New studies show a correlation between the end of the solar cycle and the switch from El Nino to La Nina conditions in the Pacific Ocean, suggesting that solar variability can cause seasonal climate change on Earth.

For connections outlined in the journal Earth and space science If held up, it could significantly improve the predictability of the largest El Nino and La Nino phenomena, which have many seasonal climatic effects on land. For example, the southern United States tends to be warm and dry during the La Niña phenomenon, while the northern United States tends to be cold and moist.

“Energy from the Sun is a major driver of our entire Earth system and enables us to live on Earth,” said Scott McIntosh, a scientist and co-author of the paper at the National Center for Atmospheric Research (NCAR). Says. “Still, the scientific community is not clear about the role that solar variation plays in affecting weather and climate events here on Earth. This study shows why it believes it is, and the loss of connectivity in the past. It shows the reason why it may have been damaged. “

The study was led by Robert Reamon of the University of Maryland in Baltimore County and co-authored by Daniel Marsh of NCAR. This study was funded by the NCAR-sponsored National Science Foundation and the NASA Living With a Star program.

Apply a new sun clock

The appearance (and disappearance) of sun spots (outward-looking signs of solar variation) have been observed by humans for hundreds of years. The number of sunspots increases and decreases in cycles of about 11 years, but these cycles have no clear beginning or end. This ambiguity at a particular cycle length made it difficult for scientists to match the 11-year cycle with the changes taking place on Earth.

In the new study, researchers rely on a more accurate 22-year “clock” of solar activity that derives from the solar cycle of magnetic polarity. This has been outlined in several recently published companion studies as a more regular alternative to the 11-year solar cycle. In a peer-reviewed journal.

According to their recent research, the 22-year cycle begins when the oppositely charged magnetic band that surrounds the Sun appears near the star’s polar latitudes. Throughout the cycle, these bands move toward the equator and show sunspots as they move through mid-latitudes. The cycle ends when the bands meet in the middle and becomes extinct with each other in what the research team calls a terminator event. These terminators provide accurate guideposts for the end of one cycle and the beginning of the next.

Researchers have imposed these terminator events on sea surface temperatures in the tropical Pacific dating back to 1960. They found that all five terminator events that occurred between that time and 2010-11 coincided with a reversal from Ernino (until the sea surface temperature was lanina (if the sea surface temperature was below average) (if the sea surface temperature was below average). (Warmer than average). The end of the latest solar cycle currently unfolding coincides with the beginning of the Laninha phenomenon.

“We are not the first scientists to study how solar variation can change the Earth’s system,” Lemon said. “But we first applied the 22-year solar clock. As a result, the five consecutive terminators alongside the El Nino oscillating switch would not be a coincidence.”

In fact, the researchers did some statistical analysis to determine if the correlation could be just a fluke. They found that all five terminator events included in the study were less than 1 in 5,000 (according to statistical tests) likely to randomly match changes in seawater temperature. The sixth Terminator event (and its corresponding start of the new 2020 solar cycle) also coincided with the La Niña event, making it even less likely to occur randomly.

This paper does not delve into what physical connections between the Sun and the Earth may be responsible for the correlation, but the author includes the effect of the Sun’s magnetic field on the amount of cosmic rays. , States that there may be some possibilities that require further research. Escape into the solar system and eventually bomb the Earth. However, the strong physical link between cosmic ray variability and climate has not yet been determined.

“Further research could improve our ability to predict the El Nino and La Nina phenomena if we can confirm that there is a physical connection and that changes in the Sun are really causing ocean variation.” Mackintosh said.

This article appeared on the Phys.org website at https://phys.org/news/2021-04-ties-solar-variability-onset-decadal.html

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