Tree Of Knowledge

Research on tree rings is now providing definitive evidence of global warming and its impact on weather systems

- Akshit Sangomla

TREES ARE nature’s secret keepers. Over their long lifetime—some trees can live hundreds, even thousands, of years—they experience a variety of weather conditions, right from floods, droughts, storms and extreme rainfall to forest fires, snowfall, frost, and volcanic eruptions. The information gets stored in the tree trunk as rings—two for each year. Deconstruct these rings and they will narrate how old the tree is and what the weather conditions were like during each year of its life. They are now sought-after repositories of information among climate scientists who are trying to see the big picture.

Meteorologists have been keeping a tab on climate data since the 1850s, but climate scientists want to know about long-term changes in weather conditions and alterations in the frequency or strength of natural events. That would help them ascertain whether the shifting patterns of such events in the recent decades are random, cyclical or part of a trend triggered by global warming. A group of tree ring scientists, or dendrochronologists, are now aggressively scanning dead and living trees for such information that has remained unknown till now.