Evidence is mounting that changes in the Sun’s magnetic energy has a much bigger influence on Earth’s weather and climate conditions than previously thought.
New research was able to predict the onset of La Nina weather conditions that produced torrential rains across eastern Australia before they happened, something not previously considered possible. The latest research was published in Earth and Space Science and funded by US space agency, NASA.
The accurate prediction of La Nina extends a six-decade pattern linking changes in magnetic activity in the Sun and El Nino-Southern Oscillation-driven weather conditions on Earth.
The accurate prediction is not proof of a link but dramatically lessens the chances of it being coincidence. The research, led by NASA scientist Robert Leamon from the University of Maryland, Baltimore, tries to “open a broader scientific discussion of solar coupling to the Earth and its environment.”
The exact mechanism that links the Sun’s activity to changes from El Nino to La Nina conditions is not yet understood but the findings add to the belief by some scientists that solar activity, including sunspots and cosmic rays, has a much greater impact on Earth’s climate than thought.
Researchers try to avoid being dragged into controversial theories that have put forward, but they say the findings open debate about the suitability of climate models and the relationship between incoming cosmic rays and clouds and precipitation over our oceans.
The latest research builds on research published last year in the journal Geophysical Research Letters, which was able to map the irregular solar cycle of sunspot activity on to a uniform solar cycle clock that takes place over a 22-year magnetic polarity cycle.
The NASA-funded research uses the new cycle to track changes in the El Nino and La Nina states.
“Using direct observation and proxies of solar activity going back some six decades, we can, with high statistical significance, demonstrate a correlation between the occurrence of terminators and the largest swings of Earth’s oceanic indices: the transition from El Nino to La Nina states of the central Pacific”, the research paper says.
“This empirical relationship is a potential source of increased predictive skill for the understanding of El Nino climate variations, a high‐stakes societal imperative given that El Nino impacts lives, property and economic activity around the globe.’’
The research was published in March 2021 but conducted before the La Nina phase that has just ended. It predicted a rapid transition into La Nina conditions in 2020 following the sunspot cycle 24 terminator.
“A forecast of the Sun’s global behaviour places the next solar cycle termination in mid-2020; should a major oceanic swing follow, the challenge becomes: when does correlation become causation and how does the process work?’’, the paper said.
Researchers presented clear evidence of a recurring empirical relationship between ENSO and the end of solar cycles.
The paper said ENSO was the largest mode of atmospheric variability driving costly extreme weather events on Earth.
Any improvement in prediction of the ENSO cycle would be of societal benefit, the scientists said.