Is The Sun Going into Lock-down?
A report about reduced solar activity on the Sun’s surface confirms fears of a doomsday mini-Ice-Age, and asks if it’s about time we saw the light.
Because it turns out even the Sun has gone into a lock-down ‘recession’, or, more accurately, a deep period of ‘solar minimum’.
While members of the Royal Astronomical Society are urging us not to panic and reminding this is just nature, nothing to worry about and the sort of thing that happens every 11 years or so as the Sun passes through its activity cycle, some doom-and-gloomers are much less optimistic.
Perhaps they haunted by the extreme ‘solar minimum’ thought to have contributed to the so-called Little Ice Age in Europe in the 17th and 18th centuries, when the temperatures fell so low the River Thames froze over, crops failed, lightning storms lit up the skies, and — in 1816 — the weather was so crazy that it snowed in July.
What we do know is the teeniest change in solar activity levels can have extraordinary consequences — triggering lightning storms, the appearance or disappearance of the Northern Lights and those amazing sprites.
But the Sun’s activity is changing constantly as it passes through its regular cycle, from solar maximum (hottest and most active) to solar minimum (quieter and cooler).
Since the 17th Century scientists have measured the depths of the solar minimum by counting the number of sunspots or areas of magnetic activity on the solar surface which show up as relatively dark spots, also solar flares which are large explosions that hurl charged particles into space.
The general rule is the fewer the sunspots, the more severe the minimum and the higher the chances of lightning storms, sprites and disruption on Earth.
So far this year, the Sun has been ‘blank’ — with no sunspots — 76 per cent of the time. A figure surpassed just once since the Fifties, last year, when it was 77 per cent blank.
So could we be heading for a grand solar minimum, a sustained period — decades, even centuries — of particularly weak solar cycles?
Are we now — on top of everything else — facing another mini ice Age?
While it might all sound terribly dramatic and end-of-the-world-like, history does tell a salutary lesson.
Two hundred years ago, we were deep in the midst of the Dalton Minimum, which occurred between 1790 and 1830 and was marked by periods of brutal cold.
Temperatures fell by 2c over 20 years, which may not sound much, but had the effect of devastating the world’s food production and causing widespread famine.
The misery was then exacerbated by (unrelated) powerful volcanic eruptions.
Before this came the Maunder Minimum (named after astronomer Walter Maunder), a grand solar minimum which started in 1645, took in the ice fairs on the River Thames during the reign of Charles II and dragged on for 70 years.
During this time scientists observed only 50 sunspots — compared to the 40,000 to 50,000 that we would expect during an equivalent period of ‘normal’ activity.
So it’s a relief to hear from Mathew Owens, professor of space physics at Reading University, that history is not about to repeat itself.
Meanwhile, Met Office scientist Jeff Knight insists that, while a solar minimum does have an effect — contributing to very slightly colder winters (the last minimum between 2008 and 2010 coincided with some colder than usual winters in the UK) — it is very small.
Of course, our prime concern is the Sun continues to shine. But happily, given we have so much on our plates at the moment, we can park that worry for a little while longer.
