According to a study from Lund University in Sweden, natural activity from the Sun can also trigger climate change apart from human activities. The research team, for the first time, reconstructed the solar activity at the end of the last ice, around 20,000–10,000 years ago, by analysing trace elements in ice cores in Greenland and cave formations from China.
The study revealed that regional climate is influenced by the Sun. It also helps in predicting future climate conditions in certain regions.
During the last glacial maximum, Sweden was covered in a thick ice sheet that stretched all the way down to northern Germany and sea levels were more than 100 metres lower than they are today, because the water was frozen in the extensive ice caps, researchers said.
“The study shows an unexpected link between solar activity and climate change. It shows both that changes in solar activity are nothing new and that solar activity influences the climate, especially on a regional level. Understanding these processes helps us to better forecast the climate in certain regions,” said Raimund Muscheler, Lecturer in Quaternary Geology at Lund University and co-author of the study.
Researchers said that the Sun’s variation influences the climate in a similar way regardless of whether the climate is extreme, as during the Ice Age, or as it is today.
It is still not confirmed as to how the Sun affects the climate. The study suggests that direct solar energy is not the most important factor, but rather indirect effects on atmospheric circulation.
“Reduced solar activity could lead to colder winters in Northern Europe. This is because the Sun’s UV radiation affects the atmospheric circulation. Interestingly, the same processes lead to warmer winters in Greenland, with greater snowfall and more storms. The study also shows that the various solar processes need to be included in climate models in order to better predict future global and regional climate change,” said Muscheler.