highcliffe2
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BY PAUL SIMONS
BRITAIN is one of the windiest places on Earth. In a global survey of wind speeds, some of the highest average wind speeds, over 33kph (21mph), were found in parts of north and west Scotland, northwest and southwest England. These areas are regularly battered by depressions sweeping off the Atlantic and have enormous potential for generating electricity by wind power.
Researchers at Stanford University took data from around the world and calculated average wind speeds at 80m (262ft) above the ground, the height needed for wind turbines to work.
They found that there are enough windy places to make five times the entire world energy needs from wind power alone. Of course, it would be uneconomic or highly contentious to site wind turbines at every suitable location, especially in areas of natural beauty. Nonetheless, the potential for wind power remains enormous.
Apart from the UK, the world’s other windiest regions are sited along the European coast of the North Sea, the southern tip of South America and Tasmania. But the strongest winds of all are found in North America, around the Great Lakes and along the coastlines of the Pacific, Atlantic and Gulf of Mexico. The US has the windiest location at Mount Washington, New Hampshire, which also holds the world record for the highest wind speed: 372kph (231mph) logged during a storm on April 13, 1934.
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BY PAUL SIMONS
THE monsoon has arrived in the Andaman Islands of the Indian Ocean, slightly later than normal, and is due to hit India early next month.
The Indian monsoon is the largest and most regular weather system in the world, and its driving force was figured out more than 300 years ago by Edmund Halley, best known for his comet studies.
In 1676, when Halley was 20 years old, he quit Oxford University for a voyage to the South Atlantic to study the stars of the Southern Hemisphere. During the voyage Halley wondered why the strong trade winds of the tropics seemed to die away around the Equator, a region that sailors called the doldrums.
Halley realised that the Sun heated the Earth’s surface more at the Equator, making warm air rise and creating the doldrum’s slack winds. Eventually that air from the Equator fell to Earth far away and returned as the trade winds.
The Sun also heats the Indian subcontinent in summer, making hot air rise up over the land. But the surrounding sea takes much longer to heat up, and its cooler, moister air is sucked inland as a monsoon wind that sets off huge rainfalls.
A small-scale version of that wind also happens at the seaside. As the coast heats up during the day it sucks in cool air off the sea and creates a refreshing sea breeze.
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BY PAUL SIMONS
YOU may be fortunate over the next several weeks to see something quite magical after sunset — threads of glowing silvery-blue clouds stretched across the night sky.
These are rare “night-shining” or noctilucent clouds. They are the highest clouds in the world, about 80km (50 miles) high in the layer of atmosphere called the mesosphere. This is the coldest place on Earth, where temperatures can plunge to minus 130C (-200F), and where it is about a million times drier than the Sahara.
So how do noctilucent clouds form in such a dry environment? The tiny amount of water vapour that is floating about in the mesosphere is turned into ice crystals by the incredible cold.
The ice crystals also need to form around specks of dust, which might come from the smoke particles left by meteors (shooting stars) burning up in the mesosphere.
Strangely, the first sightings of noctilucent clouds were made only in the 1880s, and largely occurred in polar regions. But in the past 20 years they have become more frequent, spread further from the poles and turned noticeably brighter. These may be telltale signs of global warming, because, paradoxically, the mesosphere is turning colder as the lower atmosphere heats up.
The best time to see noctilucent clouds is after the Sun has dipped well below the horizon; they are seen mostly in the northern sky and in very clear conditions.
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BY PAUL SIMONS
ON THIS day in 1965 Britain took an early step towards going metric. Long before we joined the Common Market, and under pressure from British industry, the president of the Board of Trade, Douglas Jay, told Parliament that we should adopt the metric system. But 40 years later we are still in a mess, juggling metric and imperial units in shopping, sport, weather forecasts and almost everything else in daily life.
In fact, the first proposal to make Britain metric was advanced by a select committee in 1862. But Britain was suspicious of metrication — it was, after all, born out of the French Revolution.
Temperature scales, though, were different because fahrenheit and celsius were invented long before the metric system. Daniel Fahrenheit — who was born on this day in 1686 — developed his temperature scale in 1709 and based it on the temperature of a healthy man, a reading recognised today as 98.6 degrees. He then made 180 degrees between the freezing and boiling points of waters. But when the simpler 100-degree scale of Anders Celsius was invented in 1742, it rapidly gained popularity throughout Europe.
Fahrenheit still clings on in Britain, however, even though converting between the two temperature scales is clumsy and makes our weather page more complicated.
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BY PAUL SIMONS
“NE’ER cast a clout till May be out” goes the old saying, meaning: “May can be surprisingly nippy, so don’t take off your woolly clothes until the end of the month”.
The strange thing is that the daylight hours in May are long and the sun climbs high in the sky, so you might imagine it should feel like summer. But the seas around the UK are still very cold, northerly winds can whistle down from the Arctic, and at night the land rapidly loses heat under cloudless skies and lets frost take hold.
Perhaps the best region in the UK to enjoy May weather is the West Coast of Scotland. There this is the driest and sunniest month on average, with the bonus that the midge season has not begun yet.
The westerly airflows that sweep off the Atlantic and often drench this region tend to be slack in May; instead, the region is sheltered by the Highlands from cold easterlies blowing off the Continent. The air also tends to be very dry, although that carries the threat of wildfires; last week fire took hold in the Loch Ard Forest in the Trossachs.
Last May was even more spectacular: western Scotland was roasted in a heatwave with temperatures soaring to 22C (72F) in Glasgow, leaving many Mediterranean holiday resorts in the shade.
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BY PAUL SIMONS
PRESIDENT George Bush was bundled into an underground bunker, the Vice-President was evacuated to an undisclosed secure location, and heavily armed servicemen took up defensive positions. On April 26, the White House appeared to be under attack when radar picked up intermittent blips from an approaching object moving through restricted airspace at about the speed of a helicopter. But the “target” turned out to be a fast-moving rain cloud scudding towards the White House. At the time, there were light rain showers with a gentle wind.
There is an irony that radar designed for security could detect clouds by mistake, because this is how radar originated — as a weather service in the First World War. Pilots were being battered by thunderstorms in their flimsy aircraft, and the Scottish physicist Robert Watson-Watt devised a warning system by tracking the radio interference from distant thunderclouds. It was only much later, in the 1930s, that he refined his system to pick up aircraft.
Radar does not actually “see” clouds as such, because the droplets in the clouds are too small to reflect radar beams. Instead, the signals bounce off larger drops falling from clouds, and the bigger the raindrop, the better the radar signal, as shown by brighter colours on the displays. And the problem of interference also works the other way — weather radar sometimes get confused with echoes from aircraft.
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Torrential rain this morning, being right on the coast it looks like we are missing the worst of it
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BY PAUL SIMONS
AUSTRALIA could face a shortage of steak and lamb over the coming months or even years. A crippling drought has gripped almost half the country’s farmland and it has suffered its driest four-month period and hottest April since records began in 1910 — and things look likely to get worse.
Australian meteorologists are warning that a new El Niño could be about to bite. This climate phenomenon sends wind and ocean patterns across the Pacific into turmoil: colder waters drive towards Australia, bringing dry winds, while warmer waters shunt eastwards to North and South America, delivering torrents of rain. The warning signs are growing clear. This winter heavy rains fell in the US Southwest. Los Angeles was flooded, the deserts of California and Arizona bloomed with wildflowers, and huge snowfalls in the Sierra Nevada mountains gave ski resorts one of their best seasons.
Although these events were dramatic, it was thought that El Niño would fizzle out soon. But now there are alarming signs of a resurgence as the South American coast is now about 2C (3.6F) warmer than average, and rainfall is shifting away from Australia towards the central Pacific.
This comes as many farmers in Australia are still recovering from the last bout of El Niño drought in 2002-03, dubbed “the big dry”. The long-term outlook is even bleaker as climate change is expected to turn Australia even drier.
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BY PAUL SIMONS
THE northern lights have made some dramatic appearances this year. Last weekend large swaths of North America were treated to ribbons of coloured light streaming across the night sky; unfortunately we missed out because the aurora came during daylight hours in the UK. Even more spectacularly, two X-class solar flares — the largest type of solar explosions — erupted in January, spawning auroras as far south as Arizona in the US.
Strangely, the textbooks say that auroras are not expected at the moment. The Sun goes through a cycle of about 11 years during which the numbers of its sunspots — seen as black specks on its surface — rise and fall. Sunspots are signs of furious eruptions from the Sun’s surface, spewing out massive clouds of electrical charges. As these explosions hurtle through the solar system they batter the Earth with electromagnetic energy that sets off aurora displays. The storms can also knock out satellites and disrupt power supplies on the ground.
Next year the sun will reach the quietest part of its cycle, when few sunspots, solar storms and auroras are expected. However, the Sun is very active at the moment, and these bursts of activity show that the idea of the solar minimum is something of a myth, and that the Sun can erupt at almost any time.
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BY PAUL SIMONS
IT IS difficult to know what to wear at the moment with temperatures oscillating wildly between cold and warm days. In fact, May is a transitional month between winter and summer, and it can even snow.
Fifty years ago today almost the whole of Britain was gripped by a ferocious blizzard whipped up on a northerly gale; it was more like the depths of winter than late spring.
Snow ploughs were called out as high-level roads across the Pennines, Peak District and South Wales were blocked. Even cities were overwhelmed. Sheffield had 10cm (4in) of snow and Birmingham had 2.5cm. In London it snowed for three hours during the night — it was the last time that substantial snow fell on the capital in May.
The warning signs of the dreadful weather had come a few days earlier as bitter cold and frosts took grip. By May 14 snow and sleet were falling, and on May 16 the thermometer plunged to -4C (25F) at Lincoln. The following day the snowstorm burst south from Scotland and eventually it reached parts of the South Coast.
The freezing spell ended on May 22, and bouts of cold returned in June. But there was some consolation — July, August and September were gloriously hot and sunny.
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BY PAUL SIMONS
TWO weeks ago, on Bank Holiday Monday, you may have noticed cars and windows covered in dust. A sandstorm over the Sahara a few days earlier had lifted up fine particles of sand, with the consistency of talcum powder, which were swept over on high-level winds and dumped over southern Britain in light rains.
The Sahara is the largest source of the dust floating in the atmosphere, and it is blown over Britain several times a year. Apart from leaving dirty windows and cars, this dust also plays a key part in the global climate. When the dust falls into oceans it helps to fertilise the seawater with iron. This stimulates the growth of phytoplankton — tiny organisms that feed on carbon dioxide for their photosynthesis — and so helps to reduce the greenhouse effect. The Saharan dust even blows right across the Atlantic to Amazonia and fertilises the soils there.
The dust helps to stop hurricanes forming in the North Atlantic, and helps to cause violent thunderstorms in Florida — where it also creates spectacular sunsets.
Because the clouds of dust shield out sunlight, they cool the atmosphere below, which should help to cut global warming. However, Nick Brooks at the Tyndall Centre for Climate Change Research in Norwich has found that this cooling effect tends to suppress seasonal rains in the Sahel region, thus provoking the droughts that frequently devastate the area.
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BY PAUL SIMONS
WHAT will this summer be like? There has been much speculation in the media in the past few days that we can expect a scorcher.
This is based, it seems, on a long-range forecast by the Met Office. In fact, the seasonal forecast from the Met Office had said no such thing — it merely pointed to the “chance” of above-normal temperatures, but said that at this stage it is impossible to predict much else.
The excitement highlights the problem of how we should treat long-range forecasts. These are very inexact predictions, far removed from the daily weather forecasts, and should be taken with caution.
They are based largely on the temperatures of the oceans, which soak up vast amounts of heat — just the top 3m (10ft) of the Earth’s oceans contain more heat than the entire atmosphere. Because that heat is released slowly, like a colossal storage heater, forecasters can deduce what might happen to temperatures and rainfall months ahead. An unusually warm or cold body of seawater in an ocean, for instance, could be a sign of significant changes in weather to come.
Great strides have been made improving these seasonal forecasts using a fleet of robotic buoys spread around the world’s oceans. But they are still a long way from a proper weather forecast.
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BY PAUL SIMONS
OUR summers are gradually getting hotter, and heatwaves growing more intense. On Tuesday night a BBC One programme, Heatwave, imagined the consequences if Britain were struck by a heatwave similar to that in continental Europe in 2003, when more than 27,000 people died because of the high temperatures.
The programme showed hospitals overflowing as thousands of people died, mostly elderly and sick, while the transport system buckled and wildfires ran out of control.
Unfortunately, the script given to the actors playing the so-called experts was littered with appalling science, such as “When you get a high pressure and you get a low pressure and you put them together, then . . . bang!” If true, Britain would endure endless bouts of exploding weather, as we are often buffeted by high and low-pressure systems.
Strangely, the programme overlooked possibly the greatest problem with a severe heatwave — what happens if everyone buys air conditioners. The National Grid would be unable to cope with the enormous power demand, and the country would suffer severe power cuts, as has happened in California. Ironically, if electricity continues to be generated by fossil fuels, any increased power demand will pump out yet more carbon dioxide, and so increase global warming and bring more heatwaves.
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BY PAUL SIMONS
HAVE you ever taken a day off work because the weather was too bad? According to a new study, it seems that a great many absences from work can be blamed on the weather.
Absenteeism was studied at a clothes factory in North Carolina over several years and it was found, predictably, that cold weather, heavy rain or snow led to an increase in absenteeism, possibly because it was uncomfortable or more difficult to get to work.
But there were some unexpected results — hot or humid weather seemed to have no effect on attendance, but changes in atmospheric pressure were important. According to the report, in this month’s International Journal of Biometeorology, some weather conditions could aggravate health complaints. Heart problems and strokes are known to be triggered by winds or very cold weather, and changes in atmospheric pressure can set off pain such as in arthritis, migraine and bad backs, all common causes of absenteeism.
The Confederation of British Industry calculated in 2002 that an average of about eight days were lost by each employee every year, adding up to a national cost of £11.5 billion.
Although the weather may account for only part of this absenteeism, weather forecasts might be used for predicting how many people will turn up for work each day.
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BY PAUL SIMONS
THE next three days could be nerve-racking for gardeners thinking about planting out tender seedlings — we are now in a chilly spell of weather known as the “ice saints’ days” which has a reputation for cold northerly winds and frosty nights.
Folklore says that an unusually cold bout of weather strikes from May 11 to May 13, celebrating the feast days of three saints, Marmertus, Pancras, and Serviatus, respectively.
In Germany the frost was delivered by Eismänner, or ice men, who visited on these days, and people believed it was never safe to plant crops until the Icemen were gone. In England many sheep farmers avoided shearing their flocks at this time, as an old saying goes: “He who shears his sheep before St Serviatus’ day, loves his wool more than his sheep.”
But is there any truth to this ancient tradition? The UK’s lowest May temperature, –9.4C (15F), was recorded on May 11, 1941, in Thetford, Norfolk, but that could be put down to coincidence. A more chilling picture comes from a look back over the last century, with around 60 per cent of the years recording unusually cold spells in the middle of May, including snow on nine occasions.
This week is no exception, with widespread frosts across many parts of Britain and a northerly airflow blowing down from the Arctic. But long-range forecasts do predict warmer weather by the end of the month.
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BY PAUL SIMONS
WHEN the American poet James Lowell (1819-91) called May “A ghastly parody of real Spring / Shaped out of snow and breathed with eastern wind”, he was spot on.
Despite the long hours of daylight and periods of brilliant sunshine, the weather this month can have a decidedly chilly feel to it in Britain, as well as North America.
The past few days have had a nasty nip, even bringing flurries of snow over the Scottish Highlands. For most of the UK the nights have been particularly cold under clear skies, as heat escapes from the ground and brings temperatures dipping below freezing. Added to that, a chilly airflow is feeding down from the Arctic on the flank of a large low-pressure system sitting over Scandinavia.
The problem at this time of year is the temperature of the sea. Although the land is rapidly growing warmer under the sunshine, it takes far longer for the seas around around Britain to warm up, rather like waiting for radiators to turn warm after central heating is turned on.
So, when the air comes down from the Arctic it is sweeping over chilly seas and has had little chance to warm up by the time it reaches our shores.
Hence the need for warm clothes and bad news for gardeners hoping to risk tender young plants outdoors.
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BY PAUL SIMONS
CROCODILES are living in the Sahara. This sounds bizarre, but several small groups of crocodiles are living in parts of Mauritania, in the western Sahara, where occasional rains fill up pools of water in which the crocodiles can feed on fish. But when the weather grows too dry and hot, the reptiles slip into a summer “hibernation”, known as aestivation, taking shelter in caves, burrows and under rocks.
The Saharan crocodiles are far smaller than other crocodiles, about 5ft long, possibly because there is not much food for them most of the year, so they grow slowly and reach small sizes.
They are the relics of a huge population of crocodiles that roamed the Sahara several thousand years ago when it was a lush region. Thanks to a slow wobble in the Earth’s axis, the northern hemisphere was bathed in more solar energy during the summer months, helping to drive monsoon rains further north into the Sahara. The land turned into a grassy savannah, with shallow lakes and rivers, animals such as elephants and rhinos, and probably looked rather like the big game reserves of Kenya today.
But some 5,000 years ago, as the Earth’s axis gradually shifted, the monsoons grew weaker and the Sahara turned into a desert. Most wildlife died or migrated, but a few crocodiles took refuge in the last pockets of water and survived.
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BY PAUL SIMONS
IF YOU are reading this with a glass of lager, or any other fizzy drink, then you have before you the makings of a fascinating lesson in how clouds are formed.
If you watch streams of bubbles rising to the surface of the drink, notice how they do not form willy-nilly, in some random order. Instead, the bubbles tend to appear on tiny cracks or particles on the surface of the glass, or particles floating around in the beer itself.
These centres of bubble formation are called “nucleation sites”, and a similar seeding process happens in clouds. When water condenses from a gas into cloud droplets it needs tiny particles in the air to grab hold of in order to develop and grow on. These particles tend to be dust, salt or any bits just the right size floating around in the atmosphere.
This is the principle behind cloud seeding, trying to make clouds form extra water droplets so that they rain in drought-stricken areas. Favourite cloud seeding agents are silver iodide or common salt, and you can try a similar seeding process for making bubbles in your drink.
If you can bear the thought of ruining beer, try sprinkling a big pinch of salt into the drink and watch it create a cloud of bubbles. The same happens with fine sand, but this may be taking the experiment too far in the interests of science.
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Hi Kelly, good to see someone from nearby
The conditions are of course almost the same as Kelly, very pleasant and the breeze is helping cool things down too. Looking at weatheronline and xcweather, it has maxed out around 16/17ºc, which is perfect for me
It looks like continuing into the weekend too
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BY PAUL SIMONS
FIFTY years ago, East Anglia experienced one of its worst dust storms, reminiscent of the infamous dustbowls of the American prairies in the 1930s.
Springtime across East England in 1955 had been unusually dry, including a heatwave at the end of April, and reduced topsoil to a crumbly dust. Then a severe gale with winds gusting to 65mph began on May 4 and lasted two days. The soil was whipped up into a vast black cloud of choking dust. Day turned into night as the sun was blotted out and visibility reduced to just a few yards in some places. Dykes and ditches were filled with dust reaching 6ft deep and houses were blasted with black dirt that blew inside through gaps around windows and doors.
“It has been like driving in a thick fog,” described one driver in the Eastern Daily Press, and farmers reported losing thousands of acres of crops and tons of valuable soil.
Dust storms in this region are known as “fen blows”, and although nothing like the scale of the American dustbowls, they cause serious damage to the soil. The fens were originally ancient marshlands and after centuries of drainage produced a peaty soil that turned increasingly dry, crumbly and shrank. As a result, the soil is highly susceptible to erosion and may well disappear completely as the climate becomes dry in decades to come.
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BY PAUL SIMONS
THE wind has been blamed for causing a range of medical complaints, from migraines to heart attacks, but finding hard scientific proof of a link has been difficult. Now, however, a new study has found a clear connection between a desert wind and an infection.
Every year Mali and the surrounding region of West Africa is hit by an epidemic of meningitis; a highly contagious disease, it affects up to 200,000 people, particularly children.
The climate of the region has two principal seasons — a rainy monsoon and a dry season, when a viciously hot and dusty wind, the harmattan sweeps down from the Sahara.
The study, which lasted several years, found that the harmattan usually reaches its most savage intensity in the second week of February — which is just when the meningitis outbreaks begin. The number of meningitis cases drops rapidly as soon as the rainy season begins, in April.
The wind appears to help the spread of the disease by damaging the mucous membranes in the throat and lungs, helping the bacterium to invade the bloodstream and so trigger meningitis.
Thanks to this finding, it may be possible to provide an early warning of meningitis epidemics in this region and thus help to limit their impacts.
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BY PAUL SIMONS
THE recent thunderstorms brought more than just dazzles of lightning. The weather chatroom ukweatherworld.co.uk received an eyewitness report of a strange glowing light on Sunday in Basingstoke, Hampshire.
The witness described how his car roof was covered in “a misty blue-looking gas hovering about 5-10in and a sound of needles dropping on a floor”. At the time, there was intense lightning, heavy hail and rain, and the air seemed to be electrified: “The feeling I was getting in my body was a tingling sensation in the end of my fingers,” he added.
This was almost certainly a case of St Elmo’s fire. It was often seen in the rigging and masts of sailing ships, as Shakespeare described in The Tempest, when Ariel, the sprite, speaks of fooling with unlucky sailors: “I flam’d amazement. Sometime I’d divide,/ And burn in many places; on the topmast,/ The yards, and bowsprit, would I flame distinctly.”
St Elmo’s fire is a plasma, an electrified gas. It usually forms when the air is intensely electrified during a thunderstorm and a large charge builds up around the tips of pointed objects, such as ships’ masts or even the horns of cattle and policemen’s helmets. It ranges from a dancing flame to something like fireworks, often coloured blue or bluish-white, sometimes with a hissing sound.
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BY PAUL SIMONS
SEVERAL newspapers reported last week an apparent blunder by the Met Office’s new supercomputer. The recently installed £27.5 million NEC SX-8 was heralded as a big improvement in weather forecasting, and for Sunday, April 24 it predicted a thoroughly wet afternoon over London. But instead the skies remained gloriously blue and warm.
The press claimed this was a big mistake, but was it? Heavy rains did sweep up from the south, although the stormclouds moved more slowly than expected and did not reach London until night. The mistake was the timing of the rain, not where it would fall — small comfort, though, for anyone who cancelled a barbecue.
The new computer looks at the weather in much greater detail than its predecessors. It works with a grid of squares whose sides are 4km long — this yields a vastly greater resolution than the 12km squares used previously. But at this level of detail, it is possible to miss small upsets in the atmosphere which can sometimes build up into much bigger problems, leading to forecasting mistakes.
But if the entire Earth and its atmosphere were monitored by weather sensors, these tiny local upsets would be found and make forecasts — at least in the short term — incredibly accurate. That is the holy grail of weather forecasting, and with its new computing power the Met Office has taken a big stride towards it.
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BY PAUL SIMONS
ON THIS day in 1775 Benjamin Franklin completed the first scientific study of the Gulf Stream.
It began with a puzzle: why were British mail ships taking days or weeks longer to cross the Atlantic than heavier American merchant ships?
The British authorities sought an answer from Benjamin Franklin, postmaster general of the American colonies at that time. Franklin consulted Timothy Folger, a sea captain on a whaling ship, who described an Atlantic current called the Gulf Stream. The current swept northwards from the warm waters of the Gulf of Mexico, and American ships used it to sail faster to England but avoided it on the return journey. He added that the whaling ships occasionally crossed the current and met British ships struggling to sail against it, but their captains refused the advice of “simple” Americans.
Folger drew a sketch of the Gulf Stream, but when Franklin had it printed and presented to the British the chart was ignored.
Franklin, though, was intrigued by the Gulf Stream, and in 1775 he mapped it on a journey from England to America. He found that the current was some 3.5C warmer than the surrounding sea, and by taking regular temperature readings of the water could trace its course.
“The thermometer may be an useful instrument to a navigator,” he wrote, also noting that the water colour and the seaweeds changed in the current.
Wednesday 01st June 2005
in Weather reports
Posted
Pretty chilly Pete, was there any frost around last night?
Cloudy here currently, and any rain we do get is likely to be light and patchy.
Temperature: 12ºc
Feels like: 12ºc
Humidity: 94%
Dew Point: 11ºc
Wind: 12 mph S
UV Index: 1 Low
Visibility: 3 miles
Pressure: 30.21 in and steady
Sunrise: 4:59 AM
Sunset: 9:11 PM
As reported at Bournemouth, United Kingdom last updated 6/1/05 9:20 AM Local Time