Tree Rings Reveal Four Grand Solar Minima and Four Potential Miyake Events, Study Finds Scientists use carbon-14 in tree rings to reconstruct past solar storms, identifying four grand solar minima and four potential Miyake events to improve prediction. Scientists have identified four grand solar minima and four potential Miyake events by analyzing carbon-14 in annual tree rings, according to a new study published in Communications Earth & Environment. The research reconstructs past solar activity to help predict when the sun might unleash dangerous bursts of energy and charged particles toward Earth. Solar storms occur when the sun releases a torrent of energy and charged particles far above its normal output. Occasionally, these outbursts are directed at Earth. While they are not dangerous to life on the surface, they can disrupt technology, including satellites, which are particularly vulnerable, and cause problems for airplane travel.The sun's magnetic activity affects how many cosmic rays reach Earth's atmosphere. Those cosmic rays help create radioactive carbon-14, which trees absorb and preserve in their annual growth rings. By measuring changes in carbon-14 levels, scientists can reconstruct past changes in solar activity.The researchers took measurements from annual tree rings to determine when solar storms happened in the past. They also compiled data from previous studies to broaden the scope of their data collection. This approach allowed them to piece together a record of the sun's activity connected to solar storms.Typically, the sun has an 11-year cycle of magnetic activity called a Schwabe cycle, during which it gets stronger and weaker. However, this cycle is not on a strict and predictable schedule, making it difficult to reliably predict the next solar storm.The researchers looked for prolonged periods of low solar activity called grand solar minima by using the carbon-14 record in tree rings. They found four periods that qualified as grand solar minima. By analyzing these periods in relation to solar storm tree rings, scientists were able to get an idea of how quickly the sun's magnetic field recovered from such prolonged inactive periods.This type of data is valuable because modern technology has not continuously measured the sun's activity for very long. To understand long-term behavior and how often bad solar storms happen, researchers need thousands of years of activity records. Tree rings provide that glimpse into the past, helping scientists determine what activity is normal or abnormal.Tree rings also show patterns for powerful solar storms called Miyake events, named after Fusa Miyake, who discovered them during her research. These events are concerning because they are more powerful than standard solar storms and have the potential to cause major technology disruptions.The researchers found four such potential events based on tree ring analysis. They noted in the publication that more research is needed to determine if the solar storms were truly Miyake events, but enough signs were present to consider these dates significant. The events correlated to a spike in carbon-14 followed by a decline over the following years.Scientists want to use this data to understand how frequently Miyake events have happened across Earth's history and how often the sun goes quiet. Potentially, this could help predict the likelihood of the next big solar storm. However, for now the data are limited, given that only so much can currently be gleaned from tree rings and existing historical archives.In previous research, tree rings have revealed a massive solar storm that, if it hit today, could cause a devastating impact. The new findings add to that record by pinpointing specific periods of low solar activity and potential extreme events, offering a longer-term view of the sun's behavior.Understanding the sun's past is essential for preparing for future storms. Satellites, power grids, and communication systems are all vulnerable to solar outbursts. By identifying when the sun was quiet and when it produced massive storms, scientists can better assess the risks and improve prediction models.The study underscores the importance of combining new tree ring samples with historical data. This method allows researchers to extend the record of solar activity far beyond the era of modern instruments. Each ring acts as a natural archive, storing clues about cosmic ray fluctuations and solar cycles.While the four potential Miyake events require further confirmation, they highlight the sun's capacity for extreme behavior. The four grand solar minima provide context for how the sun recovers from inactive periods. Together, these findings help scientists understand the range of solar activity and the likelihood of future disruptions.Future research will focus on refining the dating of these events and expanding the tree ring record. As more data become available, scientists hope to build a more complete picture of solar storms and their impacts. This could lead to better warnings and protective measures for technology-dependent societies.