A recent study conducted by the Scripps Institution of Oceanography at the University of California San Diego found that the sun may emit less radiation by mid-century. This, in theory, should give the planet a chance to warm more slowly but not completely counter the effects of climate change. This “cooldown” of the sun would be the result of a phenomenon called the grand minimum. The grand minimum occurs when the sun’s magnetic field diminishes, sunspots form infrequently, and less UV radiation makes it to the planet’s surface. It is theorized that this results from fluctuations in the sun’s magnetic field, happening completely at random.
“There is a well-known 11-year cycle in which the sun’s ultraviolet radiation peaks and declines as a result of sunspot activity,” read a recent Scripps press release. “During a grand minimum, Lubin estimates that ultraviolet radiation diminishes an additional seven percent beyond the lowest point of that cycle. His team’s study, ‘Ultraviolet Flux Decrease Under a Grand Minimum from IUE Short-wavelength Observation of Solar Analogs,’ appears in the publication Astrophysical Journal Letters and was funded by the state of California.”
“This slowing down will only last 2 to 3 solar cycles,” said Dan Lubin, a research physicist at Scripps. “That’s a span of 3 or 4 decades at most, during which time, the sun may dim about 2/10ths of a percent.”
Although this is not a new phenomenon, with sunspots having been observed by both Galileo and English mathematician Thomas Harriot in 1610, there is, in comparison with the earth’s existence, limited historical data. Lubin adds that the cooling of Europe during the 17th century was comparable to what we may see mid-century. “We really don’t have a large historical record of these occurrences,” said Lubin. “For this reason, our team has been working at solar reduction re-creation. This involves looking at stars similar to the sun in a grand minimum state, then estimating the climatic effects.”