Will the solar eclipse create an 'EERIE WIND'? Scientists hope to observe strange impacts of partial eclipse on weather
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The partial solar eclipse on Friday may bring some unusual winds and weather to the UK, according to scientists.
Meteorologists are planning a country-wide experiment to observe impacts of the partial eclipse, which will see between 84 and 94 per cent of the sun above Britain being obscured by the moon.
Researchers say the phenomenon will give them a rare glimpse at how the sun influences the clouds and wind.
The partial solar eclipse, like the one above, is due to block out up to 97 per cent of sunlight in northern Europe as the moon moves across the face of the sun and casts a shadow over the Earth on Friday 20 March
A previous study on the last major solar eclipse to occur in the UK in 1999 has provided some tantalising hints to what will happen.
Researchers have found that temperatures dropped by up to 3°C during the transition of the moon in front of the sun.
They also saw winds change direction and drop in speed during the hour long eclipse.
This they claim could be what causes anecdotal reports eerie 'eclipse winds' from observers.
Onlookers in Cornwall in 1999 - the only place in the UK where a total eclipse was visible - reported feeling mysterious winds.
Professor Giles Harrison, an atmospheric physicist and his colleague Dr Suzanne Gray, both at the University of Reading, found there really were subtle changes in the wind during the 1999 eclipse due to the fall in temperature.
The eclipse on Friday is likely to produce a smaller drop in temperature as it is happening early in the morning before the heat of the sun is felt.
Forecasters have also said that much of the country is likely to be covered with cloud, meaning air temperature drops are likely to be subtle.
This graph shows how air temperatures in the UK dropped during the 1999 solar eclipse, leading to changes in wind speed and wind direction - helping to explain some of the strange weather associated with eclipses
However, Professor Harrison said that observers could still expect some unusual weather activity.
He said: 'There are several accounts of an 'eclipse wind', a change in the breeze as the eclipse reaches its greatest extent, but we've never had enough data to definitively prove or disprove its existence before.
'While we have more data now than ever from weather stations and satellites, we still need people to provide their own observations, particularly to tell us about cloud cover.
'This could also help to establish if breaks in the cloud are common during the peak of an eclipse.'
A total solar eclipse like the one above will only be visible from Greenland and up towards the Arctic circle
Professor Harrison and his colleagues have set up the National Eclipse Weather Experiment to ask members of the public to record minute by minute weather changes - including air temperature, wind speed, wind direction and cloud cover - during the eclipse on Friday morning.
The data they gather will help to build on a study they carried out in 2012 on the weather conditions that occurred during the 1999 solar eclipse.
They used computer models to examine how the weather would have behaved without the eclipse and compared it to meteorological observations.
They found that the temperature dropped by around 3 degrees C compared to what the model predicted and on average regional wind speeds dropped by 1.5 mph.
The wind also changed direction in an anticlockwise direction by as much as 17 degrees.
Professor Harrison and Dr Gray said that the changes appeared to match theories that a drop in temperature caused by the eclipse created 'cold cored cyclone' conditions which may explain reports of an 'eclipse wind'.
This Friday's eclipse is expected to start around 8.24am in London and will peak at around 9.31am when the moon will cast its biggest shadow over the Earth.
On 20 March, the moon's orbit will see it travel in front of the sun, casting a shadow over Earth. It is due to end at 10.41 am.
The most 'complete' eclipse in the UK will be see from Lerwick in the Shetland Isles seeing 97 per cent of the sun being covered by the moon.
Glasgow, Aberdeen and Edinburgh will see 94 per cent of the sun being covered while London will see 84 per cent and Manchester will see 89 per cent covered.
Skies are expected to darken visibly in any location where the maximum obscuration exceeds 95 per cent.
This could mean that drivers in north-west Scotland, the Hebrides, Orkney and Shetland Islands will have to turn on their headlights.
Professor Harrison said they hoped to the eclipse would provide the research team with new data on how the phenomenon can influence the weather and may even help to explain the momentary breaks in cloud cover that can occur during eclipses.
He said: 'The eclipse is like a controlled experiment with the atmosphere, so we can test theories and models with these findings.
'By observing what happens on Friday we are effectively turning the skies of Britain into a giant weather lab, giving us a rare chance to see what happens when you 'turn down the sun'.
'This will give us a precious insight into how the sun influences the clouds and wind, as well as more obvious effects, such as temperature.
'By improving our understanding of how the weather works, we're better able to predict it, meaning scientists can further improve weather forecasts.'
'We learned a lot from the 1999 eclipse weather measurements, but, as Friday's event is the first UK eclipse of the social media era ,there should be a much richer source of detailed measurements.
'At this point though, where the cloud will be is still a real cliff hanger.
'There could be some broken cloud in the south of the UK. For some folk then it might prove a great week for the spectacles of natural science, seeing both the aurora and an eclipse.'
Looking at the sun during an eclipse can cause long-lasting and sometimes permanent damage to the eyes so those hoping to watch it happen are being urged to wear eye protection and not to look directly at the sun
The Met Office has warned that much of the UK could struggle to see the eclipse as it may be obscured by cloud.
A spokesman said that the south west of the could have the clearest skies on Friday morning and has the best chance of seeing the partial eclipse.
She added that while the eclipse might bring a noticeable drop in temperature, it is likely not to be significant.
Health authorities have also issued a warning to sun-gazers hoping to catch a glimpse of the eclipse.
They warned that people should not look directly at the sun and should only use special protective glasses.
Those hoping to catch a glimpse of the partial eclipse have been warned not to look directly at the eclipse but to either wear adequate eye protection or to watch it by projecting it onto paper like in the photograph above
The eclipse in 1999 saw hundreds of people attend hospital with eye damage after staring at the sun.
A study in Nature showed that 15 people in East Sussex had 'deep white spots' in their viesion that took three months to clear up.
Four patients in Leicester still had blurred spots in their vision more than seven months.
In 1984 the Royal Manchester Eye Hospital reported that 11 people suffered permanent eye damage after a partial eclipse.
Dr Susan Blakeney, NHS England optometric adviser, said: 'Looking at the sun can cause solar retinopathy. Very strong radiation can cause permanent damage to the back of the eye, like a scar or a burn.'
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