, and then charged across the Atlantic, killing other storms on the way. The Saharan air has even reached Miami, where it has left fine, red coatings of dust on cars. The skies there are so hazy that streetlights have switched on early in the evening.

From TIMES ONLINE

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September 12, 2006 By Paul Simons

IT SEEMS incredible that the calendar says this is September, when blazing sunshine makes it feel like the height of summer. It is not unusual to get an occasional scorching hot day in the early days of autumn, but to get two consecutive days of 28C (82F) or higher, as happened yesterday and Sunday, is quite an event, especially as we are by now approaching mid-September.

However, we have not broken temperature records yet.The hottest September 10 was 30C (86F) in 1891 and the hottest September 11 was 32.2C (90F) in 1919, the highest temperature of that year.

Perhaps even more freakish was September 1926 when a heat wave struck even later, over September 18-20, with temperatures over 29C (84F). The 19th was the most extraordinary day, with the temperature soared to 32.2C at Camden Square, London. People were reported to have collapsed and in some cases even died in the heat.

Strangely, temperatures in September have not exceeded 32C for more than 50 years; the last time was in 1949. However, the past three years had notably warm Septembers, especially in 2003 when 28.4C (83.1F) was reached on September 17.

But a heat wave now is no guarantee that it will remain warm. In 1919 temperatures crashed on September 12, and a few days later it snowed across much of England and Wales. The weather continued to be abysmal for the rest of that autumn.

From TIMES ONLINE

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September 13, 2006 By Paul Simons

THE HIGHEST temperature on Monday was remarkable for reaching 30C, the first time this has happened in September for seven years. The 30.2C (86.3F) recorded at Heathrow beats the highest temperature reached in August: 29.7C (85.5F) on August 6 at Pershore, Worcestershire. This may be the first time that September has beaten August since 1962.

The shorter hours of daylight and lower sun in the sky tend to make September cooler than August. But the seas around the UK are usually at their warmest in early September, boosting the air temperatures. And the second week of the month is often blessed with anticyclones, bringing fine, calm conditions, and bears out the saying: September blow soft till the fruit’s in the loft.

These high-pressure systems often pass across the British Isles into Europe, quickly followed by wet and windy low-pressure systems, backing up another saying: September dries up wells or breaks down bridges.

However, these depressions often sweep in southerly winds and mild air, which is the situation today. But forecasters are watching on a more aggressive depression possibly heading our way. Hurricane Florence hit Bermuda with winds more than 160km/h (100mph) and is dying out, but its remains could swing towards the UK and bring a bout of very wet and windy weather at the weekend.

From TIMES ONLINE

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September 14, 2006 By Paul Simons

MADONNA held her first concert in Russia on Tuesday. However, the concert management had been concerned by the threat of rain which, it was said, would ruin the stage at the open air stadium where Madonna was playing. According to a Russian news report, mosnews.com, the manager of Madonna’s tour said that “rain would be an unpleasant occurrence. Madonna will dance a lot during the show and the stage must be dry.”

Russia weather experts were reported to have been so concerned about this possible calamity that they used aircraft to spray the sky over the Moscow stadium with chemicals that, it was claimed, would dry out any clouds. The treatment was developed originally to keep military rallies in Red Square dry during the Soviet Union era, and which the Chinese propose using to keep the 2008 Beijing Olympics dry.

The technique relies on cloud seeding. Silver iodide powder or other moisture- absorbing substances are used to act as “seeds”, simulating the natural salt, dust and other tiny particles in the atmosphere that help water droplets to form. Spraying clouds is claimed to increase rainfall, but by using less intensive spraying can dry out clouds. However, many weather experts remain sceptical that it works.

For the record, the weather for Madonna’s concert was dry.

From TIMES ONLINE

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September 15, 2006 By Paul Simons

ON August 26, at 4am, a teenage driver reported being chased in her car by floating lights as she drove across the Orwell Bridge on the outskirts of Ipswich.

According to a report in the Evening Star, Ipswich (www.eveningstar.co.uk), two spinning lights appeared about 3.7m (12ft) above the windscreen, each about the size of an orange, and appeared to be a dull, diffuse sort of light, of no particular colour. The driver, who wished to remain unnamed, said: “They definitely seemed to be staying with the car. I’ve never been so scared.”

At about the same time that night, similar mysterious lights were seen by other eyewitnesses just over a mile (1.6km) away in Ipswich.

Maybe this was simply a beam of light being projected in the sky. But it was reminiscent of another incident near Colwyn, North Wales, in June 1981. At about 8Pm a woman drove into a bank of mist on a country road, when suddenly a glowing and spinning ball of translucent greenish light about the size of a football appeared.

It stuck tenaciously alongside the car, about 1ft from the side window, and kept pace no matter how much the woman tried to shake it off by speeding up or slowing down. Only when the mist petered out did the light shoot up and away out of sight. This incident remains unexplained.

From TIMES ONLINE

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September 16, 2006 By Paul Simons

GAMBLING on the weather is not for the faint-hearted. Deciding on whether to take an umbrella or sunglasses for a day out is hard enough, but actually betting money on the weather is very risky.

However, you can bet on the weather on some websites, such as how many hurricanes will make landfall in the US or even in a particular state such as Florida, or the strength of a particular hurricane.

Whether it is ethical to gamble on a potentially devastating hurricane is another question, although gambling used to be far more morbid — in the 1700s people bet on how many people would die from disease outbreaks in particular cities. Another word of caution on weather betting is that it is incredibly difficult to predict hurricanes. Forecasters have been wrong-footed by this year’s hurricane season, which was far quieter than predicted. A company based in Leeds has taken a different line on weather betting. The Weather Lottery costs £1 a week, and players have to guess what the last digit of the daily temperature is going to be in Corfu, Istanbul, Tenerife, Innsbruck, Stockholm and Edinburgh. Temperatures are in fahrenheit, so if you think it will be 62F in Edinburgh, you put a 2 down. The correct last digit for all six cities wins £10,000. A third of the lottery’s money goes to participating charities.

From TIMES ONLINE

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September 18, 2006 By Paul Simons

EIGHTY years ago today one of the most devastating hurricanes in US history hit Miami.

Hurricane warnings came too late to evacuate the population of Miami before a Category 4 storm struck in the early hours. A storm surge reaching up to about 4.5m (15ft) smashed into the seafront, flooding buildings and leaving streets strewn with boats and sand up to several feet high, in some places completely burying cars. Buildings collapsed, power cables fell and debris flew through the air.

Miami was then a small but booming city, and most residents had little experience of hurricanes. As the eye of the storm passed over in a 30-minute lull, crowds filled the streets thinking the hurricane had gone. But they were horribly wrong — the rear half of the hurricane burst through with winds reaching 206km/h (128mph), causing most of the storm’s casualties.

Hardly a building was left undamaged and about 50,000 people were left homeless. In today’s figures, the damage was estimated at more than $2 billion. It left 113 dead, drowned or crushed by debris; a total of 243 were killed after the storm tore through Florida and then struck Alabama. If a similar storm struck Miami today it would be a catastrophe; the devastation potentially could be worse than Hurricane Katrina.

From TIMES ONLINE

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September 19, 2006 By Paul Simons

THE weather is set to turn wild this week, particularly for western regions of the UK. A deep Atlantic depression is forecast to strike on Wednesday, and could turn even stronger by Thursday and Friday because the storm may sweep up the remains of Hurricane Gordon, the most powerful hurricane to brew up this year in the Atlantic.

Gordon attracted little attention in the news as it avoided land and caused no damage. It billowed up east of the Caribbean, tracked north way past Bermuda and then, last Wednesday, blew up in the mid-Atlantic into a Category 3 storm, the first big hurricane of the season, with winds reaching 193km/h (120mph). The storm is dying down, but is still dangerous and could threaten the Azores with a direct strike.

As Gordon tracks further north it will hit the colder waters of the Atlantic, the graveyard for mid-Atlantic hurricanes. There the storm will run out of the warm water it needs to fuel its voracious energy demands. Also, high level westerly winds will smash into the top of the storm and destroy it further. However, the huge amount of warm, humid tropical air carried by the hurricane will be dumped into the atmosphere. This is expected to become absorbed into another, fairly typical, Atlantic depression further north, and create an intense storm as it heads towards the UK.

From TIMES ONLINE

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September 20, 2006 By Paul Simons

MID-SEPTEMBER is not supposed to be like this. It feels like summer, with respectable daytime temperatures and mild nights over much of the country. More unusually, this warm spell comes after such a dismal August, with grey skies and torrential rain. So what is going on with the weather?

The first half of September was dominated by high pressure, largely centred over the UK or Europe. This tended to bring plenty of sunshine and a warm breeze blowing off the Continent. Since then, low- pressure systems have had been trying to barge into the UK, bringing more wind and cloud, especially to the West. But their progress eastwards has tended to be blocked by high pressure over Europe. In the next few days the battle between these low and high-pressure systems is set to intensify. The remains of Hurricane Gordon are expected to become absorbed into an Atlantic depression, particularly over Ireland and western Britain, with fierce winds and torrents of rain. But despite this, temperatures could remain surprisingly high. Southerly winds will sweep up mild air, and the remains of Hurricane Gordon will help to make the atmosphere thick with warm, humid air drawn up from tropical seas. The remains of another storm, Hurricane Helene, may hit the UK next week, delivering even more warm air.

From TIMES ONLINE

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September 21, 2006 By Paul Simons

ON THE evening of October 15, 1987, Michael Fish made his famous announcement on television. “A lady rang the BBC and said she’d heard that there was a hurricane on the way. Well, don’t worry if you’re watching, there isn’t.”

Hours later one of the most devastating storms in British history tore down 15 million trees and killed 19 people.

But Fish was correct — there was no hurricane. Hurricanes are tropical storms which feed off warm seas, and the waters around the UK are too cold for them. Also, a hurricane would have been ripped apart by the strong jet stream winds that were blowing over Britain that night.

Instead, our typical Atlantic storms are driven by a collision of cold and warm air masses along weather fronts, so-called baroclinic systems not present in hurricanes. Another difference is that our storms are boosted by the jet stream. However, when hurricanes die off in the cooler waters of the Atlantic they sometimes are resurrected as vicious versions of our more usual storms. This week the remains of Hurricane Gordon will batter western regions of the UK and Ireland, and the relics of Hurricane Helene may turn up next week with more stormy weather. But by the time Gordon and Helene reach here, their lives as hurricanes will be well and truly over.

From TIMES ONLINE

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September 22, 2006 By Paul Simons

THIS summer was unusually warm in the Arctic. Satellite pictures taken in late August revealed a giant crack in melting sea ice stretching all the way to the North Pole. The channel was so large that a ship could have sailed without difficulty from Spitzbergen or northern Siberia to the North Pole.

The European Space Agency (ESA) discovered that the “dramatic openings” in the polar ice covered an area larger than the British Isles. “This situation is unlike anything observed in previous record low ice seasons,” remarked Mark Drinkwater, of ESA. The melt was caused by unusually high summer temperatures, followed by late summer storms that broke up much of the remaining ice. Colder autumn temperatures have frozen over the open sea, and the giant crack shown in the satellite images appears to have closed up.

Last year marked the smallest area of sea ice ever observed in the Arctic, a decrease of around a third since satellite observations of the region began in the early 1980s. If this melting trend continues, a sea passage will open between Europe and Asia over long enough periods in the summer for ships to sail through, perhaps in the next 10 to 20 years. But the open sea will absorb more solar energy and send temperatures even higher, with potentially devastating effects on the global climate.

From TIMES ONLINE

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September 25, 2006 By Paul Simons

TODAY marks the 160th anniversary of the birth of the meteorologist Wladimir Köppen. His name may not be familiar, but he made some impressive discoveries about the world’s climate, including mapping out the climate regions according to the temperature, precipitation and plant growth, from the hot, humid tropics to the cold polar regions.

He also teamed up with his son-in-law Alfred Wegener to work on a baffling mystery. Why were there traces of ancient ice-caps in rocks near the Equator, while fossils of lush tropical plants were found near the poles? This puzzle seemed to make no sense. They proposed that continents drifted and explained, for instance, why tropical plants once grew in Spitsbergen, now in the Arctic Circle. The theory caused a huge outcry among other scientists and it took decades before it was finally accepted. Köppen and Wegener also worked out that cool summers were crucial for setting off an ice age. If great sheets of ice could persist through a cool summer without melting, then their whiteness would reflect sunlight and help to make the climate even colder. Today, the problem is the reverse with global warming — warmer summers are melting ice-caps, more solar heat is being absorbed in the ground or water underneath, and the climate is growing even warmer.

From TIMES ONLINE

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September 26, 2006 By Paul Simons

THIS winter may be colder than expected. Last week the Met Office revised its winter forecast to advise that it would start off mild then turn colder than average towards the end of winter, around February or March. The reason is the appearance of an El Niño emerging in the Pacific.

El Niño is a lurch in the tropical Pacific seas, as the prevailing winds change direction and warmer waters spread towards Latin America. El Niño varies in intensity, and at its most severe can cause devastating droughts or floods across a large part of the globe. Europe and the UK used to be thought to be too far away to come under the influence of El Niño, but, two years ago, a Swiss team of climatologists discovered that El Niño's influence could indeed reach Europe, and had perhaps helped to change the course of the war. They found that the unusually cold winters of 1940-42 were triggered by an El Niño. The ferocious cold of the winter of 1941-42 was a severe setback in the German invasion of the Soviet Union, when temperatures dropped to minus 40C (-40F), machinery froze and a quarter of a million troops died of cold and disease. On the other side of the world, a strong El Niño had set off disturbances in the stratosphere that surged like a wave, and which are believed to have created the cold in Europe.

From TIMES ONLINE

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September 27, 2006 By Paul Simons

GEORGE AUSTIN, of Wheldrake, near York, wrote to ask why the hours of daylight published in The Times for the autumn equinox on Saturday did not amount to exactly 12 hours, as would be expected.

True, many books say that on the equinox, daylight and darkness are equally 12 hours all over the globe. But on Saturday, the official hours of daylight for London were 12 hours 14 minutes.

It is largely because the Earth's atmosphere plays a trick - it bends the Sun's light, a phenomenon known as refraction. The same explains why your hand appears to bend sharply when you put it into water.

This means that at sunrise, the Sun appears to be on the horizon a few minutes before it actually arrives there. At sunset the Sun remains visible for a few minutes after it has set. Those extra minutes account for the slightly longer day length at the equinox. And the farther north you go, the more marked the difference is. Sunlight refraction is most bizarre in polar regions. In recent years the Inuit in the Canadian Arctic have reported a strange glow on the horizon during the winter, when normally it is dark. It was unusually warm air overlaying colder air and refracting light from the Sun hidden far below the horizon - a vivid demonstration of global warming in action.

From TIMES ONLINE

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September 28, 2006 By Paul Simons

TUESDAY evening in London brought a magnificent display of aircraft contrails criss-crossing the sky, lit up in an orange glow by the setting sun.

Contrails appear at the cruising height of jet aircraft, around 10km (6 miles) high. At this altitude, if the air is humid and temperatures especially cold, the waste water vapour shot out from the jet engines condenses and freezes into ice crystals. In calm conditions, these contrails can develop into feathery wisps of cirrus clouds.

After this topic was aired in Weather Eye last year, a reader asked whether a contrail could turn into a cirrus cloud. In fact, persistent contrails can last for hours, growing to several kilometres wide, and become almost indistinguishable from natural cirrus clouds.

Aircraft contrails also have an impact on climate, quite separate from carbon emissions. They reflect sunlight back into space, which helps to cool temperatures on the ground. But overall they are believed to trap warmth, especially at night, by reflecting heat down to Earth. The problem is so severe in the crowded flight paths over the UK that climatologists at the University of Reading have asked for night flights to be restricted. They estimate that although night flights account for only about a fifth of Britain’s air traffic, they cause up to 80 per cent of the warming effect of all contrails.

From TIMES ONLINE

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September 29, 2006 By Paul Simons

TODAY marks a rare astronomical event: the lunar standstill, at the prehistoric stones of Callanish on the Isle of Lewis, Outer Hebrides. The lunar standstill happens every 18.6 years, when the Moon reaches its most extreme elevations in the sky. It is created as the moon goes around the Earth in a plane just 5 degrees off from the Earth’s orbit around the Sun.

The stones at Callanish were built at least 4,000 years ago and seem to celebrate the lunar standstill with unerring accuracy. This evening the Moon will rise at about 5.10pm at its most southerly position on the horizon, out of a valley in hills called the Sleeping Beauty. It then tracks along its lowest elevation in the sky, appearing to skim along the horizon for some distance before setting among the stones in the central circle of Callanish. However, there may be a risk of cloudy skies, and, in any case, the Moon will be less than half-full, so will not look especially dramatic.

However, a more spectacular chance to see lunar standstill at Callanish will appear in June 2007, when the Moon will be nearly full and almost reach the extremes of tonight’s positions, and hopefully the sky will stay clear. For further details of the lunar standstill at Callanish click here

From TIMES ONLINE

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September 30, 2006 By Paul Simons

WITH recent gales and lashings of rain, it may not seem particularly warm, but temperatures have held up surprisingly well this month. Southerly winds have swept in mild air, and cloudy skies have helped to trap warmth down near the ground, making for some wonderfully mild nights and temperatures above average.

Of course, by no stretch of the imagination could this weather be described as hot. Proper heat waves, however, have been recorded even this late in the year. In 1895 September went out in blistering heat, with temperatures soaring to more than 30C (86F) and broke records. In fact, that late heat wave was so freakish that it boosted the month’s average and made September the hottest month of the year.

The weather pattern in that heat wave featured southerly winds swept up from North Africa, delivered by a large anti-cyclone centred over Europe. It was very sunny, with Eastbourne enjoying 246.8 hours of sunshine that month, and the South Coast experiencing a late boom in holidaymakers. 1895 suffered a long drought and the 1890s had five dry winters, with no chalk streams flowing in the Chilterns by 1896. These days such a prolonged drought would be crippling — if the coming winter is dry the southern half of Britain will be facing serious water shortages next year.

From TIMES ONLINE

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October 2, 2006 By Paul Simons

AFTER a rainy start this month may follow a trend for wet Octobers in recent years. This has become important as winters have turned drier, particularly in the southern half of Britain.

Rainfall from now until March is crucial for replenishing underground water reserves. As temperatures cool off, and vegetation shuts down for the winter, so less water is lost from the ground. This gives the rain a good chance of soaking the ground and trickling down into the rocks deep below. Porous underground rocks, such as chalk and limestone, soak up that rainwater like a sponge, and provide much of the water supplies for southern and eastern regions of England. Without that recharge of water during autumn and winter, these areas will be facing chronic drought next year.

Forecasts for October suggest that after early wet weather, high pressure will build up, giving dry, sunny conditions followed by further bouts of rain towards the end of the month.

However, rainfall at this time has probably always been fickle:

Dry your barley in October,

Or you’ll always be sober.

The folklore saying suggested that farmers had to use any spell of dry weather before rains spoilt the fruits of their harvest.

From TIMES ONLINE

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October 3, 2006 By Paul Simons

STEUART CAMPBELL, of Edinburgh, wrote to ask how a glow seen through the long Arctic winter could be taken as a sign of global warming, as described in Weather Eye last week. After all, he pointed out, this phenomenon is a type of mirage that has been seen throughout history.

True — in the winter of 1597 a ship under the command of the Dutch explorer Willem Barents was trapped in ice over winter off the coast of the Russian Arctic island of Novaya Zemlya. In late January he and his crew were astonished to see a distorted Sun rise above the horizon for a short time. The breaking of the long Arctic night was not expected for another few weeks. Their account was dismissed, but it was actually a mirage of the Sun that was hidden well below the horizon.

This was created by a layer of warm air over colder air, known as a temperature inversion, and created a giant lens in the atmosphere which bent light from hundreds of miles away.

However, for the past ten years, the Canadian Inuit have reported unprecedented periods of light on the horizon in their dark winters. Measurements revealed intense temperature inversions that coincided with a steep rise in Arctic temperatures, and has been proposed as a sign of global warming. More details of the Arctic glow are at: www.eh2r.com

From TIMES ONLINE