A DROP in temperature is being predicted over the next few decades as experts anticipate an extended period of low sunspot activity will lead to cooler climes over some parts of the Earth. Sunspots normally follow an alternating cycle of 11 years of high activity followed by 11 years of low activity – both of which are believed to impact the planet's weather in a complex and not entirely understood way. The periods are known as the solar maximum and the solar minimum and scientists - sucha s those at the US National Center for Atmospheric Research - say that usually the fewer the sunspots the colder the weather. Occasionally, for reasons which are not entirely clear, the 11 year cycle can extend for decades.


And experts at Northumbria University are predicting the current period of 'colder' low sunspot activity will be a super long one. The last significant extended period of low sunspot activity hit Earth in the second half of the 17th century and is known as Maunder Minimum after the contemporary sunspot experts Annie and Edward Maunder. Research produced by US space agency NASA indicates the Maunder Minimum corresponded with cooler temperatures across the Northern Hemisphere – though some scientists say the temperature fluctuations could have been triggered by volcanic activity. In 2006, NASA said: “From 1650 to 1710, temperatures across much of the Northern Hemisphere plunged when the Sun entered a quiet phase now called the Maunder Minimum.” Climate scientist Drew Shindell and colleagues at the NASA Goddard Institute for Space Studies suggested this was because lower levels of ultraviolet radiation from the Sun, thanks to the sunspots, resulted in less ozone being created in the stratosphere. This decrease in ozone then affected so-called planetary waves and altered the Jet Stream bringing the colder weather and harsher winters of Arctic climes further south into Europe.

The Maunder Minimum actually lasted between 1645 and 1715 and in that 70 year stretch, temperatures in parts of the northern hemisphere dropped by 0.2C. The figure sounds small but many scientists have warned the Earth is susceptible to even tiny fluctuations in temperature. According to the US National Oceanic and Atmospheric Administration (NOAA) the the average global temperature has increased by only 0.8 degrees Celsius over the past 100 years yet that has been enough to trigger claims of climate change catastrophe. And the team in Northumbria are convinced the planet is now facing a second Maunder Minimum. The researchers stated in the study published in the journal Nature (in the sub-section scientific reports): “Waves generated in inner and outer layers of the Sun indicate that the solar activity is heading in the next three decades (2019–2055) to a Modern grand minimum similar to Maunder one.” Valentina Zharkova, lead author of the research and professor in mathematics at Northumbria University, added that this will lead to a temperature drop. Prof Zharkova told Express.co.uk: “Yes, [a temperature drop] will happen. There will be a slight drop with it hitting the lowest in about 30-40 years.”

How the sun looks during a solar maximum (L) and minimum

Advertisement