The stories contained in tree rings

The Problem

In order to understand how, and why, the changes in our climate happening today are not natural, and pose a danger, we need to understand the long-term climate context – how climate has changed in the past – and how human action has impacted the natural greenhouse effect.

The Method

Studying how our climate has changed throughout time gives context to the changes we are experiencing now. As meteorological records are only available for the last century, we need to analyse natural archives of climate to gain a longer-term picture.

The Tree Ring Research Group at Swansea University are world-leading experts in the analysis of the climate information stored in tree rings.  The group samples ancient trees from forests on every continent where trees grow.

The Impact

• The group’s research has made many scientific discoveries about past climate for example, they have discovered that tree rings from British oak trees contain a chemical signature of how rainy our summers have been, year on year. The team were able to compile a record of how rainy British summers have been over the last 900 years. This world-first record revealed that deterioration of the UK’s climate in the past coincided with terrible famines, and how closely linked our society’s stability is to our climate’s stability.
• The group are also investigating how tree diseases are impacting British woodlands. In our changing climate, trees and woodlands are experiencing more and more diseases stresses. Surviving trees contain a record of the disease history the tree has experienced, in their tree rings, which helps woodland managers understand how these diseases evolve over time.