Scientists say sun may become 7% cooler by 2050, warn of mini ice age

Moneycontrol News

On the basis of 20 years of observations and collected data, scientists have calculated that the sun will be nearly seven percent cooler and dimmer by 2050, which could result in a mini ice age.

A research team based at the University of California in San Diego believes that they have figured out a way to track the sun’s 11-year-cycle.

The sun moves through an 11-year-cycle where it experiences active and quiet periods, known as the solar maximum and solar minimum. The researchers believe they have worked out when the next solar minimum could occur.

During a solar minimum, the sun’s magnetism decreases, fewer sunspots form and less ultraviolet radiation makes it to the surface of the planet. The conditions mean the sun’s surface appears clearer and becomes dimmer.

According to the study, conditions in the next cold period, labelled as a “grand minimum”, could be similar to those experienced in Europe in the middle of the 17th century. Back then, the River Thames froze as a result of the extremely low temperatures.

Low temperatures also caused the Baltic Sea to freeze in 1968. Scientists claim that the period, known as the ‘Maunder Minimum’ was similar to a mini ice age. The head of the research team, Dan Lubin, believes we may experience even worse conditions in 2050.

According to media reports, the research team believes there is a “significant probability” of a near-future grand minimum considering the downward sunspot pattern in recent solar cycles, which is similar to the period prior to previous grand minimum events.

By their estimates, the grand minimum would most likely cool the earth by about 0.25 percent between 2020 and 2070. As a result, the surface of the earth would cool by up to several tenths of a degree Celsius, which is not enough to reverse the impact of global warming but could dilute its effects for a while.

The study said that when the sun’s energy is reduced, the first thing that occurs is the thinning of the stratospheric ozone layer.

"That thinning in turn changes the temperature structure of the stratosphere, which then changes the dynamics of the lower atmosphere, especially wind and weather patterns," it noted.

According to the study, despite the cooler temperatures, this will not put a stop to climate change, however, it could slow down the effects.

“The cooling effect of a grand minimum is only a fraction of the warming effect caused by the increasing concentration of carbon dioxide in the atmosphere,” the study said.