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Updated: Jun 20, 2026
09:33
A Technical Perspective in Modern Tree-ring Research - How to Overcome Dendroecological and Wood Anatomical Challenges
Published on: March 5, 2015
A relationship between galactic cosmic radiation and tree rings.
Sigrid Dengel1, Dominik Aeby1, John Grace1
1Institute of Atmospheric and Environmental Science, School of GeoSciences, Crew Building, University of Edinburgh, EH9 3JN, UK.
The New Phytologist
|September 17, 2009
Summary
Sitka spruce tree growth in Britain showed a significant link to galactic cosmic radiation flux. This cosmic radiation may influence cloud formation, affecting sunlight and forest photosynthesis.
Area of Science:
- Dendrochronology
- Atmospheric Science
- Astrophysics
Background:
- Investigating interannual variation in Sitka spruce growth rings (1961-2005) in northern Britain.
- Aiming to disentangle atmospheric variable influences on tree growth throughout the year.
Purpose of the Study:
- To correlate Sitka spruce annual growth anomalies with atmospheric variables.
- To explore potential links between tree growth and galactic cosmic radiation.
Main Methods:
- Analysis of annual growth rings from Sitka spruce tree discs.
- Correlation analysis using Pearson product-moment coefficients with climatological data.
- Comparison of tree growth periodicity with galactic cosmic radiation cycles.
Main Results:
- Weak correlations found between tree growth and typical atmospheric factors.
- A consistent and statistically significant relationship identified between tree growth and galactic cosmic radiation flux density.
- Observed periodicity in tree growth mirroring galactic cosmic radiation cycles.
Conclusions:
- Galactic cosmic radiation is a significant factor influencing Sitka spruce growth in northern Britain.
- Hypothesized mechanism involves cosmic radiation affecting cloud condensation nuclei, diffuse solar radiation, and subsequent forest canopy photosynthesis.
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