Researchers from Nagoya University analyzed tree rings recently and discovered that 7000 years ago highly abnormal activity occurred in the Sun during the mid-Holocene. We are presently in the Holocene btw.
The researchers analyzed the level of carbon isotopes (C14 levels) in tree rings from ancient bristlecone pines and found that around 5480 BC the Sun displayed a unique pattern of activity. They then compared this event with more recent events and theorize that there may have been a change in the Sun’s magnetic activity or perhaps there were successive solar burst emissions.
C14 levels in tree rings reflect the cosmic radiation on the atmosphere at the time. When Sun activity changes it has a direct effect on Planet Earth! As an example when the sun is pretty quiet C14 increases in the atmosphere of earth and that C14 is absorbed by trees so C14 levels in the tree’s rings reflect solar activity.
The change in the sun 7000 years ago was abrupt more than previously except for the cosmic ray events that happened in 775 AD and 994 AD. So what happened to the sun 7 kya?
As near as the researchers can tell there was a change in the magnetic activity of the sun that was rather abrupt and it was accompanied by a series of strong solar bursts. In essence what this means is the Sun became very weak! The team plans to conduct additional studies to get a clearer idea of just what happened and what effect it had on the earth.
It does appear that during this time there was a drop in global temperature as reflected in the chart below but still the temps at that time were WARMER than today!
Actually our understanding of the Sun’s behavior is somewhat limited and I’m happy that these researchers are going to continue their research in an effort to more concretely explain just what happened to the sun 7000 kya.