In order to grow properly, trees need an adequate period of warmth during their growing seasons; otherwise, the cell walls [… ...

Blue growth rings in woody plant stems indicate years when cells failed to lignify properly due to summers that were too cold ...

The scientists collected core samples from 25 Scots pine trees and stem discs from 54 juniper shrubs, creating paper-thin ...

Strange blue rings found in Scandinavian trees leave scientists perplexed - Rings hint at unusually cold summers in Norway between 1877 and 1902 ...

“1902’s cold June could be related to the eruption of Mount Pelée in May. Similarly, the late June eruption of Cotopaxi aligns with 1877’s cold August, but there is no other reported ...

Learn more about these signs of summertime cold, perhaps tied to volcanic activity in 1877 and 1902.

In Norway, scientists have found blue rings in trees that hint at how volcanic eruptions disrupted growth throughout history.

Scientists studying pine trees and juniper shrubs in northern Scandinavia are revealing the weather of the past by looking at tree rings — which can tell us far more than just the trees’ age. ‘Blue’ ...

Scientists studying tree rings in northern Norway have linked ‘blue’ rings, caused by cold summers, to volcanic eruptions ...