Drought Sensitive 1000-Year Old Trees (IMAGE) Stockholm University Caption Drought sensitive 1000-year old trees from the mountains of Greece. Indirect recorders of past precipitation and drought variability such as tree-ring width data were used by the re-searchers to reconstruct twelve centuries of Northern Hemisphere hydroclimate variability. Credit Photo: Paul J. Krusic Usage Restrictions Creative Commons License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.