Is a mini ice age on the way? Scientists warn the Sun has 'gone to sleep' and say it could cause temperatures to plunge

  • 2013 was due to be year of the 'solar maximum'
  • Researchers say solar activity is at a fraction of what they expect
  • Conditions 'very similar' a time in 1645 when a mini ice age hit  

The Sun's activity is at its lowest for 100 years, scientists have warned.

They say the conditions are eerily similar to those before the Maunder Minimum, a time in 1645 when a mini ice age hit, Freezing London's River Thames.

Researcher believe the solar lull could cause major changes, and say there is a 20% chance it could lead to 'major changes' in temperatures.

Sunspot numbers are well below their values from 2011, and strong solar flares have been infrequent, as this image shows - despite Nasa forecasting major solar storms

THE SOLAR CYCLE

Conventional wisdom holds that solar activity swings back and forth like a simple pendulum. 

At one end of the cycle, there is a quiet time with few sunspots and flares. 

At the other end, solar max brings high sunspot numbers and frequent solar storms. 

It’s a regular rhythm that repeats every 11 years.

Reality is more complicated. 

Astronomers have been counting sunspots for centuries, and they have seen that the solar cycle is not perfectly regular.

'Whatever measure you use, solar peaks are coming down,' Richard Harrison of the Rutherford Appleton Laboratory in Oxfordshire told the BBC.

'I've been a solar physicist for 30 years, and I've never seen anything like this.'

He says the phenomenon could lead to colder winters similar to those during the Maunder Minimum.

'There were cold winters, almost a mini ice age. 

'You had a period when the River Thames froze.'

Lucie Green of UCL believes that things could be different this time due to human activity.

'We have 400 years of observations, and it is in a very similar to phase as it was in the runup to the Maunder Minimum.

'The world we live in today is very different, human activity may counteract this - it is difficult to say what the consequences are.'

 Mike Lockwood University of Reading says that the lower temperatures could affect the global jetstream, causing weather systems to collapse.