The sun has got its spots on - will this bring a bright outlook?
An astrophysicist at Queen’s University Belfast has been reading the pattern of sunspots and solar cycles, writes GERRY MORIARTY,Northern Editor
WE COULD be in for some improved winter weather over the coming years, according to Dr Ryan Milligan. He’s a 36-year-old Queen’s University astrophysicist who was formerly based at Nasa – and who, in his spare time, does road haulage work, just to keep his hand in.
He’s a native of Ardglass, Co Down and a member of a family that has been involved in the fishing business for generations. With a group of other astrophysicists around the globe, he is trying to penetrate the many mysteries of the sun.
He’s something of an inspirational figure, too – particularly for late academic developers. When he did his A-levels he gained two Bs in pure and applied maths and an E in economics – not exactly the sort of grades expected of a future Nasa astrophysicist.
After that result, Milligan did what many students before and since have done – he took some time out. He travelled the world for a while, drummed in rock bands, studied sound engineering, worked in fish factories and coal yards, and also made a living driving lorries after getting his HGV licence. Then, when he was 23, he decided to enrol at Queen’s to pursue a degree in astrophysics, and later with his first-class honours Masters degree was head-hunted by Nasa. His particular focus is on solar flares, massive eruptions or explosions in the sun’s atmosphere, which are becoming more frequent these days due to the increase in the number of sunspots.
“During these explosive events, the sun puts out large amounts of ultra-violet radiation. The earth’s atmosphere absorbs this light and, in effect, puffs up like a balloon. This can have a knock-on effect on satellite orbits, GPS accuracy and radio transmissions,” he says.
His work dovetails well with other worldwide research, where scientists are trying to determine if there is a correlation between the absence of sunspots and extreme winters. The winter before last was one of the worst for decades, causing a freeze that the North’s water authorities couldn’t cope with, leaving some 40,000 households without water for lengthy periods during the Christmas and New Year holidays of 2010/2011. The previous two years weren’t much better.
This called to mind the so-called Little Ice Age when, over a period from 1550 to 1850, there were long-lasting intervals of bitterly cold weather – and when, for lengthy periods there were no sunspots at all. “This was a time when the River Thames regularly froze over and they used to hold ‘frost fairs’ on the river because the ice was that thick,” says Milligan. Since then, scientists have been gathering information on what are called solar cycles, which run on average for about 11 years at a time. We are now in cycle 24, which is expected to peak in 2013/2014.
During these cycles the number of sunspots waxes and wanes but, what was noticeable about the last cycle, as Milligan explains, was that it seemed to drag on longer than normal – and through a period when there was an absence of sunspots and when the winters in Ireland and elsewhere became more severe.
Sunspots are now returning and, with them, the relatively mild winter – such as that just seen in Ireland, notwithstanding the cold snap experienced by other parts of Europe.
Milligan, like most scientists, enters many caveats and warns that specific weather predictions are very difficult to make and that this form of study is in its relative infancy. “We still don’t know what drives the 11-year solar cycles – it is one of the great mysteries of the sun.”
You can also expect more solar storms in the coming years because of the sunspots – and also some more spectacular skies. “We are going to see a lot more solar flares – intense bursts of radiation – and coronal mass ejections – clouds of charged particles that get thrown out – because of the sunspots,” he says.
It is a fascinating study which could have practical applications in terms of long-term weather forecasting and also guarding against solar storms causing major electrical blackouts, which can and do happen. In 1989, a huge solar storm shut down the power grid supplying the Quebec province in Canada.
At Queen’s, Milligan still works very closely with Nasa and has recently published a series of papers on solar flare research in collaboration with Nasa scientists using data from Nasa’s own Solar Dynamics Observatory (SDO) satellite. The space agency has also awarded him a substantial research grant to continue investigating the origins of ultraviolet radiation during solar flares.
New, exciting data on the sun is coming in all the time from Nasa and from other research centres around the world, with Milligan and the Queen’s physics department playing a significant part in that work.
“Hopefully, over the next solar cycle, we’ll get to learn even more,” he says.