As the impact of human activities on the environment becomes more marked, there is increased concern about the scale and implications of the changes caused by these activities. Climatic changes that occur as a result of anthropogenic activities will be superimposed upon the natural climatic variability. A key to detection and/or prediction of future global changes lies in understanding the causes and characteristics of variability in the past.
Dendrochronology contributes to the study of global change in many ways. Tree-ring research has produced long-term reconstructions of climate which can be used to:
- Evaluate current variability and trends in climate in the context of past years.
- Identify periods of time or locations of anomalous climate change in the past that may provide clues about the potential behavior of climate and areas that may be particularly sensitive to climate change in the future.
- Study the climatic impact of volcanic eruptions, solar cycles, or El Niño events prior to the advent of instrumental records.
Tree-ring chronologies can provide excellent, exactly dated estimates of climate variability for hundreds or even thousands of years during the Holocene, and therefore are vital for the study of global change.
This map shows the locations of many of the tree-ring chronologies that exist today. Note that most are
located in the Northern Hemisphere, specifically in North America and Europe, and that few chronologies have
been developed for much of Asia. The temperate forests of the Southern Hemisphere also contain trees suitable
for dendrochronology, although few chronologies currently exist for these areas. Recent research has indicated
that a few select tree species growing in tropical areas that experience wet and dry seasons may also contain
annual rings and be useful for dendrochronological studies.
Photo Credits:
Wendy Gross and Connie Woodhouse
NOAA Paleoclimatology Program
